ARTICLE | doi:10.20944/preprints202112.0362.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: rheumatoid arthritis; inflammation, oxidative stress; red blood cells; estrogen receptors.
Online: 22 December 2021 (12:25:17 CET)
Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with a significantly increased risk of cardiovascular mortality, mainly attributed to accelerated atherosclerosis. Methods: Thirty-two women (aged more than 18 years) with RA, and 25 age-matched healthy women were included in this study. Biomarkers of inflammation, red blood cells (RBCs) redox balance, estrogen receptor alpha (ER-α) expression as well as ERK 1/2 phosphorylation content were evaluated in RA patients at baseline and six months after treatment with disease modifying anti‐rheumatic drugs (DMARDs). Results: For the first times we demonstrated that in RA patients: i) disease activity score (DAS-28) positively correlated with RBC ER-α expression, and negatively with total antioxidant capacity of plasma; ii) RBC ER-α expression positively correlated with systemic inflammatory biomarkers and oxidative stress parameters as well as ERK 1/2 phosphorylation; and iii) DMARDs treatments improved the clinical condition measured by DAS-28 score decrease, although the RBCs appeared to be more prone to pro-oxidant status associated to the expression of survival molecules. Conclusion: Our data strongly suggest that RBCs could also participate in vascular homeostasis through fine modulation of an intracellular signal linked to the ER-α.
ARTICLE | doi:10.20944/preprints202010.0080.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: bioflavonoids; superoxide generation; oxidative phosphorylation; translocation
Online: 5 October 2020 (12:13:08 CEST)
In present work, the effects of bioflavonoids (ginkgetin and sciadopitysin) on stimulus-induced superoxide generation, tyrosyl and serine/threonine phosphorylation of proteins in human neutrophils, and the translocation of cytosolic compounds (p47phox, p67phox and Rac) to cell membrane were studied, which were isolated from the needles of Taxus media var. Hicksii. Meanwhile, three normal flavonoids (apigenin, quercetin and isoquercetin) were involved as contrasts. The results indicated that ginkgetin and sciadopitysin were capable of concentration-dependently inhibitory effects on the superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP), arachidonic acid (AA) and phorbol-12-myristate 13-acetate (PMA). And they also suppressed fMLP- and AA- induced tyrosyl or PMA-induced serine/threonine phosphorylation and the translocation of cytosolic compounds (p47phox, p67phox and Rac) to cell membrane, which were in parallel with the suppression of the stimulus-induced superoxide generation. The effect of these compounds on the radical-scavenging was also investigated. Ginkgetin and sciadopitysin did not show remarkable effect on DPPH radical-scavenging activity, and they didn’t display the radical-scavenging activity on superoxide anion generated by phenagine methoxysulfate (PMS)-NADH system. Apparently, ginkgetin and sciadopitysin had great performance in pharmacological value and they are worthy of in-depth study.
ARTICLE | doi:10.20944/preprints201908.0297.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: oxidative status; antioxidant status; oxidative stress; cardiovascular diseases; overweight; obesity
Online: 28 August 2019 (14:51:29 CEST)
Obesity is one of the factors leading to the development of atherosclerosis. This metabolic disorder is associated with an increased production of reactive oxygen species, which affect the oxidative stress level. The aim of this study was to evaluate oxidative/antioxidative status and to investigate the correlation between redox markers and anthropometric parameters and body composition in adult patients after myocardial infarction and in individuals without a cardiovascular event in the past. Descriptive data on socio-demographic, clinical, and anthropometric features and blood samples were collected and categorized into two equal groups: after myocardial infarction (study group (SG), n = 80) and without a cardiovascular event (control group (CG), n = 80). The oxidative/antioxidative status was assessed in plasma on the basis of total oxidative/capacitive status (PerOx), total antioxidative status/capacity (ImAnOx), and oxidized low-density lipoprotein (oxLDL). OxLDL was significantly higher in the CG group compared to the SG group (p = 0.02). No significant differences were found with regard to PerOx and ImAnOx values between the studied groups. Significant positive correlation between PerOx and percentage of adipose tissue (FM [%]) and body adiposity index (BAI) was found in the two studied groups. ImAnOx significantly positively correlated with VAI in SG and FM% in CG. OxLDL negatively correlated with body mass index and waist to hip circumference ratio in CG. The total oxidative/antioxidative status is related to the amount of adipose tissue and the BAI of the subjects. It was observed that it correlates more frequently with the visceral distribution of body fat.
ARTICLE | doi:10.20944/preprints201811.0160.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Aronia melanocarpa berries; cadmium; liver; oxidative/antioxidative balance; oxidative stress; protection
Online: 7 November 2018 (10:47:33 CET)
The study investigated, in a rat model of low-level and moderate environmental exposure to cadmium (Cd; 1 or 5 mg Cd/kg diet, respectively, for 3-24 months), whether the co-administration of 0.1% extract from Aronia melanocarpa L. berries (AE) may protect against oxidative stress in the liver. The intoxication with Cd, dose- and duration-dependently, weakened the enzymatic antioxidative barrier (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase), decreased the concentrations of non-enzymatic antioxidants (reduced glutathione and total thiol groups), and increased the concentrations of oxidized glutathione, hydrogen peroxide, xanthine oxidase, and myeloperoxidase in this organ. These resulted in a decrease in the total antioxidative status (TAS), an increase in the total oxidative status (TOS), and development of oxidative stress in the liver (evaluated based on the index of oxidative stress calculated as the ratio of TOS and TAS). The administration of AE at both levels of Cd treatment significantly improved the enzymatic and non-enzymatic antioxidative barrier, decreased the concentration of pro-oxidants, and protected from the development of oxidative stress in the liver. In conclusion, consumption of aronia products may prevent Cd-induced destroying the oxidative/antioxidative balance and development of oxidative stress in the liver protecting against this organ damage.
ARTICLE | doi:10.20944/preprints201902.0147.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: MWCNTs; oxidative stress; mitochondria
Online: 18 February 2019 (08:57:01 CET)
Human exposure to carbon nanotubes (CNTs) can cause health issues due to their chemical–physical features and biological interactions. These nanostructures cause oxidative stress, also due to endogenous ROS production, which increases following mitochondrial impairment. The aim of this in vitro study was to assess the health effects, due to mitochondrial dysfunction, caused by a sub-chronic exposure to a non-acutely toxic dose of multi walled CNTs (raw and functionalised). The A549 cells were exposed to MWCNTs (2 µg mL-1) for 36 days. Periodically, cellular dehydrogenases, pyruvate dehydrogenase kinase 1 (PDK1), cytochrome c release, permeability transition pore (mPTP) opening, transmembrane potential (Δψ m), apoptotic cells, and intracellular ROS were measured. The results, compared to untreated cells and to positive control formed by cells treated with MWCNTs (20 µg mL-1), highlighted the efficiency of homeostasis to counteract ROS overproduction, but a restitutio ad integrum of mitochondrial functionality was not observed. Despite the tendency to restore, the mitochondrial impairment persisted. Overall, the results underlined the tissue damage that can arise following sub-chronic exposure to MWCNTs.
ARTICLE | doi:10.20944/preprints202009.0642.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: copper; mercury; cadmium; oxidative stress; protein carbonylation; translation factors; oxidative stress biomarkers
Online: 26 September 2020 (14:46:39 CEST)
The impact of metals bioaccumulation on marine organisms is under investigation. This study was designed to determine the association of oxidative stress in mussels Mytilus galloprovincialis induced by seawater enriched with trace metals with protein synthesis. Mussels were exposed to 40 μg/L Cu, 30 μg/L Hg, or 100 μg/L Cd for 5 and 15 days, and the pollution effect was evaluated by measuring established oxidative biomarkers. The results showed damage on the protein synthesis machine integrity and specifically, on translation factors and ribosomal proteins expression and modifications. Exposure of mussels to all metals caused oxidative damage that was milder in the cases of Cu and Hg, and more pronounced for Cd. However, after prolonged exposure of mussels to Cd (15 days), the effects receded. These changes that perturb protein biosynthesis can serve as a great tool for elucidating the mechanisms of toxicity and could be integrated in biomonitoring programs.
COMMUNICATION | doi:10.20944/preprints202005.0446.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: sleep; allometric scaling; oxidative stress
Online: 27 May 2020 (08:29:53 CEST)
Why animals sleep is an outstanding open question. Information about the toxic byproducts of aerobic cellular respiration along with the analysis of patterns in animal size, sleep needs, dietary-type, metabolism, number of heart beats, transportation-network design, and transportation energetics/dynamics suggest that the function of sleep is to maximize the time an animal has to perform its life functions given the finite and constant number of lifetime heart beats it has. Sleep slows down metabolism, and the heart rate, thereby decreasing the load of toxic reactive oxygen species in the cell and extending the cell’s lifetime/proper-functioning. I argue that this is used to maximize the time an animal spends in its ‘effective environment’, which is defined as the period in the light cycle (day or night) where the essential life-functions of that animal (like finding resources, finding sex, hunting) are better achieved. Larger, slow-metabolizing animals need less sleep because their large-bodily-networks and slow metabolisms keep their heart rates relatively low, resulting in a lower rate of oxidative damage, and more relative time in the ‘effective environment’ to get their essential life-functions accomplished.
REVIEW | doi:10.20944/preprints201611.0087.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: bacillithiol; Bacillus; oxidative stress; tRNA
Online: 17 November 2016 (10:40:58 CET)
Oxidative stress occurs when cells are exposed to elevated levels of reactive oxygen species that could damage biological molecules. One bacterial response to oxidative stress involves disulfide bond formation either between protein thiols or between protein thiols and low-molecular-weight thiols. Bacillithiol was recently identified as a major low-molecular-weight thiol in Bacillus subtilis and related Firmicutes. Four genes (bshA, bshB1, bshB2 and bshC) are involved in bacillithiol biosynthesis. The bshA and bshB1 genes are part of a seven-gene operon (ypjD), which includes the essential gene cca, encoding CCA-tRNA nucleotidyltransferase. The inclusion of cca in the operon containing bacillithiol biosynthetic genes suggests that the integrity of the 3’ terminus of tRNAs may also be important in oxidative stress. Addition of the 3´ terminal CCA sequence by CCA-tRNA nucleotidyltransferase to give a mature tRNA and functional molecules ready for aminoacylation plays an essential role during translation and expression of the genetic code. Any defects in these processes, for example, the accumulation of shorter and defective tRNAs under oxidative stress, could exert a deleterious effect on cells. This review summarizes the physiological link between tRNACys regulation and oxidative stress in Bacillus.
REVIEW | doi:10.20944/preprints202301.0321.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Anti-inflamotry; antioxidant; oxidative stress; zebrafish
Online: 18 January 2023 (07:06:34 CET)
This work is based on identifying the analysis techniques used to evaluate the antioxidant and anti-inflammatory effects using the zebrafish model. In this context, a literature review was performed with the Web of Science database. We used the terms zebra fish, antioxidant, anti-inflammatory, model, and Danio rerio. Fifty articles were reviewed, of which thirty-three were chosen to perform this review and were classified according to the source of plant extracts, compounds extracted from plants, chemical compounds, and other sources. This paper is an effort to provide a literature review on zebrafish models and elucidate their pros and cons to evaluate anti-inflamatory and antioxidant activity.
ARTICLE | doi:10.20944/preprints202212.0526.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: hyperglycemia; dyslipidemia; oxidative stress; Gymnema Sylvestre
Online: 28 December 2022 (03:31:07 CET)
The effect of Gymnema Sylvestre supplementation on beta cell and hepatic activity was explored in an alloxan-induced hyperglycemic rat model. Adult rats were made hyperglycemic via a single inj. (i.p) of Alloxan (120mg/kg b.w). Gymnema Sylvestre was supplemented @250mg/kg and 500mg/kg b.w. Blood glucose levels were constantly monitored. After 21 days, rats were euthanized, and blood and tissues (pancreas and liver) were collected for biochemical, expression, and histological analysis. One-way ANOVA was used to compare the means of different treatment groups. Gymnema Sylvestre significantly reduced blood glucose levels with a subsequent increase in plasma insulin levels in a dosage-dependent manner. Total oxidant status (TOS), malondialdehyde, LDL, VLDL, ALT, AST, triglyceride, total cholesterol, total protein, C-reactive protein, and cortisol levels were reduced significantly in alloxan-treated hyperglycemic rats supplemented with Gymnema Sylvestre as compared to control. Significantly raised paraoxonase, arylesterase, albumin, and HDL levels were also observed in Gymnema Sylvestre supplemented hyperglycemic rats. Increased mRNA expression of Ins-1, Ins-2, Gck, Pdx1, Mafa, and Pax6 were observed, while decreased expression of Cat, Sod1, Nrf2, and NF-kB was observed in the pancreas. Whereas increased mRNA expression of Gck, Irs1, SREBP1c, and Foxk1 and decreased expression of Irs2, ChREBP, Foxo1, and FoxA2 were observed in the liver. The current study indicates the potent effect of Gymnema Sylvestre on the transcription modulation of the insulin gene in the alloxan-induced hyperglycemic rat model. Enhanced plasma insulin levels further help to improve hyperglycemia-induced dyslipidemia through transcriptional modulation of hepatocytes.
REVIEW | doi:10.20944/preprints202106.0464.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: Antioxidants; Free radicals; Fructose; Oxidative stress
Online: 17 June 2021 (14:40:02 CEST)
An imbalance in any metabolic system can be traced to its homeostasis. When homeostatic environment is not attainable then there will be a response from the body. A new shift has emerged, “the negative feedback effect of high fructose consumption;” more pain than gain. The human metabolic system daily combat fructose sugar metabolism which emanates from high consumption. This inadvently lead to a chronological series of complications arising from the feedback. These feedbacks play pivotal roles in skeletal muscle damage and other body frameworks, it also fosters toxic advanced glycation end products (AGEs), factors that impose and inflict damaging effects to the body`s energy currency and serious threat to health. These damages are missed or overlooked because of early nonspecific physiological symptoms. High level of fructose has both long- and short-term effects on human metabolic processes. These effects which are majorly through the production of reactive oxygen species (ROS) and other free radicals, are felt in the disruption of biomolecules such as causing DNA mutation, lipid peroxidation etc. these effects in turn lead to various diseases such as cancer, diabetes, atherosclerosis, and other health issues. In this review, we will focus on the damaging effects this sugar has on human health and the present solutions being applied. We will also look at the next step in combatting and controlling these negative feedbacks.
ARTICLE | doi:10.20944/preprints202006.0222.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: astaxanthin; muscle atrophy; mitochondria; oxidative stress
Online: 17 June 2020 (13:29:15 CEST)
Astaxanthin (AX) is a carotenoid that exerts potent antioxidant activity and acts in the lipid bilayer. This study aimed to investigate the effects of AX on muscle atrophy-mediated disturbance of mitochondria that have a lipid bilayer. Tail suspension was used to establish muscle- atrophied mouse models. AX diet fed to tail-suspension mice prevented loss of muscle weight and decreased myofiber size in the soleus muscle. Additionally, AX improved down-regulation of mitochondrial respiratory chain complexes II and III in the soleus muscle after tail suspension. To confirm the AX phenotype in the soleus muscle, we examined its effects on mitochondria using Sol8 myotubes derived from the soleus muscle. We found that AX was preferentially detected in the mitochondrial fraction; it significantly suppressed mitochondrial complex III-driven production of reactive oxygen species in Sol8 myotubes. Moreover, AX inhibited the activation of caspase 3 via inhibiting the release of cytochrome c into the cytosol in antimycin A-treated Sol8 myotubes. These results suggested that AX inhibited mitochondrial oxidative stress through a mitochondria-mediated apoptosis pathway and thus prevented muscle atrophy.
ARTICLE | doi:10.20944/preprints201909.0059.v2
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Oxidative stress, MFN2, mitochondria, fusion/fission
Online: 9 September 2019 (11:46:36 CEST)
Charcot-Marie-Tooth disease is a hereditary polyneuropathy caused by mutations in Mitofusin-2 (MFN2), a GTPase in the outer mitochondrial membrane involved in the regulation of mitochondrial fusion and bioenergetics. Autosomal-dominant inheritance of a R94Q mutation in MFN2 causes the axonal subtype 2A2A which is characterized by early onset and progressive atrophy of distal muscles caused by motoneuronal degeneration. Here, we studied mitochondrial shape, respiration, cytosolic and mitochondrial ATP content as well as mitochondrial quality control in MFN2-deficient fibroblasts stably expressing wildtype or R94Q MFN2. Under normal culture conditions, R94Q cells had slightly more fragmented mitochondria but a similar mitochondrial oxygen consumption, membrane potential and ATP production as wildtype cells. However, when inducing mild oxidative stress 24 h before analysis using 100 µM hydrogen peroxide, R94Q cells exhibited significantly increased respiration but decreased mitochondrial ATP production. This was accompanied by increased glucose uptake and an upregulation of hexokinase 1 and pyruvate kinase M2 suggesting increased pyruvate shuttling into mitochondria. As these changes coincided with decreased levels of PINK1/Parkin-mediated mitophagy in R94Q cells, we conclude that the disease-causing R94Q mutation in MFN2 causes uncoupling of mitochondrial respiration from ATP production by a less efficient mitochondrial quality control triggered by oxidative stress.
REVIEW | doi:10.20944/preprints201811.0189.v4
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: beta-alanine; carnosine; oxidative stress; antioxidant
Online: 28 December 2018 (04:39:00 CET)
The objective of this study was to perform a systematic review and meta-analysis of the articles that addressed the effect BA or carnosine supplementation on physical exercise (PE)-induced oxidative stress (OS). Before May 2018 we searched throughout PubMed, CAPES Periodic and SPORTDiscus human model peer review, randomized control studies with chronic BA or carnosine supplementation on PE-induced OS. A total of 128 citations were found. Only four articles met criteria for inclusion. All four studies used healthy young sedentary, recreationally active or athletic participants. After a chronic BA or carnosine supplementation, the studies evaluated PE-induced OS both immediately and several hours after exercise (0.5 to 48 h). In response to PE-induced OS, when compared to placebo, BA/carnosine supplementation increased total antioxidant capacity [TAC; Effect Size (ES) = 0.35, 95% Confidence Interval (CI) 0.06 to 0.65, p = 0.02] and glutathione (GSH; ES = 0.75, 95% CI 0.32 to 1.19, p = 0.0007) concentrations while decreased direct OS markers (ES = −1.19, 95% CI −1.48 to −0.80, p < 0.01) and superoxide dismutase (SOD) activity (ES = − 0.58, 95% CI −1.10 to −0.06, p = 0.03). BA or carnosine supplementation did not prevent the increase in indirect OS markers (ES: 0.06, 95% CI −0.38 to 0.500, p = 0.80). In humans, following PE-induced OS, initial treatment trials of BA or carnosine supplementation seemed to increase TAC and GSH concentrations, while decreasing SOD activity. Also, albeit mitigating the acute increase in direct OS markers (reactive nitrogen and oxygen species), treatment did not decrease measured values of indirect OS markers (peroxidation or molecule oxidation).
