ARTICLE | doi:10.20944/preprints202007.0363.v1
Subject: Biology And Life Sciences, Virology Keywords: Ebola virus; filovirus; lipid binding; matrix protein; VP24
Online: 17 July 2020 (06:00:08 CEST)
Viral protein 24 (VP24) from Ebola virus (EBOV) was first recognized as a minor matrix protein that associates with cellular membranes. However, more recent studies shed light on its roles in inhibiting viral genome transcription and replication, facilitating nucleocapsid assembly and transport, and interfering with immune responses in host cells through downregulation of interferon (IFN)-activated genes. Thus, whether VP24 is a peripheral protein with lipid binding ability for matrix layer recruitment has not been explored. Here we examined the lipid binding ability of VP24 with a number of lipid binding assays. The results indicated that VP24 lacked the ability to associate with lipids tested regardless of VP24 posttranslational modifications. We further demonstrate that the presence of the EBOV major matrix protein VP40 did not promote VP24 membrane association in vitro or in cells. Further, no protein-protein interactions between VP24 and VP40 were detected by co-immunoprecipitation. Confocal imaging and cellular membrane fractionation analyses in human cells suggested VP24 did not specifically localize at the plasma membrane inner leaflet. Overall, we provide evidence that EBOV VP24 is not a lipid binding protein and its presence in the viral matrix layer is likely not dependent on direct lipid interactions.
ARTICLE | doi:10.20944/preprints202005.0150.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: chaperone function; heat-shock proteins; lipid binding; phosphatidylserine; protein refolding
Online: 29 July 2020 (12:18:02 CEST)
HspA1A, a molecular chaperone, translocates to the plasma membrane (PM) of stressed and cancer cells. This translocation results in HspA1A’s cell-surface presentation, which renders tumors radiation insensitive. To specifically inhibit the lipid-driven HspA1A’s PM translocation and devise new therapeutics it is imperative to characterize the unknown HspA1A’s lipid-binding regions and determine the relationship between the chaperone and lipid-binding functions. To elucidate this relationship, we determined the effect of phosphatidylserine (PS)-binding on the secondary structure and chaperone functions of HspA1A. Circular dichroism revealed that binding to PS resulted in minimal modification on HspA1A’s secondary structure. Measuring the release of inorganic phosphate revealed that PS-binding had no effect on HspA1A’s ATPase activity. In contrast, PS-binding showed subtle but consistent increases in HspA1A’s refolding activities. Furthermore, using a Lysine-71-Arginine mutation (K71A; a null-ATPase mutant) of HspA1A we show that although K71A binds to PS with affinities similar to the WT, the kinetics of the binding are significantly different, probably because of the mutant’s inability to achieve specific conformations. These observations suggest a two-step binding model that includes conformational changes and strongly support the notion that the chaperone and lipid-binding activities of HspA1A are dependent but the regions mediating these functions do not overlap. These findings provide the basis for future interventions to inhibit HspA1A’s PM-translocation in tumor cells, making them sensitive to radiation therapy.
ARTICLE | doi:10.20944/preprints201807.0044.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: high and low molecular weight chitosan; lipid metabolism; liver lipid accumulation
Online: 3 July 2018 (12:13:20 CEST)
The present study examined and compared the effects of high- and low-molecular weight (MW) chitosan, a nutraceutical, on intestinal and liver lipid metabolism in rats fed with high-fat diet. Both high- and low-MW chitosan decreased liver weight, elongated small intestine, improved the dysregulation of blood lipids and liver fat accumulation, and increased fecal lipid excretion in high-fat diet-fed rats. Supplementation of both high- and low-MW chitosan significantly inhibited the decreased phosphorylated AMP-activated protein kinase (AMPK)α and peroxisome proliferator-activated receptor (PPAR)α protein expressions and the increased lipogenesis/cholesterogenesis-associated protein expressions (sterol regulatory element binding protein (SREBP)1c, SREBP2, and PPARγ) and the decreased apolipoprotein (Apo)E and microsomal triglyceride transfer protein (MTTP) protein expressions in the livers of high-fat diet-fed rats. Both high and low-MW chitosan supplementation could also suppress the increased MTTP protein expression and the decreased angiopoietin-like protein (Angptl)4 protein expression in the intestines of high-fat diet-fed rats. Comparison between high and low-MW chitosan, high-MW chitosan has a higher efficiency than low-MW chitosan on the inhibition of intestinal lipid absorption and the increase of hepatic fatty acid oxidation, which can improve liver lipid biosynthesis and accumulation.
ARTICLE | doi:10.20944/preprints201902.0240.v1
Online: 26 February 2019 (12:38:17 CET)
Biological membranes are fascinating. Santiago Ramón y Cajal, who received the Nobel prize in 1906 together with Camillo Golgi for their work on the nervous system, wrote “[..]in the study of this membrane[..] I felt more profoundly than in any other subject of study the shuddering sensation of the unfathomable mystery of life”. The visualization and conceptualization of these biological objects have profoundly shaped many aspects of modern biology, drawing inspiration from experiments, computer simulations, as well as from the imagination of scientists and artists. The aim of this review is to provide a fresh look on current ideas of biological membrane organization and dynamics by discussing selected examples across fields  The full quotation is “I must not conceal the fact that in the study of this membrane I for the first time felt my faith in Darwinism (hypothesis of natural selection) weakened, being amazed and confounded by the supreme constructive ingenuity revealed not only in the retina and in the dioptric apparatus of the vertebrates but even in the meanest insect eye. There, in fine, I felt more profoundly than in any other subject of study the shuddering sensation of the unfathomable mystery of life.” from the autobiography Recollections of My Life.
CASE REPORT | doi:10.20944/preprints201611.0134.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: GINKGO; hyperlipideamia; lipid profile
Online: 27 November 2016 (04:43:15 CET)
Hyperlipidemia case was described as a rise of lipid profile or lipoproteins in the blood. This study describe briefly investigate the reducing hyperlipideamia impact of Ginkgo biloba on the level of lipid profile.
REVIEW | doi:10.20944/preprints202209.0095.v2
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: endothelium; vascular biology; lipid; angiogenesis
Online: 28 November 2022 (02:22:27 CET)
The endothelium is a monolayer of cells lining the inner blood vessels. Endothelial cells (ECs) play indispensable roles in angiogenesis, homeostasis, and immune response under normal physiological conditions, and their dysfunction is closely associated with pathologies such as cardiovascular diseases. Abnormal EC metabolism, especially fatty acid (FA) dysfunctional metabolism, contributes to the development of many diseases including pulmonary hypertension (PH). In this review, we focus on discussing the latest advances in FA metabolism in ECs under normal and pathological conditions with an emphasis on PH. We also highlight areas of research that warrant further investigation.
ARTICLE | doi:10.20944/preprints202207.0435.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Mms6; ferric reductase; lipid; bicelles
Online: 28 July 2022 (09:00:18 CEST)
Magnetosomes of magnetotactic bacteria consist of magnetic nanocrystals with defined morphologies enclosed in vesicles originated from cytoplasmic membrane invaginations. Although many proteins are involved in creating magnetosomes, a single magnetosome protein, Mms6, can direct the crystallization of magnetite nanoparticles in vitro. The in vivo role of Mms6 in magnetosome formation is debated and the observation that Mms6 binds ferric and not ferrous iron raises the question of how Mms6 could promote the crystallization of magnetite, which contains both ferric and ferrous iron. Here we show that Mms6 is a ferric reductase that reduces ferric to ferrous iron using NADH and FAD as electron donor and cofactor, respectively. Reductase activity is elevated when Mms6 is integrated into either liposomes or bicelles. Analysis of Mms6 mutants suggests that the C-terminal domain binds iron and the N-terminal domain contains the catalytic site. Although Mms6 forms multimers that involve C-terminal and N-terminal domain interactions, a fusion protein with Mms6, which remains a monomer, displays reductase activity, which suggests that the catalytic site is fully in the monomer. These results are consistent with a hypothesis that Mms6, a membrane protein, promotes the formation of magnetite by a mechanism that involves reducing iron.
ARTICLE | doi:10.20944/preprints202207.0253.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: LMNA; AMPK; lipid metabolism; cancer
Online: 18 July 2022 (08:59:58 CEST)
Laminopathies are a spectrum of diseases caused by LMNA mutations. In familial partial lipodystrophy of Dunnigan (FPLD), LMNA plays role in the differentiation and development of adipocytes and lipid metabolism. Changes in LMNA predict not only the differentiation of adipose-derived mesenchymal stem cells (AD-MSCs) but also the transformation of cancer cells. Hence, our in-depth study aimed to identify the molecular connection between disordered lipid metabolism and hepatic carcinogenesis. We first discovered significant positive correlations between pLMNA and two key rate-limiting enzymes in de novo fatty acid synthesis, acetyl-CoA-carboxylase 1 (ACC1) and fatty acid synthase (FASN), in the liver tissue but not in adipose tissue of obese model rats. Moreover, LMNA knockdown (KD) in rat AD-MSCs prevented the differentiation and maturation of adipocytes. To clarify the mechanistic relationship with lipogenesis, gain- and loss-of-function experiments in which functional changes and the related molecular pathways were investigated in a normal hepatocyte line (7701 cells). Adenosine 5'-monophosphate activated protein kinase α (AMPKα) was found to be activated by abnormalities in the LMNA structure under conditions of LMNA deletion, farnesyltransferase inhibitor (FTI) treatment and LMNA mutations associated with clinical FPLD pathogenic phenotype. Active AMPKα could directly phosphorylate ACC1 and thus inhibit lipid synthesis but induced glycolysis in both HCC cells and normal cells. The HCC cells could not survive with LMNA knockout (KO) or even KD. Lonafarnib (an FTI) combined with low-glucose conditions significantly decreased the proliferation of HepG2 and MHCC cells by inhibiting glycolysis and the maturation of prelamin A.
ARTICLE | doi:10.20944/preprints202203.0259.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: kidney; renal; lipid; fast MRSI
Online: 18 March 2022 (02:59:02 CET)
A reliable and practical renal-lipid quantification and imaging method is needed. Here, the feasibility of an accelerated MRSI method to map renal fat fractions (FF) at 3T and its repeatability were investigated. A 2D density-weighted concentric-ring-trajectory MRSI was used to accelerate acquiring 48×48 voxels (each of 0.25 ml spatial-resolution) without respiratory navigation implementations. The data was collected over 512 complex-FID timepoints with a 1250 Hz spectral bandwidth. The MRSI sequence was designed with a metabolite-cycling technique for lipid-water separation. The in vivo repeatability performance of the sequence was assessed by conducting a test-reposition-retest study within healthy subjects. The coefficient of variation (CV) in the estimated FF from the test-retest measurements showed a high degree of repeatability of the MRSI-FF (CV= 4.3 ±2.5%). Additionally, the matching level of spectral signature within the same anatomical region was also investigated, and their intrasubject repeatability was also high, with a small standard deviation (8.1 ±6.4%). The MRSI acquisition duration was ~3 minutes only. The proposed MRSI technique can be a reliable technique to quantify and map renal metabolites within a clinically acceptable scan time at 3T that supports the future application of this technique for the non-invasive characterization of heterogeneous renal diseases and tumors.
ARTICLE | doi:10.20944/preprints201704.0085.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: lipid extracted microalgae, isoprenoids, detoxification
Online: 14 April 2017 (09:11:15 CEST)
Microalgae are recognized as a third generation feedstock for biofuel production due to its rapid growth rate and lignin-free characteristic. In this study, the lipid extracted microalgae biomass residues was used as the material to produce isoprene, α-pinene and β-pinene with the engineered E. coli strain. We adopted an optimal sulfuric acid hydrolysis method to convert holocellulose into fermentable sugar efficiently (6.37 g/L) and explored a novel detoxification strategy (phosphoric acid/calcium hydroxide) to remove inhibitors notably. 55.32 % acetic acid, 99.19 % furfural and 98.22 % 5-HMF were cut down with the phosphoric acid/calcium hydroxide method, and the fermentation concentration of isoprene (223.23 mg/L), α-pinene (382.21 μg/L) and β-pinene (17.4 mg/L) using the detoxified hydrolysate as the carbon source account for approximately 86.02 %, 90.16 % and 88.32 % of those produced by the engineered E. coli strain fermented on pure glucose, respectively.
