REVIEW | doi:10.20944/preprints202302.0006.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: hormesis; polyphenols; clinical trials; antioxidants; reactive oxygen species; oxidative stress; plant-derived antioxidants; dietary antioxidants; nutritional hormesis; free radicals
Online: 1 February 2023 (03:03:40 CET)
A consistent factor in the epidemic of chronic disease is a pro-inflammatory metabolic state. The ability of clinicians to use nutrients to balance inflammation by supporting oxidant homeostasis rests on the quality of research within the field of antioxidants. Understanding the intersection of two prominent theories regarding the role of antioxidants in quelling inflammation, nutritional hormesis and oxidant scavenging, will enable the therapeutic use of antioxidants in clinical practice. This review investigates the less well-established theory, nutritional hormesis, which has not been comprehensively reviewed recently to our knowledge. To understand the state of research on the hormetic response, we conducted a comprehensive literature review describing the relationship between dietary antioxidants, hormesis, and chronic disease. We used an adaptive search strategy in PubMed and Scopus, retrieving a total of 343 articles, of which 218 were unique. Title and abstract screenings were conducted by two reviewers independently with a third as a tiebreaker, resulting in 152 articles included in this review. Most studies reviewed the hormetic response in plant and cell models (73.6%) while only 2.2% were conducted in humans. Limitations exist in translating plant/cell/animal models into the complexities of human biochemistry and physiology that warrant consideration before extrapolating such results into clinical practice. A critical hurdle in our literature review process is the lack of standardized nomenclature describing the hormetic effect in the research community that challenges the ability to comprehensively review the subject matter. Further, aA knowledge gap exists between the cell culture and animal model research that shows a biphasic, hormetic quality to the role of antioxidants and the observational human studies, which have yet to corroborate these findings. Therefore, we cannot accurately translate this research into clinical care at this time.
REVIEW | doi:10.20944/preprints202109.0136.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: onion; polyphenolics; antioxidants; extraction; health
Online: 8 September 2021 (08:48:16 CEST)
Onions are an excellent source of a variety of essential antioxidants, polyphenols, and other phytonutrients. These onions were used to enhance the meal's flavour and aroma. Additionally, onions have long been recognised for their ability to change food texture, making it more pleasant for eating. Among the most significant phenolic compounds identified in onions was Quercetin, which has been proven to be very helpful for maintaining good health by reducing the risk of heart disease, cancer, and a number of other severe conditions. Polyphenol extraction is essential for the effective usage and research of these phytochemicals. Previously, the extraction process was complicated by a variety of traditional methods, but with the aid of contemporary technology, the procedure was simplified. Additionally, it was found that red onions had greater health benefits than yellow onions, which were the most commonly used kind at the time. Apart from their health benefits, polyphenols were well recognised for their industrial use in dyeing, polymer manufacturing, and resin synthesis.
ARTICLE | doi:10.20944/preprints202209.0064.v2
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Antarctica; antioxidants; cadmium; copper; fish; metallothioneins
Online: 6 October 2022 (09:57:16 CEST)
Metal bioaccumulation and metallothionein (MT) expression were investigated in gills and liver of the red-blooded Antarctic teleost Trematomus hansoni with the aim to evaluate the possibility for this species to face, with adequate physiological responses, an increase of copper or cadmium concentrations in the environment. Specimens of this Antarctic fish were collected from Terra Nova Bay (Ross Sea) and used for a metal exposure experiment in controlled laboratory condi-tions. The two treatments lead to a significant accumulation of both metals and an increase of gene transcription only for the MT-1. The biosynthesis of MTs was verified especially in speci-mens exposed to Cd, but the majority of these proteins were soon oxidized, probably because they were involved in cell protection against the risk of oxidative stress, by reactive oxygen spe-cies scavenging. The obtained data highlighted the phenotypic plasticity of T. hansoni, a species evolved in an environment characterized by natural high concentrations of Cu and Cd, and maybe the possibility for the Antarctic fish to face the challenges of a world that is becoming every day more toxic.
ARTICLE | doi:10.20944/preprints202206.0085.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: Ranolozine; Insuline; astrocytes; inflammation; antioxidants
Online: 6 June 2022 (10:14:05 CEST)
Ranolazine (Rn) is a drug used to treat persistent chronic coronary ischemia. It has also been shown to have therapeutic benefits on the central nervous system and an anti-diabetic effect by lowering blood glucose levels and however, no effects of Rn on cellular sensitivity to insulin (Ins) have been demonstrated yet. The present study aimed to investigate the permissive effects of Rn on the actions of Ins in astrocytes in primary culture. Ins at 10-8 M, Rn (10-6 M) and Ins+Rn (10-8 M and 10−6 M respectively) were added to astrocytes during 24 h. In comparison to control cells, Rn and/or Ins caused modifications in cell viability and proliferation. p-AKT, p-ERK, p-eNOS, Mn-SOD, COX-2, and the anti-inflammatory protein COX-2 were all upregulated by ins. On the contrary, no significant changes were found in the protein expression of Cu/Zn-SOD, NF-κB and IκB. The presence of Rn produced an increase in p-ERK protein and a significant decrease in COX-2 protein expression. Furthermore, Rn significantly increased the effects of Ins on the expression of p-AKT, p-eNOS, p-ERK, Mn-SOD, and PPAR-γ. On the other hand, Rn+Ins produced a significant decrease in COX-2 expression. In conclusion, Rn facilitated the effects of insulin on the p-AKT, p-eNOS, p-ERK, Mn-SOD and PPAR-γ, signaling pathways, as well as on the anti-inflammatory and antioxidant effects of the hormone.
ARTICLE | doi:10.20944/preprints202304.0497.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Antioxidants; Flavonoids; Moringa; Provitamin A; Total Phenolics
Online: 18 April 2023 (05:49:04 CEST)
This study aimed to assess the variations in the nutritional attributes of thirteen Moringa oleifera cultivars. Leaves from six-month-old plants were harvested and tested for various nutritional attributes. There were significant (p ≤ 0.05) differences in the carbohydrates, energy, some of the sugars and fibre amongst the cultivars. The levels of moisture in the cultivars ranged from 7.10% to 8.20%. Additionally, there were significant (p ≤ 0.05) differences across the cultivars in microelements studied except for zinc (Zn). These data revealed that plants from different geographical provenances differed in their adapting to varied environments. In general, under the same cultivation, management and environmental conditions, the main reasons for these differences occurred in cultivars could be associated with the genetic background of each M. oleifera germplasm. However, the study cautions on the differences of nutritional properties, as some of the cultivars have been reported not to be pharmacological potent.
REVIEW | doi:10.20944/preprints202103.0432.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: antioxidants; compounds; garlic; onion; pharmacological
Online: 17 March 2021 (09:02:03 CET)
Garlic and onion are either cooked like a vegetable because of their green leaves or are also used as a condiment. Many scientific studies affirm the positives of both for their anti-inflammatory, antioxidant, and antimicrobial potential. Moreover, garlic and onion are regularly employed to treat cardiovascular illnesses, strokes, atherosclerosis, hypertension, hyperlipidemias, and thrombosis, and are also proved effective against Alzheimer's, diabetes, and cancers. Here we have compiled a piece of information regarding the compounds present in garlic and onion along with their pharmacological properties. Although much more studies are required to refine the utilization and enhance garlic and medicine's effectiveness. We hope this work will provide helpful information regarding their pharmacological aspects.
ARTICLE | doi:10.20944/preprints202007.0146.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: fenugreek; aging; liver; antioxidants; mice
Online: 8 July 2020 (11:03:10 CEST)
Fenugreek seeds are widely used in Asia and other places of the world for their nutritive and medicinal properties. In Asia, Fenugreek seeds are also widely recommended for the geriatric populations. Here, we evaluated for the first time the effect of fenugreek seed feed supplementation on the liver antioxidant defense systems in aging mice. The study was conducted on 12 months aged mice which were given fenugreek seed dietary supplement. We have evaluated the activities of various antioxidant defense enzymes like superoxide dismutase (SOD), glutathione reductase (GR), and glutathione peroxidase (GPx), and estimated the phenolics and free radical scavenging properties in mice liver upon fenugreek supplementation. The estimation of SOD, GPx and GR activities in aged mice liver revealed a significant (P<0.01) difference among all the liver enzymes. Overall, this study reveals that fenugreek seed dietary supplementation has a positive effect in on the activities of the hepatic antioxidant defense enzymes in the aged mice.
ARTICLE | doi:10.20944/preprints202206.0208.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Disease; fibroid; micronutrients; inflammation; antioxidants; cytokines; diets
Online: 15 June 2022 (02:24:41 CEST)
Uterine fibroid (UF) is a tumour in some parts of the uterus, which introduces health challenges or death due to failed surgery among women globally. This study was designed to ascertain the involvement of micro-nutrients, inflammation, and antioxidant enzymes in the UF development to gain further insights and provide a strategy for managing the disease. One hundred ninety reproductive-aged women were recruited and classified equally into case and control subjects. The supernatant obtained from excised tissues from the fibroid and the normal samples from the adjacent myometrium were assessed for the selected biochemical parameters with standard methods. The levels of vitamin A and sodium between 26-35 years; vitamins D, E, zinc, and selenium between 46-55 years; and vitamin E at 56 years and above significantly decreased (p<0.05). Interleukin-2 (IL-2) level significantly increased (P < 0.05) among the case between 36-45 years. An increase in the activity of glutathione-s-transferase and the reduction in glutathione peroxidase activity and vitamin A level in the uterus between 26-45 years were the most pronounced significant findings (p<0.05) recorded. Prolonged vitamin A deficiency coupled with excess sodium salts facilitating inflammation induced by IL-2 are critical factors for UF development.
REVIEW | doi:10.20944/preprints202102.0573.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Antioxidants; resveratrol; MitoQ; SkQ; neurodegenerative disease
Online: 25 February 2021 (10:22:18 CET)
Growing evidence from neurodegenerative disease research supports an early pathogenic role for mitochondrial dysfunction in affected neurons that precedes morphological and functional deficits. Resulting oxidative stress and respiratory malfunction contribute to neuronal toxicity and may enhance the vulnerability of neurons to continued assault by aggregation-prone proteins. Consequently, targeting mitochondria with antioxidant therapy may be a non-invasive, inexpensive, and viable means of strengthening neuronal health and slowing disease progression, thereby extending quality of life. We review the pre-clinical and clinical findings available to date of the natural bioactive phenol resveratrol and two synthetic mitochondrial-targeted antioxidants MitoQ and SkQ.
ARTICLE | doi:10.20944/preprints201807.0039.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: xanthohumol; biotinylated chalcones; anticancer activity; antioxidants
Online: 3 July 2018 (11:42:41 CEST)
Two biotinylated derivatives of the main hop chalcone xanthohumol (1) were prepared by a one-step synthesis via esterification using biotin and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC HCl) and 4-dimethylaminopyridine (DMAP) as coupling reagents. The products were characterized spectroscopically and their antiproliferative activity toward MCF-7, MCF-10A, HepG2, MDA-MB-231, 4T1 and Balb/3T3 cell lines was investigated using the SRB assay. For all three tested compounds the best activity was noted in the case of human (MCF-7) and mice (4T1) breast cancer cell lines (IC50 values < 9 μM). Both biotinylated derivatives showed higher anticancer activity than xanthohumol (1) towards all types of tested breast cancer cells. Double biotinylated xanthohumol (3) proved to be the most active in inhibiting cell growth, with IC50 values equal to 5.35 ± 1.5 μM for 4T1 and 8.03 ± 0.53 µM for MCF-7 cell lines. Compound 3 was also more active than 1 and 2 against liver cancer cells HepG2 (IC50 = 17.37 ± 5.1 μM), while the IC50 values for 1 and 2 were equal to 21.5 ± 2.7 and 22.1 ± 3.9 µM, respectively. 4‑O‑biotinylxanthohumol (2) was the second most active growth inhibitor, particularly with respect to MCF-7 (IC50 = 6.19 ± 1.7 μM) and 4T1 (IC50 = 6.64 ± 0.4 μM) cell lines. The antioxidant activity was evaluated using the 1.1-diphenyl-2-picrylhydrazyl radical (DPPH) method. All tested compounds (1-3) have antioxidant activity between 2.73 and 3.38 mM. It was reported for the first time that new prenylated chalcones containing the biotin moiety effectively inhibited proliferation of cancer cells in vitro.
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.
COMMUNICATION | doi:10.20944/preprints202109.0205.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Antioxidants; Medicinal plant; Justicia adhatoda L.
Online: 5 January 2022 (10:37:29 CET)
There are many medicinal plants that have various medicinal properties in their different parts. The medicinal plants are major backbone of pharmaceutical industries. In this article we compare the antioxidants properties from various plants parts (root, stem, leaf, flower and bark) of the most important medicinal plant, Justicia adhatoda L. Various plant parts showed the good amount of antioxidant properties. These results enhance the medicinal properties of this plant due to the presence of good amount of antioxidants; among all the plant parts leaves and flowers showed maximum natural antioxidants, hence the study could be saying that this plant has good efficacy of antioxidants.
ARTICLE | doi:10.20944/preprints202209.0298.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: granulocytes; COVID-19; antioxidants; inflammation; eicosanoids; receptors-coupled G protein; SOD
Online: 20 September 2022 (09:24:19 CEST)
Abstract: It is assumed that upon SARS-CoV-2 infection granulocytes can undergo potentially destructive oxidative burst. Therefore, the aim of this study was to evaluate some parameters of redox and inflammatory signaling in granulocytes of recovered and of deceased COVID-19 pa-tients. Granulocytes were isolated from the blood of 32 COVID-19 patients on admission to the hospital (16 survived and 16 died within a week). The levels of proteins (immunoassay), eico-sanoids (UPLC-MS) and antioxidants activity (spectrophotometry) were examined. Enhanced activation of Nrf2 and NFκB and the levels of heme oxygenase and proinflammatory cytokines where found in granulocytes of all COVID-19 patients, while Cu,Zn-SOD and Mn-SOD activities were decreased, especially in deceased patients. Moreover, in patients who died increased levels of pro-inflammatory eicosanoids (PGE2 and TXB2) and decreased of anti-inflammatory (15d-PGJ2 and 5-HETE) were observed. However TXB2 was decreased, and IL-2 and IL-10 levels were in-creased in survivors, if compared both to healthy subjects and deceased patients, who did not change their cytokine generation. Therefore, it seems that by triggering transcription factors granulocytes activate redox signaling, leading to the production of pro-inflammatory eicosanoids, while reducing cellular antioxidant capacity via SOD, they express altered response to COVID-19, which might result in the onset of the vicious cycle of systemic oxidative stress in deceased patients.