ARTICLE | doi:10.20944/preprints202108.0122.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: Vaping, disposable e-cigarettes, vape bars, flavoring, flavoring chemicals, Reactive Oxidative Species (ROS), disposables, oxidative stress
Online: 4 August 2021 (21:48:02 CEST)
Studies have shown that aerosols generated from flavored e-cigarettes contain Reactive Oxygen Species (ROS), promoting oxidative stress-induced damage within pulmonary cells. Our lab investigated the ROS content of e-cigarette vapor generated from disposable vape bars, a product exempt from the Federal Drug Enforcement Agency’s (FDA) 2020 flavor ban. Specifically, we analyzed vape bars belonging to multiple flavor categories (Tobacco, Minty Fruit, Fruity, Minty/Menthol, Desserts, and Drinks), manufactured by various vendors and of various nicotine concentrations (0-6.8%). Aerosols from these flavored vape bars were generated by a single puff aerosol generator and individually bubbled through a fluorogenic solution to detect and semi-quantify ROS in H2O2 equivalents generated by the vape bars. We compared and contrasted the ROS levels generated by each flavor as an indirect determinant of oxidative stress potential by these disposable vape bars. Our results showed that ROS concentration (μM) of aerosols produced from the vape bars varied significantly between different flavors and a function of nicotine concentration. Likewise, our results suggest that flavoring chemicals and nicotine concentration play a role in alerting ROS production in e-cigarette aerosols. Our study provides insight into the differential health effects of flavored disposable vape bars and the need for their regulation.
REVIEW | doi:10.20944/preprints202302.0454.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Astrocytes, Microglia, Mitochondria, Neurons, Oligodendrocytes, Oxidative stress
Online: 27 February 2023 (07:34:12 CET)
Neurodegeneration is an age-dependent progressive phenomenon with no defined cause. Aging is the main risk factor for neurodegenerative diseases. During aging, activated microglia undergoes phenotypic alterations that can lead to neuroinflammation, which is well accepted event in the pathogenesis of neurodegenerative diseases. Several common mechanisms are shared by genetically or pathologically distinct neurodegenerative diseases, such as excitotoxicity, mitochondrial deficits and oxidative stress, protein misfolding and translational dysfunction, autophagy and microglia activation. Progressive loss of neuronal population due to increased oxidative stress leads to neurodegenerative diseases mostly due to the accumulation of dysfunctional mitochondria. Mitochondrial dysfunction and excessive neuroinflammatory responses are both sufficient to induce pathology in age-dependent neurodegeneration. Therefore, mitochondrial quality control is key determinant for the health and survival of neuronal cells in the brain. Research has been primarily focused to demonstrate the significance of neuronal mitochondrial health, despite the important contributions of non-neuronal cells that constitutes significant portion of the brain volume. Moreover, mitochondrial morphology and function are distinctly diverse in different tissues; however, little is known about their molecular diversity among cell types. Mitochondrial dynamics and quality in different cell types markedly decides the fate of overall brain health, therefore it is not justifiable to overlook non-neuronal cells and their significant and active contribution in facilitating overall neuronal health. In this review article, we aim to discuss the mitochondrial quality control of different cell types in the brain and how important and remarkable is the diversity and highly synchronized connecting property of non-neuronal cells in keeping the neurons healthy to control neurodegeneration.
ARTICLE | doi:10.20944/preprints202302.0084.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Domestic chicken; Broiler chicken; Testosterone; Oxidative stress
Online: 6 February 2023 (07:38:07 CET)
Consumption of poultry meat is higher than red meat due to easy availability, good taste, low cost and palatability. Significant improvement in meat yield and growth rate of broiler chicken has been brought about with the help of genetic selection of desirable traits. The present study was conducted to comparatively evaluate the chronic effect of domestic and broiler chicken meat consumption on male hypothalamic pituitary gonadal axis, lipid profile and oxidative stress on postnatal male rats. Rats were divided into five groups: control, B1, B2, D1 and D2 groups and were fed with 0.17g and 0.34g of broiler and domestic chicken meat from postnatal day 21 to PND90.The significant elevated body weight and weight gain in B2 group (P<0.01), minor change in B1 and D40 group (P<0.05) were detected. In gonadosomatic index absolute and relative epididymis weight, weight of seminal vesical and Prostate weight was significantly augmented in B2 compared to control and D2. Kidney and liver weight in B1, B2 was markedly elevated and minor change in D2 groups. ROS level in B2 was significantly higher than other experimental groups. Serum level of FSH, LH, testosterone, estradiol and low density lipoprotein was significantly elevated in B2 compared to control and D2. In B2 rats fed with 0.34g broiler meat exhibited a marked decreased seminiferous tubule diameter, epithelial height and increased lumen diameter changes that were more prominent compared to rats fed with 0.34g domestic chicken meat. Conclusively chronic administration of broiler meat induces marked alteration in reproductive system, testicular morphology, sexual hormones and oxidative stress in postnatal Sprague Dawley male rats compared to domestic chicken meat.
ARTICLE | doi:10.20944/preprints202301.0373.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: alternative drugs; cryptococcosis; oxidative stress; synthetic peptides
Online: 20 January 2023 (15:17:15 CET)
Cryptococcus neoformans is a human multidrug-resistant yeast with high mortality rates in immunocompromised patients. Recently, the synthetic peptide Mo-CBP3-PepII emerged as a potent anticryptococcal molecule with an MIC50 at low concentration. Here, the mechanisms of action of Mo-CBP3-PepII were deeply analyzed to provide new information about how it led C. neoformans cells to death. Light and fluorescence microscopies, analysis of enzymatic activities, and proteomic analysis were employed to understand the effect of Mo-CBP3-PepII on C. neoformans cells. Light and fluorescence microscopies revealed Mo-CBP3-PepII induced the accumulation of anion superoxide and hydrogen peroxide in C. neoformans cells. In addition to a reduction in the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) in the cells treated with Mo-CBP3-PepII. In the presence of Ascorbic acid (AsA), no ROS were detected and Mo-CBP3-PepII lost the inhibitory activity against C. neoformans. Yet, Mo-CBP3-PepII inhibited the activity of lactate dehydrogenase (LDH), ergosterol biosynthesis, and induced the decoupling of cytochrome c from the mitochondrial membrane. Proteomic analysis revealed a reduction in the abundance of proteins related to energetic metabolism, DNA and RNA metabolism, pathogenicity, protein metabolism, cytoskeleton, and cell wall organization and division. Our findings indicated that Mo-CBP3-PepII might have multiple mechanisms of action against C. neoformans cells, mitigating the development of resistance and thus being a potent molecule to be employed in the production of new drugs against C. neoformans infections.
ARTICLE | doi:10.20944/preprints202301.0274.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: chrysoeriol; embryo development; porcine; oxidative stress; autophagy
Online: 16 January 2023 (07:54:26 CET)
Chrysoeriol (CHE) is a flavonoid substance that exists in many plants and has various physiological and pharmacological effects, including anti-inflammatory, antioxidant, anti-tumor, and protective activity, especially for the cardiovascular system and liver. This study aimed to analyze the results and possible mechanisms of CHE on early porcine embryo development. Adding CHE to the culture media can improve the development quality of early porcine embryos. CHE significantly increased the blastocyst rate and total cell number of embryos in vitro. The apoptosis of blastocyst in CHE-treated culture also decreased significantly compared with untreated culture. Furthermore, CHE downregulated intracellular reactive oxygen species (ROS) and increased glutathione (GSH) in embryos. CHE was also shown to improve the activity of mitochondria and inhibit the occurrence of autophagy. In addition, antioxidant-related genes (SOD1, SOD2, and CAT) and cell pluripotency-related genes (SOX2, OCT4, and NANOG) were upregulated, while those related to apoptosis (Caspase 3) and autophagy (LC3B) showed a downward trend after supplementation with CHE. These results indicated that CHE improved the development of porcine embryos in vitro by reducing oxidative stress and autophagy levels.
ARTICLE | doi:10.20944/preprints202210.0300.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Nrf2; Oxidative stress; Antioxidants; Pentylenetetrazol; Epilepsy; Seizure
Online: 20 October 2022 (08:29:58 CEST)
The modulation of Nrf2 activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post-status epilepticus rat model, however, the spatio-temporal, as well as cell type-specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the cortex and the hippocampus up to 1-week following the induced seizure. We found that after a pentylenetetrazol-induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 to 6 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3-6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co-localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.
ARTICLE | doi:10.20944/preprints202210.0195.v2
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Warburg effect, oxidative stress, magnesuria, inflammasome, butyrate
Online: 14 October 2022 (12:56:34 CEST)
Long Covid has many symptoms that overlap with ME(myalgic encephalomyelitis)/CFS(chronic fatigue syndrome), FM(fibromyalgia), EBV(Epstein-Barr virus), CMV(cytomegalovirus), CIRS (chronic inflammatory response syndrome), MCAS(mast cell activation syndrome), POTS(postural orthostatic tachycardia syndrome), and post viral fatigue syndrome. They all portend a “long haul” with an antioxidant shortfall and elevated Ca:Mg. Oxidative stress is the root cause. Linkage between TGF(transforming growth factor)-β, IFN(interferon)-γ, the RAS(renin angiotensin system), and the KKS(kallikrein kinin system) is discussed. Technical explanations for the renin aldosterone paradox in POTS, the betrayal of TGF-β, and the commonality of markers for the Warburg effect are offered. The etiology of the common Long Covid symptoms of post exertional malaise, fatigue, and brain fog as well as anosmia, hair loss, and GI symptoms is technically discussed. Ca:Mg is critical to the glutamate/GABA balance. The role of GABA and butyrates from the “good” intestinal bacteria in the gut-brain axis and its correlation with chronic fatigue diseases are explored. The crosstalk between the ENS(enteric nervous system) and the ANS(autonomic nervous system) and the role of the vagus in both are emphasized. HRV(heart rate variability), the fifth vital sign, points to an expanded gut-brain-heart/lung axis. A suggested approach to all of these - Long Covid, chronic fatigue diseases, post viral fatigue syndrome, and general health - is presented.
ARTICLE | doi:10.20944/preprints202209.0437.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Semen; hesperidin; cryopreservation; oxidative stress; antioxidant; ram
Online: 28 September 2022 (09:35:03 CEST)
We conducted this study to determine the potential cryopreservative effects of different hesperidin (vitamin P; HSP) doses on ram semen after freeze-thawing. Semen samples were obtained from Sönmez rams by an artificial vagina. The samples were divided into six groups: control, 10, 50, 100, 250, and 500 µg/mL HSP (C, HSP10, HSP50, HSP100, HSP250, and HSP500, respectively). At the end of the study, sperm motility and kinetic parameters, plasma membrane acrosome integrity (PMAI), high mitochondrial membrane potential (HMMP), viability, lipid peroxidation levels (LPL), chromatin damage, oxidant parameters, and antioxidant parameters were assayed. None of the doses of HSP added to the semen extender showed any enhancing effect on progressive motility compared to C (p>0.05). In fact, HSP500 had negative effects (p<0.05). Moreover, PMI activities were the highest at the HSP10 dose, while LPL values were the lowest (p<0.05). The doses of HSP10 and HSP50 added to the Tris extender medium showed positive effects on spermatozoon chromatin damage. Consequently, we can say that HSP doses used in this study are not effective on semen progressive motility, but the HSP10 dose is effective on PMAI and chromatin damage by reducing LPL.
ARTICLE | doi:10.20944/preprints202209.0066.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: Silicon; Heavy metals; Oxidative stress; Wheat; Cellular
Online: 5 September 2022 (13:44:44 CEST)
Silicon is an essential trace nutrient for plant growth and is frequently employed to remediate soils contaminated with heavy metals in agriculture. However, silicon’s role and mechanism in reducing heavy metal toxicity have not been well understood, especially for multi-heavy metals. In this study, the effects of silicon-rich materials (silicate, rice husk biochar (RHB), and bentonite) on growth trait, antioxidant response, and heavy metal accumulation and distribution of wheat grown in two soils polluted by multiple heavy metals (Cd, Zn, Pb, and As) were investigated. The results revealed that the addition of silicon-rich materials enhanced plant growth, improved the photosynthetic attributes in leaf tissues, and decreased the contents of Cd, Zn, Pb, and As in wheat shoots and grains. The examination of the subcellular distribution of heavy metals in plants implied that silicon-rich materials transferred heavy metals as intracellular soluble fractions to the cell walls, indicating the reduction of mobility and toxicity of heavy metals in the plants. In addition, the application of the silicon-rich materials reduced oxidative damage in plants by downregulating plant antioxidant response systems and decreasing the production of malondialdehyde (MDA), ascorbic acid (AsA), and glutathione (GSH). Moreover, fractionation analysis of soil heavy metals showed that silicon-rich amendments could convert bioavailable heavy metals into immobilized forms. The results indicated that silicon-rich materials could remediate multi-heavy metal-polluted soils and promote wheat production.
ARTICLE | doi:10.20944/preprints202208.0485.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: Arsenic; global warming; invertebrates; behavior; oxidative stress
Online: 29 August 2022 (10:43:42 CEST)
Contamination with Arsenic, a toxic metalloid, is increasing in the marine environment. Additionally, global warming can alter metalloids toxicity. Polychaetes are key species in marine environments. By mobilizing sediments, they play vital roles in nutrient and element (including contaminants) cycles. Most studies with marine invertebrates focused on the effects of metalloids on either adults or larvae. Here we bring information on the effects of temperature increase and arsenic contamination on the polychaete Hediste diversicolor in different growth stages and water temperatures. Feeding activity and biochemical responses – neurotransmission, indicators of cell damage, antioxidant and biotransformation enzymes and metabolic capacity - were evaluated. Temperature rise combined with As imposed alterations on feeding activity and biochemical endpoints at different growth stages. Small organisms have their antioxidant enzymes increased, avoiding lipid damage. However, larger organisms are the most affected class due to inhibition of superoxide dismutase, which resulted in protein damage. Oxidative damage was observed on smaller and larger organisms exposed to As and 21 °C, demonstrating higher sensibility to the combination of temperature rise and As. The observed alterations may have ecological consequences, affecting the cycle of nutrients, sediment oxygenation and the food chain that depend on the bioturbation of this polychaete.
ARTICLE | doi:10.20944/preprints202112.0161.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Nrf2; Keap1; oxidation; oxidative stress; protein misfolding
Online: 9 December 2021 (15:46:41 CET)
Cells that experience high levels of oxidative stress respond with the induction of antioxidant proteins through the activation of the transcription factor Nrf2. Nrf2 is negatively regulated by Keap1 which binds to Nrf2 to facilitate its ubiquitination and ensuing proteasomal degradation under basal conditions. Here, we study protein folding and misfolding in Nrf2 and Keap1 in yeast, mammalian cells, and purified proteins under oxidative stress conditions. Both Nrf2 and Keap1 are susceptible to protein misfolding and inclusion formation upon oxidative stress. We propose that the intrinsically disordered regions within Nrf2 and the high cysteine content of Keap1 contribute to their oxidation and the ensuing misfolding. Our work reveals previously unexplored aspects of Nrf2 and Keap1 regulation and dysregulation by oxidation-induced protein misfolding.
COMMUNICATION | doi:10.20944/preprints202108.0302.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: stroke; liposome; cerebrovascular disease; oxidative stress; dementia
Online: 13 August 2021 (15:37:59 CEST)
Neuroprotective strategies for stroke remain inadequate. Nanoliposomes comprised of phos-phatidylcholine, cholesterol and monosialogangliosides (NL) induced an antioxidant protective response in endothelial cells exposed to amyloid insults. We tested the hypotheses that NL will preserve SH-SY5Y neuroblastoma cell viability following hypoxic injury and will reduce injury in mice following middle cerebral artery occlusion (MCAO). Neuroblastoma were exposed to 20-hour physoxic (5% oxygen) or hypoxic (1% oxygen) condition without or with NL (100 or 300 µg/mL). Viability was measured using calcein-AM fluorescence and SH-SY5Y gene expression of antioxidant proteins heme oxygenase-1 (HO-1), NAD(P)H quinone dehydrogenase 1 (NQO1) and superoxide dismutase 1 (SOD1) were measured by quantitative polymerase chain reaction. C57BL/6J mice were treated with saline (N=8) or NL (10000 ug/mL, N=7) while undergoing 60-minute MCAO followed by reperfusion. Day 2 post-injury neurologic impairment score and infarction size were compared. Neuroblastoma showed reduced viability following hypoxia that was reversed by NL. NL increased gene expression of HO-1, NQO1 and SOD1 versus controls. NL-treated mice showed reduced neurologic impairment and brain infarct size (18.8±2% versus 27.3±2.3%, p=0.017) versus controls. NL reduced stroke injury in mice subjected to MCAO likely through induction of an antioxidant stress response. NL is a candidate novel agent for stroke.