ARTICLE | doi:10.20944/preprints202310.2081.v1
Subject: Biology And Life Sciences, Aquatic Science Keywords: fish; canning; cold storage; lipid oxidation; lipid hydrolysis; fatty acid profile; colour changes; trimethylamine; degradation
Online: 31 October 2023 (12:36:19 CET)
The combined effects of the thermal processing (i.e., sterilisation treatment) and the prior frozen storage time (3 or 6 months at –18 ºC) on the quality loss in canned Atlantic horse mackerel (Trachurus trachurus) were determined. Thus, the sterilisation step led to a remarkable (p<0.05) formation in canned fish muscle of fluorescent compounds, free fatty acids (FFAs) and trimethylamine and to an increase of the L* and b* colour parameters; meantime, a decrease (p<0.05) of the total ω3 FA/total ω6 FA ratio and the a* colour value were detected. The prior frozen storage period led to an increased (p<0.05) lipid oxidation (peroxide, thiobarbituric acid reactive substance and fluorescent compound formation) and hydrolysis (FFA formation) development and to increased L* and b* colour values in the corresponding canned samples; additionally, a lower (p<0.05) polyene index and phospholipid content were observed in canned fish previously subjected to frozen storage. In most indices, physico-chemical changes related to quality loss were found higher if the previous storage period was increased. According to the marked effects of the sterilisation step and the prior frozen storage period, optimisation of such processing conditions is recommended to maximise the quality of canned horse mackerel.
REVIEW | doi:10.20944/preprints202308.1370.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: gucagon; glucose; lipid; amino acid; hyperglucagonemia
Online: 21 August 2023 (03:07:14 CEST)
In the context of type 2 diabetes (T2DM), fasting and postprandial hyperglucagonemia have long been linked to the disease's development and progression. However, recent studies have brought to light the positive impact of glucagon-agonists on lipid metabolism and energy homeostasis. This review delves into the intricate relationship and underlying mechanisms between glucagon and nutrient composition, which may hold promise in devising novel therapeutic approaches for T2DM management.
REVIEW | doi:10.20944/preprints202302.0142.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: vaccine; mRNA; COVID 19; lipid nanoparticles
Online: 8 February 2023 (09:55:30 CET)
In the recent days, lipid nanoparticles have been successfully emerged as one of the most advanced technology for highly efficient in vivo delivery of exogenous mRNA, especially for delivery of COVID-19 vaccines. For the vaccines to be successful or protective, they require highly efficient mRNA delivery systems. However, developing effective, translatable vaccines with better safety against some of the SARS‐CoV‐2 variants is still a challenge. Lipid nanoparticles (LNPs) are composed of four different types of lipids including ionizable lipids, helper or neutral lipids, cholesterol and polyethylene glycol (PEG) attached lipids. In this review, we present recent advancements and insights in designing the advanced LNPs and their composition and properties, with a subsequent discussion on the development of COVID-19 vaccines. In particular, as the ionizable lipids are most important drivers for complexing the mRNA and in vivo delivery, the role of ionizable lipids in mRNA vaccines discussed in detail. Furthermore, the use of LNPs as effective delivery vehicles for vaccination, genome editing, and protein replacement therapy were discussed. Finally, expert opinion of LNPs for mRNA vaccines were discussed which might address the future challenges in the development of mRNA vaccines employing highly efficient LNPs using novel set of ionizable lipids.
REVIEW | doi:10.20944/preprints201805.0410.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: biosensors; lipid membranes; potentiometry, graphene electrodes
Online: 28 May 2018 (13:38:53 CEST)
This review provides informations and details for the fabrication of biosensors that are composed from lipid membranes and have been utilized and applied to rapidly detect food toxic compounds, environmental pollutants and analytes of clinical interest. Biosensors based on polymeric lipid membranes have been used to rapidly detect a wide range of these analytes and offer several advantages such as fast response, high sensitivity and selectivity, can be portable for in the field applications, and small size. A description of the construction of these devices and their applications for the rapid detection of food toxic substance, environmental pollutants and analytes of clinical interest is provided in this review.
COMMUNICATION | doi:10.20944/preprints202307.1638.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: recombinant spike protein; human PBMCs; lung microvascular endothelial cells; cytokines; chemokines; lipid droplets; lipid metabolism genes
Online: 25 July 2023 (08:14:12 CEST)
Intracellular lipid droplets (LDs) can occur in response to inflammation, metabolic stresses, and other physiological/pathological processes. Herein, we investigated whether spike proteins of SARS-CoV-2 induce LDs in human peripheral blood mononuclear cells (PBMCs) and in pulmonary microvascular endothelial cells (HPMEC). PBMCs or HPMEC were incubated alone or with endotoxin-free recombinant variants of trimeric spike glycoproteins (Alpha, Beta, Delta, and Omicron, 12 µg/ml). Afterwards, cells were stained with Oil Red O for LDs, cytokine release was determined by ELISA, and the gene expression was analyzed by real-time PCR using TaqMan assays. Our data show that spikes induce LDs in PBMCs but not in HPMEC. In line, in PBMCs spike proteins lower expression of genes involving lipid metabolism and LDs formation, such as SREBF1, HMGCS1, LDLR, and CD36. On the other hand, PBMCs exposed to spikes for 6 or 18 h did not increase in IL-1β, IL-6, IL-8, MCP-1, and TNFα release or expression as compared to non-treated controls. Thus, spike-induced LDs formation in PBMCs seems to be not related to cell inflammatory activation. Further detailed studies are warranted to investigate in which specific immune cells spikes induce LDs, and what are pathophysiological mechanisms and consequences of this induction in vivo.
ARTICLE | doi:10.20944/preprints201810.0008.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: perilipins, milk lipid globules, human breast milk, lipid content, tandem mass spectrometry, ultra-high performance liquid chromatography
Online: 1 October 2018 (12:18:46 CEST)
Objective: Lipids are secreted into milk as bilayer-coated structures: milk lipid globules (MLGs). Adipophilin (ADRP) and perilipin 3 (TIP47) are associated with MLGs in human breast milk; however, the role of these proteins in milk lipid secretion is not fully understood. The aim of the study was to investigate levels of ADRP, TIP47 and total lipid content in human breast milk, their mutual correlations and dynamics during lactation. Research Methods & Procedures: Milk samples from 22 healthy lactating women (Caucasian, Central European) were collected at five time points during lactation (1–3, 12–14, 29–30, 88–90 and 178–180 days postpartum). Mass spectrometry-based method was used for quantification of ADRP and TIP47 in the samples. The gravimetric method was used to determine milk total lipid content. Results: We observed distinctive trends in ADRP, TIP47 levels and lipid content in human breast milk during the first 6 months of lactation. We also found a significant association between lipid content and ADRP, lipid content and TIP47, and ADRP and TIP47 concentrations in breast milk at all sampling points. Moreover, we derived an equation for estimating the mean lipid content of milk based on ADRP concentration in human breast milk. Conclusions: A mass spectrometry-based method was developed for quantifying ADRP and TIP47 in human breast milk. Strong mutual correlations were found between ADRP, TIP47 and total lipid content in human breast milk.
REVIEW | doi:10.20944/preprints202311.0366.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: IBD; IECs; Lipid intake; Stem cells; Inflammation
Online: 7 November 2023 (07:10:30 CET)
Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, is a disease of chronic inflammatory conditions of the intestinal tract due to disturbance of the inflammation and immune system. Symptoms of IBD include abdominal pain, diarrhea, bleeding, reduced weight, and fatigue. In IBD, the immune system attacks the intestinal tract's inner wall, causing chronic inflammation and tissue damage. In particular, IL-6 and IL-17 act on immune cells, including T cells and macrophages, to amplify the immune responses so that tissue damage and morphological changes occur. Of note, excessive calorie intake and obesity also affect the immune system due to inflammation caused by lipotoxicity and changes in lipids supply. Similarly, individuals with IBD have alterations in liver function after sustained high-fat diet feeding. In addition, excess dietary fat intake, along with alterations in primary and secondary bile acids in the colon, can affect the onset and progression of IBD because inflammatory cytokines contribute to insulin resistance; the factors include the release of inflammatory cytokines, oxidative stress, and changes in intestinal microflora, which may also contribute to the disease progression. However, interfering with de novo fatty acid synthase by deleting the enzyme acetyl-CoA-carboxylase 1 in intestinal epithelial cells leads to the deficiency of epithelial crypt structures and tissue regeneration, which seems to be due to Lgr5+ intestinal stem cell function. Thus, conflicting reports exist regarding high-fat diet effects on IBD animal models. This review will focus on the pathological basis of the link between dietary lipids intake and IBD and cover currently available pharmacological approaches.
REVIEW | doi:10.20944/preprints202311.0375.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lipid; apolipoprotein; circadian clock; brain; neuron; hormone
Online: 6 November 2023 (17:42:18 CET)
The circadian clock is a 24-hour cycle within the body that regulates various factors, including sleep, body temperature, and hormone secretion. It allows the body to adjust to the light and dark cycle. Disruptions to the circadian rhythm are important risk factors for many diseases, including neurodegenerative illnesses. The central clock is controlled by the clock genes in the suprachiasmatic nucleus (SCN) of the brain, and one of the main functions of the circadian clock is to regulate lipid metabolism. There has been a lack of investigation on the circadian regulation of lipid metabolism-related apolipoprotein genes in the brain; thus, this study sought to summarize the rhythmic expression of clock genes and lipid metabolism-related apolipoprotein genes within the SCN of Mus musculus. Out of the 20 apolipoprotein genes that were studied by the published database, all 9 genes were highly expressed in the SCN. Most of the 6 genes showed rhythmic expression in the brain of mice, suggesting that the master clock might regulate them. The results, therefore, reveal a potential target for preventing and treating circadian disorders. We summarized most studies of lipid-related apolipoprotein genes within limited locations of the SCN and brain to further understand how disordered cerebral lipid metabolism causes multiple brain diseases and disorders. We reviewed recent studies, determined the unexplored questions, and identified a potential direction for further research.
ARTICLE | doi:10.20944/preprints202309.0814.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: SLC38A5; gemcitabine-resistance; PDAC; lipid ROS; ferroptosis
Online: 13 September 2023 (07:18:41 CEST)
Pancreatic cancer has a poor prognosis with its five-year survival rate lower than that of any other cancer type because it is difficult to detect in the early stages. Gemcitabine, a standard treatment for pancreatic cancer, often has poor outcomes for patients as a result of chemoresistance. Therefore, novel therapeutic targets must be identified to overcome gemcitabine-resistance. Here, we found that SLC38A5, a glutamine transporter, is more highly overexpressed in gemcitabine-resistant patients than in gemcitabine-sensitive patients. Furthermore, the deletion of SLC38A5 decreased the proliferation and migration of gemcitabine-resistant PDAC cells. We also found that the inhibition of SLC38A5 triggered the ferroptosis signaling pathway via RNA sequencing. Also, silencing SLC38A5 induced mitochondrial dysfunction and reduced glutamine uptake and glutathione (GSH) levels, and downregulated the expressions of GSH-related genes NRF2 and GPX4. The blockade of glutamine uptake negatively modulated the mTOR-SREBP1-SCD1 signaling pathway. Therefore, suppression of SLC38A5 triggers ferroptosis via two pathways that regulate lipid ROS levels. Similarly, we observed knockdown of SLC38A5 restored gemcitabine sensitivity by hindering tumor growth and metastasis in the orthotopic mouse model. Altogether, our results demonstrated that SLC38A5 could be a novel therapeutic target to overcome gemcitabine-resistance in PDAC therapy.