ARTICLE | doi:10.20944/preprints202305.2069.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: BPAN; WDR45; antioxidants; autophagy; iron accumulation
Online: 31 May 2023 (03:32:17 CEST)
Neurodegeneration with brain iron accumulation (NBIA) is a group of rare neurogenetic dis-orders frequently associated with iron accumulation in the basal nuclei of the brain. Among NBIA subtypes, β -propeller protein-associated neurodegeneration (BPAN) is associated with mutations in the autophagy gene WDR45. The aim of this study was to demonstrate autophagic defects and secondary pathological con-sequences in cellular models derived from two patient harboring WDR45 mutations. Both protein and mRNA expression levels of WDR45 were decreased in patient-derived fibro-blasts. In addition, the increase of LC3B upon treatments with autophagy inducers or inhibitors was lower in mutant cells compared to control cells, suggesting decreased autophagosome formation and impaired autophagic flux. Transmission electron microscopy (TEM) analysis showed mitochondrial vacuolization associated with accumulation of lipofuscin-like aggregates containing undegraded material. Autophagy dysregulation was also associated with iron ac-cumulation and lipid peroxidation. In addition, mutant fibroblasts showed altered mitochon-drial bioenergetics. Antioxidants such as pantothenate, vitamin E and α-lipoic prevented lipid peroxidation and iron accumulation. However, antioxidants were not able to correct the ex-pression levels of WDR45 neither the autophagy defect nor cell bioenergetics. Our study demonstrated that WDR45 mutations in BPAN cellular models impaired autophagy, iron metabolism and cell bioenergetics. Antioxidant partially improved cell physiopathology, however autophagy and cell bioenergetics remained affected.
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.
REVIEW | doi:10.20944/preprints202305.0028.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: antioxidants; arterial aging; airway inflammation; -Klotho; ROS; hydrogen peroxide; SOD; heart rate variability
Online: 1 May 2023 (11:23:19 CEST)
Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in the disease pathomechanism. Unbalance between oxidants and antioxidant defense mechanisms not only amplifies the local inflammatory processes, but it also worsens cardiovascular health and contribute to the COPD related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced together with some suggestions for further research on the field.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Ultraviolet; superoxide; singlet Oxygen; cell blebbing; skin aging; peroxidative cascade; antioxidants
Online: 21 October 2020 (10:32:55 CEST)
The interaction of ultraviolet radiation with biological matter results in direct damage such as pyrimidine dimers in DNA. It also results in indirect damage provoked by the production of Reactive Oxygen Species (ROS) catalyzed by photo-sensitizers. Photosensitizers can be endogenous (e.g. Tryptophan) or exogenous (e.g. TiO2 and other photo-stable UVA sunscreens). Direct damage triggers an inflammatory response and the oxidative and proteolytic bursts that characterize its onset. The inflammatory reaction multiplies the effects of one single photon. Indirect damage, such as the peroxidative cascade in membrane lipids, can extend to thousands of molecular modifications per absorbed photon. Sunscreens should therefore be formulated in the presence of appropriate anti-oxidants. Superoxide and Singlet Oxygen are the main ROS that need to be tackled: this review describes some of the molecular, biochemical, cellular and clinical consequences of exposure to UV radiation as well as some results associated with scavengers and quenchers of Superoxide and Singlet Oxygen, as well as with inhibitors of singlet Oxygen production.
ARTICLE | doi:10.20944/preprints202208.0125.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: antioxidants; bioactive compounds; nutraceuticals; phenols; pomegranate peels
Online: 5 August 2022 (14:38:21 CEST)
Pomegranate use is increasing worldwide as it is considered a tasteful healthy food. It is mainly used as fruit, juice and jam. The pomegranate peel represents about 40-50% of the total fruit weight and contains numerous and diverse bioactive substances. The aim of this research was to analyse the pomegranate peel composition of Wonderful cultivated in Southern Italy and treated with an innovative physic dry concentration procedure. The aim was to verify how the drying process influenced the bioactive compounds that could be used as nutraceuticals. A comparison with the peel composition of freeze dried Wonderful cultivated in Southern Italy, freeze dried Wonderful cultivated in South Africa and freeze-dried pomegranate Kullu and Himachal cultivated in India has been done. Results evidenced that in pomegranate peels of Wonderful cultivated in Calabria and dried with the innovative process, total phenolic substances, total flavonoids, vitamin C, vitamin E and antioxidant activities, were the highest. Great amounts of single phenolic acids and flavonoids were found in Calabrian Wonderful peels dried with the innovative process. Overall, it emerged that the great amount of bioactive and diverse compounds found in Calabrian Wonderful pomegranate peel, come from the niche pedoclimatic conditions, and the physic drying innovative methodology.
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/preprints202001.0077.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: premenstrual syndrome; depression; anxiety; antioxidants; neuro-immune; inflammation; oxidative stress
Online: 9 January 2020 (08:17:43 CET)
Objective: To examine whether 1) immune and nitro-oxidative stress (IO&NS) biomarkers are associated with premenstrual syndrome (PMS); and 2) changes in IO&NS biomarkers during the menstrual cycle (MC) are associated with PMS symptoms and plasma estradiol and progesterone. Methods: Forty-one women completed the Daily Record of Severity of Problems (DRSP) rating scale during 28 consecutive days and MC Associated Syndrome (MCAS) was diagnosed when the summed DRSP score during the MC is > 0.666 percentile. We assayed plasma levels of complement C3 and C4, highly sensitive C-reactive protein (hsCRP), haptoglobin (Hp), advanced oxidation protein products (AOPP), lipid hydroperoxides (LOOH), nitric oxide metabolites (NOx), total radical-trapping antioxidant parameter (TRAP), sulfhydryl (-SH) groups and the activity of paraoxonase (PON)1 at days 7 (D7), 14 (D14), 21 (D21) and 28 (D28) of the MC. Results: All biomarkers, except hsCRP, showed significant alterations during the MC. Arylesterase (AREase) was lowered at D28, while LOOH increased at D14 and C4 at D21 in women with MCAS. The total DRSP score was predicted by the combined effects of C4 (positively) and AREase and malondialdehyde (MDA) (both inversely associated). Progesterone lowered levels of LOOH, AOPP and C3 and estradiol lowered levels of Hp while both sex hormones increased 4-(chloromethyl)phenyl acetate (CMPA)ase and AREase activities and levels of -SH groups. Conclusion: PMS/MCAS is not accompanied by a peripheral inflammatory response. Lowered MDA and antioxidant defenses and increased C4 may play a role in MC-associated symptoms while sex hormones may have a protective effect against oxidative stress toxicity.
ARTICLE | doi:10.20944/preprints202011.0523.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: deficit schizophrenia; cognition; tryptophan catabolites; neuro-immune; oxidative stress; antioxidants; CCL11
Online: 19 November 2020 (21:06:35 CET)
Recently we showed that schizophrenia and, especially, deficit schizophrenia is accompanied by neurocognitive impairments as measured with different cognitive batteries. The aim of this study was to examine whether a single trait underpins aberrations in 9 key Cambridge Neuropsychological Test Automated Battery (CANTAB) probes, verbal fluency (VFT), world list memory (WLM), true recall, and the Mini Mental State Examination (MMSE). We recruited 80 patients with schizophrenia and 40 healthy controls. All patients were assessed using CANTAB tests, namely paired-association learning (PAL), rapid visual information (RVP), spatial working memory (SWM), one touch stocking (OTS), intra/extradimensional set shifting (IED), and emotional recognition test (ERT). We found that a single latent trait, which is essentially unidimensional, underlies the CANTAB tests, VFT, WLM, True Recall and MMSE. The latent trait shows excellent psychometric properties and fits a reflective model and, therefore, reflects a generalized cognitive decline (GCoDe), which is the cause of aberrations in semantic and episodic memory, recall, executive functions, strategy use, rule acquisition, visual sustained attention, attention set-shifting and emotional recognition. 40.5% of the variance in GCode was explained by CCL11, IgA to tryptophan catabolites, and increased oxidative toxicity. GCoDe explains 44.8% of the variance in a single latent trait extracted from psychosis, hostility, excitation, mannerism, negative symptoms, formal thought disorders, and psychomotor retardation and 40.9% in quality of life scores. GCoDe is significantly greater in deficit than in nondeficit schizophrenia. In conclusion, GCoDe mediates the effects of neuro-immune and neuro-oxidative toxicity on the phenome of (deficit) schizophrenia.
ARTICLE | doi:10.20944/preprints202302.0413.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: Hibiscus sabdariffa; antioxidants; nutraceuticals; phenolic compounds; functional foods
Online: 24 February 2023 (01:49:46 CET)
Secondary metabolites from Hibiscus sabdariffa have been used to prevent different diseases. Roselle Hibiscus is known for being rich in phenolic bioactive compounds. The extraction conditions are directly related to the chemical composition and then to the overall bioactivity of the extract. In this study, a Box Behnken experimental design has been used to optimize the antioxidant activity, considering four variables: the ethanol:water ratio, the temperature, the extraction time, and the solvent:solid ratio. The experiment comprises 27 experiments and 3 repetitions at the central point. The results are described by surface response analysis and a second-degree polynomial equation. The model explains 87% of the variation in the response. The maximum antioxidant activity is yielded when 1% solids are extracted in 35.5% ethanol at 60°C for 33 min. Finally, a nutritional functional supplement of 495 µmol Trolox Equivalent (TE) antioxidant capacity was prepared with the optimized extract.
ARTICLE | doi:10.20944/preprints202305.2068.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Sperm cryopreservation; semen quality; antioxidants; sperm motility; rams
Online: 30 May 2023 (07:35:22 CEST)
Glutathione (GSH) and melatonin (MLT) are two antioxidants that have been described as having a protective role against oxidative stress in several animal species, improving sperm quality and survival after cryopreservation. Since there is no knowledge on the simultaneous use of these two substances concerning its effects on ram semen cryopreservation, this study aimed to evaluate the effects of MLT, GSH, or their association, on in vitro parameters of ram semen after thawing. During eight weekly sessions, the semen from three Merino rams was pooled, divided into four aliquots, and diluted with an egg yolk-based semen extender without (control) and with antioxidants (MLT 1mM, GSH 5mM, and MLT 1mM + GSH 5mM). Diluted semen was evaluated before and after freezing process. Supplementation of fresh semen with GSH at 5 mM had a deleterious effect on total motility progressive (TPM), curvilinear velocity (VCL), straight-line velocity (VSL), average-path velocity (VAP), linearity (LIN), straightness (STR) and increased slow spermatozoon (%). MLT at 1 mM also has a negative effect on TPM, VSL, and STR in fresh semen. In thawed semen, 1 mM of melatonin increased the TPM regarding the group control. Also, the combination of both antioxidants attenuates the negative effect of GSH 5mM on TPM, VSL and BCF. These results indicate that 5mM GSH impairs or does not improve sperm kinetic parameters in fresh semen and suggest that melatonin when combined with GSH plays a protective role on these effects.
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.
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/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/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/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/preprints202305.1674.v1
Subject: Medicine And Pharmacology, Complementary And Alternative Medicine Keywords: antioxidants; anti-inflammatory activity; diabetes mellitus; Eryngium carlinae; phenolic compounds; rosmarinic acid
Online: 24 May 2023 (03:06:23 CEST)
Secondary metabolites such as flavonoids are considered to be promising in the treatment of NAFLD, which is one of the complications of diabetes due to oxidative stress and inflammation. Some plants, such as Eryngium carlinae, have been investigated with regard to their medicinal properties in in vitro and in vivo assays, showing favorable results for the treatment of various diseases such as diabetes and obesity. The present study examined the antioxidant and anti-inflammatory effects of the phenolic compounds present in an ethyl acetate extract of the inflorescences of Eryngium carlinae on liver homogenates and mitochondria from STZ-induced diabetic rats. Phenolic compounds were identified and quantified by UHPLC-MS. In vitro assays were carried out to discover the antioxidant potential of the extract. Male Wistar rats were administered with a single intraperitoneal injection of STZ (45 mg/kg) and were given the ethyl acetate extract at a level of 30 mg/kg for 60 days. Phytochemical assays showed that the major constituents of the extract were flavonoids; in addition, the in vitro antioxidant activity was dose-dependent with IC50 = 57.97 mg/mL and IC50 = 30.90 mg/mL in the DPPH and FRAP assays, respectively. Moreover, the oral administration of the ethyl acetate extract improved the effects of NAFLD, decreasing serum and liver TG levels and oxidative stress markers and increasing the activity of the antioxidant enzymes. Likewise, it attenuated liver damage by decreasing the expression of NF-κB and iNOS, which lead to inflammation and liver damage. These results suggest that the phenolic compounds of the ethyl acetate extract of E. carlinae have antioxidant, anti-inflammatory, hypolipidemic, and hepatoprotective activity.