ARTICLE | doi:10.20944/preprints202107.0042.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: Spinal Cord Injury; Oxidative stress; Antioxidants, Pain
Online: 2 July 2021 (09:05:08 CEST)
Introduction:In this study we evaluated the connivance of oxidative and antioxidative parameters in the pathogenesis of spinal cord injury (SCI). Although the etiology and pathogenesis of SCI remain to be fully understood, it has been suggested that reactive oxygen species (ROS) and oxidative stress may play a significant role in the pathophysiology of SCI. Furthermore, there is little information available in scientific literature about oxidative and antioxidative parameters in SCI patients. Methods:Oxidative stress was determined by measuring the levels of Lipid Peroxides (LPO) and Protein carbonyl in plasma and antioxidative parameters like Glutathione Reductase (GR), catalase and Glutathione peroxidase (GPx) in lysate in 40 SCI patients and 40 healthy subjects without SCI. However, pain was measured by McGill pain questionnaire. Results: Concentrations of catalase (p<0.01), GR (p<0.01) and GPx (p<0.01) were significantly lower in patients with SCI than in controls, and levels of oxidative stress parameters, LPO (p<0.01), Protein carbonyl (p<0.01) were significantly higher in patients than in controls. A significant positive correlation was found between LPO and pain score among SCI patients group. Furthermore, a significant positive correlation was also found between Protein carbonyl and pain score among SCI patients group than in control group. Conclusion: The present results indicate that SCI patients are exposed to oxidative stress and this escalated oxidative stress may play a role in the etiopathogenesis of the disease. Moreover, our results also show that increased oxidative stress parameters are more strongly amalgamated with pain in SCI patients.
ARTICLE | doi:10.20944/preprints202105.0136.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: CDAHFD; NASH; Mitochondrial dysfunction; Liver; Oxidative stress
Online: 7 May 2021 (09:47:44 CEST)
The prevalence of nonalcoholic fatty liver disease (NAFLD) has been rapidly increasing worldwide. A choline-deficient L-amino acid-defined high fat diet (CDHFD) has been used to create a mouse model of nonalcoholic steatohepatitis (NASH). There are some reports about the effects on mice of being fed CDAHFD for a long time, 1 to 3 months. However, the effect of this diet over a short period has been unknown. Therefore, we examined the effect of one week of feeding CDAHFD on the mouse liver. Feeding this diet for only one week induced lipid droplet deposition in the liver with increasing activity of liver-derived enzymes in the plasma. On the other hand, it did not induce fibrosis and cirrhosis. Additionally, it was demonstrated that mitochondrial respiration is significantly impaired with severe oxidative stress in the liver by CDAHFD, associated with a decreasing mitochondrial DNA copy number and complexes-proteins. In the gene expression analysis of the liver, inflammatory and oxidative stress markers were significantly increased by CDAHFD. These results demonstrated that one week of feeding CDAHFD to mice induces steatohepatitis with mitochondrial dysfunction and severe oxidative stress, without fibrosis, which can partially mimic the early stage of the NASH in humans.
REVIEW | doi:10.20944/preprints202101.0025.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Astaxanthin; natural antioxidant; bacteriocins; hispidin; oxidative stress
Online: 4 January 2021 (12:15:33 CET)
Oxidative stress is an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately negotiating cells viability. Antioxidants can scavenge such free radicals, thus reducing the oxidative stress and eventually prevent cellular damage. Medicinal plants, fruits, and spices remain the prioritized sources of antioxidants and antimicrobial properties since the time immemorial, but in contrast to plants, microorganisms can be grown at a faster rate under controlled conditions. They are non-toxic, non-carcinogenic, and biodegradable as compared to synthetic antioxidants. Microorganisms including actinomycetes, archaea, bacteria, protozoa, yeast, and fungi are auspicious source of vital bioactive compounds. The list comprises ample of bioactive components from microorganisms. One of them is bacteriocins, which are ribosomally synthesized antimicrobial peptides product of Eurotium sp., Streptomyces parvulus, S. thermophiles, Lactococcus lactis, etc. It has a great potential as next-generation antibiotics targeting the multiple-drug resistant pathogens. Pneumocandins are antifungal lipohexapeptides derived from the fungus Glarea lozoyensis, and inhibit 1,3-β-glucan synthase of the fungal cell wall and act as a precursor for the synthesis of caspofungin. It is widely used against invasive fungal infections and has been recently approved by the FDA. Taxol (paclitaxel), a chemotherapeutic drug derived from the bark of Taxus brevifolia can also be produced by endophytic fungi Taxomyces andreanae and Nodulisporium sylviforme. It is known to inhibit several fungi such as Pythium, Aphanomyces and Phytophthora. Hispidin and its derivate isolated from P. hispidus, reduce inducible nitric oxide synthase (iNOS) expression, obstruct the transcriptional activity of NF-κB, and also decrease the production of reactive oxygen species (ROS) in macrophages. Astaxanthin, known as an “aquatic” carotenoid produced by H. pluvialis, also has excellent ROS quenching activity. This study mainly focuses on fascinating antioxidant and antimicrobial compounds that have been scarcely investigated in microorganisms and discuss the promise and challenges of microorganisms as providers of health benefits.
ARTICLE | doi:10.20944/preprints202101.0014.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: delirium; inflammation; neuro-immune; biomarkers; oxidative stress
Online: 4 January 2021 (11:26:34 CET)
Background: Post-operative delirium in elderly with hip fracture is associated with various adverse clinical outcomes. Nevertheless, the pathophysiological processes underpinning delirium have remained elusive. The aim of this study is to explore the associations between delirium and its features and immune-inflammatory and blood gas biomarkers.Methods: In this prospective study we examined 65 patients who underwent a hip fracture surgery and assessed the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU), Richmond Agitation-Sedation Scale (RASS), and Delirium Rating Scale Revised-98 (DRS-R-98) before and during 4 days after the surgery. Complete Blood Count (CBC) and venous blood gas markers were obtained at the same time points.Results: Delirium was observed in 19 patients and was accompanied by significantly increased pO2, number of white blood cells, neutrophil percentage, and neutrophil/lymphocyte ratio, and lower mean platelet volume (MPV) (after adjusting for age, central nervous system (CNS) disease, blood loss during surgery, sleep disorders, and body mass index. The severity of delirium was associated with lowered number of platelets and MPV. Psychomotor disorders were associated with lower bicarbonate levels. The requirement of physical restraint of the patients was predicted by increased percentages of neutrophils and lymphocytes. Prior CNS disease was together with these biomarkers a significant predictor of delirium and severity of delirium. Conclusion: Delirium and psychomotor disorders following hip fracture and surgery may be caused by immune-inflammatory and oxidative stress pathways probably attributable to an aseptic inflammatory process. Oxygen administration may aggravate these pathways.
ARTICLE | doi:10.20944/preprints202012.0550.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Metals; Isoprostane; Biomarkers; Oxidative stress; Puerto Rico.
Online: 22 December 2020 (10:33:04 CET)
Metal exposure has been associated with a wide range of adverse birth outcomes and oxidative stress is a leading hypothesis of the mechanism of action of metal toxicity. We assessed the relationship between maternal exposure to essential and non-essential metals and metalloids in pregnancy and oxidative stress markers, and sought to identify windows of vulnerability and effect modification by fetal sex. In our analysis of 215 women from the PROTECT birth cohort study, we measured 14 essential and non-essential metals in urine samples at three time points during pregnancy. The oxidative stress marker 8-iso-prostaglandin F2α (8-iso-PGF2α) and its metabolite 2,3-dinor-5,6-dihydro-15-15-F2t-IsoP, as well as prostaglandin F2α (PGF2α), were also measured in the same urine samples. Using linear mixed models, we examined the main effects of metals on markers of oxidative stress as well as the visit-specific and fetal sex-specific effects. After adjustment for covariates, we found that a few urinary metal concentrations, most notably cesium (Cs) and copper (Cu), were associated with higher 8-iso-PGF2α with effect estimates ranging from 7.3 to 14.9 % for each interquartile range, increase in the metal concentration. The effect estimates were generally in the same direction at the three visits and a few were significant only among women carrying a male fetus. Our data show that higher urinary metal concentrations were associated with elevated biomarkers of oxidative stress. Our results also indicate a potential vulnerability of women carrying a male fetus.
ARTICLE | doi:10.20944/preprints202006.0166.v2
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Tattoo; Tattoo ink; Oxidative stress; Phthalocyanine; Skin
Online: 2 December 2020 (11:05:29 CET)
Biomedical aspects of tattooing have been extensively discussed in literature, however pathophysiological effects of tattoo inks in the human body are still unexplored. Oxidative stress is considered responsible for the adverse effects of tattooing, however no experimental evidence for tattoo ink-related oxidative stress in the human body currently exists. The aim was to examine the effect of a blue tattoo on skin redox regulatory network (RRN) parameters in a single human subject. Skin surface oxidation-reduction potential (ORP) was analyzed with a PH60F flat probe. Interstitial and intracellular fluid enriched capillary blood from the tattoo and the control area was extracted and analyzed with I2/KI-stabilized microORP, nitrocellulose redox permanganometry (NRP), carbonato-cobaltate (III) formation-derived H2O2 dissociation rate assay, 1,2,3-trihydroxybenzene autoxidation assay, thiobarbituric reactive substances (TBARS) assay and 5,5,’-dithio-bis-(2-nitrobenzoic acid) (DTNB)-based determination of free thiol content in low molecular weight and protein precipitate fractions. Surface ORP analysis revealed a greater antioxidant capacity of tattooed skin in comparison with the control (CTR). Capillary blood analysis confirmed greater reductive capacity in the tattoo sample both by microORP (-4.33mV vs CTR) and NRP (+10.8%). Hydrogen peroxide dissociation rate (+11.8%), and protein sulfhydryl content (+8.5%) were increased, and lipid peroxidation (-15%) was reduced in the tattoo sample in comparison with the CTR. In this N-of-1 study, RRN of tattooed skin was shifted towards a more reductive state with all parameters indicating reduced levels of oxidative stress in comparison with nontattooed skin. The local antioxidant effect of copper(II) phthalocyanine provides one possible explanation of the observed effects.
REVIEW | doi:10.20944/preprints202010.0580.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Immune system; Oxidative stress; Nanoparticles; Intracellular Pathogens
Online: 28 October 2020 (10:05:05 CET)
The immune system is a dynamic network of cells and cytokines are the major mediators of immune responses which combat pathogens. Based on the cytokine production, effector T cells differentiate into subsets known as Th1, Th2, Th17 or Treg (T regulatory). This system serves as a barrier to intracellular pathogens, bacterial infections and stimulates the production of reactive oxygen species (ROS), reactive nitrogen intermediates (RNI) and nitric oxide (NO), which diffuses across membranes and engulfs intracellular pathogens. Oxidative stress occurs when ROS, reactive nitrogen species (RNS) production and antioxidant defences become imbalanced. Oxidative stress generated by infected cells produces a substantial amount of free radicals which enables killing of intracellular pathogens. Intracellular pathogens are exposed to endogenous ROS as part of normal aerobic respiration, also aexogenous ROS and RNS are generated by the host immune system in response to infection. Nanoparticles which are designed for drug delivery are capable of trapping the desired drug in the particles which protects the drug from enzymatic degradation in a biological system. The small (subcellular) size of nanoparticles enables higher intracellular uptake of the drug which results in the reduction of the concentration of free drugs reducing their toxic effect. Research on the modulation of immune response and oxidative stress using nanoparticles used to encapsulate drugs has yet to be explored fully. In this review we illustrate the immune activation and generation of oxidative stress properties which are mediated by nanoparticle encapsulated drug delivery systems which can make the therapy more effective in case of diseases caused by intracellular pathogens.
ARTICLE | doi:10.20944/preprints201912.0219.v3
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Nitric oxide; Oxidative stress; Ethanol withdrawal; Anxiety
Online: 2 April 2020 (11:01:26 CEST)
Nitric oxide has been implicated in symptoms of ethanol withdrawal in animal models. Zebrafish have been used as models to study neurobehavioral effects of ethanol (EtOH) withdrawal, but the mechanisms associated with these effects are not yet clear. Adult zebrafish were treated with 1% EtOH for 20 min per day for 8 days, injected with the nitric oxide synthase 2 (NOS-2) inhibitor aminoguanidine (50 mg/kg), and allowed to experience withdrawal (WD) in their hometanks for 7 days. EtOH WD increased anxiety-like behavior in the novel tank test, an effect that was blocked by aminoguanidine. EtOH WD also increased brain levels of nitrite, an effect that was partially blocked by aminoguanidine. These results underline a novel mechanism by which NOS-2 controls anxiety-like responses to ethanol withdrawal, with implications for the mechanistic study of symptoms associated with chronic ethanol abuse.
ARTICLE | doi:10.20944/preprints202001.0105.v1
Subject: Biology And Life Sciences, Aging Keywords: osteoarthritis; carnosine; hyaluronic acid; inflammation; oxidative stress
Online: 11 January 2020 (11:17:18 CET)
Osteoarthritis (OA) is a disease that currently has no cure. There are numerous studies showing that carnosine and hyaluronic acid (HA) have a positive pharmacological action during joint inflammation. For this reason, the goal of this research was to discover the protective effect of a new HA+Carnosine formulation (FidHycarn) on the inflammatory response and on the cartilage degradation in in vivo experimental model of OA. This model was induced by a single intra-articular (i.ar.) injection of 25µl normal saline having 1mg of monosodium iodoacetate solution (MIA) in the knee joint. MIA injection caused histological alterations and degradation of cartilage as well as behavioral changes. Oral treatment with FidHycarn ameliorated the macroscopic signs, improved thermal hyperalgesia and weight distribution of hind paw as well as decreased histological and radiographic alterations. The oxidative damage was analyzed by evaluating the levels of nitrotyrosine and inducible nitric oxide synthase (iNOS) that were significantly reduced in FidHycarn rats. Moreover, the levels of pro-inflammatory cytokines and chemokines were also significantly reduced by FidHycarn. However, interestingly, in more cases, the effects of FidHycarn were not statistically different to Naproxen used as positive control. Thus, the new formulation containing Carnosine and HA could represent an interesting therapeutic strategy to combat osteoarthritis.
COMMUNICATION | doi:10.20944/preprints201810.0472.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: vitamin D; oxidative stress; kidney disease, disparities
Online: 22 October 2018 (05:42:44 CEST)
Chronic kidney disease (CKD) is a major non-communicable disease associated with high rates of premature morbidity and mortality. The prevalence of hypovitaminosis D (deficiency of 25(OH)D or 25D) is greater in racial/ethnic minorities and in patients with CKD than the general population. Low 25D is associated with bone and mineral disorders as well as immune, cardiometabolic and cardiovascular (CV) diseases. Thus, it has been suggested low 25D contributes to the poor outcomes in patients with CKD. The prevalence of hypovitaminosis D rises progressively with advancing severity of kidney disease with over 30% of patients with CKD stage 3 and 70% patients with CKD stage 5 estimated to have low levels of 25D. This report describes several of the abnormal physiologic and counter-regulatory actions related to low 25D in CKD such as those in oxidative stress and inflammatory systems, and some of the preclinical and clinical evidence or lack of thereof of normalizing serum 25D levels to improve outcomes in patients with CKD, and especially for the high risk subset of racial/ethnic minorities who suffer from higher rates of advanced CKD and hypovitaminosis D.
ARTICLE | doi:10.20944/preprints201808.0303.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: pine bark extract; oxidative stress; muscle damage
Online: 17 August 2018 (12:07:49 CEST)
The purpose of the present study was to examine if 14 days of supplementation with a pine bark extract leading up to and following an exercise test would increase performance and reduce biomarkers associated with muscle damage, inflammation and oxidative stress. The study used a double-blind, placebo controlled, cross-over design. Participants ingested either 800mg pine bark extract or placebo for 14 days prior to the first exercise trial and for 2 days post-exercise. On the exercise day, participants submitted a pre-exercise blood sample, then completed a VO2 peak test until volitional failure. A post-blood sample was collected 1 hour after completion of exercise. Participants returned at 24 & 48 hours after the exercise testing for measures of muscle pain in the lower body using an algometer. Participants then had a 7-day washout period before beginning to crossing over to the alternate treatment. Analysis via ordinal regression demonstrated a significant difference in oxidative stress in the pine bark extract group compared to placebo (ChiSq = 2.63; p = 0.05). The pine bark extract was effective at affording protection from oxidative stress post exercise. Further work should be undertaken to evaluate the findings with other exercise modes or in participants with known metabolic syndrome.
ARTICLE | doi:10.20944/preprints201807.0527.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: autophagy; huntingtin; insulin signaling; liraglutide; oxidative stress
Online: 27 July 2018 (03:35:44 CEST)
Huntington's disease (HD) is a progressive and fatal neurodegenerative disease caused by CAG repeat expansion in the coding region of huntingtin (HTT) protein. The accumulation of mutant HTT (mHTT) contributes to neurotoxicity by causing autophagy defects and oxidative stress that ultimately lead to neuronal death. Interestingly, epidemiologic studies have demonstrated that the prevalence of type-2 diabetes, a metabolic disease mainly caused by defective insulin signaling, is higher in patients with HD than in healthy controls. Although the precise mechanisms of mHTT-mediated toxicity remain unclear, the blockade of brain insulin signaling may initiate or exacerbate mHTT-induced neurodegeneration. In this study, we used an in vitro HD model to investigate whether neuronal insulin signaling is involved in mHTT-mediated neurotoxicity. Our results demonstrated that mHTT overexpression significantly impairs insulin signaling and causes apoptosis in neuronal cells. However, treatment with liraglutide, a GLP-1 analogue, markedly restores insulin sensitivity and enhances cell viability. This neuroprotective effect may be attributed to the contribution of the upregulated expression of genes associated with endogenous antioxidant pathways to oxidative stress reduction. In addition, liraglutide stimulates autophagy through AMPK activation, which attenuates the accumulation of HTT aggregates within neuronal cells. Our findings collectively suggest that liraglutide can rescue impaired insulin signaling caused by mHTT and that GLP-1 may potentially reduce mHTT-induced neurotoxicity in the pathogenesis of HD.
REVIEW | doi:10.20944/preprints201807.0260.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: mitochondria; invertebrate; reactive oxygen species; oxidative phosphorylation
Online: 16 July 2018 (08:27:03 CEST)
Neurodegenerative diseases like Alzheimer’s disease (AD) are poised to become a global health crisis, and therefore understanding the mechanisms underlying the pathogenesis is critical for the development of therapeutic strategies. Mutations in genes encoding presenilin occur in most familial Alzheimer’s disease but the role of PSEN in AD is not fully understood. In this review, the potential modes of pathogenesis of AD are discussed, focusing on calcium homeostasis and mitochondrial function. Moreover, research using Caenorhabditis elegans to explore the effects of calcium dysregulation due to presenilin mutations on mitochondrial function, oxidative stress and neurodegeneration is explored.