ARTICLE | doi:10.20944/preprints202308.0590.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: Lipid peroxidation; micronutrients; oxidative stress; photosynthetic pigments
Online: 8 August 2023 (09:27:53 CEST)
Galanthus elwesii Hook is an important plant species of the Amaryllidaceae family and is used for medicinal purposes with its valuable bioactive compounds. The present study was conducted to investigate the effects of foliar salicylic acid (SA) and zinc (Zn) treatments on proline, carotenoid, chlorophyll content and anti-oxidant enzyme activity in G. elwesii. The ascorbate peroxidase (APX), catalase (CAT) enzyme activity, and protein contents were determined with ascorbate oxidation, hydrogen peroxide (H2O2), and Bradford experiments, respectively. The plants were treated with three different concentrations of SA (0.5, 1, and 2 mM) and, and Zn (40, 80, and 120 mM) were compared with the control. Fresh leaves were harvested in the study. APX (3.99 ± 0.58 EU/mg protein) and CAT (154.64 ± 4.10 EU/mg protein) were obtained from Zn 80 and 120 mM treatments at the highest level, respectively. Proline, chlorophyll b, and carotenoid content increased 12.4, 1.54 and 3.95-fold, respectively, in 0.5 mM SA treatments when matched with control group. It was found that increasing doses of SA and Zn increased the content of malondialdehyde (MDA), but this was not at a significant level. The total chlorophyll content increased 2.27-fold in Zn 120 mM + SA 2 mM treatment and the chlorophyll content increased 2.41-fold in Zn 40 mM + SA 1 mM treatment.
ARTICLE | doi:10.20944/preprints202307.1054.v1
Subject: Medicine And Pharmacology, Pharmacy Keywords: reconstituted lipid nanoparticles; selective homing; ischemic stroke
Online: 17 July 2023 (10:46:20 CEST)
Lipid nanoparticles (LNPs) are promising carriers for constructing drug delivery systems (DDSs) in disease treatments. Previous studies have suggested that lipid composition and biophysical properties of LNPs can significantly impact their interaction with cells and tissues, allowing for the development of suitable LNPs for precise drug delivery. Our previous study proposed the concept and facile preparation of reconstituted lipid nanoparticles (rLNPs), which not only have the advantages of traditional LNPs but also contain the lipids of mother cell/tissue. In this study, we have found that brain-derived rLNPs (B-rLNPs) can have much better accumulation to the ischemic area of the ischemic stroke (IS) model than liver-derived rLNPs (L-rLNPs). This homing effect hopefully makes rLNPs a useful tool for developing highly accessible devices with homologous targeting ability for precise drug delivery.
ARTICLE | doi:10.20944/preprints202306.2126.v1
Subject: Biology And Life Sciences, Biophysics Keywords: AMP; SPR; NRM; liposomes; LPS; lipid binding
Online: 29 June 2023 (11:27:25 CEST)
Antimicrobial peptides (AMPs) are generally membrane-active compounds that physically disrupt bacterial membranes. Despite extensive research, the precise mode of action of AMPs is still a topic of great debate. This work demonstrates that the initial interaction between the Gram-negative E. coli and AMPs is driven by lipopolysaccharides (LPS) that act as kinetic barriers for the binding of AMPs to the bacterial membrane. A combination of SPR and NMR experiments provide evidence suggesting that cationic AMPs first bind to the negatively charged LPS before reaching a binding place in the lipid bilayer. In the event that the initial LPS-binding is too strong (corresponding to a low dissociation rate), the cationic AMPs cannot effectively get from the LPS to the membrane and their antimicrobial potency will thus be diminished. On the other hand, the AMPs must also be able to effectively interact with the membrane to exert its activity. The ability of the studied cyclic hexapeptides to bind LPS and to translocate into a lipid membrane is related to the nature of the cationic charge (arginine vs lysine) and to the distribution of hydrophobicity along the molecule (alternating vs clumped tryptophan).
ARTICLE | doi:10.20944/preprints202304.1103.v1
Subject: Medicine And Pharmacology, Surgery Keywords: obesity; sleeve gastrectomy; atherogenic dyslipidemia; lipid metabolism
Online: 28 April 2023 (04:17:28 CEST)
Introduction Currently, the increase in the percentage of obese people observed along with the development of civilization, reaching the level of a global pandemic, has forced the search for methods of effective and permanent obesity treatment. Obesity is a multifactorial disease, it coexists with many disease entities and requires multidisciplinary treatment. Obesity leads to metabolic changes in the form of metabolic syndrome, which includes, among others, atherogenic dyslipidemia. The proven relationship between dyslipidemia and cardiovascular risk enforces the need to effectively improve the lipid profile of obese patients. Laparoscopic sleeve gastrectomy is a method of surgical treatment of morbid obesity which improves bariatric and metabolic parameters. The aim of the study was to assess the effectiveness of laparoscopic sleeve gastrectomy (LSG) in improving lipid profile parameters in 1-year follow-up. Material and Methods Bariatric parameters of 196 patients who underwent laparoscopic sleeve gastrectomy as well as lipid profile of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), non-NDL, and triglycerides (TG) in 1-year observation were analyzed. Results Improvements in bariatric parameters were observed in patients after LSG. Total cholesterol, low-density lipoprotein (LDL), triglycerides and non-HDL levels decrease were observed along with the increase of high-density lipoprotein (HDL) cholesterol level. Conclusions Sleeve gastrectomy is an effective method of treating obesity and improving the lipid profile in obese patients.
ARTICLE | doi:10.20944/preprints202304.0439.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Adipogenesis; RBMS1; RNA-binding proteins; Lipid metabolism
Online: 17 April 2023 (10:09:50 CEST)
Adipocytes play a critical role in maintaining a healthy systemic metabolism by storing and releasing energy in the form of fat and helping to regulate glucose and lipid levels in the body. Adipogenesis is the process through which pre-adipocytes are differentiated into mature adipocytes. It is a complex process involving various transcription factors and signaling pathways. Dysregulation of adipogenesis has been implicated in the development of obesity and metabolic disorders. Therefore, understanding the mechanisms that regulate adipogenesis and the factors that contribute to its dysregulation may provide insights into the prevention and treatment of these conditions. RNA Binding Motif Single Stranded Interacting Protein 1 (RBMS1) is a protein that binds to RNA and plays a critical role in various cellular processes such as alternative splicing, mRNA stability, and translation. The RBMS1 polymorphism has been shown to be associated with obesity and Type 2 diabetes, but the role of RBMS1 in adipose metabolism and adipogenesis is not known. We show that RBMS1 is highly expressed during the early phase of differentiation of the murine adipocyte cell line 3T3-L1 and is significantly upregulated in adipose tissue depots and adipocytes of high-fat-fed mice, implying a possible role in adipogenesis and adipose metabolism. Knockdown of RBMS1 in pre-adipocytes impacted the differentiation process and reduced the expression of some of the key adipogenic markers. Transcriptomic and proteomic analysis indicated that RBMS1 depletion affected the expression of several genes involved in major metabolic processes, including carbohydrate and lipid metabolism. Our findings imply that RBMS1 plays an important role in adipocyte metabolism and may offer novel therapeutic opportunity for metabolic disorders such as obesity and type 2 diabetes.
REVIEW | doi:10.20944/preprints202107.0704.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Colicins; colicin M; peptidoglycan; lipid II; antibacterials
Online: 30 July 2021 (13:27:37 CEST)
The misuse of antibiotics during the last decades led to the emergence of multidrug resistant pathogenic bacteria. This phenomenon constitutes a major public health issue. Consequently, the discovery of new antibacterials in the short term is crucial. Colicins, due to their antibacterial properties, thus constitute good candidates. These toxin proteins, produced by E. coli to kill enteric relative competitors, exhibit cytotoxicity through ionophoric activity or essential macromolecule degradation. Among the 25-colicin types known to date, colicin M (ColM) is the only one colicin interfering with peptidoglycan biosynthesis. Accordingly, ColM develops its lethal activity in E. coli periplasm by hydrolyzing the last peptidoglycan precursor, lipid II, into two dead-end products, thereby leading to cell lysis. Since the discovery of its unusual mode of action, several ColM orthologs have also been identified based on sequence alignments; all of the characterized ColM-like proteins display the same enzymatic activity of lipid II degradation and narrow antibacterial spectra. This publication aims at being an exhaustive review about what is currently known on this new family of antibacterial enzymes as well as on their potential use of food preservatives or therapeutic agents.
ARTICLE | doi:10.20944/preprints202103.0400.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Lipid metabolism; NAFLD; genetic variants; PSRC1; HCC
Online: 15 March 2021 (16:30:15 CET)
Background and Aims: Dyslipidemia and cardiovascular diseases (CAD) are comorbidities of nonalcoholic fatty liver disease (NAFLD), which ranges from steatosis to hepatocellular carcinoma (HCC). The rs599839 A>G variant, in the CELSR2-PSRC1-SORT1 cluster, has been associated CAD, but its impact on metabolic traits and liver damage in NAFLD has not been investigated yet. Methods: We evaluated the effect of the rs599839 variant in 1426 NAFLD patients (Overall cohort) of whom 131 have HCC (NAFLD-HCC), in 500,000 individuals from the UK Biobank Cohort (UKBBC) and in 366 HCC samples from The Cancer Genome Atlas (TCGA). Hepatic PSRC1, SORT1 and CELSR2 expressions were evaluated by RNAseq (n=125). Results: The rs599839 variant was associated with reduced circulating LDL, carotid intima-media thickness, carotid plaques and hypertension (p<0.05) in NAFLD patients and with protection against dyslipidemia in UKBBC. The G allele was associated with higher risk of HCC and advanced tumor stage (p<0.05) in the Overall cohort. Hepatic PSRC1, SORT1 and CELSR2 expressions were increased in NAFLD patients carrying the rs599839 variant (p<0.0001). SORT1 mRNA levels negatively correlated with circulating lipids and with those of genes involved in lipoprotein turnover (p<0.0001). Conversely, PSRC1 expression was positively related to that of genes implicated in cell proliferation (p<0.0001). In TCGA, PSRC1 over-expression promoted more aggressive HCC development (p<0.05). Conclusions: In sum, the rs599839 A>G variant improves dyslipidemia thus protecting against CAD in NAFLD patients, but as one it might promote HCC development by modulating SORT1 and PSRC1 expressions which impact on lipid metabolism and cell proliferation, respectively
ARTICLE | doi:10.20944/preprints201810.0306.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: imperatorin; lipid microsphere; response surface methodology; pharmacokinetic
Online: 15 October 2018 (12:06:08 CEST)
Imperatorin is a chemical compound belong to Linear furan coumarins. Imperatorin is attracting considerable attention because of its anti-tumor, antibacterial, anti-inflammatory, anticoagulant and inhibition of myocardial hypetrophy and other pharmacological efficacy. However, imperatorin has limited water solubility and preferable lipid solubility, we decided to design and synthesize imperatorin lipid microsphere, to optimize preparation conditions. The aim was to develop and formulate imperatorin lipid microsphere through nano emulsion technology and apply the response surface-central composite design to optimize the imperatorin lipid microsphere formulation. Influence of content of amount of egg lecithin(A), amount of poloxamer188(B), soybean oil for injection accounted for the total percentage of oil phase(C) were investigated. Integrated effect of dependent variables including particle size(Y1), polydispersity index(Y2), Zeta potentials(Y3), drug loading(Y4), encapsulation efficiency(Y5). Data of overall desirabiities were fitted to a second-order polynomial equation, through which three dimensional response surface graphs were described. Optimum experimental conditions were calculated by Design-Expert 8.06. Results indicated that the optimum preparation conditions were as follows: egg lecithin amount 1.39 g, poloxamer188 amount 0.21 g, soybean oil for injection amount 10.57%. Preparation of imperatorin lipid microsphere according to the optimum experimental conditions resulted in an overall desirability of 0.7286, while the particele size (168±0.54) nm, polydispersity index (PDI) (0.138±0.02), Zeta potentials (−43.5±0.5) mV, drug loading (0.833±0.27) mg·mL−1, encapsulation efficiency (90±1.27)%. The difference between observed and predicted values of the overall desirability of the optimum formulation was in range from 2.4% to 4.3%. Subsequently, using the Scanning electron microscopy to observe the micromorphology of imperatorin lipid microsphere, the result shows that round globular of relatively uniform and sizes within 200nm.The proliferation study of imperatorin lipid microsphere on MDA-MB-231 was investigated by MTT method. Furthermore, pharmacokinetics in Sprague Dawley rats were evaluated using orbital bleeding. A sensitive and reliable liquid chromatography with High Performance Liquid Chromatography (HPLC) method was established and validated for the quantification of imperatorin in rat plasma samples. The data were calculated by DAS (Drug and statistics) pharmacokinetic software version3.2.6 (China). Results demonstrated that imperatorin lipid microsphere can significantly enhance the bioavailability of imperatorin and can significantly inhibit MDA-MB-231 cell proliferating. In conclusion, our results suggersted that the response surface-central composite design is suitable for the optimized lipid microspere formulation. Imperatorin Lipid microsphere can improve the bioavailability of imperatorin and inhibit the proliferation of MDA-MB-231 than that of imperatorin.