ARTICLE | doi:10.20944/preprints202302.0021.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Thermal processing, Brassica vegetables, Kale, Broccoli sprout, Air frying, antioxidants
Online: 2 February 2023 (02:03:51 CET)
Brassica vegetables has demonstrated many health benefits over the years due to its composition of phenolic, flavonoid, and glucosinolate content. However, these bioactive molecules can be easily depleted during gastronomic operations. Therefore, a sustainable method which improves the phenolic content and antioxidant activity is required at large for the processors and consumers. Thermal processing has demonstrated as a method to improve the phenolic content and antioxidant status of Brassica vegetables. In the current study four different thermal processing methods, including freeze drying, sauteing, steam and air frying, were employed for five different Brassica vegetables, including kale, broccoli sprout, brussels sprout, red cabbage, and green cabbage. Total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities were assessed using radical scavenging activity (DPPH and ABTS•+), reducing power (FRAP), and chelating ability of the metal ions. Among tested, air frying at 160oC for 10 minutes showed the highest TPC, TFC, and antioxidant activity of the Brassica vegetables, while sautéing showed the lowest. Steam treatment was preferred over the freeze-drying treatment. Within the vegetables tested, both kale and broccoli sprout contained higher antioxidants properties in most processing treatment employed. Results also indicated that there is a strong correlation between TPC, TFC, and the antioxidant activity (p<0.05). This study indicates that air frying could be a choice of sustainable thermal processing method for improving biomolecules for Brassica vegetables.
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.
ARTICLE | doi:10.20944/preprints201910.0097.v1
Subject: Chemistry And Materials Science, Physical Chemistry Keywords: cyclodextrins; bryophyllum in vitro culture; inclusion complexes; kalanchoe; antioxidants; gallates.
Online: 9 October 2019 (10:22:37 CEST)
The rates of production of secondary metabolites obtained by employing conventional plant breeding may be low for practical purposes. Thus, innovative approaches for increasing their rates of production are being developed. Here, we propose the use of elicited suspension plant cultured cells (PSCC) with cyclodextrins (CDs) as an alternative method for the production of bioactive compounds from Bryophyllum species. For the purpose, we analyzed the effects of methyl--cyclodextrin and 2-hydroxypropyl--cyclodextrin on cell culture growth and on the intra- and extracellular production of phenols and flavonoids. Results clearly show that CDs enhance the biosynthesis of polyphenols by PSCC favoring their accumulation outside the cells. CDs shift the homeostatic equilibrium by complexing extracellular phenolics, causing stress in cells that respond by increasing the production of intracellular phenolics. We also analyzed the radical scavenging activity of the culture medium extracts against DPPH• radical, which increased with respect to the control samples (no added CDs). Our results suggest that both the increase in the production of polyphenols and their radical scavenging activity are a consequence of their inclusion in the CD cavities. Overall, based on our findings, CDs can be employed as hosts for increasing the production of polyphenols from Bryophyllum species.
ARTICLE | doi:10.20944/preprints201810.0590.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: biofortification; antioxidants; soilless culture; nutraceutical quality; enzymatic activity; plant resistance
Online: 25 October 2018 (05:22:51 CEST)
Selenium (Se) is an essential element of the human diet. Therefore, it is necessary to implement Se in agricultural fertilization, although it is not considered as an essential element for plants, Se provides benefits at the level of redox metabolism, increasing the resistance of plants to various stress factors. The increase of the availability of selenium with the use of biopolymer complexes was sought in Great Lakes lettuce grown in substrate pots treated with SeO2 (5 mg L Se), Cs-PAA + Se (5 mg L Se), and Cs-PAA. The redox metabolism was modified by increasing the enzymatic activity of glutathione peroxidase. The use of Cs-PAA + Se biopolymer complexes increase selenium up to 24 mg/Kg dry weight (DW) in plant tissues.
ARTICLE | doi:10.20944/preprints202305.0458.v1
Subject: Biology And Life Sciences, Horticulture Keywords: plant hormones; Citrus reticulata; shelf life; antioxidants; phenols content
Online: 8 May 2023 (05:37:55 CEST)
‘Arrayana’ mandarin fruits have a short postharvest life and are sensitive to chilling injury (CI) during cold storage. Brassinosteroids (BR) have been used as a sustainable technology to alleviate CI in fruits and improve postharvest quality. This study evaluated the effect of applying the 24-epibrasinolide analogue (EBR), at doses of 5 mg L-1; DI-31 analogue, at 5 and 10 mg L-1; and control, on the main physical and biochemical characteristics of 'Arrayana' mandarin stored at 4°C for 40 days and, subsequently, 7 days at room temperature (shelf life). The application of EBR and DI-31 analogues reduced the appearance of CI in the exocarp of 'Arrayana' mandarin fruits by reducing electrolyte leakage, maintaining membrane integrity, and increasing antioxidant activity and phenol content at the end of cold storage and shelf life. This was especially pronounced with 5 mg L-1 of EBR. Similarly, the BR maintained the postharvest quality of mandarins by reducing weight loss, respiratory intensity and chlorophyll degradation; increasing β-carotene; and maintaining titratable acidity, and soluble solids. Our research reports for the first time CI tolerance in Arrayana mandarin using natural (EBR) and spirostanic (DI-31), analogues and illustrates the tolerance functionality of the DI-31 analog on CI in fruit postharvest.
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.
ARTICLE | doi:10.20944/preprints201909.0095.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: deficit schizophrenia; antioxidants; bacteria; neuro-immune; inflammation; oxidative and nitrosative stress
Online: 9 September 2019 (09:00:44 CEST)
Background: Primary deficit schizophrenia (DS) is characterized by enduring negative symptoms and represents a qualitatively different disease entity with respect to non-deficit schizophrenia (NDS). No studies investigated the association between the enzyme paraoxonase 1 (PON1) and DS and its phenomenology. Methods: In this case-control study, Thai women and men, aged 18-65 years, were divided in DS (n=40) and NDS (n=40) and were compared to controls (n=40). PON1 activities against 4-(chloromethyl)phenyl acetate (CMPA) and phenylacetate were determined. Moreover, subjects were genotyped for their PON1 Q192R polymorphism and IgA levels responses directed to Gram-negative bacteria were measured. Results: DS is significantly associated with the QQ genotype and the Q allele as compared with NDS and controls. PON1 activities are significantly and inversely associated with negative symptoms, formal thought disorders, psychomotor retardation, excitation and DS. The presence of the Q allele is associated with increased IgA responses to Pseudomonas aeruginosa, Morganella morganii, and Pseudomonas putida as compared with RR carriers. Conclusions: The PON1 Q allele and lower PON1 activities especially against CMPA are associated with DS, indicating lowered quorum quenching abilities as well as lowered defenses against lipoperoxidation and immune activation. It is suggested that lowered PON1 activity in DS constitutes an impairment in the innate immune system which together with lowered natural IgM may cause lower immune regulation thereby predisposing towards greater neurotoxic effects of immune-inflammatory, oxidative and nitrosative pathways and Gram-negative microbiota.
REVIEW | doi:10.20944/preprints202007.0222.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: ROS; oxidative stress; catalytic antioxidants; superoxide dismutase; catalase; peroxidase; manganese; salen-type ligands; animal studies
Online: 11 July 2020 (03:30:41 CEST)
Manganosalen complexes are coordination compounds that possess a chelating salen-type ligand, a class of bis-Schiff bases obtained by condensation of salicylaldehyde and a diamine. They may act as catalytic antioxidants mimicking both the structure and the reactivity of the native antioxidant enzymes active site. Thus, manganosalen complexes have shown to exhibit superoxide dismutase, catalase, and glutathione peroxidase activities, and they could potentially facilitate the scavenging of excess ROS, thereby restoring the redox balance in the damaged cells and organs. Initial catalytic studies compared the potency of these compounds as antioxidants in terms of rate constants of the chemical reactivity against ROS, giving catalytic values approaching and even exceeding that of the native antioxidative enzymes. Although most of these catalytic studies lack of biological relevance, subsequent in vitro studies have confirmed the efficiency of many manganosalen complexes in oxidative stress models. These synthetic catalytic scavengers, cheaper than natural antioxidants, have accordingly attracted intensive attention for the therapy of ROS-mediated injuries. The aim of this review is to focus on in vivo studies performed on manganosalen complexes and their activity on the treatment of several pathological disorders associated with oxidative damage. This disorders, ranging from the prevention of fetal malformations to the extension of lifespan, include neurodegenerative, inflammatory and cardiovascular diseases, tissue injury, and other damages related to liver, kidney or lungs.
ARTICLE | doi:10.20944/preprints201809.0253.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: diabetes mellitus; ROS; carbohydrate metabolism; antioxidants; chronic unpredictable environmental stress
Online: 14 September 2018 (05:20:37 CEST)
Chronic unpredictable environmental stress (CUES) may induce predisposition to diabetes mellitus. This study investigates the role of CUES on impaired homeostasis. Stressed group mice (n = 20) were exposed to CUES for 16 weeks. Weekly body weight, feed consumption, feed efficiency ratio, fasting blood glucose were monitored. Plasma HbA1c, plasma cortisol, plasma epinephrine and plasma insulin, serum lipids, antioxidants and carbohydrate metabolizing enzymes activity were assessed along with DNA damage and histopathological examination of liver, kidney, pancreas, spleen and skeletal muscles. Fasting blood glucose levels & HbA1c in the stressed were significantly higher compared to control (p < 0.001). Serum lipids were found insignificantly higher in stressed mice compared to control. Body weights of the stressed mice and feed efficiency ratio were found significant (p < 0.001). Plasma corticosterone, plasma epinephrine, HOMA-IR was found to be significantly higher in the stressed group (p < 0.001). Plasma insulin level was found to be significantly lower in the stressed group (p < 0.001). Significant changes were observed in antioxidants level, carbohydrate metabolizing enzymes activity, peripheral tissues and DNA integrity. CUES initiates pathogenesis of diabetes.
REVIEW | doi:10.20944/preprints202006.0003.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: antioxidants; oxidative stress; prostate cancer; benign prostatic hyperplasia; biomarkers; pathways
Online: 2 June 2020 (09:27:21 CEST)
Introduction: Lowered thiol or sulfhydryl (-SH) groups and glutathione (GSH) metabolism may be associated with prostate cancer (PCa) and benign prostatic hyperplasia (BPH). The main objectives of this study were to systematically review and meta-analyze the evidence on the associations among -SH groups, GSH, GSH peroxidase (GPx), GSH reductase (GR) and GSH transferase (GST) and PCa/BPH. Methods: Four electronic databases were searched for studies that reported -SH and GSH variables in PCa/BPH and healthy controls (HC) and the data were meta-analyzed by calculating Hedges’s g with 95% confidence intervals. Results: Twenty studies were included in this meta-analysis including 800 PCa and 791 BPH patients and 592 HC. Total -SH (g=-1.750, -2.341/-1.159), GPx (g=-0.789, -1.234/-0.344), GSH (g=-2.219, -4.132/-0.305), and the combination of -SH, GPx, and GSH (g=-1.271, -1.271/-0.800) were significantly lower in PCa patients than in HC. -SH (g=-1.752, -3.123/-0.381) and the combination of -SH, GPx, and GSH (g=-0.813, -1.298/-0.327) were significantly lower in BPH patients than in HC. GPx was significantly lower in PCa than in BPH patients (g=-0.455, -0.896/-0.014). Heterogeneity levels were very high, but Egger’s test showed that none of the biomarkers showed significant publication bias. Conclusion: Thiol/GPx antioxidant defenses are significantly attenuated in patients with PCa while patients with BPH occupy an intermediate risk group position between PCa patients and HC. Those results suggest that reduced thiol-related antioxidant mechanisms play a crucial role in prostatic disorders, especially in PCa. Future research should examine whether thiols/GPx antioxidants are associated with the onset of PCa/BHP.
ARTICLE | doi:10.20944/preprints202009.0053.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: unstable angina, inflammation, neuro-immune, major depression, oxidative stress, antioxidants, atherogenicity
Online: 3 September 2020 (04:40:27 CEST)
Background. There is strong comorbidity between atherosclerosis (ATS) and depression which is attributed to increased atherogenicity, insulin resistance (IR), and immune and oxidative stress.Aim of the study. To examine the role of the above pathways and mu opioid receptor (MOR), β-endorphin, zinc, copper, vitamin D3, calcium, and magnesium in depression due to ATS / unstable angina (UA).Methods. Biomarkers were assayed in 58 controls and 120 ATS patients divided into those with moderate and severe depression according to the Beck Depression Inventory (BDI)-II score > 19 and > 29, respectively. Results. Neural network and logistic regression models showed that severe depression due to ATS/UA was best predicted by IL-6, UA, MOR, zinc, β-endorphin, calcium and magnesium and that moderate depression was associated with IL-6, zinc, MOR, β-endorphin, UA, atherogenicity, IR, and calcium. These neural networks yielded a significant discrimination of severe and moderate depression with an area under the ROC curve of 0.831 and 0.931, respectively. Using Partial Least Squares analysis, 66.2% of the variance in a latent vector extracted from the ATS/UA clinical features, BDI-II scores, atherogenicity, and IR could be explained by the regression on IL-6, IL-10, zinc, copper, calcium, MOR, and age. The BDI-II scores increased from controls to ATS to UA class III to UA class IV.Conclusions. Depression due to ATS/UA is a reflective manifestation of increased atherogenicity and IR, which are modulated by immune activation, aberrations in the endogenous opioid system, antioxidants, trace elements, and macrominerals.
ARTICLE | doi:10.20944/preprints202003.0292.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: temporal lobe epilepsy; antioxidants; oxidative stress; neuroimmune; major depression; schizophrenia
Online: 19 March 2020 (02:11:32 CET)
Background: Temporal lobe epilepsy (TLE) is the most common focal epilepsy subtype in adults and is frequently accompanied by depression, anxiety and psychosis. Aberrations in total paraoxonase (PON)1 status may occur in TLE and those psychiatric conditions. Methods: We examined paraoxonase (PON)1 status, namely Q192R PON1 genotypes and PON1 enzymatic activities, in 40 normal controls and 104 TLE patients, 27 without comorbidities, and 77 with comorbidities including mood disorders (n=25), anxiety disorders (n=27) and psychosis (n=25). Outcomes: CMPAase and arylesterase activities were significantly lower in TLE and mesial temporal sclerosis (MTS) with and without psychiatric comorbidities than in normal controls. The areas under the ROC curve of CMPAase were 0.893 (0.037) for TLE and 0.895 (±0.037) for MTS. Partial Least Squares (PLS) path analysis showed that there were specific indirect effects of PON1 genotype on TLE severity (p<0.0001) and psychopathology (p<0.0001), which were both mediated by lowered CMPAase activity, while arylesterase activity was not significant. The severity of TLE was significantly associated with psychopathology scores. Furthermore, PON1 CMPAase activity was inversely associated with Mini Mental State Examination scores. Interpretation: The severity of TLE and comorbidities are to a large extent explained by lowered PON1 enzyme activities and by effects of the Q192R genotype which are mediated by lowered CMPAase activity. Total PON1 status plays a key role in the pathophysiology of TLE, MTS and psychiatric comorbidities by increasing the risk of oxidative toxicity. PON1 enzyme activities are new drug targets in TLE to treat seizure frequency and psychiatric comorbidities.