ARTICLE | doi:10.20944/preprints201803.0184.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: colorectal cancer cells; metformin; apoptosis; oxidative stress
Online: 21 March 2018 (03:30:49 CET)
Accumulating evidence suggests that metformin, used as an antidiabetic drug, possesses anticancer properties. Metformin reduced the incidence and growth of experimental tumors in vivo. In a randomized clinical trial among nondiabetic patients, metformin treatment significantly decreased the number of aberrant crypt foci compared to the untreated group with a follow-up of 1 month. In our study, HT29 cells were treated with graded concentrations of metformin, 10 mM/25 mM/50 mM, for 24/48 hours. We performed immunofluorescence experiments by means of confocal microscopy and Western blot analysis to evaluate a panel of factors involved in apoptotic/autophagic processes and oxidative stress response. Moreover, HT29 cells treated with metformin were analyzed by flow cytometry assay to detect the cell apoptosis rate. The results demonstrate that metformin exerts growth inhibitory effects on cultured HT29 cells by increasing both apoptosis and autophagy; moreover, it affects the survival of cultured cells inhibiting the transcriptional activation of nuclear factor E2–related factor 2 (NRF-2) and nuclear factor–kappa B (NF-κB). The effects of metformin on HT29 cells were dose- and time-dependent. These results are very intriguing, since metformin is emerging as a multifaceted drug: it has a good safety profile and is associated with low cost, and it might be a promising candidate for the prevention or treatment of colorectal cancer.
ARTICLE | doi:10.20944/preprints202302.0227.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Parkinson’s Disease; MPP+; Neuroinflammation; Oxidative Stress Proinflammatory cytokines
Online: 14 February 2023 (03:18:57 CET)
Parkinson’s disease is a neurodegenerative disorder characterized by oxidative stress and immune activation in the nigro-striatal pathway. Simvastatin regulates cholesterol metabolism and protects from atherosclerosis disease. Simvastatin or tween-80 was administered 7 days before sterotaxic intrastriatal administration of MPP+ (1-methyl-4-phenylpyridine) in rats. Fluorescent lipidic product formation, dopamine levels, and circling behavior were considered damage markers. Twenty-four h and six days after, the animal group lesioned with MPP+ showed significant damage in relation to the control group. Animals pretreated with simvastatin reduced significantly the MPP+-induced damage compared to MPP+ treated group. As apoptosis promotes neuroinflammation and neuronal degeneration in Parkinson’s disease, and since there is not currently a proteomic map of the Nigro striatum of rats, and assuming a high homology among the identified proteins in other rat tissues, we based the search for rat protein homologs related to the establishment of inflammation response. We demonstrate that most proteins related to inflammation are decreased in the simvastatin-treated rats. Furthermore, differential expression of antioxidant enzymes in striated tissue of rat brains was found in response to simvastatin. These results suggest that simvastatin could prevent striatal MPP+-induced damage and for the first time the molecular mechanisms involved in this protective effect.
REVIEW | doi:10.20944/preprints202301.0515.v2
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: antioxidant supplements; ROS; oxidative stress analysis; metabolic diseases
Online: 30 January 2023 (02:46:04 CET)
Cells produce reactive oxygen species (ROS) as by-products of metabolism, which can give rise to a two-sided effect on the body under balanced and imbalanced oxidant homeostasis conditions. Antioxidant supplements exert their beneficial efficacy in the treatment of metabolic diseases only when the oxidant homeostasis is imbalanced with the over-production of ROS. Over-supplementation of antioxidant(s) can also cause an imbalanced oxidant homeostasis to exert detriments to the induction of metabolic diseases. This commentary raises a concern that prior to precise supplementation of antioxidants, an establishment of oxidant homeostasis status is required in avoiding an imbalanced oxidant homeostasis in vivo. In searching for valid oxidant stress makers, 3-Nitrotyrosine seems to fit in with the selection criteria and its quantification can be correlated with the degree of oxidative stress in vivo.
ARTICLE | doi:10.20944/preprints202212.0449.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: redox system; cryptococcal meningitis; oxidative stress; ergosterol; resistance
Online: 23 December 2022 (07:56:36 CET)
Cryptococcus neoformans threaten the health, causing cryptococcal meningitis and pneumonia, especially in immunosuppressed patients, which can be fatal. Recently, our research group evaluated and studied the mechanisms of action of four synthetic peptides (SP) against C. neoformans. Here, in silico and in vitro analyses help deepen understanding of peptides' mechanisms of action. The interaction of the peptides with a membrane receptor was analyzed by docking analysis, in addition to ROS overproduction and the modulation of redox metabolism, inhibition of ergosterol biosynthesis, and release of cytochrome c. Out of four, three peptides interacted with membrane receptor PHO36 altering its structure and function and leading to a higher accumulation of O₂- and H2O2. C. neoformans cells treated with SP presented a reduction in the activity of antioxidant enzymes, corroborating ROS accumulation. However, in the presence of the antioxidant ascorbic acid, some peptides could not induce this oxidative stress and have the activity against C. neoformans affected. Curiously, two of these SPs still maintained the activity against C. neoformans and even induced the membrane pore formation as revealed by propidium iodide uptake assay, revealing their mechanism of action is ROS-independent. Additionally, SPs inhibited the biosynthesis of ergosterol, which corroborates the pore formation on the membrane of C. neoformans cells, inhibited the lactate dehydrogenase activity affecting the cell metabolism, and induced the release of Cyt c from the mitochondria inducing death by apoptosis in the cryptococcal cells. Our findings strongly suggest that SPs act by multiple mechanisms, making it difficult for C. neoformans to acquire resistance highlighting the potential of SPs as alternative molecules in treating infections caused by C. neoformans.
ARTICLE | doi:10.20944/preprints202210.0145.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: oxidative stress; Xenopus laevis; eggs; overactivation; cell death
Online: 11 October 2022 (07:08:01 CEST)
Excessive activation of frog eggs (overactivation) is a pathological process that renders eggs unfertilizable. Its physiological inducers are unknown. Previously, oxidative stress was shown to cause time- and dose-dependent overactivation of Xenopus laevis frog eggs . Here, we demonstrate that the oxidative stress-induced egg overactivation is a calcium-dependent phe-nomenon which can be attenuated in the presence of the selective calcium chelator BAPTA. Degradation of cyclin B2, which is known to be initiated by calcium transient in fertilized or parthenogenetically activated eggs, can also be observed in the overactivated eggs. Decline in mitochondrial membrane potential, ATP depletion and termination of protein synthesis manifest in the eggs within one hour of triggering overactivation. These intracellular events occur in the absence of caspase activation. Furthermore, plasma membrane integrity is compromised in the overactivated eggs, as evidenced by ATP leakage and egg swelling. In sum, our data demonstrate that oxidative stress-induced overactivation of frog eggs causes fast and dramatic disruption of cellular homeostasis, resulting in robust and expedited cell death by a calcium-dependent non-apoptotic mechanism.
REVIEW | doi:10.20944/preprints202206.0257.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: Western diet; oxidative stress; cardiomyocyte; micronutrients; dietary fat
Online: 20 June 2022 (03:38:07 CEST)
Heart failure (HF) has become a public health problem, but exact pathophysiology is still unknown. Western diet characterised with high sugar, high fat, red meat and processed meat, eggs, fried foods and sweetened beverages, may cause oxidative stress and inflammation, leading to oxidative dysfunction and adverse effects on cardiac-ultra-structure. However, only little is known about oxidative function of the of the myocardium and how oxidative dysfunction predispose Ca-overloading resulting in to physio-pathological remodelling leading to HF. Antioxidants such as flavonoids and polyphenolics, omega-3 fatty acids, vitamins, minerals as well as essential and nonessential amino acids that are rich in Indo-Mediterranean type of diets, may have protective roles in maintaining oxidative functions of the heart. The cardiac cells use fatty acids and glucose for the metabolic functions depending upon physiological and metabolic requirements. Apart from glucotoxicity, lipotoxicity is also damaging to cardiac cells which worsen in presence of deficiency of endogenous antioxidants and lower exogenous antioxidants in the diet. There is increased production of ceramide, advanced glycation end products (AGE) and triamino-methyl-N-oxide (TMAO) due to high sugar and high fat diets, leading to oxidative dysfunction and Ca-overloading. The biological changes may begin with physiological remodelling to pathological remodelling due to oxidative damages. High fat diet in combination with inducible nitric oxide synthase (NOSi) via N-arginine methyl ester has been found to preserve ejection fraction in a mouse model of HF. It is possible that increased supplementation of High Exogenous Antioxidant Restorative Treatment (HEART) diet; polyphenolics and flavonoids, vitamins, minerals, arginine, with omega-3 fatty acids, and cessation of red meat and egg may further improve the oxidative function of cardiac cells, resulting in the prevention and improvement in the earliest of the Six Stages of HF. Cohort studies and randomised, controlled trials would be necessary for demonstration of the role of HEART diet in the management of HF.
ARTICLE | doi:10.20944/preprints202111.0578.v1
Subject: Medicine And Pharmacology, Hematology Keywords: DPI; Mitochondria; Leukaemia; Oxidative stress; OxPhos; Ara-C
Online: 30 November 2021 (21:37:18 CET)
Acute myeloid leukaemia (AML) is characterized by the accumulation of undifferentiated blast cells in the bone marrow and blood. In most AMLs, relapse frequently occurs due to resistance to chemotherapy. Compelling research results indicate that drug resistance in cancer cells is highly dependent on the intracellular levels of reactive oxygen species (ROS). Modulating ROS levels is therefore a valuable strategy to overcome the chemotherapy resistance of leukemic cells. In this study, we evaluated the efficiency of diphenyleneiodonium (DPI), a well-known inhibitor of ROS production, in targeting AML cells. Results showed that although inhibiting cytoplasmic ROS production, DPI triggered an increase in the mitochondrial ROS levels caused by the disruption of the mitochondrial respiratory chain. We also demonstrated that DPI blocks the mitochondrial oxidative respiration (OxPhos) in a dose-dependent manner and that AML cells with high OxPhos status were highly sensitive to treatment with DPI, which synergizes with the chemotherapeutic agent cytarabine (Ara-C). Thus, our results suggest that targeting mitochondrial function by DPI might be exploited to target AML cells with high OxPhos status.
ARTICLE | doi:10.20944/preprints202106.0513.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: dementia; neurocognition; neuroimmune; oxidative stress; antioxidants; psychiatry; ageing
Online: 21 June 2021 (13:58:41 CEST)
Background: No studies have examined whether interactions between the apolipoprotein E4 (ApoE4) allele and peripheral biomarkers, hypertension, and type 2 diabetes mellitus (T2DM) may impact the neurocognitive, behavioral and social dysfunctions in amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD). Aims: To clinically define and biologically validate a subgroup of aMCI subjects that take up an intermediate position between controls and AD patients. Methods: In 61 healthy controls, 60 subjects with aMCI, and 60 AD patients we measured the features of aMCI/AD using the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD). A composite BIORISK score was computed using the ApoE4 allele, serum folate, albumin, white blood cells, fasting blood glucose (FBG), atherogenic index of plasma (AIP), T2DM and hypertension. Results: Clustering and nearest neighbour analyses were unable to validate the aMCI subgroup. We constructed two z unit-based composite scores, the first indicating overall burden of cognitive, social, and behavioural deterioration (OBD), and a second reflecting the interactions between ApoE4, all other biomarkers, hypertension and T2DM (BIORISK). We found that 40.2% of the variance in the OBD score was explained by BIORISK, ApoE4, age and education. The OBD index was used to construct three subgroups (normal, medium, and high OBD) with the medium group (n=45) showing mild cognitive dysfunctions (MCD) in memory, language, orientation, and ADL. People with MCD show OBD and BIORISK scores that are significantly different from controls and AD.Conclusions: Petersen’s aMCI criteria cannot be validated and should be replaced by the more restrictive, biologically validated MCD class.
ARTICLE | doi:10.20944/preprints202102.0543.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: depression; metabolic syndrome; probiotics; microbiota; inflammation; oxidative stress
Online: 24 February 2021 (11:20:26 CET)
There is a huge need to search for new treatment options and potential biomarkers of therapeutic response to antidepressant treatment. Depression and metabolic syndrome often coexist while pathophysiological overlap, including microbiota changes, may play a role. The aim of the study is to assess the effect of probiotic supplementation on symptoms of depression, anxiety and stress, metabolic parameters, inflammation and oxidative stress markers, and faecal microbiota in adult patients with depressive disorders depending on the co-occurance of MetS. The trial will be a four-arm, parallel group, prospective, randomized, double-blind, controlled design that will include 200 participants and will last 20 weeks. The probiotic preparation will contain Lactobacillus helveticus Rosell®-52, Bifidobacterium longum Rosell®-175. We will assess the level of depression, anxiety and stress, quality of life, blood pressure, body mass index and waist circumference, white blood cells count, serum levels of C-reactive protein, HDL cholesterol, triglicerides, fasting glucose, faecal microbiota composition and the level of some faecal microbiota metabolites, as well as inflammation markers and oxidative stress parameters in serum. The trial may establish a safe and easy-to-use treatment option as an adjunct in a subpopulation of depressive patients only partially responsive to pharmacologic treatment. (ClinicalTrials.gov identifier: ).
REVIEW | doi:10.20944/preprints202011.0066.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: polyphenols; autophagy; mechanisms; oxidative stress; inflammation; disease models
Online: 2 November 2020 (17:30:15 CET)
Polyphenols represent a group of secondary metabolites of plants which have been analyzed as potent regulators of multiple biological processes, including cell proliferation, apoptosis and autophagy, among others. These natural compounds exhibit beneficial effects and protection against inflammation, oxidative stress and related injuries including metabolic diseases, such as cardiovascular damage, obesity and diabetes and neurodegeneration. In the present review, we report the main biological effects in relationship to autophagy regulation in response to different dietary polyphenols and its impact on metabolic and neurodegenerative diseases
ARTICLE | doi:10.20944/preprints202007.0347.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Calcium; α-klotho; inflammation; oxidative stress; antioxidants; biomarkers
Online: 16 July 2020 (10:49:20 CEST)
Patients with transfusion-dependent thalassemia (TDT) show disorders in calcium metabolism. The α-klotho protein is predominantly expressed in tissues that are involved in calcium homeostasis, and lowered levels are associated with bone disease. Aim of the study. To study the associations between low α-klotho status and calcium metabolism in relation to iron status in children with TDT. Methods. α-klotho, calcium, parathyroid hormone (PTH), calcyphosin, vitamin D3, phosphorous, fibroblast growth factor receptor 2 (FGFR2), as well as iron and erythron biomarkers were measured in 60 children with TDT and 30 healthy control children. Results. A meaningful part of TDT patients showed lowered α-klotho levels, and those children also showed low serum total and ionized calcium concentrations. TDT patients showed increased PTH, FGFR2, and calcyphosin and lowered vitamin D3 as compared with healthy children. The α-klotho levels were significantly correlated with total and ionized calcium (positively) and with iron overload biomarkers and the number of blood transfusions (inversely). Partial Least Squares path analysis showed that 40.1% of the variance in serum total calcium could be explained by the regression on α-klotho, vitamin D3 (both positively), and calcyphosin (inversely) and that the effects of the latter are mediated by iron overload and the number of blood transfusions. Conclusion. In TDT, iron overload and its consequences may induce lowered levels of α-klotho which in turn may lead to lower calcium thereby explaining at least in part the effects of TDT on bone metabolism including spontaneous pathological fractures, osteoporosis, osteopenia, and skeletal deformities.
ARTICLE | doi:10.20944/preprints202007.0260.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: unstable angina; atherogenicity; inflammation; antioxidants; oxidative stress; biomarkers
Online: 12 July 2020 (15:11:16 CEST)
Background: Aberrations in endothelial cells, immune and oxidative pathways are associated with atherosclerosis (ATS) and unstable angina (UA). The role of trace elements, minerals, and the endogenous opioid system (EOS) in UA are less well established. Methods: We measured lipid, insulin resistance (IR), and immune, trace element (copper and zinc), mineral (magnesium, calcium), EOS (β-endorphin and mu-opioid receptor (MOR)) and antioxidant (vitamin D3) biomarkers in patients with ATS (n=60) and UA (n=60) and healthy controls (n=58). Results: ATS patients showed increased atherogenic and IR indices, IL-6, IL-10, β-endorphin, copper and magnesium, and lower zinc than healthy controls. Logistic regression showed that UA was significantly discriminated from ATS without UA with an accuracy of 85.5% using calcium, IL-10, β-endorphin, MOR, triglycerides, IR (all positively), and copper and vitamin D3 (inversely). Neural networks showed that UA was discriminated from ATS without UA with an area under the ROC curve of 0.942 using MOR, β-endorphin, calcium, insulin resistance, vitamin D3 and copper as input variables. We found that 50.0% of the variance in IR was explained by the regression on copper, IL-10, IL-6 (all positively), and zinc (inversely), while 32.9% of the variance in the atherogenic index of plasma was explained by copper, IL-10 (both positively), and magnesium (inversely). Conclusion: UA is not only mediated by insulin resistance, atherogenicity, and immune disorders, but also by aberrations in the endogenous opioid system and trace elements as well as lowered antioxidant levels. Copper appears to play a key role in IR and atherogenicity.
REVIEW | doi:10.20944/preprints202002.0084.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: depression; leaky gut; microbiota; cytokines; neuroimmunomodulation; oxidative stress
Online: 6 February 2020 (10:30:36 CET)
There is robust evidence that major depression (MDD) is accompanied by a low-grade activation of the immune-inflammatory response system, which is involved in the pathophysiology of this disorder. It is also becoming apparent that glia cells are in reciprocal communication with neurons and orchestrate various neuromodulatory, homeostatic, metabolic, and immune mechanisms and have a crucial role in neuroinflammatory mechanisms in MDD. Those cells mediate the central nervous system (CNS) response to systemic inflammation and psychological stress, but at the same time, they may be an origin of the inflammatory response in the CNS. The sources of activation of the inflammatory response in MDD are immense, however, in recent years, it is becoming increasingly evident that the gastrointestinal tract with gut-associated lymphoid tissue (GALT) and increased intestinal permeability to bacterial LPS and food-derived antigens contribute to activation of low-grade inflammatory response with subsequent psychiatric manifestations. Furthermore, an excessive permeability to gut-derived antigenic material may lead to subsequent autoimmunities which are also known to be comorbid with MDD. In this chapter, we discuss fascinating interactions between the gastrointestinal tract, increased intestinal permeability, intestinal microbiota, and glia-neuron crosstalk, and their roles in the pathogenesis of the inflammatory hypothesis of MDD. To emphasize those crucial intercommunications for the brain functions, we propose the term of microbiota-gut-immune-glia (MGIG) axis.