ARTICLE | doi:10.20944/preprints201611.0071.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: diabetes mellitus; metformin; glibenclamide and lipid profile
Online: 14 November 2016 (07:14:00 CET)
Diabetes mellitus (DM) has been defined as a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. This study includes (84) subjects, their age ranged from (40 to 54) years. (20) subjects were healthy chosen as control group and (64) patients with type 2 diabetes mellitus were divided into three groups according to their type of anti diabetic therapy: (23) newly diagnosed group without therapy (Group1), (20) with metformin therapy (Group2) and (21) with metformin plus glibenclamide therapies (Group3). In the study lipid profile level were quantitatively determine by enzymatic methods, in addition to that fasting plasma glucose (FPG), Glycated hemoglobin (HbA1c%) and body mass index (BMI) were identified in the patients. There is significant increase in the level of lipid profile in patients group. Metformin alone produce a non-significant favorable effect on all lipids profile parameters while metformin plus glibenclamide showed a significant reduction in TC and LDL-C.
REVIEW | doi:10.20944/preprints201904.0162.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: silymarin; silybin; nanoemulsion; solid lipid nanoparticles; nanostructured lipid carriers; liposome; polymeric particles; self-emulsifying delivery systems; enhanced bioavailability
Online: 15 April 2019 (11:23:17 CEST)
Silymarin, a mixture of flavonolignan and flavonoid polyphenolic compounds extractable from the milk thistle seed, Silybum marianum, has anti-oxidant, anti-inflammatory, anti-cancer and anti-viral activities potentially useful in the treatment of several liver disorders, such as chronic liver diseases, cirrhosis and hepatocellular carcinoma. Equally promising are the effects of silymarin in protecting the brain from the inflammatory and oxidative stress effects by which metabolic syndrome contributes to neurodegenerative diseases. However, despite clinical trials have proved that silymarin is safe at high doses (>1500 mg/day) in humans, it suffers limiting factors such as low solubility in water (<50 μg/mL), low bioavailability and poor intestinal absorption. To improve its bioavailability and provide a prolonged silymarin release at the site of absorption, the use of nanotechnological strategies appears to be a promising method to potentiate the therapeutic action and promote sustained release of the active herbal extract. The purpose of this study is to review the different nanostructured systems available in literature as delivery strategies to improve the absorption and bioavailability of silymarin.
REVIEW | doi:10.20944/preprints202311.0167.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: marine bioactive substances; hyperlipidemia; lipid metabolism; molecular mechanisms
Online: 2 November 2023 (11:07:33 CET)
Hyperlipidemia (HLP) is a metabolic disease caused by abnormal lipid metabolism. Recently, the prevalence of HLP caused by poor dietary habits in the population has been increasing yearly. In addition, the current clinical use of lipid-lowering drugs has significant ameliorating effects on lipid levels but these actions are accompanied by certain side effects. However, bioactive marine substances have been verified to have various physiological activities such as hypoglycemic, antioxidant, antithrombotic, and effects on blood pressure. Therefore, marine biological sources of hypolipidemic active substances have attracted much attention. Moreover, some of the identified active substances have been found to induce hypolipidemia by inhibiting cholesterol synthesis and absorption, or by improving the composition of intestinal microorganisms. This article introduces the sources and classification of marine-derived hypolipidemic active substances, and describes current progress in research on the main mechanism of the hypolipidemic activity of these substances.
REVIEW | doi:10.20944/preprints202310.1423.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Oxidative stress; Ferroptosis; Iron; Cell death; Lipid peroxidation
Online: 23 October 2023 (09:42:29 CEST)
Ferroptosis is a recent form of non-apoptotic cell death, which occurs due to imbalance of iron homeostasis (iron overload). Oxidative stress due to the impairment of the antioxidant system is a major pathophysiology during ferroptosis, which eventually results in lipid peroxidation. The cellular and physiological biomarker of ferroptotic cell death includes major alteration in the glutathione peroxidase 4 (GPX4) antioxidant system and lipid peroxidation induced loss of plasma membrane integrity. This review elaborates the mechanism of oxidative stress which triggers ferroptosis.
REVIEW | doi:10.20944/preprints202309.1452.v1
Subject: Medicine And Pharmacology, Pharmacy Keywords: microfluidic system; nanoparticle; lipid-based nanoparticles; polymeric nanoparticles
Online: 21 September 2023 (05:03:57 CEST)
In recent years, the field of drug delivery has seen a significant shift towards the exploration and utilisation of nanoparticles (NPs) as versatile carriers for therapeutic agents. With its ability to provide exact control over NPs' characteristics, microfluidics has emerged as a potent platform for the efficient and controlled synthesis of NPs. Microfluidic devices designed for precise fluid ma-nipulation at the micro-scale offer a unique platform for tailoring NP properties, enabling en-hanced control over NP properties such as size, morphology and size distribution while ensuring high batch-to-batch reproducibility. Microfluidics can be used to produce liposomes, solid lipid nanoparticles, polymer-based NPs and lipid-polymer hybrid NPs, as well as a variety of inorganic NPs such as silica, metal, metal oxide, quantum dots and carbon-based NPs, offering precise control over composition and surface properties. Its unique precision in tailoring NP properties holds great promise for advancing NP-based drug delivery systems in both clinical and industrial set-tings. Although challenges with large-scale production still remain, microfluidics offers a trans-formative approach to NP synthesis. In this review, starting from the historical development of microfluidic systems, the materials used to create the systems, microfabrication methods and system components will be discussed in order to provide the reader with an overview of micro-fluidic systems. In the following, studies on the fabrication of nanoparticles such as lipid NPs, polymeric NPs and inorganic NPs in microfluidic devices are included.
ARTICLE | doi:10.20944/preprints202309.1111.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: thraustochytrids; molasses; extracellular enzymes; Aurantiochytrium; lipid; fatty acids
Online: 18 September 2023 (04:48:55 CEST)
The production of oil by thraustochytrids is still costly because of its necessary and expensive culture medium. We evaluated the growth, lipid production, and fatty acid composition in an inexpensive, molasses-based (M) medium. Newly isolated thraustochytrid strains were identified as members of genus Aurantiochytrium based on 18S rRNA gene sequences. Isolated strains were repeatedly cultured in M medium for acclimatization to the medium. Acclimatized and non-acclimatized strains were cultured in basal GY medium and M medium. The lipid in the cultured cells were extracted by the Folch method, and the fatty acid composition was analyzed by gas chromatograph. The growth and lipid production in the non-acclimatized strains were significantly inhibited by culturing in M medium, whereas the growth and lipid production were improved by acclimatization treatment in the same medium. The fatty acid composition in the cultured cells were affected by the M medium compared to the basal GY medium. The production of some enzymes such as leucine and valine aryl-amidase was suppressed in the M medium, and the activities recovered by acclimatization treatment. The growth of some strains in the molasses medium was thus recovered by the acclimatization process, and the profiles of extracellular enzymes were also affected.
ARTICLE | doi:10.20944/preprints202309.0990.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: children; lipid profile; cholesterol; small for gestational age
Online: 14 September 2023 (14:05:20 CEST)
Background: Lipid disorders are one of risk factors for cardiovascular diseases. The aim of the study was to determine the lipid profile in early childhood in the group of Polish children born small for gestational age (SGA). Materials and Methods: The study included 140 children (93 SGA and 47 controls) aged 5 to 11 years. All children underwent a physical examination and blood tests for the glucose and lipid profile. SGA group was divided in subgroups: symmetrical and asymmetric intrauterine growth restriction (IUGR). Results: Blood sample analysis revealed higher levels of total cholesterol levels (SGA group 190.61 +/- 24.66 mg/dl vs control 143.23 +/- 23.90; p<0.001). The analysis of particular fractions of cholesterol showed significantly higher mean values of triglycerides, LDL-cholesterol as well as lower mean values of HDL-cholesterol in children born as SGA. Children in both groups did not differ significantly according to weight and body mass index. A statistically significantly higher glucose concentration was obtained in the group of children with IUGR with symmetrical type of IUGR. Conclusions: Children born SGA even in their early childhood, without overweight or obesity, have abnormal lipid profile, which may be a risk factor of cardiovascular diseases in adulthood.
REVIEW | doi:10.20944/preprints202308.0245.v1
Subject: Medicine And Pharmacology, Emergency Medicine Keywords: COVID-19; Lipid nanoparticles; mRNA; Vaccines; Vaccine stability
Online: 3 August 2023 (08:07:09 CEST)
Traditional vaccines are produced by using weakened or inactivated forms of disease-causing pathogens to produce the target antigen they are designed to protect against. Messenger RNA vaccines are a class of vaccines that employ a minute segment of genetic material, known as messenger RNA (mRNA), which contains directives for the cells in the body to generate a particular protein. This genetic material is synthesized in the laboratory and packaged into a lipid nanoparticle, which protects and helps it enter cells for further protein synthesis. During vaccination with mRNA vaccine, the lipid nanoparticles containing the mRNA are injected into the muscle of vaccinees. Once inside the cells, the mRNA instructs the cells to produce a protein which is then displayed on the surface of the cell, triggering an immune response. During this, the immune system recognizes the displayed protein as foreign and mounts a defense by producing antibodies and activating immune cells to target and eliminate the protein. Furthermore, these immune responses generate a memory cell, facilitating the immune system to promptly react in case of encountering the authentic pathogen as an infection in the future. The mRNA vaccines are flexible and the sequence can be easily synthesized in the lab based on the genetic information of the target pathogen. Additionally, mRNA vaccines can be developed for new strains or variants of the target disease easily. This was particularly evident during the COVID-19 pandemic, where mRNA vaccines like the Pfizer-BioNTech and Moderna vaccines were developed and authorized for emergency use within a year. But currently, available mRNA vaccines require extensive cold chain, antigen delivery, potential immune response variability optimization, and sophisticated manufacturing process. The efforts to explore next-generation mRNA vaccine development are aimed to further improve the effectiveness, stability, and delivery methods. One focus of research has been to enhance the stability of mRNA vaccines, particularly temperature sensitivity which makes storage and distribution easier, particularly in regions with limited access to cold chain infrastructure. Self-amplifying mRNA vaccines, on the other hand, are designed to generate multiple copies of the mRNA within cells which potentially leads to a higher production of the target protein, resulting in a stronger immune response. Additionally, studies are exploring new delivery systems to improve the target and efficiency of mRNA vaccines using specialized nanoparticles and liposomes to specifically deliver mRNA to certain cell types or immune cells. Another area of interest is the development of combination vaccines, where multiple mRNA sequences are included in a single vaccine protecting against multiple diseases targeting strains or variants of a particular pathogen simultaneously. While current mRNA vaccines are administered via intramuscular injection, studies are underway to deliver directly into the skin offering enhanced immune response and the ability to use smaller vaccine doses.