ARTICLE | doi:10.20944/preprints202102.0347.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Ulmus pumila; salt stress; salt-tolerance; antioxidants; osmolytes; gas-exchange
Online: 17 February 2021 (09:22:23 CET)
Elevated salinity is one of the major environmental limitation factors of plant growth and development and salinity stress compromises the production and survival of plantation and urban forests and agricultural crops in the arid, semi-arid, and intertidal zones. Ulmus pumila, a salt- indigenous tree species in Asia and is widely deployed in salt-affected areas in China, and U.pumila is promising for multi-varietal forestry in plantation and urban forests. The comprehensive mechanism of the intraspecific salt tolerance is still not clear yet. Here, we investigated the physiological responses of the salinity stress based on the antioxidant enzyme activities, osmotic adjustments, and gas exchange among salt-tolerant U. pumila genotypes for 100 days under five different NaCl levels (0%, 0.3%, 0.5%, 0.7%, and 0.9% w/v) with natural surroundings and rain shade at age-2. Salt stress decreased height (HR), ground diameter (DR), and dry weight (biomass) were significantly different among genotypes. HR and performance indices were positively correlated with photosynthesis rate (Pn), apparent mesophyll conductance (AMC), and chlorophyll (CHLL) with (r= 0.7 - 0.8 ***), but were negatively related to the free proline, sugar, and protein accumulation (r=-0.5 ~ -0.7***). We found that high accumulation of sugars and more activities of SOD enzyme in leaf tissue contribute to the osmotic adjustment and ROS scavenging system under salinity treatment; the sugar content and SOD activity play key roles in U. pumila’s tolerance to salt stress, and are promising indicators for U. pumila species ex vitro selections. The ex vitro selection results align with the previous in vitro studies  and is promising for the MVF development.
REVIEW | doi:10.20944/preprints202008.0359.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Abiotic stress; Melatonin; Water stress; Drought; Waterlogging; Antioxidants; Stress signalling, phytohormones
Online: 17 August 2020 (10:19:52 CEST)
Water stress (drought and waterlogging) is drastic abiotic stress to plant growth and development. Melatonin, bioactive plant hormone, has been widely tested in drought situations in diverse plant species, while a few studies on the role of melatonin in waterlogging stress conditions have been published. In the current review, we analyze the bio-stimulatory functions of melatonin on plants under both drought and waterlogging stress. Melatonin controls the levels of reactive oxygen and nitrogen species and positively changes the molecular defense to improve plant tolerance against drought and waterlogging stress. Moreover, the crosstalk of melatonin and other phytohormones is a key element on plant survival under drought stress, while this relationship needs further investigation under waterlogging stress. In this review, we draw the complete story of water stress on both sides: drought and waterlogging through discussing the previous critical studies under both conditions. Moreover, we suggest several research directions, especially for waterlogging, which remains a big vague piece of melatonin and water stress puzzle.
REVIEW | doi:10.20944/preprints201812.0063.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Chaenomeles speciose; TCM; antioxidants; phytochemicals; anti-inflammation
Online: 5 December 2018 (07:40:27 CET)
Chaenomeles plants are adapted to diverse ecological zones particularly the temperate areas of Korea, Japan and China. In China, Chaenomeles speciosa mainly planted in Chongqing, Anhui and Hubei provinces. Most of the studies till date have been focused on the anti-inflammatory activities of C. speciosa fractions. The present study aimed to review the maximum literature reported for the presence of various phytochemicals in C. speciosa. In addition, the pharmacological properties of these chemical compounds of this plant shall also be discussed. The extracts of the various parts of the plant are rich in diversity of antioxidants, organic acids, phenolics, terpenoides and many different phytochemicals that bear strong anticancer, antioxidant, anti-viral, antibacterial properties, anti-inflammation, anti-hyperlipidemic, anti-hyperglycemic and anti-parkinson properties. C. speciosa fruits have broad scope in industry as well as in medicines. Not only the leaves and fruits of C. speciosa plant, but various other parts including roots, seeds, bark twigs, and flowers all have long history of clinical trials in curing many human ailments. However, the maximum accessible data concerning the chemical composition and their broad pharmacological properties of C. speciosa plant parts is pretty restricted that make it more appealing for indepth investigations.
REVIEW | doi:10.20944/preprints201610.0028.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mercury; antioxidants; cardiovascular diseases; cardiotoxicity; chelating agents
Online: 10 October 2016 (09:49:50 CEST)
Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence show that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.
ARTICLE | doi:10.20944/preprints202103.0487.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Major depression; Bipolar disorder; Metabolic syndrome; oxidative and nitrosative stress, antioxidants; biomarkers.
Online: 18 March 2021 (15:56:56 CET)
Background: There is a strong comorbidity between mood disorders and metabolic syndrome (MetS). Increased levels of reactive oxygen and nitrogen species (RONS) and nitro-oxidative stress toxicity (NOSTOX) partially underpin this comorbidity.Aims: To examine the associations of RONS/NOSTOX biomarkers with MetS after adjusting for the significant effects of mood disorders (major depression, and bipolar type 1 and 2), generalized anxiety disorder (GAD), tobacco use disorder (TUD), and male sex.Methods: The study included subjects with (n=65) and without (n=107) MetS and measured levels of superoxide dismutase 1 (SOD1), lipid hydroperoxides (LOOH), nitric oxide metabolites (NOx), malondialdehyde (MDA), and advanced oxidation protein products (AOPP) and computed z unit-weighted composite scores which reflect RONS/NOSTOX. The study included 105 patients with mood disorders, 46 with GAD, and 95 with TUD.Results: MetS was associated with increased levels of MDA and AOPP, independently from mood disorders, TUD, sex and GAD. Atherogenicity and insulin resistance (IR) were significantly associated with a NOSTOX composite score. Mood disorders, TUD, GAD, male sex and MetS independently contribute to increased RONS/NOSTOX. The RONS/NOSTOX profile of MetS was different from that of GAD, which showed increased SOD1 and NOx levels. TUD was accompanied by increased SOD1, LOOH and MDA, and male sex by increased LOOH and AOPP.Conclusions: MetS is characterized by increased lipid peroxidation with aldehyde formation and chlorinative stress, and atherogenicity and IR are strongly mediated by RONS/NOSTOX. Partially shared RONS/NOSTOX pathways underpin the comorbidity of MetS with mood disorders, GAD, and TUD.
REVIEW | doi:10.20944/preprints201703.0195.v1
Subject: Medicine And Pharmacology, Obstetrics And Gynaecology Keywords: melatonin; antioxidants; RNS; ROS; embryo development; DNA integrity; DNA oxidation; gene expression
Online: 27 March 2017 (10:04:31 CEST)
Oxidative and nitrosative stress are a common problem when manipulating gametes in vitro. In vitro development in mammalian embryos is highly affected by culture conditions, especially by reactive oxygen species (ROS) and reactive nitrogen species (RNS), because its absence or over production causes embryo arrest and changes in gene expression. Melatonin in gamete co-incubation during IVF has deleterious or positive effects depending on the concentration used in culture medium, demonstrating the delicate balance that must exist between antioxidant and pro-oxidant activity. Further research is needed to better understand the possible impact of melatonin on the different IVP steps in domestic animals, especially in seasonal breeds where this neuro-hormone system highly regulates its reproduction physiology.
ARTICLE | doi:10.20944/preprints201909.0290.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: microbial antioxidants; bioactive compounds; microwave extract; aspergillus flavus; rice, antioxidant compounds; free radical; phenolic compounds; temperatures
Online: 26 September 2019 (03:39:00 CEST)
The current study aims to study the optimal fermentation conditions for producing microbial bioactive compounds. The microwave parameters consist on 2450 MHz, and 500-watt for 20, 30, and 40 seconds. The solubility of solvents was tested for the extraction of antioxidant compounds from fermented rice (Koji) by A. flavus, Ethyl acetate was the best solvent used for extraction purposes. Antioxidant properties were differentiated by blocking the oxidation of the linoleic acid with an inhibition rate of 73.13% at a concentration of 200 mg/mL, in addition to increasing its effectiveness for free radical extraction and reduction strength by increasing concentrations gradually. The bond ability to irons was lower compared to the EDTA-2Na, in addition to the obtained total content corresponding to phenolic compounds in the ethyl acetate extract of fermented rice (Koji) by A. flavus was 232.11 mg, on the basis of galic acid/mg. The stability of the antioxidant compounds of the ethyl acetate extract of fermented rice (Koji) by A. flavus was also studied; showing stability under neutral conditions, as well as at high temperatures (185 °C during two hours). However, no stability was obtained under acidic and alkaline conditions.
REVIEW | doi:10.20944/preprints202301.0365.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: antioxidants; oxidative stress; reactive oxygen species; type 2 diabetes; pediatrics; redox; glycemic control; exercise; vitamin E; glutathione
Online: 19 January 2023 (15:10:23 CET)
The worldwide prevalence of type 2 diabetes (T2D) and prediabetes is rapidly increasing, particularly in children, adolescents, and young adults. Oxidative stress (OxS) has emerged as a likely initiating factor in T2D. The role of natural antioxidant products in combating T2D is best evaluated in the context of the complex physiological processes that modulate T2D-OxS such as glycemic control and exercise. The role of natural antioxidant compounds such as vitamin E in T2D must likewise be considered beyond their roles as inhibitors of OxS. In addition to antioxidant properties, vitamin E vitamers (tocopherols and tocotrienols) also exhibit distinct abilities to regulate cellular signal transduction pathways important to T2D progression. Most research on the role of vitamin E in T2D or prediabetes has been limited to tocopherols (Ts) but emerging trials with tocotrienols (T3s) show promise. Minimizing factors that induce chronic damaging OxS and maximizing natural antioxidant protective factors may provide a means of preventing or slowing T2D progression. This “optimal redox” (OptRedox) approach also provides a framework in which to discuss the potential benefits of natural antioxidant factors such as antioxidant products. Since early, effective intervention is critical, the OptRedox strategy would be optimally effective if implemented in the pediatric population.
ARTICLE | doi:10.20944/preprints202106.0095.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: antioxidants; Brassica juncea; ethylene; nitrogen assimilation; proline metabolism; sulfur assimilation
Online: 3 June 2021 (09:55:26 CEST)
In the present study, the potential of ethylene as ethephon (an ethylene source) was investigated individually or with a combination of the split dosage of nitrogen (N) and sulfur (S) soil treatments for the removal of damaging effects of salt stress (100 mM NaCl) in mustard (Brassica juncea L.). Plants were grown with 50 mg N plus 50 mg S kg−1 soil at sowing time and an equivalent dosage at 20 days after sowing ([N50 + S50]0d + [N50 + S50]20d). Ethephon at 200 μL L‒1 was applied to combined split dosage of N and S with or without NaCl. Plants subjected to NaCl showed a deceased in growth and photosynthetic characteristics as well as N and S assimilation, though, proline metabolism and antioxidants increased. The application of ethephon to plants grown with split N and S dosages significantly enhanced the photosynthetic efficiency by increasing the assimilation of N and S, improving the content of proline and induction of the antioxidant system with or without NaCl. The regulation of ethylene and/or split form N and S application may be the potential tools for overcoming salt stress effects in this species and in related Brassicaceae.
ARTICLE | doi:10.20944/preprints202005.0258.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: major depression; oxidative and nitrosative stress; antioxidants; inflammation; neuro-immune; biomarkers
Online: 15 May 2020 (16:52:52 CEST)
Background: Hypertension, atherogenicity and insulin resistance are major risk factors of cardiovascular disorder (CVD), which shows a strong comorbidity with major depression (MDD) and bipolar disorder (BD). Activated oxidative and nitrosative stress (O&NS), inflammatory pathways, and increased atherogenicity are shared pathways underpinning CVD and mood disorders. Methods: The current study examined the effects of lipid hydroperoxides (LOOH), superoxide dismutase (SOD), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), and malondialdehyde (MDA) on systolic (SBP) and diastolic (DBP) blood pressure in 96 mood disordered patients and 60 healthy controls. Results: A large part of the variance in SBP (31.6%) was explained by the regression on a z unit-weighted composite score (based on LOOH, AOPP, SOD, NOx) reflecting nitro-oxidative stress toxicity (NOSTOX), coupled with highly sensitive C-reactive protein, body weight and use of antihypertensives. Increased DBP was best predicted (23.8%) by body mass index and NOSTOX. The most important O&NS biomarkers predicting an increased SBP were in descending order of significance: LOOH, AOPP and SOD. Higher levels of the atherogenic index of plasma, HOMA2 insulin resistance index and basal thyroid-stimulating hormone also contributed to increased SBP independently from NOSTOX. Although there were no significant changes in SBP/DBP in mood disorders, the associations between NOSTOX and blood pressure were significant in patients with mood disorders but not in healthy controls. Conclusions: Activated O&NS pathways including increased lipid peroxidation and protein oxidation, which indicates hypochlorous stress, are the most important predictors of an increased BP, especially in patients with mood disorders.
REVIEW | doi:10.20944/preprints201809.0268.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: Liver; NAFLD; NASH; Biomarkers; Reactive Species; Oxidative Stress; Lipid Peroxidation; Antioxidants.