ARTICLE | doi:10.20944/preprints202001.0285.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: oxidative stress; neuroimmunomodulation; major depression; inflammation; neurotoxicity; schizophrenia
Online: 24 January 2020 (14:46:17 CET)
Oxidative stress toxicity (OSTOX), as well as lowered antioxidant defenses (ANTIOX), play a role in temporal lobe epilepsy (TLE). Nevertheless, the associations between OSTOX/ANTIOX and psychiatric comorbidities in TLE are largely unknown.Thus, this study examines plasma malondialdehyde (MDA), lipid hydroperoxides (LOOH), advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), total radical trapping antioxidant parameter (TRAP) and sulfhydryl (-SH) groups in Depression due to TLE (n=25); Anxiety Disorders due to TLE (n=27); Psychotic Disorder due to TLE (n=25); “pure TLE” (n=27); and healthy controls (n=40).TLE and mesial temporal sclerosis (MTS) were characterized by significant increases in OSTOX (MDA, AOPP, LOOH) and lowered ANTIOX (-SH groups, TRAP). The discrimination of pure TLE from controls yielded a significant area under the ROC curve for MDA (0.999), AOPP (0.851), -SH groups (0.899) and the OSTOX/ANTIOX ratio (0.996). Seizure frequency is significantly associated with increased MDA and lowered LOOH and NOx levels. Increased MDA was associated with the severity of depressive and physiosomatic symptoms, whilst increased AOPP levels predicted suicidal ideation. Depression and anxiety disorders co-occurring with TLE showed significantly lower MDA levels than TLE without any comorbidities. The psychotic and negative symptoms of TLE are associated with increased MDA levels and excitation with increased LOOH and lowered TRAP levels.These results indicate that oxidative stress toxicity especially protein oxidation and aldehyde formation coupled with lowered -SH groups play a key role in the pathophysiology of TLE/MTS. Increased aldehyde formation also impacts psychopathology, psychosis, as well as negative and depressive symptoms.
ARTICLE | doi:10.20944/preprints201912.0280.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: aerobic glycolysis; caveolin1; hypoxia; monocrotaline; oxidative phosphorylation; RhoA
Online: 21 December 2019 (10:48:00 CET)
Pulmonary hypertension (PH) is a serious disorder with high morbidity and mortality rate. We analyzed the right ventricular systolic pressure (RVSP), right ventricular hypertrophy (RVH), lung histology and transcriptomes of six weeks old male rats with PH induced by: 1) hypoxia (HO), 2) administration of monocrotaline (CM) or 3) administration of monocrotaline and exposure to hypoxia (HM). The results in PH rats were compared to those in control rats (CO). After four weeks exposure, increased RVSP and RVH, pulmonary arterial wall thickening, and alteration of the lung transcriptome were observed in all PH groups. The HM group exhibited the largest alterations and also neointimal lesions and obliteration of lumen in small arteries. We found that the PH increased the expression of caveolin1, matrix metallopeptidase 2 and numerous inflammatory and cell proliferation genes. The cell-cycle, vascular smooth muscle contraction and the oxidative phosphorylation pathways, as well as their interplay were largely perturbed. Our results also suggest that the up-regulated Rhoa (ras homolog family member A) mediates its action through expression coordination with several ATPases. The upregulation of antioxidant genes and the extensive mitochondrial damage observed especially in HM group, indicate metabolic shift towards aerobic glycolysis.
REVIEW | doi:10.20944/preprints201912.0012.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: premenstrual; depression; inflammation; neuro-immune; oxidative stress; antioxidants
Online: 2 December 2019 (14:12:33 CET)
Premenstrual syndrome (PMS) frequently occurs in women of childbearing age. There are different case definitions of PMS, one proposed by the American College of Obstetricians and Gynecologists (ACOG) and another based on the Daily Record of Severity of Problems (DRSP) scores. Here we review our recent papers indicating that the discovery of biomarkers of menstrual cycle-related symptoms is strongly dependent on the case definitions used and that the gold standard methods used to asses PMS, including the ACOG case definition, induce a high degree of false-negative findings. We propose a new case definition of the menstrual cycle-associated syndrome (MCAS), which is characterized by increased DRSP scores during the menstrual cycle and additionally by an exaggerated increase in symptoms the week prior to the menses. This case definition performed well and was externally validated by diverse biomarkers including plasma levels of progesterone and estradiol, chemokines (e.g. CCL2, CCL5 and CCL11), epidermal growth factor, hydroperoxides, paraoxonase 1 activity and complement C4. In conclusion, when evaluating menstrual cycle-related symptoms and their associations with biomarkers, we propose to assess daily measurements of the DRSP and based on those scores to a) use the diagnosis of MCAS as an indicant of menstrual cycle-related symptoms; and b) examine the associations of the time series in the DRSP and its subdomains (e.g. depression, physio-somatic, anxiety) and those in biomarkers including distributed lag models.
REVIEW | doi:10.20944/preprints201909.0344.v1
Subject: Medicine And Pharmacology, Veterinary Medicine Keywords: horses; spermatozoa; ROS; oxidative stress; redox regulation; equine
Online: 30 September 2019 (08:06:46 CEST)
Redox regulation and oxidative stress have become areas of major interest in spermatology. Alteration of redox homeostasis is recognized as a significant cause of male factor infertility and is behind the damage that spermatozoa experience after freezing and thawing or conservation in a liquid state. While for a long time, oxidative stress was just considered an overproduction of ROS, nowadays it is considered as a consequence of redox deregulation. Many essential aspects of spermatozoa functionality are redox regulated, with reversible oxidation of thiols in cysteine residues of key proteins acting as an “on-off” switch controlling spermatic function. However, if deregulation occurs, these residues may experience irreversible oxidation and oxidative stress leading to spermatic malfunction and ultimately death. Stallion spermatozoa are “professional producers” of ROS due to their intense mitochondrial activity, and thus sophisticated systems to control redox homeostasis are also characteristic of this species. As a result, combined with the fact that embryos can easily be collected in this species, horses are a good model for the study of redox biology in the spermatozoa and its impact on the embryo.
ARTICLE | doi:10.20944/preprints201909.0033.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: depression; cytokines; neuro-immune; inflammation; oxidative stress; antioxidants
Online: 3 September 2019 (16:20:18 CEST)
Beta-thalassemia major (β-TM) patients are treated with repeated blood transfusions, which may cause iron overload (IO), which in turn may induce immune aberrations. Patients with β-TM have an increased risk of major depressive disorder (MDD). The aims of the present study are to examine whether repeated blood transfusions, IO and immune-inflammatory responses are associated with MDD in children (6-12 years) with β-TM. The Children’s Depression Inventory (CDI), iron status (serum iron, ferritin, transferrin, TS%) and serum levels of CCL11, IL-1β, IL-10, and TNF-α were measured in β-TM with (n=54) and without (n=57) MDD and in healthy children (n=55). The results show that MDD in β-TM is associated with a greater number of blood transfusions, increased IO and IL-1β levels. Partial Least Squares path analysis shows that 68.8% of the variance in the CDI score is explained by the number of blood transfusions, IO, and increased levels of IL-1β and TNF-α. The latter two cytokines partly mediate the effects of IO on the CDI score, while the effects of blood transfusions on the CDI score are partly mediated by IO and the path from IO to immune activation. IO is also associated with increased IL-10 and lower CCL11 levels but these alterations are not significantly associated with MDD. In conclusion, blood transfusions may be causally related to MDD in β-TM children and their effects are in part mediated by increased IO and the consequent immune-inflammatory response. The results suggest that not only IO and its consequences including inflammation and ferroptosis, but also other factors related to the number of transfusions may cause MDD including psychosocial stressors. Current treatment modalities with folic acid and vitamin C are insufficient to attenuate IO and immune-inflammatory responses and to prevent MDD is children with β-TM undergoing blood transfusions.
ARTICLE | doi:10.20944/preprints201908.0296.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: oxidative stress; antioxidative system; Brassicaceae family; heavy metals
Online: 28 August 2019 (14:43:10 CEST)
Metal hyperaccumulating plants should have extremely efficient defence mechanisms, enabling growth and development in a polluted environment. Brassica species are known to display hyperaccumulation capability. Brassica juncea (Indiana mustard) v. Malopolska plants were exposed to trace elements, i.e., cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn), at a concentration of 50 M and were then harvested after 96 hours for analysis. We observed a high index of tolerance (IT), higher than 90%, for all B. juncea plants treated with the four metals, and we showed that Cd, Cu, Pb and Zn accumulation was higher in the above-ground parts than in the roots. We estimated the metal effects on the generation of reactive oxygen species (ROS) and the levels of protein oxidation as well as on the activity and gene expression of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). The obtained results indicate that organo-specific ROS generation was higher in plants exposed to essential metal elements (i.e., Cu and Zn), compared with non-essential ones (i.e., Cd and Pb), in conjunction with SOD, CAT and APX activity and expression at the level of encoding mRNAs and existing proteins. In addition to the potential usefulness of B. juncea in the phytoremediation process, the data provide important information concerning plant response to the presence of trace metals.
ARTICLE | doi:10.20944/preprints201908.0044.v1
Subject: Biology And Life Sciences, Biophysics Keywords: hypertensive nephropathy; oxidative stress; fibrosis; inflammation; Cx43; Fasudil
Online: 5 August 2019 (05:02:36 CEST)
In various models of chronic kidney disease, the amount and localization of Cx43 in the nephron is known to increase, but the intracellular pathways that regulate these changes have not been identified. Therefore, we proposed that: "In the model of renal damage induced by infusion of angiotensin II (AngII), a RhoA/ROCK-dependent pathway, is activated and regulates the abundance of renal Cx43”. In rats, we evaluated: 1) the time-point where the renal damage induced by AngII is no longer reversible; and 2) the involvement of a RhoA/ROCK-dependent pathway and its relationship with the amount of Cx43 in this irreversible stage. Systolic blood pressure (SBP) and renal function (urinary protein/urinary creatinine: Uprot/UCrea) were evaluated as systemic and organ outcomes, respectively. In kidney tissue, we also evaluated: 1) oxidative stress (amount of thiobarbituric acid reactive species), 2) inflammation (immunoperoxidase detection of the inflammatory markers ED-1 and IL-1β), 3) fibrosis (immune detection of type III collagen; Col III) and 4) activity of RhoA/ROCK (amount of phosphorylated MYPT1; p-MYPT1). The ratio Uprot/UCrea, SBP, oxidative stress, inflammation, amount of Cx43 and p-MYPT1 remained high 2 weeks after suspending AngII treatment in rats treated for 4 weeks with AngII. These responses were not observed in rats treated with AngII for less than 4 weeks, in which all measurements returned spontaneously close to the control values after suspending AngII treatment. Rats treated with AngII for 6 weeks and co-treated for the last 4 weeks with Fasudil, an inhibitor of ROCK, showed high SBP but did not present renal damage or increased amount of renal Cx43. Therefore, renal damage induced by AngII correlates with the activation of RhoA/ROCK and the increase in Cx43 amounts and can be prevented by inhibitors of this pathway.
ARTICLE | doi:10.20944/preprints201904.0178.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: anti-oxidative properties; DPPH; grape marmalade; lactobacillus; probiotics
Online: 16 April 2019 (10:27:52 CEST)
Grape foods fermented with probiotics are sources of beneficial bacteria for the GI tract and also have a high antioxidant capacity. The addition of probiotics to ferment food has always been a traditional process; therefore, probiotic dairy and non-dairy products might contribute to a daily antioxidant diet to improve consumers’ life quality and health. This research was undertaken to determine the viability of 4 wild isolates of Lactobacillus for storage at 5 and 25ºC within 90 days in simulated synthetic grape media and a standard grape marmalade formulation. Changes in active culture numbers, pH level, glucose concentration, and antioxidant properties were evaluated. Most of the isolates demonstrated higher growth in the grape marmalade than the synthetic grape marmalade, which was greater than 7 Log cfu/g within 90 days of storage at 5ºC. In addition, most of the wild isolates grew beyond the critical count of 106 cfu/g in sampling between 60 and 90 days of storage. Moreover, fermented grape marmalade with probiotics showed a strong antioxidant capacity that failed to differ significantly with the synthetic medium. The study confirmed L. paraplantarum, L. plantarum, W. paramesenteroides, and E. feacalis were ideal probiotics for fermentation process of grape marmalade.
ARTICLE | doi:10.20944/preprints201903.0227.v2
Subject: Biology And Life Sciences, Horticulture Keywords: oxidative stress; enzymatic antioxidants; malondialdehyde; membrane permeability; chlorophyll
Online: 28 March 2019 (11:15:50 CET)
Scarcity of water is one of the most serious concerns in plant biology with diverse implications at all the levels of molecular, biochemical, and physiological phenomena of plant growth, development, and consequently the productivity. Most of the strategies to induce or enhance drought tolerance in plants are unreasonably expensive and/or time-consuming. Some studies conducted in the recent past have shown that plant growth regulators (PGRs) may induce/improve physiological tolerance in plants to cope with adverse environmental conditions including drought. The present study was aimed at investigating the effects of foliar spray of GABA (0, 1, 2, and 4 mM) applied 20 days following the germination of seeds, on vegetative growth, morphological characteristics, integrity of cell-membrane, and the levels of photosynthetic pigments and enzymatic antioxidants in carrot cvs. Supertaj and Bharat, grown under 100% and 50% field capacity of soil moisture. The treated and untreated (control) carrot plants were harvested and analyzed 2 weeks following the GABA application. The results revealed that foliar application of GABA improved the vegetative growth and significantly increased the levels of free amino acids, plastid pigments, enzymatic antioxidants, and the relative water content in the root crop grown under 50% field capacity of soil moisture, compared to control. Additionally, the GABA application decreased the electrolyte leakage of ions and melondialdehyde (MDA) content in carrot leaves. The carrots harvested from GABA-treated or untreated (control) plants were not significantly different for their protein contents. In conclusion, the incorporation of GABA in the production management of carrots may help plants to mitigate the adverse effects of water deficit stress.
ARTICLE | doi:10.20944/preprints201810.0488.v2
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: diabetes kidney; oxidative stress; inflammation; resveratrol; insulin signaling
Online: 4 January 2019 (11:43:35 CET)
Background and objectives: Diabetes mellitus is a disease of insulin deficiency or its inability of usage by the target tissues leading to impairment of carbohydrate, lipid, and protein metabolisms. Resveratrol, having robust anti-inflammatory and anti-oxidant properties, has a high potential to treat or prevent the pathogenesis of diseases. This study was conducted to reveal the relationship between diabetes-induced oxidative stress and tissue inflammation with changes in main enzymatic antioxidants (cat, sod, gpx, and gst) and the components of the insulin signaling pathway (insulin Rβ, irs-1, pi3k, akt, mtor) in kidney tissues. Additionally, the effects of resveratrol on these parameters were evaluated. Materials and Methods: Male Wistar rats were randomly divided into four groups; (1) control/vehicle; (2) control/20 mg/kg resveratrol; (3) diabetic/vehicle; (4) diabetic/20 mg/kg resveratrol. Gene and protein expressions of antioxidant enzymes and insulin signaling elements were evaluated in renal tissues. Results: Downregulation of antioxidant enzymes’ gene expression in the kidney tissues of diabetic rats was demonstrated and this situation was devoted partially to the reduced gene expression of nfκb. Moreover, the components of renal insulin signaling elements were upregulated at both gene and protein expression levels in diabetic rats, and resveratrol treatment decreased this sensitization towards the control state. Conclusion: Resveratrol partially improved diabetes-induced renal oxidative stress and inflammation due to healing action on renal antioxidant enzymes and insulin signaling pathway components.
ARTICLE | doi:10.20944/preprints201809.0431.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: hesperidin; L-NAME; cardiovascular remodeling; oxidative stress; inflammation
Online: 21 September 2018 (08:15:47 CEST)
Hesperidin is a major flavonoid isolated from citrus fruits that exhibits several biological activities. This study aims to evaluate the effect of hesperidin on cardiovascular remodeling induced by N-nitro L-arginine methyl ester (L-NAME) in rats. Male Sprague-Dawley rats were treated with L-NAME (40 mg/kg); L-NAME plus hesperidin (15 mg/kg), or hesperidin (30 mg/kg), or captopril (2.5 mg/kg) for five weeks (n = 8/group). Hesperidin or captopril significantly prevented the development of hypertension in L-NAME rats. Moreover, hesperidin or captopril alleviated L-NAME-induced cardiac remodeling; increases in wall thickness, cross sectional area (CSA) and fibrosis of left ventricular (LV), and vascular remodeling; increases in wall thickness, CSA, vascular smooth muscle cells and collagen deposition in the aorta. These were associated with reduced oxidative stress markers, tumor necrosis factor-alpha (TNF-α), transforming growth factor-beta 1 (TGF-β1) and enhancing plasma nitric oxide metabolite (NOx) in L-NAME treated groups. Furthermore, up-regulation of tumor necrosis factor receptor type 1 (TNF-R1) and TGF-β1 protein expression and the over-expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) were suppressed in L-NAME rats treated with hesperidin or captopril. These data suggested that hesperidin had cardioprotective effects in L-NAME hypertensive rats. The possible mechanism may involve its antioxidant and anti-inflammatory effects.
REVIEW | doi:10.20944/preprints201809.0422.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: LDL-oxidation; DNA-damage; antioxidant vitamins; oxidative stress
Online: 20 September 2018 (16:53:42 CEST)
Radical oxygen species formed in human tissue cells by many endogenous and exogenous pathways, cause extensive oxidative damage, which has been linked to various human diseases. This review paper provides an overview of lipid peroxidation and focuses on the free-radicals initiated processes of LDL oxidative modification and DNA oxidative damage, which are widely associated to the initiation and development of atherosclerosis and carcinogenesis, respectively. The article subsequently provides an overview of the recent human trials or even in vitro investigations on the potential of natural antioxidant compounds (such as carotenoids, vitamins C and E) to monitor LDL and DNA oxidative changes.