CASE REPORT | doi:10.20944/preprints202307.0658.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: hypertriglyceridemia; dyslipidemia; evinacumab; ANGPTL3-inhibitors; lipid-lowering drugs
Online: 11 July 2023 (10:45:58 CEST)
Evinacumab, a human monoclonal antibody against angiopoietin-like protein 3 (ANGPTL3), has recently been approved by U.S. Food and Drug Administration as an add-on therapy for homozygous familial hypercholesterolemia (HoFH) in patients of 12 years and older. Its role as a triglyceride-lowering drug is also emerging in the literature. However, it has not been approved for this indication yet, neither in the adult nor in the pediatric population. We describe the case of a 10-year-old boy who underwent an allogeneic hematopoietic stem cell transplant for acute lymphoblastic leukemia complicated by chronic graft–versus–host disease (GVHD) and presented life-threatening refractory hypertriglyceridemia due to the concomitant use of ruxolitinib and sirolimus. After the failure of the insulin treatment and due to the technical impossibility of performing lipid apheresis, we underwent the child to evinacumab treatment, obtaining a dramatic rapid reduction in triglyceride and cholesterol levels. This is the first report of a pediatric patient younger than 12 years in Europa receiving evinacumab to treat severe hypertriglyceridemia. The therapy with angiopoietin-like proteins inhibitors has been effective, safe, and well-tolerated in our patient, suggesting that evinacumab may be used in the pediatric population when other therapeutic strategies are ineffective or contraindicated.
ARTICLE | doi:10.20944/preprints202301.0316.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lipid metabolism; hass avocado; polar metabolites; phenolics; storage
Online: 18 January 2023 (03:11:29 CET)
The current study aims to investigate the changes in polar metabolites, phenolic compounds, and fatty acids in the skin of Hass avocados stored under two distinct circumstances. Fruits from the Bartolillo orchard were primarily associated with linoleic and oleic acid as significant variables. Fruits were primarily associated with palmitoleic, palmitic, and oleic acids in Quilhuica. For one orchard, the phenolic content increased at the start of storage and declined at the conclusion, whereas the opposite was true for another, showing that the outcome was depending on the orchard and storage conditions. The polar metabolites that most closely connected with the fruits of the Quilhuica orchard were serine, glutaric acid, xylitol, and D-mannitol, whereas ß-sitosterol and gluconic were related to the fruits of the Bartolillo orchard.
ARTICLE | doi:10.20944/preprints202211.0283.v1
Subject: Chemistry And Materials Science, Theoretical Chemistry Keywords: dioxins; lipid membranes; molecular dynamics; QM/MM; EDA
Online: 15 November 2022 (09:50:18 CET)
The permeation of dioxin-like pollutants, namely, chlorinated dibenzodioxins and dibenzofurans, through lipid membranes has been simulated using classic molecular dynamics (CMD) combined with the umbrella sampling approach. The most toxic forms of chlorinated dibenzodioxin and dibenzofuran, 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD) and 2,3,7,8-tetrachlorodibenzofuran (TCDF), and a dioleyl-phosphatidylcholine (DOPC) lipid membrane of 50 Å wide have been chosen for our study. The free energy profile shows the penetration process is largely favoured thermodynamically (DG≈-12 kcal/mol), with a progressively decrease of the free energy until reaching the energy minima at distances of 8Å and 9.5Å from the centre of the membrane for, respectively, TCDD and TCDF. At the centre of the membrane, both molecules display subtle local maxima with free energy differences of 0.5 and 1 kcal/mol with respect to the energy minima for TCDD and TCDF, respectively. Furthermore, the intermolecular interactions between the molecules and the lipid membrane have been characterized at the minima and the local maxima using hybrid quantum mechanics/molecular mechanics energy decomposition analysis (QM/MM-EDA). Total interaction energies of -17.5 and -16.5 kcal/mol have been found at the energy minima for TCDD and TCDF, respectively. In both cases, the dispersion forces govern the molecule-membrane interactions, no significant changes have been found at the local maxima, in agreement with the classical free energy profile. The small differences found in the results obtained for TCDD and TCDF point out the adsorption and diffusion processes through the cell membrane are not related to the different toxicity shown by these pollutants.
ARTICLE | doi:10.20944/preprints202209.0235.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: lipid homeostasis; APOE4; Alzheimer’s Disease; Aβ peptide; tau
Online: 16 September 2022 (02:57:37 CEST)
The association of the APOE4 (vs APOE3) isoform with an increased risk of Alzheimer’s Disease (AD) is unequivocal, but the underlying mechanisms remain incompletely elu-cidated. A prevailing hypothesis incriminates the impaired ability of APOE4 to clear neurotoxic amyloid-β peptides (Aβ) from the brain as the main mechanism linking apolipoprotein isoform to disease aetiology. APOE protein mediates lipid transport both within the brain and from the brain to the periphery, suggesting that lipids may be potential co-factors in APOE4-associated physiopathology. The present study reveals several alterations in pathways of lipid homeostasis in the brains of mice expressing the human APOE4 versus APOE3 isoform. Carriers of APOE4 had deficient cholesterol turnover, an imbalance in the ratio of specific classes of phospholipids, lower levels of phosphatidylethanolamines bearing poly-unsaturated fatty acids and an overall eleva-tion in levels of monounsaturated fatty acids. These modifications in lipid homeostasis were related with increased production of Aβ peptides as well as augmented levels of tau and phosphorylated tau in primary neuronal cultures. This suite of AP-OE4-associated anomalies in lipid homeostasis and neurotoxic protein levels may be related to the accrued risk for AD in APOE4 carriers and provides novel insights into potential strategies for therapeutic intervention.
ARTICLE | doi:10.20944/preprints202111.0444.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: F. thonningii; ethnomedicine; obesity; lipid profile; liver disease
Online: 24 November 2021 (08:17:39 CET)
BACKGROUND: Ficus thonningii extracts exhibit hypoglycaemic, hypolipidaemic and antioxidant activities. We investigated the potential of methanolic F. thonningii stem-bark extracts (MEFT) to protect growing Sprague-Dawley (SD) against high-fructose diet-induced metabolic derangements (MD) in a model mimicking children fed obesogenic diets. METHODS: Eighty (40 males; 40 females) 21-days old SD rat pups were randomly allocat-ed to and administered, for 8 weeks, five treatment regimens: 1 - standard rat chow (SC) + water (PW), 2 - SC + 20% (w/v) fructose solution (FS), 3 - SC + FS + fenofibrate at 100 mg/kg bwt/day, 4 - SC + FS + low dose MEFT (LD; 50 mg/kg bwt/day) and 5 - SC + FS + high dose MEFT (HD; 500 mg/kg bwt/day). Body weight, glucose load tolerance, fasting blood glucose and triglyceride, plasma insulin concentration, sensitivity to insulin, liver mass and fat content, steatosis and inflammation were determined. RESULTS: Fructose had no effect on the rats’ growth, glucose and insulin concentration, glucose tolerance and insulin sensitivity (P>0.05) but increased triglycerides in females; in-duced hepatic microsteatosis and inflammation in both sexes but macrosteatosis in females (P<0.05). In females, MEFT prevented fructose-induced plasma triglyceride increase. Low dose MEFT increased liver lipid content in females (P<0.05). The MEFT protected the rats against hepatic steatosis and inflammation but fenofibrate protected against hepatic mi-crosteatosis. CONCLUSION: MEFT can be used as prophylaxis against dietary fructose-induced ele-ments of MD but caution must be taken as low dose MEFT increases hepatic lipid accretion in females predisposing to fatty liver disease.
ARTICLE | doi:10.20944/preprints202101.0484.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: blue honeysuckle berry; polyphenols; flavonoids; lipid accumulation; lipogenesis
Online: 25 January 2021 (11:14:20 CET)
Polyphenols have been shown to possess outstanding anti-obesity properties. In this study, the effect of blue honeysuckle berry extract (BHBE) with high polyphenol content on lipid accumulation in adipocytes and the underlying mechanism were investigated for the first time. Composition analysis demonstrated that flavonoids (mainly flavonols and anthocyanins) were the primary polyphenols in BHBE, which contributed to its biological functions. The results of Oil Red O staining combined with triglyceride (TG) content determination showed that BHBE exhibited an obvious inhibitory effect on intracellular lipid accumulation in a dose-dependent manner. BHBE also reduced the protein level of fatty acid synthase (FAS) and increased the phosphorylation level of acetyl-CoA carboxylase (ACC), indicating that lipogenesis was suppressed by BHBE treatment. Moreover, BHBE was found to significantly promote the phosphorylation of AMP-activated protein kinase (AMPK) and further reduce the expression of key transcription factors (PPARγ, C/EBPα, and SREBP-1c) that regulate lipogenesis. In addition, the expression of beige adipocyte markers (Tmem26 and Cd137) and uncoupling protein 1 (UCP1) was increased in BHBE-treated adipocytes. In summary, we consider that BHBE inhibits lipid accumulation in adipocytes by suppressing lipogenesis as well as by promoting beiging of adipocytes. These results support blue honeysuckle berry as a candidate functional food against obesity.
ARTICLE | doi:10.20944/preprints201910.0270.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: apelin; galectin-3; Preeclampsia; insulin resistance; lipid profile
Online: 23 October 2019 (17:31:26 CEST)
Preeclampsia (PE) is a common pregnancy complication. It is associated with high maternal morbidity and mortality rates and intrauterine foetal growth restriction. This condition is characterised by high blood pressure and urinary protein levels. Apelin and galectin-3 (Gal- 3) are peptides involved in the regulation of body fluid homeostasis, inflammation and cardiovascular functions. This study aimed to determine the correlations amongst serum apelin and Gal-3 levels and insulin resistance (IR) in women with PE. Sixty patients with PE and 30 healthy controls participated in this study. The PE group had significantly lower apelin levels (p < 0.01) and higher Gal-3 levels (p < 0.05) than the control group. The PE group had higher serum glucose levels and β-cell functions than the control group. Moreover, patients with PE exhibited dyslipidaemia. Correlation analysis indicated that apelin and Gal-3 levels were not significantly correlated. Moreover, no correlation existed between the apelin levels and any measured parameters of the PE group. In conclusion, the elevations in serum Gal-3 levels with increments in IR-related parameters and lipid profiles reflect the possible contribution of Gal-3 to the harmful effects of IR and dyslipidemia levels on women with PE.