Online: 14 September 2018 (14:11:31 CEST)
Non-Alcoholic Fatty Liver Disease (NAFLD) is a term that covers a range of hepatic disorders involving fat deposits in the liver. NAFLD begins with simple steatosis and progresses into non-alcoholic steatohepatitis (NASH) characterised by inflammation, fibrosis, apoptosis, oxidative stress, lipid peroxidation, mitochondrial dysfunction and release of adipokines and pro-inflammatory cytokines. Oxidative stress and antioxidants are known to play a vital role in the pathogenesis and severity of NAFLD/NASH. A number of oxidative stress and antioxidant markers are employed in the assessment of the pathological state and progression of the disease. In this article, we review several biomarkers of oxidative stress and antioxidants that have been measured at clinical and experimental levels. The levels/ activity in various models reviewed are also included. Also included is a comprehensive description of oxidative stress, sources and contribution to the pathogenesis of NAFLD/NASH
REVIEW | doi:10.20944/preprints202208.0011.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: SBSJ; polyphenolic constituents; antioxidants; anti-inflammatory, chemoprevention; immunomodulation; anti-aging; adaptogen
Online: 1 August 2022 (08:06:10 CEST)
Across different cultures around the globe, human beings have historically depended largely on medicinal plants for managing diseases that have hitherto threatened their optimal health, survival, and longevity. Evidently, the health-derived benefits of medicinal plants can be strongly attributed to the presence of secondary metabolites, particularly polyphenols. The health-promoting effects of Sorghum bicolor supplement Jobelyn® (SBSJ) —a unique supplement derived from the leaf sheaths of a West African variety of Sorghum bicolor (L.) Moench—have also been ascribed to its high levels of polyphenols. This review seeks to gather and synthesize findings from various experimental and clinical studies on the health benefits of SBSJ in arthritis, cancer, chronic viral infections, stroke, anaemia, and aging. SBSJ has been reported to contain potent bioactive polyphenolic compounds with polyvalent biological activities, including antioxidant, anti-inflammatory, immunomodulatory, chemopreventive, and neuroprotective activities. Moreover, the probable benefits of SBSJ in chronic viral infections (e.g., HIV/AIDS and COVID-19) have been attributed to its potent anti-inflammatory and immunomodulatory activities. As this supplement is increasingly becoming one of the fastest-selling herbal medicines in Nigeria, there is a need for more robust studies (including clinical trials) in order to replicate and validate the prior insights gleaned from experimental studies.
REVIEW | doi:10.20944/preprints202109.0201.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: chronic fatigue syndrome; Myalgic Encephalomyelitis; inflammation; neuro-immune; oxidative and nitrosative stress; antioxidants
Online: 13 September 2021 (10:57:26 CEST)
There is evidence that chronic fatigue spectrum disorders (CFAS-D) including Myalgic Encephalomyelitis (ME), chronic fatigue syndrome (CFS) and chronic fatigue with physiosomatic symptoms including when due to comorbid medical disease are characterized by neuroimmune and neuro-oxidative biomarkers. The present study was performed to delineate the protein-protein interaction (PPI) network of CFAS-D and to discover the pathways, molecular patterns and domains enriched in their PPI network. We performed network, enrichment and annotation analysis using differentially expressed proteins and metabolics, which we established in CFAS-D patients. PPI network analysis revealed that the backbone of the highly connective CFAS-D network comprises NFKB1, CTNNB1, ALB, peroxides, NOS2, TNF, and IL6, and that the network comprises interconnected immune-oxidative-nitrosative and Wnt/catenin subnetworks. MultiOmics enrichment analysis shows that the CFAS-D network is highly significantly associated with cellular (antioxidant) detoxification, hydrogen peroxide metabolic process, peroxidase and oxidoreductase activity, IL10 anti-inflammatory signaling, and neurodegenerative, canonical Wnt, the catenin complex, cadherin domains, cell-cell junctions and TLR2/4 pathways; and the transcription factors NF-κB and RELA. The top-10 DOID annotations of the CFAS-D network include four intestinal, three immune system disorders, cancer and infectious disease. Custom GO term annotation analysis revealed that the CFAS-D network is associated with a response to a toxic substance, lipopolysaccharides, bacterium or virus. In conclusion, CFAS-D may be triggered by a variety of stimuli and their effects are mediated by aberrations in the cross-talks between redox, NF-κB, and Wnt/catenin signaling pathways leading to dysfunctions in multicellular organismal homeostatic processes.
REVIEW | doi:10.20944/preprints202205.0294.v2
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: general anesthesia; redox; inflammation; antioxidants; hypermetabolism; microRNAs; biomarkers; oxidative stress; Vitamin C
Online: 6 June 2022 (05:09:14 CEST)
Worldwide, the prevalence of surgery under general anaesthesia has increased significantly, on one hand because of modern anaesthetic and pain control techniques, and on the other hand because of better diagnosis and increased complexity of surgical technique. Together with the development of new concepts in the surgical field, the attention of researchers and clinicians turned to minimizing the impact of surgical trauma and offering minimal invasive procedures. This fact is due to the recent discoveries in the field of cellular and molecular mechanisms, that have revealed a systemic inflammatory and pro-oxidative impact that not only lasts in the perioperative period, but also impacts the long term, contributing to more difficult recovery, increased morbidity, and mortality, and finally a negative financial impact. Detailed molecular and cellular analysis have shown an overproduction of inflammatory and pro-oxidative species, that are responsible for an augmentation of the systemic inflammatory status and more difficult postoperative recovery. Moreover, it was shown that there are a series of changes in certain epigenetic structures, the most important being the microRNAs. Based on these findings, a series of modern, targeted therapeutic approaches have been proposed, with the final goal of blocking these mechanisms and reducing the redox state. Recent studies carried out had a positive clinical impact regarding antioxidant therapy and have shown that it can be used in the perioperative period with beneficial clinical impact. This review describes and details the most important molecular and cellular mechanisms that impact the surgical patient undergoing general anaesthesia, and it presents a series of antioxidant therapies that can reduce systemic inflammation.
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/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/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.
ARTICLE | doi:10.20944/preprints201907.0313.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Cistus incanus; wheat; bread; baking; physical properties; antioxidants
Online: 28 July 2019 (14:31:29 CEST)
Cistus incanus L. (CI) has been proposed as an innovative functional supplement of food products, and hence the present study aimed to evaluate the effect of the addition of dried CI on the properties of bread. Bread was prepared from white wheat flour supplemented with the addition of 1%, 2%, 3%, 4%, and 5% of ground CI. After the completion of baking process, various characteristics of the obtained bread product, such as yield, volume, porosity, acidity, color, and texture, were evaluated. In addition, total phenolic content (TPC), ABTS radical scavenging activity, CHEL chelating power, and ability to quench OH∙ radicals were measured. The results showed that the addition of CI to bread caused a reduction in the volume of bread, but texture of the crumbs was acceptable. Acidity and moisture content of bread were found to be increased following CI enrichment. Significant changes in the ash content and the color of bread crumbs were also observed. Bread incorporated with CI was characterized by significantly higher TPC and much higher antioxidant activity, as measured by ABTS, CHEL, and OH∙ radicals, compared to control bread. Supplementation of bread with 3% CI produced a product with desirable characteristics which was also favored by consumers.
REVIEW | doi:10.20944/preprints202103.0154.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: β-glucans; polysaccharides; flavonoids; anthocyanins; antioxidants; biological role of pigments; gene families
Online: 4 March 2021 (11:19:12 CET)
Cereal crops, such as oats and barley, possess a number of valuable properties that meet the requirements for functional diet components. This review summarized the available information about bioactive compounds of oat and barley grain. The results of studying the structure and physicochemical properties of the cell wall polysaccharides of barley and oat are presented. The main components of the flavonoids formation pathway are shown and data, concerning anthocyanins biosynthesis in various barley tissues, are discussed. Moreover, we analyzed the available information about structural and regulatory genes of anthocyanin biosynthesis in Hordeum vulgare L. genome, including β-glucan biosynthesis genes in Avena sativa L species. However, there is not enough knowledge about genes responsible for biosynthesis of β-glucans and corresponding enzymes and plant polyphenols. The review also covers contemporary studies about collections of oat and barley genetic resources held by VIR. This review intended to provide information on the processes of biosynthesis of biologically active compounds in cereals that will promote further researches devoted to transcription factors controlling expression of structural genes and their role in other physiological processes in higher plants. Found achievements will allow breeders to create new highly productive varieties with the desirable properties.
ARTICLE | doi:10.20944/preprints202010.0189.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: antioxidants for the treatment of ROS; new ester of eugenol; cosmetic formulations with clove water; skin penetration; Franz cell
Online: 9 October 2020 (08:59:05 CEST)
The main focus of this work is to extend the knowledge about the complexity of issues of oxidative stress. Natural compounds play a serious role in multiple aspects of both human, leading to clear health-promoting effects. This work is focused on the potential application cosmetic formulations containing including but not limited to of clove water and isolated clove oils on their aid in the control of the diseases. The aim of our work was to prepare to evaluate cosmetic formulations containing clove oil, eugenol or new eugenol ester derivative (eugenyl dichloroacetate - EDChA) but also cosmetic formulations containing the aqueous phase obtained after separation of essential oil following the clove buds steam distillation. To evaluate the antioxidants transdermal delivery system, in vitro permeation experiments in a Franz diffusion cell were performed using pig skin. The antioxidative capacity of the cosmetic formulations obtained was determined by the DPPH free radical reduction method. In the next stage, the antioxidant activity (DPPH, ABTS, and Folin–Ciocalteu methods) of the fluid that penetrated through pig skin and of the fluid obtained after skin extraction, were also evaluated. For comparison, studies of cosmetic formulation containing alone dichloroacetic acid (DChAA) were as well carried out. The obtained cosmetic formulations were characterized by of antioxidant activity estimated after 24 hours of conducting the experiment, which indicates long-term protection against reactive oxygen species (ROS) in the deeper layers of the skin. The results of this work contribute to the development of cosmetic formulations with antioxidant potential, emphasizing that the water phases are waste from the process of cloves steam distillation and are not used to prepare cosmetic formulations. The use of waste water from the clove buds steam distillation process is environmentally friendly and not allows us to waste, containing however valuable biologically active compounds (furfural, methyl salicylate, 4-allilofenol, eugenol, α- and β-caryophyllene, eugenyl acetate, β-caryophyllene oxide). Together, these results suggest that cosmetic formulations may be potential drug candidates for chemopreventive, antineoplastic and antimutagenic therapy.
ARTICLE | doi:10.20944/preprints202012.0457.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: deficit schizophrenia; neuro-immune; inflammation; oxidative and nitrosative stress; antioxidants; biomarkers; IgM; autoimmune
Online: 18 December 2020 (11:50:42 CET)
Recently, a breakdown of paracellular and vascular pathways and activated neuroimmune and oxidative pathways were established in (deficit) schizophrenia. The aim of the current study was to delineate a) the differences in these pathways between stable phase, first (FES) and multiple (MES) episode schizophrenia, and b) the pathways that determine the behavioral-cognitive-physical-psychosocial (BCPS)-worsening in FES/MES. This study included 21 FES and 58 FES patients and 40 healthy controls and measured indicants of serum IgA to C1q, and leaky gut, immune activation, and oxidative stress toxicity (OSTOX) biomarkers. We constructed a BCPS-worsening index by extracting a latent vector from symptomatic, neurocognitive, and quality of life data. FES patients showed significantly higher IgA to C1q, cadherin, catenin, plasmalemma vesicle-associated protein, and IgA/IgM to Gram-negative bacteria than FES patients and controls. In FES patients, the BCPS-worsening score was predicted (48.7%) by IgA to Klebsiella pneumoniae and lowered paraoxonase 1 activity. In MES patients, the BCPS-worsening score was explained (42.7%) by increased tumor necrosis factor-α, OSTOX, and number of episodes. In schizophrenia, 34.0% of the variance in the BCPS-worsening score was explained by IgA to K. pneumoniae, OSTOX, and number of episodes. Increased IgA to K. pneumoniae was the single best predictor of residual psychotic symptoms in FES and MES. This study delineated different mechanistic processes in FES, including breakdown of adherens junctions, bacterial translocation, and C1q circulating immune complexes; and FES, including immune and oxidative stress neurotoxic pathways. FES and MES comprise different staging subtypes, i.e., FES and MES with and without worsening.
REVIEW | doi:10.20944/preprints202305.1317.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: Starchy food; potato protease inhibitors; phytochemicals; antioxidants; cancer prevention
Online: 18 May 2023 (09:48:15 CEST)
Potato (Solanum tuberosum L) gradually becomes a stable food worldwide since it can be treated as practical nutritional supplement and antioxidant, as well as energy provider for human beings. Financially and nutritionally, cultivation and utility of potatoes is worthy enough attention of the world. To further explore functionality and maximize utilization of component parts, also to develop new products based on potato still be an ongoing issue. To maximize the benefits of potato and induce new high-value products while avoiding unfavorable properties of the crop has been a growing trend in food and medical areas. This review intends to summarize the factors that influence the changes in the key functional components of potatoes and discuss referred research focuses, then help further researchers to make efforts into. Afterwards, it summarizes the application of the latest commercial products and potential value of components existing in potato. Particularly, there are several main tasks for the next potato research: preparing starchy foods for special group of people and developing fiber-rich products to supply the dietary fiber intake as well as manufacturing bio-friendly and specific design films/coating in packaging industry; extracting bioactive proteins and potato protease inhibitors with high biological activity, and continue to build new commercial products based on potato protein and examine their health benefits. Noteworthy, the preservation methods play a key role in phytochemicals contents left in foods and potato performs superior to many common vegetables when meeting demand of mineral daily intake and alleviating mineral deficiencies.
ARTICLE | doi:10.20944/preprints202108.0083.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Antioxidants; Opuntia ficus indica; Opuntia dillenii; sperm quality; cryopreservation.