ARTICLE | doi:10.20944/preprints201805.0398.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: retinal degeneration; DNA methylation; epigenetics; oxidative stress; inflammation
Online: 28 May 2018 (10:33:13 CEST)
The role of epigenetic alterations in the pathogenesis of age-related macular degeneration (AMD) has been pending so far. Our study investigated the effect of oxidative stress and inflammation on DNA methyltransferases (DNMTs) and Sirtuin 1 (SIRT1) functions, as well as on long interspersed nuclear element-1 (LINE-1) methylation, in human retinal pigment epithelial (ARPE-19) cells. Therefore, we evaluated whether treatment with resveratrol may restore changes in LINE-1 methylation by modulating DNMTs and SIRT1 functions. Cells were treated with 25 mU/ml glucose oxidase (GOx) or 10 µg/ml lipopolysaccharide (LPS) to mimic oxidative or inflammatory conditions, respectively. Oxidative stress decreased DNMT1, DNMT3a, DNMT3b and SIRT1 expression (p-values <0.05), as well as total DNMTs (-28.5%; p<0.0001) and SIRT1 (-29.0%;p<0.0001) activities. Similarly, inflammatory condition decreased DNMT1 and SIRT1 expression (p-values<0.05), as well as total DNMTs (-14.9%;p=0.007) and SIRT1 (-20.1%;p<0.002) activities. Interestingly, GOx- and LPS-treated cells exhibited lower LINE-1 methylation compared to controls (p-values<0.0001). We also demonstrated that treatment with 10 μM resveratrol for 24 hours counteracted the detrimental effect on LINE-1 methylation via increasing DNMTs and SIRT1 functions in cells upon oxidative and inflammatory conditions. However, further studies should explore the perspectives of resveratrol as a suitable strategy for the prevention and/or treatment of AMD.
ARTICLE | doi:10.20944/preprints201611.0093.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: diabetes mellitus; cardiomyopathy; hyperglycemia; oxidative stress; aspalathin; Nrf2
Online: 17 November 2016 (11:07:56 CET)
Aspalathin (ASP) can protect H9c2 cardiomyocytes against high glucose (HG)-induced shifts in myocardial substrate preference, oxidative stress and apoptosis. While the protective mechanism of aspalathin remains unknown, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged as a key factor for intracellular responses against oxidative stress. Therefore, we hypothesized that aspalathin protects the myocardium against hyperglycemia-induced oxidative damage by up-regulating Nrf2 expression in H9c2 cardiomyocytes and diabetic (db/db) mice. Using an oxidative stress RT2 Profiler PCR array, ASP at a dose of 1 µM was demonstrated to protect H9c2 cardiomyocytes against HG-induced oxidative stress, but silencing of Nrf2 abolished this protective response of ASP and exacerbated cardiomyocyte apoptosis. Db/db mice and their non-diabetic (db/+) littermate controls were subsequently treated daily for 6 weeks with either a low (13 mg/kg) or high (130 mg/kg) ASP dose. Compared to nondiabetic mice the db/db mice presented increased cardiac remodeling and enlarged left ventricular wall that occurred concomitant to enhanced oxidative stress. Daily treatment of mice with ASP at a dose of 130 mg/kg for 6 weeks was more effective at reversing complications than both a low dose ASP or metformin, eliciting enhanced expression of Nrf2 and its downstream antioxidant genes. These results indicate that ASP maintains cellular homeostasis and protects the myocardium against hyperglycemia-induced stress through activation of Nrf2 and its downstream target genes.
ARTICLE | doi:10.20944/preprints201608.0011.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: curcumin; furazolidone; oxidative stress; DNA damage; mitochondrial pathway
Online: 2 August 2016 (05:59:38 CEST)
Furazolidone (FZD) is a synthetic nitrofuran with the antiprotozoal and antibacterial activity. The proper mechanism of FZD induced toxicity is still unclear. This study aimed to investigate the protective effect of curcumin on FZD induced oxidative stress, DNA injury and apoptosis in human hepatocyte L02 cells. The results showed that curcumin treatment significantly ameliorated FZD induced cytotoxicity, characterized by decreasing the production of reactive oxygen species (ROS) and malondialdehyde, as well as increasing superoxide dismutase, catalase activities and glutathione contents. Moreover, curcumin pretreatment significantly inhibited FZD induced the loss of mitochondrial membrane potential, the activation caspase-9 and -3 and apoptosis. Comet assay showed that curcumin attenuated FZD induced DNA injury in a dose-dependent manner. Correspondingly, curcumin markedly reversed the up-regulation of p53, Bax, caspase-9 and -3 mRNA expressions and the down-regulation of Bcl-2 mRNA (all p<0.05 or 0.01). These results reveal that curcumin protects against FZD induced oxidative stress, DNA injury and cell apoptosis via inhibiting oxidative stress and mitochondrial pathway, which may be attributed to ROS scavenging and anti-oxidative ability of curcumin. Importantly, our study highlights that curcumin may be a potential way to prevent FZD-mediated oxidative DNA injury and apoptosis in human or animals.
ARTICLE | doi:10.20944/preprints202301.0100.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Antarctic fish; antioxidant enzymes; oxidative stress; gene expression; PFAS
Online: 5 January 2023 (04:50:42 CET)
Antarctica is the continent with the lowest local human impact, yet it is still vulnerable to contaminants coming from external sources. Emerging pollutants, like PFAS, pose an increasing threat to this environment and therefore require more in-depth investigations to understand their environmental fate and biological impacts. The present study, part of the AntaGPS project, focuses on expression analysis at the transcriptional level of genes coding for 4 antioxidant enzymes (sod1, sod2, gpx1, gpx4) in different organs of an Antarctic fish species, Trematomus newnesi. The kidney showed a higher level of expression than the liver of wildlife specimens. The mRNA levels were also assessed in fish exposed to 1.5 μg/L of PFOA for 10 days. In the liver, the treatment induced an increase in gene expression for all the considered enzymes, while in the kidney it induced a general decrease. The obtained results constitute a starting point for using the expression of antioxidant enzymes as biomarkers, both of oxidative stress and exposure to PFAS, in future biomonitoring campaigns in the Antarctic marine environment.
REVIEW | doi:10.20944/preprints202211.0350.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Proteomics, Age-related macular degeneration, inflammation, biomarker, oxidative stress.
Online: 21 November 2022 (02:35:09 CET)
Age-related macular degeneration (AMD) is a common ocular disease characterized by the de-generation of the central area of the retina in elderly population. Progression and response to treatment is influenced by genetic and non-genetic factors. Proteomics is a powerful tool to study, at the molecular level, the mechanisms underlaying the progression of the diseases, to identify new therapeutical targets and to establish biomarkers to monitor progression and treatment ef-fectiveness. In this work we pursue to systematically review the use of proteomic-based ap-proaches for the study of the molecular mechanisms underlying the development of AMD, as well as the progression of the disease and the on-treatment patient monitoring. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines were followed. Proteomic approaches have identified key players on the onset of the disease, such as proteins involved in lipid metabolism and oxidative stress, but also in the progression to advanced stages, including factors related to extracellular matrix integrity and angiogenesis. Although an-ti-vascular endothelial growth factor (anti-VEGF)-based therapy has been crucial in the treatment of neovascular AMD it is necessary to get deeper into the underlying disease mechanisms to move forward to next-generation therapies of the later-stage forms of this multifactorial disease.
REVIEW | doi:10.20944/preprints202208.0468.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: esculetin; cancer; oxidative stress; inflammation; arthritis; diabetes; fatty liver
Online: 29 August 2022 (05:25:05 CEST)
Esculetin is a coumarin compound, which belongs to the class of benzopyrone enriched in various plants such as Sonchus grandifolius, Aesculus turbinata, and many others. Glycosides and caffeic acid conjugates are the common forms of esculetin present in medicinal plants. Esculetin acts as an antioxidant, anti-inflammatory, anti-diabetic, anti-hepatic, and anti-cancer agent by inhibiting the production of free radicals, inflammatory mediators, and genes that cause liver diseases and cancer. It also aids in the regulation of blood sugar. Scientists developing pharmaceutical formulations require some rationale and preliminary studies for drug design, but a small number of clinical studies on humans containing esculetin limit its potential for use as a safe alternative drug. Therefore, in this review article, the published studies have been reviewed to identify the pathogenesis of cancer, oxidative stress, inflammation, arthritis, diabetes and fatty liver along with the discussion on potential therapeutic strategies of esculetin. Advancements in our understanding of these diseases will aid in the development of new and innovative medications for treating many ailments. In conclusion, esculetin has immense potential to be used as a safe drug against many diseases but requires further testing and confirmation through clinical trials.
ARTICLE | doi:10.20944/preprints202205.0154.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: antioxidant enzymes; freshwater fish; oxidative stress; PFAS; Veneto region
Online: 12 May 2022 (02:47:28 CEST)
In recent decades, the interest in PFAS has grown exponentially around the world, due to the toxic effects induced by these chemical compounds in humans, as well as in other animals and in plants. However, current knowledge related to the antistress responses that organisms can express when exposed to these substances is still insufficient and therefore it requires further investigation. The present study focuses on antioxidant responses in Squalius cephalus and Padogobius bonelli, exposed to significant levels of PFAS in an area of the Veneto region subjected to a recent relevant pollution case. These two ubiquitous freshwater species were sampled in three rivers characterized by different concentrations of PFAS. Several biomarkers of oxidative stress have been evaluated and the results suggest that PFAS chronic exposure induces some physiological responses in the target species, at both cellular and tissue scales. The risk of oxidative stress seems to be kept under control by the antioxidant system by means of gene activation at the mitochondrial level. Moreover, the histological analysis suggests an interesting protective mechanism against damage to the protein component based on lipid vacuolization.
ARTICLE | doi:10.20944/preprints202112.0263.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: anti-inflammatory; cytotoxicity; oxidative stress; phenolic compounds; sweet cherries
Online: 16 December 2021 (08:18:44 CET)
Cherries have been largely investigated due to their high content in phenolics in order to fully ex-plore their health-promoting properties. Therefore, this work aimed to assess, for the first time, the anti-inflammatory potential of phenolic-targeted fractions of Saco cherry, using RAW 264.7 mac-rophages stimulated with lipopolysaccharide. Additionally, the cytotoxic effects on gastric ade-nocarcinoma (AGS), neuroblastoma (SH-SY5Y) and normal human dermal fibroblast (NHDF) cells were evaluated, as well as the ability to protect these cellular models against induced oxidative stress. The obtained data revealed that cherry fractions can interfere with cellular nitric oxide (NO) levels by capturing NO radicals and decreasing inducible nitric oxide synthase and cyclooxygen-ase-2 expression. Furthermore, it was observed that all cherry fractions exhibited dose-dependent cytotoxicity against AGS cells, presenting cytotoxic selectivity for these cancer cells when compared to SH-SY5Y and NHDF cells. Regarding their capacity to protect cancer cells against oxidative injury, in most assays, the total cherry extract was the most effective. Overall, this study reinforces the sweet cherries incorporation in new pharmaceutical products, smart foods and nutraceuticals.
ARTICLE | doi:10.20944/preprints202112.0179.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Cyperus rotundus rhizomes; Diabetes; Lipids Profile; Hepatorenalprotective; Oxidative marker
Online: 10 December 2021 (13:11:59 CET)
Objective: The hypoglycemic, hepatorenalprotective, and antioxidant Activities of Cyperus rotundus rhizomes extract in an alloxan-induced diabetic rat model were investigated in this work.Methods: 25 Male rats were divided into 5 groups: normal control, diabetic control, diabetic of C. rotundus (200 mg/kg b.w), diabetic of C. rotundus (400 mg/kg b.w), diabetic of glibenclamide (0.6mg/kg).Treatments were administered orally for 6 weeks.Results: A single injection of alloxan to rats (150mg/kg b.w) caused pathological alterations in all studied parameters and histological structure of the pancreas. On the other hand, results showed that oral administration of C. rotundus rhizomes extract in dose of 200 and 400 mg/kg caused significant reduction in glucose, HbA1C%, α-amylase level and plasma lactate together with significant elevation in serum insulin, serum pyruvate with an improvement in insulin resistance. In line with amelioration of the diabetic state, C. rotundus rhizomes extract improved of the liver and kidney functions, and oxidative marker levels. Moreover, the extract succeeded to reduce the elevated serum total cholesterol, triglyceride (TG) and low-density lipoprotein- cholesterol (LDL-C) levels and to elevate the reduced high-density lipoprotein- cholesterol (HDL-C) level of diabetic rats.Conclusion: The investigation data concluded that C. rotundus rhizomes extract could be used as alternative treatments as antidiabetic, antioxidant and antihyperlipidemic, and agent as well as in liver and kidney protective in alloxan induced-diabetic rats. This may be related to the presence of saponin glycosides, polyphenols, flavonoids, and terpenoids in the ethanolic extract of C. rotundus rhizomes, which was discovered by phytochemical screening in this study to be present in the plant.
ARTICLE | doi:10.20944/preprints202111.0432.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Oxidative and nitrosative stress; antioxidants; biomarkers; neuro-immune; neurocognition
Online: 23 November 2021 (15:05:47 CET)
This study aims to systematically review and meta-analyze the nitro-oxidative stress (O&NS)/antioxidant (ANTIOX) ratio in the peripheral blood of people with mild cognitive impairment (MCI). We searched PubMed, Scopus, Google Scholar, and Web of Science for articles published from inception until July 31, 2021. Forty-six studies on 3.798 MCI individuals and 6.063 healthy controls were included. The O&NS/ANTIOX ratio was significantly higher in MCI than in controls with a Standardized Mean Difference (SMD)=0.378 (95% CI: 0.250; 0.506). MCI individuals showed increased lipid peroxidation (SMD=0.774, 95%CI: 4.416; 1.132) and O&NS-associated toxicity (SMD=0.621, CI: 0.377; 0.865) and reduced glutathione (GSH) defenses (SMD=0.725, 95%CI: 0.269; 1.182) as compared with controls. MCI was also accompanied by significantly increased homocysteine (SMD=0.320, CI: 0.059; 0.581), but not protein oxidation, and lowered non-vitamin (SMD=0.347, CI: 0.168; 0.527) and vitamin (SMD=0.564, CI: 0.129; 0.999) antioxidant defenses. The results show that MCI is at least in part due to increased neuro-oxidative toxicity and suggest that treatments targeting lipid peroxidation and the GSH system may be used to treat or prevent MCI.
REVIEW | doi:10.20944/preprints202107.0361.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: wound healing; oxidative stress; antioxidant dressing; reactive oxygen species.
Online: 15 July 2021 (13:32:15 CEST)
(1) Background: Reactive oxygen species (ROS) play a crucial role in the preparation of the normal wound healing response. Therefore, a correct balance between low or high levels of ROS is essential. Antioxidant dressings that regulate this balance is a target for new therapies. The purpose of this review is to identify the compounds with antioxidant properties that have been tested for wound healing and to summarize the available evidence on their effects. (2) Methods: A literature search was conducted and included any study that evaluated the effects or mechanisms of antioxidants in the healing process (in vitro, animal models, or human studies). (3) Results: Seven compounds with antioxidant activity were identified (Curcumin, N-acetyl cysteine, Chitosan, Gallic Acid, Edaravone, Crocin, Safranal, and Quercetin) and 46 studies reporting the effects on the healing process of these antioxidants compounds were included. (4) Conclusions: These results highlight that numerous novel investigations are being conducted to develop more efficient systems for wound healing activity. The application of antioxidants is useful against oxidative damage and accelerates wound healing. Designing biomaterials that can scavenge excess reactive oxygen species requires new technologies and further research, especially human studies.
REVIEW | doi:10.20944/preprints202105.0533.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: free radicals; oxidative stress; hepatocellular carcinoma; anti-oxidants; kaempferol
Online: 21 May 2021 (17:21:59 CEST)
Keywords: free radicals; oxidative stress; hepatocellular carcinoma; anti-oxidants; kaempferol
ARTICLE | doi:10.20944/preprints202105.0180.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: oxidative stress; nitrosative stress; immune response; inflammation; antioxidants; LPS
Online: 10 May 2021 (11:43:52 CEST)
An immune-inflammatory response is accompanied by increased nitro-oxidative stress. The aims of this mechanistic review are to review: a) the role of redox sensitive transcription factors and enzymes, ROS/RNS production and the activity of cellular antioxidants on the activation and performance of macrophages, dendritic cells, neutrophils, T cells, B cells and natural killer cells; b) the involvement of high-density lipoprotein (HDL), apolipoprotein (Apo)A1, paraoxonase (PON)-1, and oxidized phospholipids in the regulation of the immune response; and c) the detrimental effects of hypernitrosylation and chronic nitro-oxidative stress on the immune response. The redox changes during immune-inflammatory responses are orchestrated by the actions of nuclear factor (NF)-κB, HIF1alpha, the mechanistic target of rapamycin (mTor), the phosphatidylinositol 3‑kinase (PI3K) / protein kinase B (AKT) signalling pathway, mitogen-activated protein (MAP) kinases, 5' AMP-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor (PPAR). The performance and survival of individual immune cells is under redox control and sensitive to intracellular and extracellular levels of ROS/RNS and is heavily influenced by cellular anti-oxidants including the glutathione and thioredoxin systems, nuclear factor erythroid 2-related factor 2 (Nrf-2), and the HDL complex. Chronic nitro-oxidative stress and hypernitrosylation inhibit the activity of those antioxidant systems, the tricarboxylic acid cycle, mitochondrial functions, and the metabolism of immune cells. In conclusion, those redox-associated mechanisms modulate metabolic reprogramming of immune cells, macrophage and T helper cell polarization, phagocytosis, production of pro- versus anti-inflammatory cytokines, immune training and tolerance, chemotaxis, pathogen sensing, antiviral and antibacterial effects, Toll-like receptor activity, and endotoxin tolerance.