Subject: Chemistry And Materials Science, Biomaterials Keywords: major depressive disorder; functionalized solid lipid nanoparticles; CBR1
Online: 3 July 2019 (12:03:31 CEST)
Nanoparticles offer available tools for MDD research. In this assay, we applied CBR1 (cannabinoid receptor 1) knockout (CB1-/-) mice to study whether functionalized solid lipid nanoparticles loading with curcumin and dexanabinol (Cur/SLNs-HU-211) exhibited anti-depressant outcomes through CBR1. Wild-type (CB1+/+) animals together with CBR1 knockout (CB1-/-) animals received daily injections of Corticosterone (CORT) for 3 weeks to obtain MDD mice model, and then the therapeutic action of Cur/SLNs-HU-211 were evaluated, respectively. Our work show that Cur/SLNs-HU-211 nanoparticles in the existence of CBR1 facilitate an efficient motor function improvement in CORT-induced MDD mice model. Cur/SLNs-HU-211 nanoparticles alleviated symptoms on CB1+/+ MDD mice and resulted in dopamine and norepinephrine recovery following CORT-induced neurotoxicity. In conclusion, the possible mechanisms underlying the antidepressant effect of Cur/SLNs-HU-211 might be the induction of CB1 expression and downstream RASGEF1C and Egr1 expression, together with a significantly upregulation of neuron-specific genes in CB1+/+ mice only. In conclusion, CBR1 is necessary during the process of antidepressant activities of Cur/SLNs-HU-211 nanoparticles. This study confirms that Cur/SLNs-HU-211 nanoparticles based CBR1 in vivo targeting would be a potentially feasible and safe way to motivate future therapeutic strategies of Major Depressive Disorder.
ARTICLE | doi:10.20944/preprints201808.0136.v2
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: acute toxicity; cardiovascular depression; intravenous lipid emulsion; propofol; rat model; respiratory depression
Online: 23 October 2018 (09:34:43 CEST)
Abstract: Background and objective: Propofol is an anesthetic agent that is frequently used in anesthesia induction, maintenance and sedation. Propofol has severe side effects such as hypotension, bradycardia and respiratory depression. Although propofol is commonly used, there is no known antidote for its toxic effects. An approach to prevent toxic effects of propofol would be beneficial. The aim of this study was to assess the effects of intravenous lipid emulsion (ILE) therapy in the prevention of depressive effects of propofol on cardiovascular and respiratory systems. Materials and methods: Twenty-eight Sprague-Dawley adult rats were randomly divided into 4 groups. The saline-administered group was determined as the Control group. The second group was administered propofol (PP group); the third group was administered ILE (ILE group), and the fourth was administered propofol with ILE therapy (ILE+PP group). Systolic blood pressure (SBP), Diastolic blood pressure (DBP), Mean arterial blood pressure (MAP), Respiratory rate (RR), Heart rate (HR) and mortality were recorded at 10 points during 60 minutes. A repeated measures linear mixed-effect model with unstructured covariance was used to compare the groups. Results: In the PP group, SBP, DBP, MAP, RR and HR levels were declining steadily; all rats in this group died after 60 minutes. In the ILE+PP group, after a while, the decreased SBP, DBP, MAP, RR and HR levels increased SBP, DBP, MAP, RR and HR levels of the Propofol group were found to be significantly lower than those of the other groups (p<0.01). The mortality rate was 100% (surviving period, 60 min) for the PP group, whereas 0% for the ILE, ILE+PP and Control groups. Conclusion: Our results suggest that undesirable side effects that can be seen after propofol application such as hypotension, bradycardia and respiratory depression might be prevented by using ILE therapy.
ARTICLE | doi:10.20944/preprints201807.0399.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: flavonoids; dark chocolate; genotoxicity; lipid metabolism; glucose metabolism
Online: 22 July 2018 (11:05:27 CEST)
In recent years, Atherosclerotic Cardiovascular Disease (ACVD), Obesity and Diabetes, have increase exponentially worldwide. In the present work, we evaluate the genoprotective effect of consuming a flavonoids-rich chocolate and the improvement in the biochemical parameters related to the prevention and treatment of cardiovascular risk and metabolic syndrome in young Mexican adults. A randomized, placebo-controlled, double-blind study was undertaken in the Autonomous University of Baja California. The treatments were a daily intake of 2 grams of dark chocolate containing 70% cooca or milk chocolate. Total phenolic compounds and flavonoids were evaluated in both chocolates. Anthropometrical and Biochemical parameters were measured in the 84 participants before and after the study. Buccal epithelial genotoxicity was also evaluated from the beginning to the end of the experiment in the participants. Result suggested that flavonoids of cocoa intake have protective effects against DNA damage, and Biochemical parameters (total cholesterol, triglycerides, and LDL-cholesterol level in blood) and anthropometrical parameters (waist circumference) were also improved after six months of daily intake of 2 grams of dark chocolate with a 70% of cocoa.
REVIEW | doi:10.20944/preprints201803.0234.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: CREBH; SREBP; LXRα; PPARα; lipid metabolism; transcription; FGF21
Online: 28 March 2018 (08:06:15 CEST)
The cyclic AMP-responsive element-binding protein H (CREBH, encoded by CREB3L3) is a membrane-bound transcriptional factor that primarily localizes in the liver and small intestine. CREBH governs triglyceride metabolism in the liver, which mediates the changes in gene expression governing fatty acid oxidation, ketogenesis, and apolipoproteins upregulating LPL activity. A deficiency of CREBH in mice leads to severe hypertriglyceridemia. CREBH, in synergy with PPARα, has a crucial role in upregulating Fgf21 expression, which is implicated in metabolic homeostasis. CREBH binds to and functions as a co-activator for both PPARα and LXRα in regulating gene expression of lipid metabolism. Furthermore, intestinal CREBH in overexpression reduces cholesterol absorption and suppresses high-cholesterol diet-induced fatty liver. Conversely, a deficiency of CrebH in mice fed on various high-fat diets leads to severe fatty liver. Thus, CREBH could be a therapeutic target in the treatment of metabolic diseases.
ARTICLE | doi:10.20944/preprints201611.0094.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: diabetes mellitus; hyperglycemia; cardiomyopathy; lipid toxicity; polyphenols; aspalathin
Online: 17 November 2016 (11:19:37 CET)
Aspalathin, a C-glucosyl dihydrochalcone, has previously been shown to protect cardiomyocytes against hyperglycemia-induced shifts in substrate preference and subsequent apoptosis. However, the precise gene regulatory network remains to be elucidated. To unravel the mechanism and provide insight into this supposition, the direct effect of aspalathin in an isolated cell-based system, without the influence of any variables, was tested using an H9c2 cardiomyocytes model. Cardiomyocytes were exposed to high glucose (33 mM) for 48 hours before post-treatment with or without aspalathin. Thereafter, RNA was extracted and RT2 PCR Profiler Arrays were used to profile the expression of 336 genes. Results showed that, 57 genes were differentially regulated in the high glucose or high glucose and aspalathin treated groups. STRING analysis revealed lipid metabolism and molecular transport as the biological processes altered after high glucose treatment, followed by inflammation and apoptosis. Aspalathin was able to modulate key regulators associated with lipid metabolism (Adipoq, Apob, Cd36, Cpt1, Pparγ, Srebf1/2, Scd1 and Vldlr), insulin resistance (Igf1, Akt1, Pde3 and Map2k1), inflammation (Il3, Il6, Jak2, Lepr, Socs3, and Tnf13) and apoptosis (Bcl2 and Chuk). Collectively, our results propose that aspalathin could reverse metabolic abnormalities by activating Adipoq while modulating the expression of Pparγ and Srebf1/2, decreasing inflammation via Il6/Jak2 pathway, which together with an observed increased expression of Bcl2 prevents myocardium apoptosis.
ARTICLE | doi:10.20944/preprints202311.0878.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: efficiency, hyperlipidemia; fermented lemon juice; fermentation evaluation; lipid-lowering
Online: 14 November 2023 (08:38:41 CET)
Aging and obesity make humans more prone to cardiovascular and metabolic syndrome diseases, leading to several serious health conditions, including dyslipidemia, high blood pressure, and sleep disturbance. Hyperlipidemia means elevated blood lipid levels, including cholesterol and triglycerides. This study aimed to explore the hypolipidemic effect of fermented citrus lemon juice using a hyperlipidemic hamster model. Sugar-free lemon juice’s fermentation was optimized, and the characteristics of fresh and fermented lemon juice (FLJ) were evaluated and compared. In addition, tests were conducted to determine the appropriate hamster feed for the functional animal tests. Then, experiments were conducted to evaluate the hypolipidemic effect of the FLJ, which contained polyphenols and superoxide dismutase-like activity, on a hyperlipidemic hamster model. This study’s pre-fermentation efficiency evaluation found that 21–30 days of bacterial DMS32004 and DMS32005 fermentation of fresh lemon juice provided the best fermentation benefits. In addition, the fermentation evaluation showed that a sugar-free fermentation method provided FLJ with the best benefits. Results showed that the absorption and utilization efficiency of FLJ was higher compared with the unfermented lemon juice. After six weeks of feeding, the total cholesterol and triglyceride values in the blood and liver of the FLJ treatment groups were de-creased compared with the high-fat diet (HFD) group. In addition, the blood low-density lipoprotein cholesterol levels were significantly reduced in the FLJ treatment groups compared with the HFD group. In contrast, the blood high-density lipoprotein to low-density lipoprotein cholesterol ratio increased considerably in the FLJ treatment groups, and the total to high-density lipoprotein ratio was significantly lower than in the HFD group. Compared with the HFD group, the total cholesterol content in the FLJ treatment groups’ feces increased significantly. This study demonstrated that the sugar-free fermentation method and fermentation cycle management provided FLJ with the potential to regulate blood lipids. Further research and verification will be carried out to isolate specific substances from the FLJ and identify their mechanisms of action.
ARTICLE | doi:10.20944/preprints202310.1017.v1
Subject: Medicine And Pharmacology, Hematology Keywords: roxadustat; rhEPO; blood pressure; micro-inflammatory state; lipid metabolism
Online: 17 October 2023 (08:29:21 CEST)
Objective To observe the effect of roxadustat on blood pressure and micro-inflammatory response in patients with hemodialysis anemia, and to provide a viable technique for the treatment of hemodialysis anemia patients. Methods A total of 100 hemodialysis anemia patients admitted to the Nephrology Department of our hospital from July 2020 to July 2021 were enrolled and randomly divided into an observation group (roxadustat) and a control group (human recombinant erythropoietin (rhEPO). The clinical efficacy, blood lipid metabolism, inflammatory factor levels, iron metabolism-related indicators, blood biochemical indicators, anemia indicators, adverse reactions and blood pressure were recorded and compared. Results There was no significant difference in baseline data and serum indicators (P>0.05). The study group demonstrated superior performance to the control group in terms of clinical efficacy, blood lipid metabolism, inflammatory factor levels, iron metabolism-related indicators, blood biochemical indicators, anemia indicators, adverse reactions and blood pressure (all P<0.05). Conclusion Compared with rhEPO treatment, roxadustat exhibits a promising outcome in treating anemia and has slight impact on blood pressure of patients.
ARTICLE | doi:10.20944/preprints202309.0858.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: evolution analysis; oilseeds; regulatory system; sequence analysis; lipid signaling
Online: 13 September 2023 (10:34:20 CEST)
Phospholipases are among the important elements involved in lipid-dependent cell signaling that lead to the induction of downstream pathways. In the current study, phospholipases D (PLDs) gene family was characterized and compared in two important oilseeds crops, Brassica napus and Camelina sativa. The results revealed that PLD has 33 members in Camelina sativa (CsPLD) and 41 members in Brassica napus (BnPLD). All studied PLDs showed a negative GRAVY value, indicating that PLDs are probably hydrophilic proteins. Phylogenetic analysis separated PLDs into five subfamilies; gamma, delta, beta, alpha, and zeta. According to evolution analysis, a different evolution process was observed between CsPLD and BnPLD. In addition, the results disclosed that the most of the PLD genes have been segmentally duplicated under purifying selection. Cis-regulatory elements related to ABA and auxin responsiveness were more found in upstream region of CsPLDs, while elements linked with MeJA responsiveness were more dis-tributed in promoter region of BnPLDs. Analysis of the expression data showed that PLD alpha genes have a wide expression and are expressed in most tissues. Quantitative expression analysis (qPCR) of CsPLD genes under salt stress, 200 mM of NaCl, was done in different time series. The results revealed that the CsPLD genes are involved in the response to salinity stress and their expression levels enhance with the increase of salinity stress time. The outcomes of this research will be useful for future molecular work related to lipid signaling in oilseed plants.