Online: 3 August 2021 (13:52:51 CEST)
Opuntia sp. contain antioxidant phytochemicals resistant to ROS damage, whose excess negatively affect fertilization. We investigate the activity of fruit extracts of O. dillenii and O. ficus indica (cv red and yellow) on sperm quality and cryopreservation. In the first experiment, we exposed the samples to extracts (50 µl) for 1 hour to then evaluate semen parameters (vitality, motility, acrosome reaction, DNA fragmentation and oxidative stress). The results showed a significant increase in the motility (86%±0.19 for OFI cv yellow, 82%±0.15 for OFI cv red and 90%±0.08 for O. dillenii) compared to the control (80%±0.17). Moreover, we noted a reduction of DNA fragmentation on treated (3%±0.03 in OFI cv yellow, 7%±0.09 in OFI cv red and 5%±0.07 in O. dillenii) than the control (40%±0.14). Furthermore, the oxidative stress was reduced after exposure to solutions (3.15mV in the control and 2.94mV in the treated). In the second experiment, 50 µl of solutions were added to the Freezing medium. After thawing, we observed an improvement in vitality and the number of intact acrosomes. Our results suggest that Opuntia sp. fruit extracts improve sperm quality, both before and after cryopreservation, optimizing the potential of fertilization of sperm cells.
REVIEW | doi:10.20944/preprints202106.0500.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: anticancer; antimicrobial; antioxidants; cancer signalling; citral; Cymbopogon; essential oil
Online: 21 June 2021 (10:31:35 CEST)
The prominent cultivation of lemongrass relies on the pharmacological incentives of its essential oil. The lemongrass essential oil (LEO) has a significant amount of citral (mixture of geranial and neral), isoneral, isogeranial, geraniol, geranyl acetate, citronellal, citronellol, germacrene-D, and elemol in addition to numerous other bioactive compounds. These components confer various medicinal activities to LEO including antifungal, antibacterial, antiviral, anticancer, and antioxidant properties. These attributes are commercially exploited in pharmaceutical, cosmetics, and food preservations industries. Furthermore, the employment of LEO in the treatment of cancer opens a new vista in the field of therapeutics. Although different LEO components have shown promising anticancer activities in vitro, these effects have not been assessed yet in humans. Further studies on the anticancer mechanisms exerted by lemongrass components are required. The present review intends to provide a timely discussion on the relevance of lemongrass extracts in cancer and health treatment, and in food industry applications.
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/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/preprints202304.0223.v1
Subject: Biology And Life Sciences, Horticulture Keywords: Solanum lycopersicum L.; chemical, organic and biological fertilization; antioxidants; minerals
Online: 11 April 2023 (10:42:00 CEST)
Tomato is considered the most important vegetable crop worldwide. Improving the nutritional value of fruits must be based on sustainable production in terms of varieties and fertilization management. This study aimed to improve the nutritional value (total soluble solids, acidity, lycopene, β-carotene, polyphenols, macro and microelements) of two tomato varieties (‘Cristal’ and ‘Siriana’) under three fertilization types (NPK chemical fertilizer, chicken manure and biological fertilizer with microorganisms) for the greenhouse. Primary metabolism compounds do not vary significantly according to the type of fertilizer used. The results for the antioxidant compounds showed a better effect of biological fertilization compared to chemical fertilizer and control unfertilized. The tomato fruits from the local cultivar (‘Siriana’) are richer in nutritional compounds such as rutin, regardless of the type of fertilization, which denotes a good ability to adapt to crop conditions. Tomato cultivars reacted positively to microbiological fertilization compare to chemical, thus producing nutritious fruits under sustainable management. Tomato fruits were richer in the quality of microelement contents.
ARTICLE | doi:10.20944/preprints202212.0486.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: Terminalia arjuna; Terminalone A; flavonoids; antibacterial; antioxidants; reactive oxygen specie
Online: 26 December 2022 (11:02:19 CET)
Terminalia arjuna possesses significant cardio protective, antidiabetic and antioxidant properties as these properties are described in Ayurveda. In the present study, three flavonoids were isolated through the separation and chromatographic purification of the whole plant material of T. arjuna. Spectroscopic characterization identified one of them as a new flavonoid “Terminalone A (1)” and two known flavonoids i.e. 6-hydroxy-2-(4-hydroxyphenyl)-7-methoxy-4H-chromen-4-one (2) and 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-one (3). The bioactivity studies showed considerable antibacterial and antioxidant (DPPH was used as a scavenger) potential for all the three compounds 1-3 where the compound 1 showed strong antibacterial and antioxidant activity.
REVIEW | doi:10.20944/preprints202012.0522.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: sickle cell disease; hemoglobin; oxidative stress; antioxidants; red blood cells
Online: 21 December 2020 (12:09:09 CET)
Sickle cell disease (SCD) is the most common hereditary disorder of hemoglobin (Hb) that affects approximately a millions people worldwide. It is characterized by a single nucleotide substitution on the β-globin gene, leading to the production of abnormal sickle hemoglobin with multi-system consequences. Mutated Hb leads to profound changes in: i) red blood cell metabolism and physiology; ii) endothelial signaling; and iii) immune response. Oxidative stress is an important hallmark of SCD. It plays a key role in the pathophysiology of hemolysis, vessel occlusion and the following organ damage in sickle cell patients. For this reason, reactive oxidizing species and the (end)-products of their oxidative reactions have been proposed as markers of both tissue pro-oxidant status and disease severity. Although more studies are needed to clarify their role, antioxidant agents have been shown to be effective in reducing pathological consequences of the disease by preventing oxidative damage in SCD, i.e. by decreasing the oxidant formation or repairing the induced damage. An improved understanding of oxidative stress will lead to targeted antioxidant therapies that should prevent or delay the development of organ complications in this patient population.
ARTICLE | doi:10.20944/preprints202005.0145.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: oxidative stress; antioxidants; biomarkers; deficit schizophrenia; inflammation; cytokines; neuro-immune
Online: 9 May 2020 (03:29:18 CEST)
Background: There is now evidence that schizophrenia and deficit schizophrenia are neuro-immune conditions and that oxidative stress toxicity (OSTOX) may play a pathophysiological role. Aims of the study: To compare OSTOX biomarkers and antioxidant (ANTIOX) defenses in deficit versus non-deficit schizophrenia. Methods: We examined lipid hydroperoxides (LOOH), malondialdehyde (MDA), advanced oxidation protein products (AOPP), sulfhydryl (-SH) groups, paraoxonase 1 (PON1) activity and PON1 Q192R genotypes, total radical-trapping antioxidant parameter (TRAP) as well as immune biomarkers in patients with deficit (n=40) and non-deficit (n=40) schizophrenia and healthy controls (n=40). Results: Deficit schizophrenia is characterized by significantly increased levels of AOPP and lowered -SH, and PON1 activity, while no changes in the OSTOX/ANTIOX biomarkers were found in non-deficit schizophrenia. An increased OSTOX/ANTIOX ratio was significantly associated with deficit versus non-deficit schizophrenia (Odds ratio=3.15, p<0.001). Partial least squares analysis showed that 47.6% of the variance in a latent vector extracted from psychosis, excitation, hostility, mannerism, negative symptoms, psychomotor retardation, formal thought disorders, and neurocognitive test scores was explained by LOOH+AOPP, PON1 genotype + activity, CCL11, tumor necrosis factor (TNF)-α, IgA responses to neurotoxic tryptophan catabolites (TRYCATs), whereas -SH groups and IgM responses to MDA showed indirect effects mediated by OSTOX and neuro-immune biomarkers. Discussion: Our findings indicate that with increasing overall severity of schizophrenia, neuro-immune and neuro-oxidative (especially protein oxidation indicating chlorinative stress) toxicities become more prominent and together with lowered antioxidant defenses and impairments in innate immunity-associated resilience against neurotoxic processes shape a distinct nosological entity, namely deficit schizophrenia.
ARTICLE | doi:10.20944/preprints202003.0472.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: chronic kidney disease; folic acid; inflammation; oxidative stress; antioxidants; biomarkers
Online: 31 March 2020 (23:32:43 CEST)
Introduction: Increased oxidative stress, including elevated homocysteine (Hcy) plasma levels, and lowered levels of antioxidants participate in the pathophysiology and progression of chronic kidney disease (CKD). Paraoxonase (PON)1 activity and folic acid are antioxidants which play a role in Hcy metabolism. However, there are no data whether, in CKD, treatment with folic acid improves glomerular filtration rate (GFR) through effects on PON1 activity and Hcy concentrations. Methods: In the current study, we determined PON1 genotypes and activity, Hcy and estimated GFR (eGFR) both before and after treatment with folic acid (5 mg/d) versus no treatment during three consecutive months in 113 outpatients with CKD classified into stages 4, 3b and 3a. Results: PON1 CMPAase and AREase activities were significantly lower in patients allocated to CKD stage 4 as compared with stages 3b and 3a. Treatment with folic acid significantly improved eGFR and increased levels of CMPAase and AREase in patients allocated to classes 4 and 3b, but not 3a. The improvement of eGFR was associated with increased CMPAase and AREase activities, while the latter were associated with increased levels of folic acid. Treatment with folic acid significantly reduced plasma Hcy levels and the Hcy/PON1 activity ratio. The effects of folic acid increasing PON1 activities were not mediated by changes in Hcy. Discussion: Treatment of CKD patients in early/intermediate stages of CKD patients improves oxidative stress by rebalancing the prooxidant (Hcy) / antioxidant (PON1 activities) ratio. Treatment with folic acid significantly improves eGFR and these effects are mediated via increased PON1 activities. Treatment with folic acid in phase G3b and G4 may reduce renal disease progression by enhancing antioxidant defenses.
ARTICLE | doi:10.20944/preprints202003.0416.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: menstrual cycle-related syndrome; neuroimmunomodulation; biomarkers; inflammation; oxidative stress; antioxidants
Online: 29 March 2020 (03:22:06 CEST)
Objective: To examine the associations between menstruation features and symptoms and hormone-immune-metabolic biomarkers. Methods: Forty-one women completed questionnaires assessing characteristic menstruation symptoms, duration of menstrual cycle and number of pads used/day and completed the Daily Record of Severity of Problems (DRSP) during the consecutive days of their menstrual cycle. Menses-related symptoms (MsRS) were computed from the sum of 10 pre- and post-menses symptoms and the menstruation blood and duration index (MBDI) was computed based on the daily number of pads and duration of menses. We assayed serum levels of various biomarkers at days 7, 14, 21, and 28 of the subjects’ menstrual cycle. Results: MBDI was significantly associated with a) MsRS including low abdominal cramps, and gastro-intestinal (GI) and pain symptoms (positively); b) plasma levels of haptoglobin (Hp), CCL5, insulin growth factor (IGF)-1, and plasminogen activator inhibitor (PAI)1 (all positively); and c) estradiol and paraoxonase (PON)1 arylesterase activity (both inversely). MsRS were significantly predicted by CCL5 and IGF-1 (both positively) and progesterone (inversely). Low-abdominal cramps, and gastro-intestinal and pain symptoms were associated with lower progesterone levels. The MBDI+MsRS score was significantly predicted by the cumulative effects of (in descending order of importance): Hp, IGF-1, PON1 arylesterase, estradiol and PAI. Conclusion: Menstruation-related features including estimated blood loss, duration of menses, cramps, pain and GI symptoms are associated with hormone-immune-metabolic biomarkers, which mechanistically may explain those features. Women with an increased MBDI+MsRS index ≥ 0.666 percentile may be considered to have menstruation-related distress, including dysmenorrhea symptoms.
ARTICLE | doi:10.20944/preprints202103.0462.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Antioxidants; ascorbate; Brassica juncea; cadmium stress; Cd defense and tolerance; glutathione; Indian mustard; sulfur assimilation.
Online: 18 March 2021 (09:29:59 CET)
The effect of four soil-applied sulfur [S; 100 mg S kg-1 soil (100S) and 200 mg S kg-1 soil (200S)] in different sources (elemental S, ammonium sulfate, gypsum or magnesium sulfate) in protecting mustard (Brassica juncea L. Czern & Coss.) from cadmium effects was studied. Based on the observed reduction in growth and photosynthesis in plants subjected to 100 and 200 mg Cd kg-1 soil, B. juncea cv. Giriraj was selected as the most Cd-tolerant among five cultivars (namely, Giriraj, RH-0749, Pusa Agrani, RH-406, and Pusa Tarak). Sulfur applied to soil mitigated the negative impact of Cd on sulfur assimilation, cell viability and photosynthetic functions, with a lower lipid peroxidation, electrolyte leakage, and contents of reactive oxygen species (ROS: hydrogen peroxide, H2O2, and superoxide anion, O2•−). Generally, added S caused a higher activity of antioxidant enzymes (ascorbate peroxidase, catalase and superoxide dismutase), and contents of ascorbate (AsA) and reduced glutathione (GSH), and increases in the activities of their regenerating enzymes (dehydroascorbate reductase and GSH reductase), as well as rises in S assimilation, biosynthesis of non-protein thiols (NPTs) and phytochelatins (PCs). Compared to the other S-sources tested, elemental S more prominently protected B. juncea cv. Giriraj against Cd-impacts by minimizing Cd-accumulation and its root-to-shoot translocation; decreasing cellular ROS and membrane damage, and improving Cd-chelation (NPTs and PCs), so strengthening the defense machinery against Cd. The results suggest the use of elemental S for favoring the growth and development of cultivated plants also in Cd-contaminated agricultural soils.