REVIEW | doi:10.20944/preprints202101.0606.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: ROS; sources of ROS; oxidative stress; ROS and cancer
Online: 29 January 2021 (09:01:24 CET)
When the antioxidants in our immune system cannot neutralize or convert Reactive oxygen species into safe molecules at the rate at which it is produced then this imbalance is termed as “oxidative stress”. It is related with a wide array of diseases that includes cancer, diabetes, cardiovascular diseases, hypertension etc. These ROS species however are utmost essential for the proper functioning of human body which are produced as a consequence of partial oxidation of cellular metabolism performing essential functions such as protein phosphorylation, activation of several transcriptional factors, apoptosis, immunity, and differentiation. The sources by which these are produced can be broadly classified are intrinsic and extrinsic sources. There are variety of natural antioxidant enzymes of human body that combat against this oxidative stress. The extrinsic sources of ROS include the use of natural plants, extracted flavonoids and vitamins. In this review we will briefly explain how the sources of ROS, its essential function in human body, its elevation and associated damage to organs and effect on various diseases, and a hope of finding a way of how this oxidative stress can be exploited for therapeutic potential.
ARTICLE | doi:10.20944/preprints202012.0082.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Oxidative stress; CYP2E1; Ischemia/reperfusion; Inflammation; Blood-brain barrier
Online: 3 December 2020 (11:05:57 CET)
Despite existing strong evidence on oxidative markers overproduction following ischemia/reperfusion (I/R), the mechanism by which oxidative enzyme Cytochrome P450-2E1 (CYP2E1) contributes to I/R outcomes is not clear. In this study, we sought to evaluate the functional significance of CYP2E1 in I/R. CYP2E1 KO mice and controls were subjected to middle cerebral artery occlusion (MCAo-90min) followed by 24hr of reperfusion to induce focal I/R injury models. Then, histological and chemical analyses were conducted to investigate the role of CYP2E1 in lesion volume, oxidative stress, and inflammation exacerbation. Also, the role of CYP2E1 on the BBB integrity was investigated by measuring 20-Hydroxyecosatetraenoic acid (20-HETE) activity, as well as, in vivo BBB transfer rate. Following I/R, the CYP2E1 KO mice exhibited a significantly lower lesion volume, and neurological deficits compared to controls (p<0.005). Also, ROS production, apoptosis, and the neurodegeneration were significantly lower in the CYP2E1(-/-) I/R group (p<0.001). The BBB damage was significantly lower in CYP2E1(-/-) mice compared to WT (p<0.001), while 20-HETE production was increased by 41%. Besides, inflammatory cytokines expression and the number of activated microglia were significantly lower in CYP2E1(-/-) mice following I/R. CYP2E1 suppression ameliorates I/R injury and protects BBB integrity by reducing both oxidative stress and inflammation.
REVIEW | doi:10.20944/preprints202011.0357.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Heart failure; dysfunctional cardiomiocytes; pathophysiological mechanisms; oxidative stress; nutraceuticals
Online: 12 November 2020 (17:25:06 CET)
Heart failure (HF) is a disease state which has been shown to affect 1-2% of the global population, being often associated with comorbidities such as diabetes, hypertension, obesity or hyperlipidaemia which increase the prevalence of the disease, the rate of hospitalization and the mortality. Although recent advances in both pharmacological and non pharmacological approaches have led to significant improvements in clinical outcomes in patients affected by HF, residual unmet needs remain. Treatment of the disease remains unclear particularly related to poorly defined strategies in the early stages of myocardial dysfunction. Nutritional support in patients developing HF and nutraceutical supplementation have recently been shown to may contribute in the protection of the failing myocardium, though their place in the treatment of HF still needs to be better clarified. In this context, the ONUS-HF working group aimed to assess the optimal nutraceutical approach to HF in the early phases of the disease in order to counteract selected pathways which are imbalanced in the failing myocardium. In particular, we reviewed several of the most relevant pathophysiological and molecular changes occurring druing the early stages of myocardial dysfunction. These include mitochondrial and sarcoplasmic reticulum stress, insufficient nitric oxide (NO) release, cardiac stem cell mobilization and imbalanced regulation of metalloproteinases. Several candidates for nutraceutical supplementation in HF, such as CoQ10, grape seed extract, Olea Europea L- related antioxidants, SGLT2 inhibitors-rich apple extract and bergamot polyphenolic fraction have been assessed for their potential contribution to cardiomyocyte prottection. This approach should define the optimal approach for more targeted and successful strategies based on the use of nutraceuticals in HF to be confirmed by means of clinical trials exploring efficacy and safety of these compounds.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Oxidative Stress, ERBBs; OGG1; Base Excision Repair; crosstalk; Thyroid
Online: 27 October 2020 (20:15:19 CET)
Abstract Thyroid diseases have a complex and multifactorial aetiology. Despite the numerous studies on the signals referable to the malignant transition, still remain elusive the molecular mechanisms concerning the role of oxidative stress. Based on its strong oxidative power, H2O2 could be responsible for the high level of oxidative DNA damage observed in cancerous thyroid tissue and hyper-activation of mitogen-activated protein kinase (MAPK), and PI3K/Akt, that mediate ErbB signaling. Increased levels of 8-oxoG DNA adducts have been detected in the early stages of thyroid cancer. These DNA lesions are efficiently recognized and removed by the base excision repair (BER) pathway initiated by 8-oxoG glycosylase1 (OGG1). This study investigated the relationship between the EGFR and OGG1-BER pathways and their mutual regulation following oxidative stress stimulus by H2O2 in human thyrocytes. We clarified the modulation of ErbB receptors and their downstream pathways (PI3K / Akt and MAPK / ERK) under oxidative stress (from H2O2) at the level of gene and protein expression, according to the mechanism defined in a non-pathological cell system, Nthy-ori 3-1. Later, on the basis of the obtained results of gene expression cluster analysis in normal cells, we assessed the dysregulation of the relationships in a model of papillary thyroid cancer with RET/TPC rearrangement (TPC-1). Our observations demonstrated that a H2O2 stress may induce a physiological cross-regulation between ErbB and OGG1-BER pathways in normal thyroid cells (while this is dysregulated in the TPC-1 cells. Gene expression data also delineated that MUTYH gene could play a physiological role in cross-talk between ErbB and BER pathways and this function is instead lost in cancer cells. Overall our data about OGG1 protein expression suggest that the alternative splicing mechanisms may lead to different protein isoforms, physiologically regulated in response to ErbB modulation, and that these could be dysregulated in the progression of thyroid malignancies with RET/TPC rearrangement.
ARTICLE | doi:10.20944/preprints202010.0283.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: psychiatry; major depression; mood disorders; schizophrenia; antioxidants; oxidative stress
Online: 13 October 2020 (14:07:26 CEST)
Psychiatry remains in a permanent state of crisis, which fragmented psychiatry from the field of medicine. The crisis in psychiatry is evidenced by the many different competing approaches to psychiatric illness including psychodynamic, biological, molecular, pan-omics, precision, cognitive and phenomenological psychiatry, folk psychology, mind-brain dualism, descriptive psychopathology, and postpsychiatry. The current “gold standard” DSM/ICD taxonomies of mood disorders and schizophrenia are unreliable and preclude to employ a deductive reasoning approach. Therefore, it is not surprising that mood disorders and schizophrenia research was unable to revise the conventional classifications and did not provide more adequate therapeutic approaches. The aim of this paper is to explain the new nomothetic network psychiatry (NNP) approach, which uses machine learning methods to build data-driven causal models of mental illness by ensembling risk-resilience, adverse outcome pathways (AOP), cognitome, brainome, symptomatome, and phenomenome latent scores in a causal model. The latter may be trained, tested and validated with Partial Least Squares (PLS) analysis. This approach not only allows to compute pathway-phenotypes or biosignatures, but also to construct reliable and replicable nomothetic networks, which are, therefore, generalizable as disease models. After integrating the validated feature vectors into a well-fitting nomothetic network, clustering analysis may be applied on the latent variable scores of the R/R, AOP, cognitome, brainome, and phenome latent vectors. This pattern recognition method may expose new (transdiagnostic) classes of patients which if cross-validated in independent samples may constitute new (transdiagnostic) nosological categories.
ARTICLE | doi:10.20944/preprints202009.0319.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Corynebacterium glutamicum; Oxidative stress; Mycothiol; Mrx1-roGFP2; Redox potential
Online: 14 September 2020 (00:58:07 CEST)
In aerobic environments, bacteria are exposed to reactive oxygen species (ROS). To avoid an excess of ROS, microorganisms are equipped with powerful enzymatic and non-enzymatic antioxidants. Corynebacterium glutamicum, a widely used industrial platform organism, uses mycothiol (MSH) as major low molecular weight (LMW) thiol and non-enzymatic antioxidant. In aerobic bioreactor cultivations C. glutamicum becomes exposed to oxygen concentrations surpassing the air saturation, which are supposed to constitute a challenge for the intracellular MSH redox balance. In this study, the role of MSH was investigated at different oxygen levels (pO2) in bioreactor cultivations in C. glutamicum. Despite the presence of other highly efficient antioxidant systems, such as catalase, the MSH deficient ΔmshC mutant was impaired in growth in bioreactor experiments performed at pO2 values of 30%. At a pO2 level of 20% this growth defect was abolished, indicating a high susceptibility of the MSH-deficient mutant towards elevated oxygen concentrations. Bioreactor experiments with C. glutamicum expressing the Mrx1-roGFP2 redox biosensor revealed a strong oxidative shift in the MSH redox potential (EMSH) at pO2 values above 20%. This indicates, that the LMW thiol MSH is an essential antioxidant to maintain the robustness and industrial performance of C. glutamicum during aerobic fermentation processes.
ARTICLE | doi:10.20944/preprints202008.0389.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: ECN; neuropathic pain; oxidative stress; apoptosis; myelin sheath; spectroscopy
Online: 18 August 2020 (12:00:15 CEST)
7β-(3-ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a sesquiterpenoid obtained from a natural origin (Tussilago farfara)has proved to be effective in minimizing various side effects associated with opioids and nonsteroidal anti-inflammatory drugs. The current study focused on investigating the effects of ECN on neuropathic pain induced by partial sciatic nerve ligation (PSNL) by mainly focusing on oxidative stress, inflammatory and apoptotic proteins expression in mice. Neuropathic pain was induced in mice by PSNL surgery performed on day 1 and ECN (1 and 10 mg/kg, i.p.), was administered once daily for 11 days, starting from the third day after surgery. ECN post-treatment was found to reduce hyperalgesia and allodynia in a dose dependent manner. ECN significantly reversed the severity of neuropathic pain by improving distress symptoms and survival rate. ECN remarkably reversed the histopathological abnormalities associated with oxidative stress, apoptosis and inflammation. Furthermore, ECN prevented the suppression of antioxidants (glutathione, glutathione-S-transferase, catalase, superoxide dismutase, NF-E2-related factor-2 (Nrf2), hemeoxygenase-1 and NAD(P)H: quinone oxidoreductase) by PSNL. Moreover, pro-inflammatory cytokines (tumor necrotic factor alpha, interleukin 1 beta, interleukin 6, cyclooxygenase-2 and inducible nitric oxide synthase) expression was reduced by ECN administration. Treatment with ECN was successful in reducing caspase-3 level consistent with the observed modulation of pro-apoptotic proteins. Additionally, ECN showed protective effect on the lipid content of myelin sheath as evident from FTIR spectroscopy which showed the shift of lipid component bands to higher values. Thus, anti-neuropathic potential of ECN might be due to inhibition of oxidative stress, inflammatory mediators and pro-apoptotic proteins.
ARTICLE | doi:10.20944/preprints202008.0130.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: antioxidant; C2C12 cell; Jakyakgamcho-tang; muscle atrophy; oxidative stress
Online: 5 August 2020 (10:43:24 CEST)
Oxidative stress is a major contributor to muscle aging and loss of muscle tissue. Jakyakgamcho-tang has been used in traditional Eastern medicine to treat muscle pain. Here, we compared various solvent-based Jakyakgamcho-tang extracts in terms of their effects against hydrogen peroxide-induced oxidative stress in murine C2C12 skeletal muscle cells. Total phenolic content and total flavonoid content in 30% ethanol extracts of Jakyakgamcho-tang were higher than those of water extracts of Jakyakgamcho-tang. Ethanol extracts of Jakyakgamcho-tang had stronger antioxidant and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid and 2,2´-diphenyl-1-picrylhydrazyl-scavenging activity than water extracts of Jakyakgamcho-tang. The ethanol extract of Jakyakgamcho-tang inhibited peroxide-induced cell viability and intracellular reactive oxygen species generation more effectively than the water extract of Jakyakgamcho-tang in a dose-dependent manner. These results suggest that the ethanol extract of Jakyakgamcho-tang is relatively more efficacious at protecting against oxidative stress-induced muscle cell death because it prevents reactive oxygen species generation in C2C12 cells. Moreover, the current study indicated that the effective dose of the ethanol extract of Jakyakgamcho-tang required to alleviate muscle pain might be lower than that required for Jakyakgamcho-tang.
REVIEW | doi:10.20944/preprints202008.0119.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: astaxanthin; cardiovascular disease; atherosclerosis; inflammation; oxidative stress; carotenoids; antioxidant
Online: 5 August 2020 (09:53:14 CEST)
Cardiovascular disease is the most common cause of death. Oxidative stress and inflammation are pathophysiological processes involved in the development of cardiovascular diseases, so anti-inflammatory and antioxidant agents that modulate redox balance have become the targets of research to evaluate their molecular mechanisms and therapeutic properties. Astaxanthin, a carotenoid of the xanthophyll group, has potent antioxidant effects due to its molecular structure and its arrangement in the plasma membrane, factors that favor the neutralization of reactive oxygen and nitrogen species. This carotenoid also stands out for its anti-inflammatory activity, possibly interrelated with its antioxidant effect, as well as for its modulation of lipid and glucose metabolism. Considering the potential positive effects of astaxanthin on cardiovascular health evidenced by preclinical and clinical studies, this paper describes the molecular and cellular mechanisms related to the antioxidant and anti-inflammatory properties of this carotenoid in cardiovascular diseases, especially atherosclerosis.
ARTICLE | doi:10.20944/preprints202006.0283.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: Metabolic Syndrome; Obesity; inflammation; Oxidative Stress; nitrosative stress; biomarkers
Online: 23 June 2020 (11:35:38 CEST)
Purpose: To investigate the alterations in nitro-oxidative stress (OS) and antioxidant status in adolescents with metabolic syndrome (MetS) and whether these alterations occur independently from effects of overweight or obesity.Methods: Blood was collected in 47 adolescents with MetS and 94 adolescents without MetS as assessed with the International Diabetes Federation criteria. The International Obesity Task Force (IOTF) criteria were used to classify the subjects into those with overweight or obesity. We measured nitro-oxidative biomarkers including nitric oxide metabolites (NOx), lipid hydroperoxides (LOOH), and malondialdehyde (MDA), and antioxidant biomarkers, i.e. total radical-trapping antioxidant parameter (TRAP), paraoxonase (PON)-1 activity, thiol (SH-) groups, as well as tumor necrosis factor-α, glucose, insulin, triglycerides, uric acid and high-density lipoprotein cholesterol (HDL-C).Results: Logistic regression analysis showed that increased MDA and NOx and a lowered TRAP/uric acid ratio were associated with MetS. Machine learning including soft independent modeling of class analogy (SIMCA) showed that the top-3 most important features of MetS were increased glucose and MDA and lowered HDL-C. Support vector machine using MDA, glucose, insulin, HDL-C, triglycerides and body mass index as input variables yielded a 10-fold cross-validated accuracy of 89.8% when discriminating MetS from controls. The association between MetS and increased MDA was independent from the effects of overweight-obesity. glucose, insulin, triglycerides and HDL-C.Conclusion: In adolescents, increased MDA formation is a key component of MetS, indicating that increased production of reactive oxygen species with consequent lipid peroxidation and aldehyde formation participate in the development of MetS.
ARTICLE | doi:10.20944/preprints202006.0001.v1
Subject: Medicine And Pharmacology, Hematology Keywords: Copper; transfusion-dependent thalassemia; zinc; oxidative stress; antioxidants; biomarkers
Online: 2 June 2020 (09:21:13 CEST)
Measurements of copper and zinc in transfusion-dependent thalassemia (TDT) show contradictory results.Aim of the study: To examine serum levels of these minerals in TDT in relation to iron overload indices and erythron variables. Methods: This study recruited 60 children with TDT and 30 healthy children aged 3-12 years old.Results: Zinc was significantly higher in TDT children than in control children, whilst copper and the copper to zinc ratio were significantly lowered in TDT. Serum zinc was significantly associated with the number of blood transfusions and iron overload variables (including serum iron and TS%) and negatively with erythron variables (including hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin). Serum copper was significantly and negatively associated with the same iron overload and erythron variables. The copper to zinc ratio was significantly correlated with iron, TS%, ferritin, hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin. Albumin levels were significantly higher in TDT children than in control children. Conclusion: Our results suggest that the increase in zinc in children with TDT may be explained by iron loading anemia and hemolysis and the consequent shedding of high amounts of intracellular zinc into the plasma. Increased albumin levels and treatment with Desferral may further contribute towards higher zinc levels in TDT. We suggest that the elevations in zinc in TDT are a compensatory mechanism protecting against infection, inflammation, and oxidative stress. Previous proposals for prophylactic use of zinc supplements in TDT may not be warranted.
REVIEW | doi:10.20944/preprints202003.0346.v1
Subject: Biology And Life Sciences, Virology Keywords: COVID-19; nCoV 19; oxidative stress; PARP; PARG; TRPM2
Online: 23 March 2020 (07:40:50 CET)
The emerging new Coronaviridae member, nCoV 19, outbreak announced a pandemic by WHO with an increased morbidity and mortality rate worldwide. nCoV 19 known as the third highly pathogen coronavirus in the human population after the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), the nCoV 19. The renin-angiotensin (RAS) signaling pathway, oxidative stress and cell death, cytokines storm and endothelial dysfunction are four major pathways involved in the pathogenesis of nCoV 19. Acute respiratory distress syndrome (ARDS) generally develops with a massive oxidative/nitrosative stress following virus entry and RAS activation. The DNA damage subsequent to oxidative burst activates poly-ADP ribose polymerase-1 (PARP-1), viral macrodomain (NSP3) poly (ADP-ribose) glycohydrolase (PARG) and transient receptor potential channel, melastatin 2 (TRPM2) in a sequential manner ultimately leading to apoptosis and necrosis due to NAD and ATP depletion. Regarding the molecular mechanisms involved in nCoV 19 pathogenesis, angiotensin II receptor blockers and/or PARP, PARG and TRPM2 blockers could be engaged as therapeutic candidates for inhibition of RAS and quenching oxidative stress, respectively. In this review, the molecular aspects of nCoV 19 pathogenesis would be studied precisely and possible therapeutic targets would be proposed. It is recommended to evaluate the proposed drugs and supplements via registered clinical trials along with conventional guideline-based multi-drug regimen.