ARTICLE | doi:10.20944/preprints202309.0286.v1
Subject: Biology And Life Sciences, Horticulture Keywords: essential oil; enzymatic antioxidants; drought; glutathione; lipid peroxidation; proline
Online: 6 September 2023 (04:25:57 CEST)
As abiotic stress, drought limits plant growth and minimizes productivity. The increased request for valuable essential oil extracted from geranium (Pelargonium graveolens L.) is mainly associated with plant growth, which is adversely affected by drought. Melatonin (MT) has been used to enhance plant growth under abiotic stress, however, its impact to overcome drought stress of aromatic plants including geranium is poorly investigated. In the current investigation, MT application at 100 µM was applied under 100 % (well-watered) or 50 % (drought stress) of FC to verify this role. Drought stress markedly reduced growth parameters, herb yield, and total chlorophyll; however, MT alleviated these effects. In contrast, drought enhanced the essential oil percentage in geranium leaves. Despite the reduction in oil yield caused by drought, MT application mitigated this reduction and improved both oil yield and oil components. Besides, MT treatment enhanced the accumulation of total phenols, glutathione, and proline and improved the activity of ascorbate peroxidase, catalase, and glutathione reductase with possible alleviation of drought-induced oxidative damage. Therefore, it reduced both H2O2 and malondialdehyde accumulation, and finally maintained membrane integrity. Overall, this is the first report that reveals that MT application can improve geranium resistance to drought by enhancing the antioxidant potential and protecting the cell membrane from oxidative damage.
REVIEW | doi:10.20944/preprints202308.1166.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Mesoporous materials; lipid bilayer; graphene oxide; graphene@MSN nanocomposites
Online: 16 August 2023 (20:23:59 CEST)
In the contemporary era, there has been a notable surge in the systematic utilization of therapeutic drugs that exhibit stimulus-responsive drug release patterns in specific target areas. However, challenges such as premature drug release and limited biocompatibility persist. To address these issues, the application of a lipid coating on mesoporous silica nanoparticles (MSNs) has emerged as a promising strategy. This lipid coating not only enhances the stability and biocompatibility of nanocarriers but also facilitates targeted drug delivery to diseased cells while minimizing drug release throughout the body. MSNs, renowned for their unique attributes including high porosity, morphology, and controllable pore size, have been widely recognized as suitable platforms for drug/gene delivery systems. Furthermore, graphene-based nanomaterials such as graphene oxide and reduced graphene oxide have garnered significant interest in the fields of biology and biomedicine. These materials possess exceptional characteristics such as a large surface area, distinct surface properties, high biocompatibility, and pH sensitivity, making them ideal candidates for incorporating drugs, genes, photosensitizers, and other cargo to design innovative drug delivery systems. This study aims to emphasize the ongoing efforts and advancements in enhancing the capacity and versatility of nanocomposites comprising graphene MSN composites for applications in drug delivery.
ARTICLE | doi:10.20944/preprints202308.0920.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: agaricus bisporus; chitosan; polysaccharide; lipid absorption; pancreatic lipase; obesity
Online: 11 August 2023 (09:36:31 CEST)
Agaricus bisporus is well known as a source of polysaccharides that could improve human health. The objective of this study was to explore anti-obesity effect of A. bisporus extract (H2Oslim®) abundant in polysaccharides and its underlying mechanism. Pancreatic lipase inhibitory activity in vitro was determined after treatment with H2Oslim® and chitosan. Treatment with H2Oslim® and chitosan significantly decreased pancreatic lipase activity. Five-week-old male SD rats were randomly divided into three groups for acute feeding with vehicle, H2Oslim® at 80 mg/kg body weight (BW)/day, and H2Oslim® at 160 mg/kg BW/day. H2Oslim® does-dependently increased plasma lipid clearance in an oral lipid tolerance test. Five-week-old male C57BL/6N mice were fed a control diet (CD), a high fat diet (HFD), an HFD with H2Oslim® at 80 mg/kg BW/day, H2Oslim® at 160 mg/kg BW/day, or chitosan at 160 mg/kg BW/day for eight weeks. HFD-fed mice showed significant increases of body weight, fat mass, white adipose tissue, average lipid droplet size, and serum levels of glucose, triglyceride, ALT, and AST compared to those in the CD group. However, H2Oslim® or chitosan administration ameliorated these increases. H2Oslim® or chitosan signifi-cantly reduced dietary efficiency and increased fecal excretion levels of lipid, triglyceride, and total cholesterol. These in vitro and in vivo findings suggest that H2Oslim® might act as an anti-obesity agent by inhibiting pancreatic lipase-mediated lipid absorption, at least in part.
ARTICLE | doi:10.20944/preprints202307.1446.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Lig A; Lipid A; Adjuvant; Vaccine; MPLA; Alum; Leptospirosis
Online: 20 July 2023 (15:02:37 CEST)
Leptospirosis is a zoonotic disease of global importance. The current killed vaccine provides serovar-specific protection without sterilizing immunity. Several surface antigens, including Leptospira immunoglobulin-like proteins (LigA and LigB), have been identified as subunit vaccine candidates; however, they require potent adjuvants. Bacterial Lipopolysaccharide (LPS), including lipid A, is a well-known immunostimulatory agent, and the formulation of Monophosphoryl Lipid A (MPLA) in Alum is a clinical adjuvant. Being less endotoxic, we tested the adjuvant activity of lipid A purified from L. interrogans serovar Pomona (PLA) for its ability to activate innate and enhance antigen-specific adaptive immune response. PLA-induced activation of macrophages similar to levels induced by MPLA, albeit at a much higher dose, indicating that it is less stimulatory than MPLA. Mice immunized with a Variable portion of LigA (LAV) formulated in Alum and PLA (LAV-Alum-PLA) induced significantly higher levels of LAV-specific humoral and cellular immune response than Alum but similar to levels induced by Alum-MPLA. The adjuvant activity of PLA seems to be quite similar to MPLA and primarily mediated through enhanced recruitment, activation, and uptake of antigens by innate immune cells. Moreover, like MPLA, the PLA formulation was able to generate a long-term memory response. Most importantly, PLA demonstrated better potency than MPLA formulation and generated sterilizing immunity against challenge in a hamster model of leptospirosis. Altogether, our study has provided important insight into the adjuvant activity of Leptospira lipid A and has opened avenues for the development of LPS-based vaccines against this dreadful zoonosis.
REVIEW | doi:10.20944/preprints202302.0234.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: lipid metabolism; Apicomplexa; drug discovery; calcium signaling; acidocalcisomes; parasite
Online: 14 February 2023 (04:42:12 CET)
Calcium signaling and lipid metabolism are crucial in the infection processes of Apicomplexans parasites. Thus, enzymes involved in these processes can be drug targets against Apicomplexans. For example, in malaria infection, in-depth research into lipid metabolic pathways is crucial in understanding the parasite's infection cycle, particularly during its erythrocytic infection cycle, which has been demonstrated to be a critical stage during the disease progression. Most enzymes that play critical roles in lipid synthesis and calcium signaling have been extensively studied; nonetheless, a vast knowledge gap still exists, especially on specific enzymes and their roles in the transmission and progression of the Apicomplexan parasites. Many types of infections caused by Apicomplexans are life-threatening and hard to treat. These intracellular parasites proliferate within parasitophorous vacuoles in their host cells. As the parasites multiply, they need to meet their high demand for nutrients such as amino acids and lipids. They can acquire nutrients through scavenging and biosynthesis. This review summarizes a few interesting, unique pathways in selected Apicomplexa and how such unique pathways can be targets for drugs.
REVIEW | doi:10.20944/preprints202212.0243.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: diabetes; antioxidant; antihyperglycemic; lipid profile; body weight; algal treatments
Online: 14 December 2022 (03:17:46 CET)
Currently, algae arouse a growing interest in the pharmaceutical and cosmetic area due to the fact that they have a great diversity of bioactive compounds with the potential for pharmacological, cosmetic, and nutraceutical applications. Many of these bioactive compounds are secondary metabolites whose amounts in the algae vary with varying environmental conditions. Free radicals and other active oxygen derivatives are recognized as a natural by-product of aerobic metabolism. However, reactive oxygen species directly participate in mechanisms related to various pathological states such as cancer, diabetes, atherosclerosis, Alzheimer's, and Parkinson's, among others. Diabetes mellitus (DM) is a metabolic disease resulting from changes in glucose metabolism and/or deficient production/action of insulin. This review has as its main objective to reveal the potential antioxidant and antidiabetic capacity of algae extracts.
ARTICLE | doi:10.20944/preprints202211.0069.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: reconstituted lipid nanoparticles; drug delivery systems; solvent diffusion method
Online: 3 November 2022 (03:57:32 CET)
Nanomedicine holds great potential to devise better drug delivery systems (DDSs). However, many reported nanomedicines still fall short of commercial requirements including specific targetability, scale-up manufacturing and safety. Cell/tissue based carriers, including cell membrane vehicle and exosome, are biocompatible and targeting platforms but usually suffered from low yields and unstable reproducibility. Here in this study, we proposed the concept and preparation of reconstituted lipid nanoparticles (rLNPs) to develop highly reproducible cell/tissue based lipid nanoparticles (LNPs) for drug delivery, which holds the potential as a versatile drug delivery platform. The whole lipids of cell or tissue were firstly extracted and then prepared into rLNPs using solvent diffusion method. In this way, the preparation of ultra-small (~20 nm) rLNPs can be easily applied to both cell (mouse breast cancer cell line, 4T1) and tissue (mouse liver tissue). Our results demonstrated that mouse liver tissue derived rLNPs can be further labeled/modified with imaging, targeting or other functional moieties. Furthermore, rLNPs were highly biocompatible and capable of loading different drugs including doxorubicin hydrochloride (Dox) and curcumin (Cur). Most importantly, Dox loaded rLNPs (rLNPs/Dox) showed preferable in vitro and in vivo anticancer performance. Therefore, rLNPs might be a versatile drug delivery platform for future application in the treatment of a variety of diseases.
ARTICLE | doi:10.20944/preprints202202.0149.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: immune response; fatty acid; lipid metabolism; RNA-Seq; transcriptome
Online: 10 February 2022 (10:57:03 CET)
The objective of this study was to identify key transcription factors involved in lipid metabolism and immune response related to the differentially expressed genes (DEG) from the liver samples of 35 pig model for metabolic diseases fed diets containing either 1.5 or 3.0% soybean oil (SOY1.5 or SOY3.0). A total of 281 DEG between SOY1.5 and SOY3.0 diets (log2fold-change ≥ 1 or ≤ −1; FDR-corrected p-value < 0.1) were identified, in which 129 were down-regulated and 152 were up-regulated in SOY1.5 group. The functional annotation analysis detected transcription factors linked to lipid homeostasis and immune response, such as RXRA, EGFR, and SREBP2 precursor. These findings demonstrated that key transcription factors related to lipid metabolism could be modulated by dietary inclusion of soybean oil. It could contribute to nutrigenomics research field that aims to elucidate dietary interventions in animal and human health, as well as to drive the food technology and science.