ARTICLE | doi:10.20944/preprints202011.0360.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Riboflavin transporter deficiency; motor neurons; mitochondria; energy metabolism; electron microscopy; antioxidants; SOD2; oxidative stress; neurodegeneration
Online: 12 November 2020 (18:14:17 CET)
Riboflavin transporter deficiency (RTD) is a childhood-onset neurodegenerative disorder characterized by sensorineural deafness and motor neuron degeneration. Since riboflavin plays key functions in biological oxidation-reduction reactions, energy metabolism pathways involving flavoproteins are affected in RTD. We recently generated iPSC lines from affected individuals as an in vitro model of the disease and documented mitochondrial impairment in these cells dramatically impacting cell redox status. In the present work, we extend our study to motor neurons (MNs), i.e., the cell type mostly affected in patients with RTD. Altered intracellular distribution of mitochondria was detected by confocal microscopic analysis, following immunofluorescence for superoxide dismutase 2 (SOD2), as a dual mitochondrial and antioxidant marker, and βIII Tubulin, as neuronal marker. We demonstrate significantly lower SOD2 levels in RTD MNs, as compared to their healthy counterparts. Mitochondrial ultrastructural abnormalities were also assessed by Focused Ion Beam/Scanning Electron Microscopy. Moreover, we investigated the effects of combination treatment using riboflavin and N-acetylcysteine, which is a widely employed antioxidant. Overall, our findings further support the potential of patient specific RTD models, and provide evidence of mitochondrial alterations in RTD-related iPSC-derived MNs, emphasizing oxidative stress involvement in this rare disease. We also provide new clues for possible therapeutic strategies, aimed at correcting mitochondrial defects, based on the use of antioxidants.
REVIEW | doi:10.20944/preprints202303.0500.v1
Subject: Medicine And Pharmacology, Ophthalmology Keywords: Oxidative stress and cell death; Reactive oxygen species; ROS; ROS cell death; autophagy; role of antioxidants; eye disease; cornea; lens; epithelium; retinal ganglion cells; retinal pigment epithelium; macular degeneration; antioxidants in the macula; oxidative stress prevention with antioxidants; lifestyle changes; digital eye strain; glaucoma; cataracts; dry eye disease; computer vision syndrome; digital eye strain; diabetic retinopathy; Vitamin A; Vitamin C; copper; glutathione; zinc; selenium; magnesium; blue light damage; UV light damage; blue light reactive oxygen species; autophagy; ferroptosis; ROS cell death; superoxide dismutase; optic nerve gliomas; food deserts; myopia; free radicals
Online: 29 March 2023 (03:33:55 CEST)
Increased screen time during the COVID-19 pandemic and the accelerated incorporation of technology into daily practices have directly contributed to the increased prevalence of eye disease. The human eye is not built for continual technological use and must adjust to exposure to digital screens. Overexposure to technology can result in eye strain and an increased risk of eye diseases such as myopia with complications later in life, including retinal tears, cataracts, and macular degeneration. As vision and ocular diseases become more prevalent, the study of eye diseases, including their causes and treatments, is especially relevant. There is a need to prevent ocular diseases before they become a burden to individuals, their families, and their communities by better understanding the pathophysiology of ocular diseases. Several ocular diseases are thought to be caused by imbalances in reactive oxygen species (ROS) and autophagy. ROS refers to a class of highly reactive oxygen-containing molecules that can undergo damaging reactions with other molecules in the cell. Autophagy is a cellular process of self-eating whereby damaged, harmful, or dead material in cells is broken down to maintain cellular homeostasis. This paper discusses the role of ROS and autophagy in the pathogenesis of computer vision syndrome (CVS), digital eye strain (DES), myopia, cataracts, glaucoma, diabetic retinopathy (DR), age-related macular degeneration (AMD), optic nerve crush injury (OCN), optic nerve gliomas, and retinoblastoma. Lifestyle changes such as limiting screen time, ensuring adequate exposure to evening sunlight, and using blue light protection measures or protective eyewear are important in the prevention of eye disease. Nutrition also contributes significantly to eye health. A balanced diet rich in vitamins and antioxidants may help to prevent ROS and autophagy imbalance-induced eye disease. Medical and surgical treatments become necessary when preventative measures fail. This paper also addresses how government measures to decrease the onset of eye disease, including targeted programs to increase access to fresh vegetables and fruits in food deserts, are a critical macro-level avenue to reduce eye disease prevalence in the US, which according to the National Eye Institute, costs $139 billion yearly.
ARTICLE | doi:10.20944/preprints202201.0244.v1
Subject: Chemistry And Materials Science, Electrochemistry Keywords: proton-coupled electron transfer; superoxide radical anion; antioxidants; cyclic voltammetry; electron spin resonance spectrum; pyrogallol
Online: 17 January 2022 (16:14:58 CET)
Abstract: Scavenging of electrogenerated superoxide radical anion (O2•−) by pyrogallol (PyH3) was investigated on the basis of cyclic voltammetry and in situ electrolytic electron spin resonance spectrum in N,N-dimethylformamide with the aid of density functional theory (DFT) calculations. Quasi-reversible dioxygen/O2•− redox coupe was modified by the presence of PyH3, suggesting that O2•− was scavenged by PyH3 through proton-coupled electron transfer (PCET) involving two proton transfer and one electron transfer. The DFT calculation suggested that the formation of hydrogen bond (HB) complex and the subsequent concerted-two-proton coupled electron transfer (2PCET) characterized by catechol moiety in PyH3 is plausible mechanism which embodies the superior kinetics of the O2•− scavenging by PyH3 as shown in the electrochemical results. Furthermore, it was clarified that three hydroxyl groups of PyH3 promote the formation of prereactive HB complex, in comparative analyses using related compounds, resulting the promotion of the O2•− scavenging.
ARTICLE | doi:10.20944/preprints202305.1254.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: antioxidants; chronic orofacial pain; oxidative-stress related genes; temporomandibular disorders; oral behavioural habits; single nucleotide polymorphism
Online: 17 May 2023 (14:15:27 CEST)
The frequency of selected polymorphisms, one in each gene coding for proteins with antioxidative properties (CAT, SOD2, GPX1, NQO1) was compared between patients suffering from pain-related temporomandibular disorders (TMDp;n=85) and control subjects (CTR;n=85). According to the Oral Behaviours Checklist score participants were divided into high-frequency parafunction (HFP;n=98) and low-frequency parafunction (LFP;n=72) groups. In addition, we have investigated the association of selected polymorphisms with participants' psychological (anxiety, depression) and psychosomatic (hypervigilance, somatosensory amplification) characteristics. Polymorphisms rs1001179, rs4880, rs1050450, rs689452 were genotyped using the genomic DNA extracted from buccal mucosa swabs and real-time TaqMan genotyping assays. No differences in genotype distribution between TMDp patients and control subjects were found. Still, TMDp patients who were homozygous for minor allele A, related to the GPX1 polymorphism rs1050450 reported significantly more waking-state oral behaviours compared to GA+GG genotype carriers (score: 30 vs. 23, p=0.019). Frequency of genotype AA for rs1050450 polymorphism was higher in HFP compared to LFP participants (14.3% vs. 4.2%, p =0.030). Most important predictors of waking-state oral behaviours were depression, anxiety, AA genotype (rs1050450) and female sex. Explored genetic factors were not found to be significant risk factors for either TMDp or sleep-related oral behaviours. The association of waking-state oral behaviours with selected gene polymorphisms additionally supports previous assumptions that the daytime bruxism is more closely linked to various stress manifestations, which might also be reflected through the variability related to cellular antioxidative activity.
ARTICLE | doi:10.20944/preprints202305.0228.v1
Subject: Chemistry And Materials Science, Physical Chemistry Keywords: rational design; antioxidants; electron transfer; hydrogen transfer; neuroprotection; AChE; COMT; MAOB
Online: 4 May 2023 (08:13:16 CEST)
Ferulic acid has numerous beneficial effects for human health, which are frequently attributed to its antioxidant behavior. In this report many of them are reviewed and 185 new ferulic acid derivatives are computationally designed, using the CADMA-Chem protocol. For the later, the chemical space was sampled and evaluated. To that purpose selection and elimination scores were used, which are built from a set of descriptors accounting for ADME properties, toxicity, and synthetic accessibility. After the first screening, 12 derivatives were selected and further investigated. Their potential role as antioxidants was predicted from reactivity indexes, directed related with the formal hydrogen atom transfer and the single electron transfer mechanisms. The best performing molecules were identified by comparisons with the parent molecule and two references: Trolox and alpha-tocopherol. Their potential as polygenic neuroprotectors was investigated through the interactions with enzymes directed related with the etiologies of Parkinson’s and Alzheimer’s diseases. They are acetylcholinesterase, catechol-O-methyltransferase, and monoamine oxidase B. Based on the obtained results, the most promising candidates (FA-26, FA-118, and FA-138) are proposed as multifunctional antioxidants with potential neuroprotective effects. The findings derived from this investigation are encouraging and might promote further investigations on these molecules.
REVIEW | doi:10.20944/preprints202012.0696.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: microalgae; carotenoids; chlorophylls; lipids; mycosporin-like amino acids; antioxidants; UV-screen
Online: 28 December 2020 (12:15:07 CET)
A prominent feature of stress-tolerant microalgae is their versatile metabolism allowing then to synthesize a broad spectrum of molecules with beneficial effects on many aspects of human body functioning. This is in line with the current understanding that many stress-induced deleterious processes in the human body and in photosynthetic cell are mediated by the same mechanisms such as free-radical attacks and lipid peroxidation. These related risks are kept at bay by optical screening of harmful UV, enzymatic ROS elimination systems, and potent low-molecular antioxidants. Microalgae synthesize a broad spectrum of compounds exerting antioxidant and/or UV-absorbing properties. In microalgae, they increase stress-resilience of these organisms. In human body, they exhibit photoprotective, antiaging, and sunscreen activities. Therefore, these algal metabolites were recognized as promising ingredients for innovative cosmetics and cosmeceutical formulations. Ever increasing effort is being invested into the search for new natural biologically active substances from microalgae. This trend is also fueled by the growing demand for natural raw materials for food, pharmaceuticals and cosmetology associated with the global transition to a "greener" lifestyle. Here, we review the currently accumulated knowledge about the main groups of cosmeceutical compounds from microalgae.
ARTICLE | doi:10.20944/preprints201810.0254.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: Solanum fruit juice; biochemical markers; chronic hepatitis C; oxidative stress; antioxidants
Online: 12 October 2018 (04:55:44 CEST)
Variations in liver metabolism as a result of hepatitis C virus have been established by numerous clinical trials. The use of antioxidants supplements has been reported to minimize the implication of this disease. In this regard, we examined the suitability of Solanum fruit juice, a natural source of vitamin C and citrus flavoniod as a precursor for the treatment of patients with chronic hepatitis C. Forty adult patients who were diagnosed with chronic hepatitis C and were under antiviral therapy were divided into two equal groups. Group 1 patients received their antiviral therapy with normal food and water and served as the control group while patients in group 2 were supplemented with Solanum fruit juice for eight consecutive weeks. Measurements for Anthropometric data, C reactive protein (CRP), atherogenic indices, biochemical parameters and activities of liver marker enzymes were recorded before and after eight weeks. No alterations were found in waist circumference, body mass and body fat following regular use of Solanum fruit juice. The serum levels of oxidative stress markers, LDL-cholesterol, total cholesterol, CRP and atherogenic indices decreased in the Solanum fruit juice group when compared to the control group. Moreover, the activities of the liver marker enzyme AST decreased in those who had high levels before the intervention. These results underscore the benefits of Solanum fruit juice in the diet of patients with HCV as a result of decreased cholesterol in blood serum, decreased inflammation, and increase in antioxidant capacity as well as maintaining body mass index. This clinical trial is registered at Pan African Clinical Trial Registry (www.pactr.org) with unique identification number PACTR201802003092138.
ARTICLE | doi:10.20944/preprints201711.0184.v2
Subject: Chemistry And Materials Science, Food Chemistry Keywords: Cistus incanus; Strandja; antioxidants; polyphenols; flavonoids; seasonality; buds; hard-coated seeds
Online: 2 January 2018 (11:21:12 CET)
The purpose of the present study is survey of extraction conditions and exploring antioxidant potential of the non-traditional for the Bulgarian ethno-medicine wild herb Cistus incanus widespread in Strandja Mountain. The influence of the extraction time (0–500 min) and solvent composition (0–50% ethanol in water) on the polyphenols, flavonoids yields and on antioxidant capacity of the extracts of leaves, stalks (wood parts) and buds mixture were studied. The antioxidant capacity (AOC) was evaluated by use of scavenging assays of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. Total polyphenol and flavonoid contents were quantified using UV–vis spectrometry. Optimal yield of desired components has been obtained with 30% ethanol in water solvent at 390th min extraction time. In addition, the influence of the seasonality (winter and summer Cistus incanus), and of the different areal parts - hard-coated seeds; buds, and mixture of leaves and stalks of the wild plant on the presence of polyphenols, flavonoids and AOC were investigated. Present work revealed the high values of the polyphenols, flavonoids, the high AOC not only in the summer leaves, but also found in the winter leaves, hard-coated seeds, buds and stalks. Based on the obtained results the Cistus incanus from Strandja mountain could be a new excellent source of natural antioxidants in food and pharmaceutical industries.
ARTICLE | doi:10.20944/preprints202112.0058.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: proton-coupled electron transfer; superoxide radical anion; antioxidants; cyclic voltammetry; electron spin resonance spectrum; tocopherol
Online: 3 December 2021 (15:01:26 CET)
Abstract: Elimination of superoxide radical anion (O2•−) by tocopherols (TOH), and related compounds was investigated on the basis of cyclic voltammetry and in situ electrolytic electron spin resonance spectral measurements in N,N-dimethylformamide (DMF) with the aid of density functional theory (DFT) calculations. Quasi-reversible O2/O2•− redox was modified by the presence of TOHs, suggesting that the electrogenerated O2•− was eliminated by α-, β-, γ-TOH through proton-coupled electron transfer (PCET), but not by δ-TOH. The structure–activity correlation of α-, β-, γ-, and δ-TOH characterized by methyl group on the 6-chromanol ring was experimentally confirmed, where the methyl group promotes the PCET mechanism. Furthermore, comparative analyses using some related chemical analogues suggested that methoxyl group of the 6-chromanol ring is required for a successful electron transfer (ET) to O2•− through the PCET. The electrochemical and DFT results in dehydrated DMF suggested that the PCET mechanism involves preceding proton transfer (PT) forming hydroperoxyl radical followed by a concerted PCET (ET–PT). The O2•− elimination by TOH proceeds efficiently along the net PCET mechanism involving one ET and two PTs.