REVIEW | doi:10.20944/preprints202002.0349.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: carotenoids; seaweeds; antioxidants; astaxanthin; fucoxanthin; anti-obesity; oxidative stress
Online: 24 February 2020 (12:26:44 CET)
Present-day lifestyle associated with high calorie-fat intake and accumulation, as well as energy imbalance, has led to the development of obesity and its comorbidities, which have emerged as some of the major health issues globally. To combat the disease, many studies have reported the anti-obesity effects of natural compounds in foods, with some advantages over chemical treatments. Carotenoids, particularly xanthophyll derived from seaweeds, have attracted the attention of researchers due to their notable biological activities, which are associated mainly with their antioxidant properties. Their involvement in oxidative stress modulation, regulation of major transcription factors and enzymes as well as their antagonistic effects on various obesity parameters have been examined in both in-vitro and in-vivo studies. The present review is a collation of published research over the last decade on the anti-oxidant properties of seaweed xanthophyll carotenoids, with a focus on fucoxanthin and astaxanthin and their mechanisms of action in obesity prevention and treatment.
ARTICLE | doi:10.20944/preprints201911.0358.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: abiotic stress; oxidative stress; salinity; nutrient deficiency; osmolytes; methylglyoxal
Online: 28 November 2019 (09:49:35 CET)
This study was undertaken to elucidate the role of trehalose (Tre) in mitigating oxidative stress under salinity and low P in maize. Eight-day-old maize seedlings of two maize varieties, BARI Hybrid Maize-7 and BARI Hybrid Maize-9 were subjected to salinity (150 mM NaCl), low P (5 µM KH2PO4) and their combined stress with or without 10 mM Tre for 15-d.Salinity and combined stress significantly inhibited the shoot length, root length, and root volume, whereas, low P increased the root length and volume in both genotypes. Exogenous Tre in the stress treatments increased all of the growth parameters as well as decreased the salinity, low P and combined stress-mediated Na+/K+, ROS, MDA, LOX activity and MG in both genotypes. Under salinity and low P stress, the SOD activity increased in both genotypes, but the activity decreased in combined stress. POD activity increased in all stress treatments. Interestingly, Tre application enhanced the SOD activity in all the stress treatments but inhibited the POD activity. Both CAT and GPX activity were increased by saline and low P stress while the activities inhibited in combined stress. Similar results were found for APX, GR, and DHAR activities in both genotypes. However, MDHAR activity was inhibited in all the stresses. Interestingly, Tre enhanced CAT APX, GPX, GR, MDHAR and DHAR activities suggesting the amelioration of ROS scavenging in maize under all the stresses. Increased GST activity in presence or absence of Tre might involve in detoxification of hydroperoxides as well as leaf senescence. On the other hand, increased glyoxalase activities in saline and low P stress in BHM-9 suggested better MG detoxification system because of down-regulation of Gly-I activity in BHM-7 in those stresses. Tre also increased the glyoxalase activities in both genotypes under all the stresses. Tre improved the growth in maize seedlings by decreasing Na+/K+, ROS, MDA, and MG through regulating antioxidant and glyoxalase systems.
ARTICLE | doi:10.20944/preprints201911.0135.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: cytokines, neuro-immune, inflammation, antioxidants, oxidative stress, paraoxonase 1
Online: 12 November 2019 (17:02:22 CET)
Accumulating evidence suggests that TNF-α-mediated immune-neurotoxicity contributes to cognitive impairments and the overall severity of schizophrenia (OSOS). There are no data whether peripheral IL-6 and IL-4 may affect the phenome of schizophrenia above and beyond the effects of TNF-α and whether those cytokines are regulated by lowered natural IgM to malondialdehyde (MDA) and paraoxonase 1 enzyme activity. We assessed the aforementioned biomarkers in schizophrenia patients with (n=40) and without (n=40) deficit schizophrenia and 40 healthy controls. Deficit schizophrenia was best predicted by a combination of increased IL-6 and PON1 status (QQ genotype and lowered CMPAase activity) and lowered IgM to MDA. Partial Least Squares bootstrapping shows that 41.0% of the variance in negative symptoms, psychosis, hostility, excitation, mannerism, psychomotor retardation, and formal thought disorders was explained by increased TNF-α and PON1 status (QQ genotype and lowered CMPAase activity), lowered IL-4 and IgM to MDA as well as male sex and lowered education. We found that 47.9% of the variance in verbal fluency, word list memory, true recall, Mini-Mental State Examination, and executive functions was predicted by increased TNF-α and lowered IL-4, IgM to MDA and education. In addition, both TNF-α and IL-4 levels were significantly associated with lowered IgM to MDA, while TNF-α was correlated with PON1 status. These data provide evidence that the symptomatic (both the deficit subtype and OSOS) and cognitive impairments in schizophrenia are to a large extent mediated by the effects of immune-mediated neurotoxicity as well as lowered regulation by the innate immune system.
ARTICLE | doi:10.20944/preprints201908.0132.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: schizophrenia; inflammation; oxidative stress; neuro-immune; gut bacteria; antioxidants
Online: 11 August 2019 (14:58:43 CEST)
In schizophrenia, a single latent trait underlies psychosis, hostility, excitation, mannerism, negative (PHEMN) symptoms, formal thought disorders (FTD) and psychomotor retardation (PMR). Schizophrenia is accompanied by a breakdown of gut and blood-brain-barrier (BBB) pathways, increased tryptophan catabolite (TRYCAT) levels, bacterial translocation, and lowered natural IgM and paraoxonase (PON)1 activity. The aim of this study was to examine the factor structure of schizophrenia symptom domains and the biomarker correlates of these factors. We recruited 80 patients with schizophrenia and 40 healthy subjects and assessed the IgA/IgM responses to paracellular/transcellular (PARA/TRANS) ratios, IgA responses to TRYCATs, natural IgM to malondialdehyde and Gram-negative bacteria, and PON1 enzymatic activity.Direct Hierarchical Exploratory Factor Analysis showed a bifactorial oblique model with a) a general factor which loaded highly on all symptom domains, named overall severity of schizophrenia (“OSOS”); and b) a single-group factor (SGF) loading on negative symptoms and PMR. We found that 40% of the variance in the OSOS score was explained by IgA/IgM to PARA/TRANS ratio, male sex and education while 36.9% of the variance in SGF score was explained by IgA to PARA/TRANS, IgM to Gram-negative bacteria, female sex (positively associated) and IgM to MDA, and PON1 activity (negatively associated). Schizophrenia phenomenology comprises two biologically-validated dimensions, namely a general OSOS dimension and a single-group negative symptom dimension, which are associated with a breakdown of gut/BBB barriers, increased bacterial translocation and lowered protection against oxidation, inflammation and bacterial infections through lowered PON1 and natural IgM.
ARTICLE | doi:10.20944/preprints201902.0182.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: schizophrenia; inflammation; neuro-immune; oxidative stress; TRYCATs; leaky gut
Online: 19 February 2019 (12:14:29 CET)
Deficit schizophrenia is characterized by leaky tight and adherens junctions and bacterial translocation. Here we examine whether (deficit) schizophrenia is accompanied by leaky paracellular, transcellular and vascular barriers in the gut and blood brain barriers. We measured IgA responses to occludin, claudin-5, E-cadherin and β-catenin (paracellular pathway, PARA), talin, actin, vinculin and epithelial intermediate filament (transcellular pathway, TRANS) and plasmalemma vesicle-associated protein (PLVAP, vascular pathway) in 78 schizophrenia patients and 40 controls. IgA responses to claudin-5, E-cadherin and β-catenin, the sum of the four PARA proteins and the ratio PARA/TRANS were significantly higher in deficit schizophrenia than in non-deficit schizophrenia and controls. A large part of the variance in PHEMN (psychosis, hostility, excitation, mannerism and negative) symptoms, psychomotor retardation, formal thought disorders, verbal fluency, word list memory, word list recall and executive functions was explained by the PARA/TRANS ratio coupled with plasma IgA responses to Gram-negative bacteria, IgM to malondialdehyde, CCL-11 (eotaxin), IgA levels of the ratio of noxious to more protective tryptophan catabolites (NOX/PRO TRYCATs) and a plasma immune activation index. Moreover, IgA levels to Gram-negative bacteria were significantly associated with IgA to E-cadherin, β-catenin and PLVAP, while IgA levels to claudin-5 were significantly predicted by IgA to E-cadherin, NOX/PRO TRYCAT ratio, Gram-negative bacteria and CCL11. The phenomenology of the deficit syndrome is to a large extent explained by the cumulative effects of lowered natural IgM, breakdown of the paracellular and vascular pathways, increased bacterial translocation, peripheral immune-inflammatory responses and indices of BBB breakdown.
ARTICLE | doi:10.20944/preprints201901.0108.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: schizophrenia, inflammation, nitrosative stress, tryptophan catabolites, cytokines, oxidative stress
Online: 11 January 2019 (10:37:50 CET)
BACKGROUND: Stable-phase schizophrenia may comprise two distinct nosological entities namely Major Neuro-Cognitive Psychosis (MNP, largely overlapping with the deficit syndrome) and simple NP (SNP), which are defined by neuroimmune and neurocognitive abnormalities. Furthermore, cognitive impairments and PHEM (psychotic, hostility, excitation, mannerism) and negative symptoms load on the same dimension.METHODS: The current study aimed to investigate associations of psychomotor retardation (PMR) and clinical as well as biomarker characteristics of schizophrenia. We recruited 40 healthy controls and 79 schizophrenia patients and measured IgA responses to tryptophan catabolites (TRYCATs), IgM to malondialdehyde and nitroso (NO)-cysteinyl, macrophage inflammatory protein-1 (MIP-1), soluble interleukin (IL)-1 receptor antagonist (sIL-1RA), IL-10, CCL-11 as well as PMR items of different rating scales and motor screening task (MOT). RESULTS: PMR differentiated schizophrenia from controls and MNP from SNP. In addition, PMR was strongly associated with executive functions, deficits in episodic and semantic memory, PHEM and negative (PHEMN) symptoms. Around 50% of the variance in PMR was predicted by the cumulative effects of immune activation, CCL-11, TRYCATs and NO-Cysteinyl levels, and lowered natural IgM. PRM may be reliably combined with PHEMN symptoms and memory and executive impairments into one latent vector reflecting overall psychopathology.CONCLUSIONS: Current findings indicate that PMR may be a key psychopathological feature of schizophrenia and mainly MNP. In addition, PMR and associated impairments in memory and executive functions, and PHEMN symptoms may be driven by deficits in the compensatory immune regulatory system (natural IgM) combined with increased production of neurotoxic immune products, namely TRYCATs and IgM to NO-cysteinyl, and an endogenous cognition deteriorating chemokine, namely CCL-11.
ARTICLE | doi:10.20944/preprints201810.0563.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mitochondrial metabolism; aging; monoacylglyceride; polyunsaturated fatty acids; oxidative stress
Online: 24 October 2018 (09:40:31 CEST)
During the last decade, essential polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) derived from marine sources have been investigated as nonpharmacological dietary supplements to improve different pathological conditions, as well as aging. The aim of this study was to determine the effects of dietary n-3 PUFA monoacylglycerides (MAG, both EPA and DHA) on the mitochondrial metabolism and oxidative stress of a short-lifespan model, Drosophila melanogaster, sampled at five different ages. Our results showed that diets supplemented with MAG-EPA and MAG-DHA increased median lifespan by 14.6% and decreased mitochondrial proton leak resulting in an increase of mitochondrial coupling. The flies fed on MAG-EPA also had higher electron transport system capacity and mitochondrial oxidative capacities. Moreover, both n-3 PUFAs delayed the occurrence of lipid peroxidation, but only flies fed the MAG-EPA diet showed maintenance of superoxide dismutase activity during aging. Our study therefore highlights the potential of n-3 PUFA monoacylglycerides as nutraceutical compounds to delay the onset of senescence by acting directly or indirectly on the mitochondrial metabolism, and suggests that Drosophila could be a relevant model for the study of the fundamental mechanisms linking the effects of n-3 PUFAs to aging.
ARTICLE | doi:10.20944/preprints201807.0219.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: High-Fat Diet, Dietary Supplement, Oxidative stress, Inflammation, Neurodegeneration.
Online: 12 July 2018 (15:45:18 CEST)
Obesity and metabolic disorders can be risk factors for the onset and development of neurodegenerative diseases. The aim of the present study was to investigate the protective effects on dysmetabolism and neurodegeneration of a natural dietary supplement (NDS), containing Curcuma longa, silymarin, guggul, chlorogenic acid and inulin, on the brains of high fat diet (HFD)-fed mice. A decreased expression of FACL-4, CerS-1 and CerS-4, reduced cholesterol concentration, increased IR expression and insulin signaling activation, were found in brains of NDS-treated HFD mice, suggesting that NDS is able to prevent brain lipid accumulation and central insulin resistance. In the brains of NDS-treated HFD mice, the levels of RNS, ROS and lipid peroxidation, the expression of p-ERK, H-Oxy, i-NOS, HSP60, NF-kB, GFAP, IL-1β, IL-6, and CD4 positive cell infiltration were lower than in untreated HFD mice, suggesting antioxidant and anti-inflammatory effects of NDS. The decreased expression of p-ERK and GFAP in NDS-treated HFD mice was confirmed by immunofluorescence. Lastly, a lower number of apoptotic nuclei was found in cortical sections of NDS-treated HFD. All these data indicate that NDS exerts neuroprotective effects in HFD mice by reducing brain fat accumulation, oxidative stress and inflammation and improving brain insulin resistance.
REVIEW | doi:10.20944/preprints201802.0104.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: myeloperoxidase, leukocytes, inflammation, oxidative stress, chronic diseases, disease biomarker
Online: 15 February 2018 (16:54:25 CET)
Myeloperoxidase (MPO) belong to the family of heme containing peroxidases, produced mostly from polymorphonuclear neutrophils. The active enzyme (150 kD) is the product of MPO gene located on long arm of chromosome 17. The primary gene product undergoes several modifications like removal of introns and signal peptide and leads to the formation of enzymatically inactive glycosylated apoproMPO which complexes with chaperons, producing active proMPO by the insertion of heme moiety. The active enzyme is a homodimer of heavy and light chain protomers. This enzyme is released into extracellular fluid after oxidative stress and different inflammatory responses. MPO is the only type of peroxidase using H2O2 to oxidize several halides and pseudohalides to form different hypohalous acids. So the antibacterial activities of MPO involve the production of reactive oxygen and reactive nitrogen species. Controlled MPO release at the site of infection is of prime importance for its efficient activities. Any uncontrolled degranulation exaggerates the inflammation that can also lead to tissue damage even in absence of inflammation. Several types of tissue injuries and pathogenesis of several other major chronic diseases like rheumatoid arthritis, cardiovascular diseases, liver diseases, diabetes and cancer have been reported to be linked with myeloperoxidase derived oxidants. So the enhanced level of MPO activity is one of the best diagnostic tool of inflammatory and oxidative stress biomarkers among these commonly occurring diseases.
ARTICLE | doi:10.20944/preprints202209.0360.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Breast cancer; Oxidative stress; Healthy lifestyle; Catalase; Gene–environment interaction
Online: 23 September 2022 (07:11:45 CEST)
Lifestyle has been associated with breast cancer risk through different pathways, including oxidative stress. Antioxidant enzymes are endogenous defense mechanisms against oxidative stress damage, and this response might be modulated by the genetic variation in these enzyme-codifying genes. This study aimed to analyze the synergistic effect of an antioxidant Healthy Lifestyle Index (HeLiX) composed of principal components of Western dietary pattern, alcohol consumption, smoking and physical activity, and genetic polymorphisms in the first-line antioxidant response family genes SOD, GPX, and CAT on breast cancer risk. We included 176 SNPs, and only CAT rs554576 remained significant after correction for multiple comparisons. Breast cancer odds were reduced at the highest (T3) and medium (T2) tertiles of the HeLiX. When stratified by HeLiX, we observed a reduced risk of breast cancer with at least one T-allele, and the effect increased in a dose-dependent manner. Compared to the reference category (HeLiX T1 and AA genotype), women at the HeLiX T3 with AT and TT genotypes in postmenopausal women showed an OR = 0.15 (95% CI 0.07–0.32). For HeLiX T2 and AT genotype OR = 0.26 (95% CI 0.13–0.54); for TT genotype OR = 0.24 (95% CI 0.12–0.45). For premenopausal women, at the HeLiX T3 and AT genotype OR = 0.29 (95% CI 0.13–0.62); for the TT genotype OR = 0.21 (95% CI 0.08–0.51). We also observed an inverse association for HeLiX T2 and TT genotype (OR 0.39 95% CI 0.17–0.87). Our study shows a significant synergistic gene-environment interaction on an additive scale, contributing to understanding pathways involved in breast cancer etiology and prevention.
REVIEW | doi:10.20944/preprints202209.0354.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Wound healing; metastasis; oxidative stress; macrophage; HIF; NF-kB; Nrf2
Online: 23 September 2022 (03:28:28 CEST)
Many signaling pathways, molecular and cellular actors which are critical for wound healing have been implicated in cancer metastasis. These two conditions are a complex succession of cellular biological events and accurate regulation of these events is essential. Apart from inflammation, macrophages-released ROS arise as major regulators of these processes. But, whatever the pathology concerned, oxidative stress is a complicated phenomenon to control and requires a finely tuned balance over the different stages and responding cells. This review provides an overview of the pivotal role of oxidative stress in both wound healing and metastasis, encompassing the contribution of macrophages. Indeed, macrophages are major ROS producers but also appear as their targets since ROS interfere with their differentiation and function. Elucidating ROS functions in wound healing and metastatic spread may allow the development of innovative therapeutic strategies involving redox modulators.