ARTICLE | doi:10.20944/preprints202207.0340.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: dietary plants; medicinal plants; extraction; solvent; phytoconstituents; antioxidants; anti-nutrients; radical scavenging
Online: 22 July 2022 (13:16:10 CEST)
Sesamum indicum is considered an underutilized oil-bearing seed in the semi-arid regions of Ghana. Nonetheless, it is a promising source of food with both nutritional and therapeutic benefits. The aim of the present study was to evaluate the antioxidant properties S. indicum seeds using different extraction solvents. The seeds were obtained from the local farmers and prepared for analysis. The bioactive compounds present in the seeds were extracted using hexane, ethyl acetate, ethanol and water and their yields quantified. Total phenolic content (TPC), Condensed tannin content (TTC) and Total antioxidant capacity (TAC) , and DPPH radical scaveging assay were analyzed using standard methods. Antinutrients such as saponins, alkaloids, phytates and oxalates were also analyzed from the powdered seeds. Two chemometric methods; hierarchical cluster analysis (HCA) and Pearson correlation were employed to evaluate the interdependence of the various parameters to result in their antioxidant properties. The re-sults revealed that the solvents utilized had a significant impact on the extraction yield, phyto-chemical component concentration, and antioxidant activities. Hexane extracts of S. indicum seeds significantly exhibited the highest antioxidant activity (p < 0.05). It was marked with the highest TAC value of 232.6 ± 6.267 mg/g AAE and a strong DPPH scavenging activity with an IC50 of 52.81 ± 2.30 µg/mL. Correlations (p < 0.05) was established between TPC,CTC, TAC and DPPH radical scavenging activity) of the extracts. Antinutrients such as; phytate, oxalate, saponins and alkaloids were found to be 7.691 ± 0.8576, 1.501 ± 0.1375, 21.33 ± 4.619 and 317.33 ± 30.29 mg/g respectively. Data obtained suggest that S. indicum possess rich bioactive compounds that can be used in neutraceuticals and food products.
ARTICLE | doi:10.20944/preprints202105.0509.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: depression; mood disorders; inflammation; oxidative stress; nitrosative stress; neuro-immune; antioxidants; psychoneuroimmunology
Online: 21 May 2021 (09:36:47 CEST)
Type 2 diabetes mellitus (T2DM) is frequently accompanied by affective disorders with a prevalence of comorbid depression of around 25%. Nevertheless, the biomarkers of affective symptoms including depression and anxiety due to T2DM are not well established.Aims: This study was conducted to delineate the serum biomarkers predicting affective symptoms due to T2DM above and beyond the effects of insulin resistance and atherogenicity. Methods: The present study delineated the effects of serum levels of copper, zinc, β-arrestin-1, FBXW7, lactosylceramide (LacCer), serotonin, albumin, calcium, magnesium, IR and atherogenicity on severity of depression and anxiety in 58 men with T2DM and 30 healthy male controls. Severity of affective symptoms was assessed using the Hamilton Depression and Anxiety rating scales.Results: We found that 61.7% of the variance in affective symptoms was explained by the multivariate regression on copper, β-arrestin-1, calcium, and insulin resistance coupled with atherogenicity, while 44.4% of the variance in the latter was explained by copper, β-arrestin-1, LacCer (all positively) and calcium and FBXW7 (both negatively). Copper and LacCer (positive) and calcium and BXW7 (inverse) had significant specific indirect effects on affective symptoms which were mediated by insulin resistance and atherogenicity. Copper, β-arrestin-1, and calcium were associated with affective symptoms above and beyond the effects of insulin resistance and atherogenicity.Discussion: T2DM and affective symptoms share common pathways namely increased atherogenicity, insulin resistance, copper, and β-arrestin-1, and lowered calcium, whereas copper, β-arrestin-1, calcium, LacCer, and FBXW7 may modulate depression and anxiety symptoms by affecting T2DM.
REVIEW | doi:10.20944/preprints202112.0523.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Agriculture; antioxidants; Avocado; Cameroon; CAMAAY; deforestation; environment; food security; green gold; health; one health; sustainable development goals (SDGs); sustainability
Online: 31 December 2021 (13:47:40 CET)
Avocado (Persea americana Mill.) plant fruits are well-known for their high nutritional value, unique test, and healthy oil. It has a history of about 10,000 years. Avocado fruit offers many health benefits, and its production is rapidly increasing. The Food and Agriculture Organization (FAO)’s recent data suggest that the Avocados produced in the world in 2019 was twice that of 2010 (3778010 tons). Avocado’s global Gross Production Value was about 5.812 billion USD in 2018, and it is likely to increase rapidly because of the increasing demand for Avocado fruits. Avocado oil is also used in the cosmetic industry because of its therapeutic properties, and it boosts the economic value of the Avocado industry. Avocado fruits have a rough green-gold skin; however, fruits are called ‘the green gold’ because of their massive global demand in the worldwide market and a lucrative business. The cultivation of Avocado has tremendous potential in increasing the rural economy, rural agriculture-based employment and reducing the poverty rate of growers. On the other hand, the Avocado industry is highly criticised because of deforestation, massive water utilisation, polluting water bodies with insecticides and fertilisers, posing a threat to other plant species, and environmental pollution. However, it doesn’t preclude the importance of Avocado. Cameroon’s average temperature is about 23 °C, which is considered optimal for Avocado propagation and commercial cultivation. Cameroon Association of Active Youths (CAMAAY) want to explore the possibilities of engaging Cameroon youths in Avocado cultivation. This review is aimed to provide an overview of Avocado. The review also highlights Avocado cultivation related issues from one health and sustainability perspective in line with the global goals.
REVIEW | doi:10.20944/preprints202304.1245.v1
Subject: Biology And Life Sciences, Toxicology Keywords: Fluorescence; Image Cytometry; Cytomics; Reactive Oxygen Species; Antioxidants; Oxydative Stress; In Vitro Toxicology
Online: 30 April 2023 (03:08:04 CEST)
Oxidative stress has been implicated in cellular senescence and aging, as well as in the onset and progression of many diverse genetic and acquired diseases and conditions. The search for biomarkers of oxidative stress has become relevant to many biomedical fields using many different methods and approaches. Fluorescence methodology is advantageous because of its simplicity and high sensitivity. Fluorescent probes are frequently used to investigate the role of reactive oxygen species in oxidative stress in experimental or clinical settings, often involving the use of flow cytometry and related single-cell based technologies. To assess the specific role of reactive oxygen species in oxidative stress studies by cytometric methodologies, it is essential to detect and characterize these species accurately. However, the detection and quantitation of individual intracellular ROS is still a challenge, but different and complementary strategies may focus on other endpoints of oxidative stress. In this review we present and discuss briefly the limitations and perspectives of such approaches. Based on our results, we also provide recommendations for proper design of cytometric studies of oxidative stress in order to prevent or minimize experimental errors..
REVIEW | doi:10.20944/preprints202301.0532.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: natural products; plant extracts; Myrtus communis; medicinal plants; antimicrobial; antioxidants; antiviral; biofilm inhibition
Online: 7 February 2023 (03:33:29 CET)
Myrtus communis L., commonly known as true myrtle, is a medicinal plant native to the Mediterranean area. Since ancient times inhabitants of this area have been using it for its cultural and medicinal properties. Due to the high content of essential oil in its flowers, leaves and fruits, M. communis is an important medicinal and aromatic species from Myrtaceae family. Because of the presence of vast diversity of biomolecules in its aerial parts, it exhibits several biological properties of antioxidant, antimicrobial and anticancer. There has been increasing scientific interest in the field to understand the pleotropic effects of its extracts or essential oils on various ailments and diseases. This purpose of this review is to summarizes the chemical composition, traditional uses, and biological activities of M. communis L. leaves documented in numerous recent studies.
ARTICLE | doi:10.20944/preprints202009.0285.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Antioxidants; Biological System; Caffeic Acid; Callus culture; Chicoric Acid; Phenolics; Plant in vitro Cultures; Rosmarinic Acid; Thai Basil
Online: 13 September 2020 (12:18:48 CEST)
Thai basil is a renowned medicinal plant and a rich source of bioactive antioxidant compounds having several health benefits, with actions to prevent of cancer, diabetes and cardiovascular disease. Plant cell and tissue culture technologies can be routinely established as an important, sustainable and low-cost biomass source for the production of high-value phytochemicals. The current study aimed at developing an effective protocol for the production of Thai basil leaf derived callus cultures with sustainable and high production of biomass and antioxidants as an alternative of leaves production. MS basal medium with various concentrations of plant growth regulators (PGRs) compatible with nutraceutical applications (i.e., gibberellic acid (GA3) and 6-benzylaminopurine (BAP) either alone or in combination with naphthalene acetic acid (NAA)) were evaluated. Among all tested PGRs, the combination BAP:NAA (5 mg/L:1 mg/L) yield maximum biomass accumulation (fresh weight (FW): 190 g/L and dry weight (DW): 13.05 g/L) as well as enhanced phenolic (346.08 mg/L) production. HPLC quantification analysis indicated high productions of chicoric acid (35.77 mg/g DW) and rosmarinic acid (7.35 mg/g DW) under optimized callus culture conditions. Antioxidant potential was assessed using both in vitro cell free and in vivo cellular antioxidant assays. Maximum in vitro antioxidant activity DPPH (93.2 % of radical scavenging activity) and ABTS (1322 µM Trolox equivalent antioxidant capacity) was also observed for the extracts from callus cultures grown on optimal conditions. In vivo cellular antioxidant activity assay confirmed the effective protection against oxidative stress of the corresponding extract by the maximum inhibition of ROS and RNS production. Compared to commercial leaves, callus extracts showed higher production of chicoric acid and rosmarinic acid associated with higher antioxidant capacity. In addition, this biological system also has a large capacity for continuous biomass production, thus demonstrating its high potential for possible nutraceutical applications.
Subject: Biology And Life Sciences, Plant Sciences Keywords: medicinal plants; bioactive molecules; phenolic compounds; Oxidative stress; Antioxidants; chronic disorders; health maintenance; longevity
Online: 3 June 2019 (09:58:55 CEST)
Plants and its corresponding botanical preparations have been used for centuries due to their remarkable potentialities in both treatment and prevention of numerous affections. Hundreds of biologically active constituents are present in each whole plant matrice, working in synergism and conferring both its own protection against invaders and even providing promissory bioactive effects for human beings. The worldwide population has devoted increasing attention and preference by medicinal plants use for health promotion and disease prevention, and more recently for oxidative-stress related disorders protection. Indeed, oxidative stress-related disorders, like cardiovascular and (neuro) degenerative disorders, and even cancer have raised exponentially. Although oxidative stress is in itself intrinsic to our own metabolism, allarming sources of free radicals are daily affecting us. In fact, plant-derived bioactives present a broad spectrum of biological effects, and its antioxidant, anti-inflammatory and more recently anti-aging effects have been considered a hot topic among the medical and scientific community. Nonetheless, and although its numerous biological effects, it should not also be forgotten that some bioactive molecules are prone to oxidation and can even exert pro-oxidant effects. In this sense, the objective of the present review is to provide a detailed overview on plant-derived bioactives in oxidative stress-related disorders. Specifically, the role of phytochemicals as antioxidants and pro-oxidant agents is carefully addressed, as is its therapeutic relevance in disease prevention. Finally, an eye-opening look in overall evidence in humans is also ensured.
ARTICLE | doi:10.20944/preprints202010.0274.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: protein aggregation; inhibition of amyloid fibril formation; antioxidants; polyphenols; cystatin C; NAC and vitamin C; amyloid fibrils; stefin B aggregation; TEM
Online: 13 October 2020 (10:49:14 CEST)
We compare the effect on amyloid fibril formation by two homologous proteins from the family of cystatins, human stefin B (stB) and cystatin C (cysC) in presence of 3 polyphenols: curcumin, resveratrol and quercetin and 2 non-phenolic anti-oxidants: vitamin C (VitC) and N-acetyl cystein (NAC). Some of the experimental data have already been presented, here we compare, further discuss and highlight the results. The amyloid fibril formation was followed by ThT fluorescence and transmission electron microscopy. Inhibitory effects on amyloid fibrillation reaction depended on anti-oxidant class and concentration. The fact that different effect of polyphenols was observed with the two cystatins; Cur acted inhibitory on stB but not on cysC fibril formation, could be explained if the 3 polyphenols would not bind to the same binding site in the fibrils core. Other differences are pointed out and discussed. Synergistic effects of VitC and chosen polyphenols on amyloid fibrilllation of human stB have been explored and are reported here for the first time.
REVIEW | doi:10.20944/preprints202103.0143.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: antioxidants; alcohol metabolism; hepatoprotective; anti-ALD; mitochondrial dysfunction; mitochondria-targeted; oxidative stress; and cytochrome P450 2E1
Online: 4 March 2021 (09:13:05 CET)
Oxidative stress initiates and facilitates the disruption of the structural integrity of hepatic mitochondria, which leads to steatosis, steatohepatitis, fibrosis, and cirrhosis. It is now evident that mitochondrial dysfunction could be responsible for alcoholic liver disease (ALD). The challenge in treating ALD has been the limited availability of hepatoprotective agents and the lack of highly efficient delivery systems. Recent studies have shown that mitochondria-targeted therapies could address mitochondrial dysfunction (MD), which may greatly improve hepatoprotection and ALD treatment. This mini-review discusses the potential role of mitochondria-targeted antioxidants (MTAs) in the maintenance of hepatocellular integrity. This report also considers the mechanism of liver injury induced by alcohol and the progression of ALD from a mitochondrial oxidative damage perspective as well as the possible mechanistic actions of hepatoprotective antioxidants. Preliminary studies suggest the prospect of MTAs as anti-ALD and hepatoprotective agents.