ARTICLE | doi:10.20944/preprints202109.0066.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: dyslipidemia; fetal programing; lipid metabolism; NAFLD; persistent organic pollutants
Online: 3 September 2021 (13:56:53 CEST)
Animal studies have shown that developmental exposures to polybrominated diphenyl ethers (PBDE) permanently affect blood/liver balance of lipids. No human study has evaluated associations between in utero exposures to persistent organic pollutants (POPs) and later life lipid metabolism. In this pilot, maternal plasma levels of PBDEs (BDE-47, BDE-99, BDE-100, and BDE-153) and polychlorinated biphenyls (PCB-138, PCB-153, and PCB-180) were determined at delivery in participants of GESTation and Environment (GESTE) cohort. Total cholesterol (TCh), triglycerides (TG), low and high density lipoproteins (LDL-C and HDL-C), total lipids (TL), and PBDEs were determined in serum of 147 children at ages 6-7. General linear regression was used to estimate the relationship between maternal POPs and child lipid levels with adjustment for potential confounders, and adjustment for childhood POPs. In utero BDE-99 was associated with lower childhood levels of TG (p=0.003), and non-significantly with HDL-C (p=0.06) and TL (p=0.07). Maternal PCB-138 was associated with lower childhood levels of TG (p=0.04), LDL-C (p=0.04), and TL (p=0.02). Our data indicate that in-utero exposures to POPs may be associated with long-lasting decrease in circulating lipids in children, suggesting increased lipid accumulation in the liver, a mechanism involved in NAFLD development, consistent with previously reported animal data.
ARTICLE | doi:10.20944/preprints202108.0385.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Obesity; Lactobacillus casei AP; probiotic; fermented milk; lipid profiles
Online: 18 August 2021 (14:15:22 CEST)
Obesity and hyperglycemia can trigger various diseases, including diabetes mellitus and cardiovascular ailments. Health-promoting fermented milk products can be useful in tackling these issues. One such product is the fermented milk developed using Lactobacillus casei AP, a probiotic strain from Indonesia that has not been tested in humans thus far. Our objective was to examine the effects of L. casei AP-fermented milk products on lipid profiles, blood glucose levels and monocyte chemoattractant protein-1 (MCP-1) levels in obese adults. A total of 29 obese subjects were given L. casei AP-fermented milk products, and their fasting blood glucose, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglyceride levels were measured using diagnostic system kits. MCP-1 levels were measured using enzyme-linked immunosorbent assay. It was determined that the administration of L. casei AP-fermented milk products significantly reduced total cholesterol, LDL and triglyceride levels (p < 0.05); however, it did not increase HDL (p > 0.05), MCP-1 or fasting blood glucose levels (p ≥ 0.05). In conclusion, in obese Indonesian adults, L. casei AP-fermented milk might reduce total cholesterol, LDL and triglyceride levels but may not affect HDL, MCP-1 or fasting blood glucose levels.
ARTICLE | doi:10.20944/preprints202101.0419.v1
Subject: Engineering, Automotive Engineering Keywords: Hydrolysate; Chlorella sorokiniana; lipid; biomass productivity; nutrient amended media.
Online: 21 January 2021 (12:39:53 CET)
Hydrolysate prepared from water hyacinth biomass, containing a considerable amount of solubilised carbohydrate and nutrients, was utilised as a medium for the cultivation of two strains of Chlorella sorokiniana. These strains were isolated from an oxidation pond using two different media, i.e., BG-11 and Knop's media maintained at pH-9. Different light intensities, light-dark cycles, and various concentrations of external carbon sources (monosaccharides and inorganic carbon) were used to optimise the microalgal growth. It was observed that in the presence of organic carbon (glucose), biomass productivity increased significantly (~300 mgL-1day-1) as compared to that in the presence of only inorganic carbon (~100 mgL-1day-1). For the accumulation of stress products (lipids and carbohydrates), the microalgal strains were transferred to nutrient-amended media (N-amended and P-amended). The combined effects of glucose, inorganic carbon, and a 12h:12h light-dark cycle proved to be optimum for biomass productivity. For Chlorella sp. isolated from BG-11, maximum carbohydrate content (22%) was found in the P-amended medium, whereas high lipid content (17.3%) was estimated in the N-amended medium. However, for Chlorella sp. isolated from Knop's medium, both the lipid (17%) and carbohydrate accumulation (12.3%) were found maximum in the N- amended medium. Kinetic modelling of the lipid profile revealed that kinetic coefficients obtained for strain isolated from BG-11 media were statistically significant from each other.
CONCEPT PAPER | doi:10.20944/preprints202003.0401.v1
Subject: Biology And Life Sciences, Biophysics Keywords: SNAP25; linker; protein lipid interaction; acceptor complex; exocytosis; fusion
Online: 27 March 2020 (02:56:59 CET)
A recent paper demonstrates the importance of the linker region joining the two SNARE motifs of the neuronal t-SNARE SNAP25 for maintaining rates of secretion with roles for distinct segments in speeding fusion pore expansion (Shaaban et al., 2019, Elife. 8). Remarkably, lipid perturbing agents rescue a palmitoylation-deficient phenotype that includes slow fusion pore expansion, suggesting that protein-protein interactions have a role not only in bringing together the granule or vesicle membrane with the plasma membrane but also in orchestrating protein-lipid interactions leading to the fusion reaction. Furthermore, biochemical investigations demonstrate the importance of the C-terminal domain of the linker in the formation of the plasma membrane t-SNARE acceptor complex for synaptobrevin2 (Jiang, et al., 2019, FASEB J. 33:7985-7994;Shaaban et al., 2019, Elife. 8). This insight, together with biophysical and optical studies from other laboratories (Wang, et al., 2008, Molecular Biology of the Cell. 19:3944-3955; Zhao, et al., 2013, Proc Natl Acad Sci U S A. 110:14249-14254) suggests that the plasma membrane SNARE acceptor complex between SNAP25 and syntaxin and the resulting trans SNARE complex with the v-SNARE synaptobrevin form just milliseconds before fusion.
ARTICLE | doi:10.20944/preprints202003.0368.v1
Subject: Chemistry And Materials Science, Food Chemistry Keywords: phase equilibrium; in vitro lipid digestion; fats and oils
Online: 25 March 2020 (04:14:17 CET)
The absorption of medium-chain fatty acids (MCFA) depends on the solubility of these components in the gastric fluid. Parameters such as the total MCFA concentration, carboxyl ionization level, and carbon chain length affect the solubility of these molecules. Moreover, the enzymatic lipolysis of solubilized triacylglycerol (TAG) molecules may depend on the carbon chain length of the fatty acids (FAs) components and their positions on the glycerol backbone. This present study aimed at investigating the effect of electrolyte usually formed during the gastric digestion phase on the solubility of MCFA, and evaluating the influence of the FA carbon chain length on the lipolysis rate during the in vitro digestion simulation. The results obtained here showed that the increasing of electrolyte concentrations tend to decrease the mutual solubility of systems composed by the caproic and caprylic fatty acids + sodium chloride, sodium bicarbonate, and potassium chloride solutions. We also observed that a conventional version of the thermodynamic UNIQUAC model was able to correlate the liquid-liquid phase behavior of the electrolyte solutions. Regarding the in vitro digestion simulation, the experimental data indicated that the action of the pancreatic enzyme occurred preferentially in TAG molecules comprised of short and medium-chain fatty acids.
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: heavy metals; oligodendrocytes; myelination; lipid formation; intracellular calcium regulation
Online: 1 August 2019 (04:47:18 CEST)
Evidence has been accumulated demonstrating that heavy metals may accumulate in various organs leading to tissue damage and toxic effects in mammals. In particular, the Central Nervous System (CNS) seems to be particularly vulnerable to cumulative concentrations of heavy metals, though the pathophysiological mechanisms is still to be clarified. In particular the potential role of oligodendrocyte dysfunction and myelin production after exposure to subtoxic concentration of heavy metals is to be better assessed. Here we investigated on the effect of sub-toxic concentration of several essential (Cu2 +, Cr3+, Ni2+, Co2+) and non-essential (Pb2+, Cd2+, Al3+) heavy metals on MO3.13 and SHSY5Y human oligodendrocyte and neuronal cell lines (grown individually or in co-culture). In particular, exposure of both cell lines to heavy metals produced a reduced cell viability of co-cultured cell lines compared to cells grown separately. This effect was more pronounced in neurons which were more sensitive to metals than oligodendrocytes when the cells were grown in co-culture. On the other hand, a significant reduction of lipid component in cells occurred after their exposure to heavy metals, an effect accompanied by substantial reduction of the main protein that makes up myelin (MBP) in co-cultured cells. Finally, the effect of heavy metals in oligodendrocytes were associated to imbalanced intracellular calcium ion concentration as measured through the fluorescent Rhod-2 probe, thus confirming that heavy metals, even used at subtoxic concentrations, lead to dysfunctional oligodendrocytes. In conclusion, our data show, for the first time, that sub-toxic concentrations of several heavy metals lead to dysfunctional oligodendrocytes, an effect highlighted when these cells are co-cultured with neurons. The pathophysiological mechanism(s) underlying this effect is to be better clarified. However, imbalanced intracellular calcium ion regulation, altered lipid formation and, finally, imbalanced myelin formation seem to play a major role in early stages of heavy metal-related oligodendrocyte dysfunction.
ARTICLE | doi:10.20944/preprints201809.0421.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Nanoparticles – Bio-nano interfaces – Electrostatic interactions – Supported Lipid Bilayers
Online: 20 September 2018 (16:29:35 CEST)
The impact of nanomaterials on lung fluids or on the plasma membrane of living cells has prompted researchers to examine the interactions between nanoparticles and lipid vesicles. Recent studies have shown that nanoparticle-lipid interaction leads to a broad range of structures including supported lipid bilayers (SLB), particles adsorbed at the surface or internalized inside vesicles, and mixed aggregates. Today, there is a need to have simple protocols that can readily assess the nature of structures obtained from particles and vesicles. Here we apply the method of continuous variation for measuring Job scattering plots and provide analytical expressions for the scattering intensity in various scenarios. The result that emerges from the comparison between modeling and experimental measurements is that electrostatics plays a key role in the association, but it is not sufficient to induce the formation of supported lipid bilayers.
ARTICLE | doi:10.20944/preprints201808.0026.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: AMPK; liver; lipid metabolism; fatty acid oxidation; indirect calorimetry
Online: 1 August 2018 (16:06:39 CEST)
The energy sensor AMP-activated protein kinase (AMPK) is a key player in the control of energy metabolism. AMPK regulates hepatic lipid metabolism through the phosphorylation of its well-recognized downstream target acetyl CoA carboxylase (ACC). Although AMPK activation is proposed to lower hepatic triglyceride (TG) content via the inhibition of ACC to cause inhibition of de novo lipogenesis and stimulation of fatty acid oxidation (FAO), its contribution to the inhibition of FAO in vivo has been recently questioned. We generated a mouse model of AMPK activation specifically in the liver achieved by expression of a constitutively active AMPK using adenoviral delivery. Indirect calorimetry studies revealed that liver-specific AMPK activation is sufficient to induce a reduction in the respiratory exchange ratio and an increase in FAO rates in vivo. This led to a more rapid metabolic switch from carbohydrate to lipid oxidation during the transition from fed to fasting. Finally, mice with chronic AMPK activation in the liver display high fat oxidation capacity evidenced by increased [C14]-palmitate oxidation and ketone body production leading to reduced hepatic TG content and body adiposity. Our findings suggest a role for hepatic AMPK in the remodeling of lipid metabolism between the liver and adipose tissue.
ARTICLE | doi:10.20944/preprints202309.0766.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Probiotics; pigs; growth performance; lipid profile; oxidative stress; cytokines; immunity
Online: 13 September 2023 (02:27:17 CEST)
The study investigated the effect of a multi-strain probiotic compound containing Bacillus coagulans, Enterococcus faecalis, Clostridium butyricum and Bacillus mesentericus as in-feed zinc oxide (ZnO) alterna-tive on growth performance, diarrhea incidence, antioxidant status, lipid profile, stress and immunity in weaned piglets. A total of 72 piglets were randomly divided into 3 groups with four replicates of six piglets each. The details of the groups were as follows; (i) weaned control group (WC) received basal diet, (ii) weaned probiotic group (WB) received basal diet and probiotics and (iii) positive control (PC) group received basal diet with 2500 mg/kg ZnO. The experiment lasted for 28 days. Probiotic supple-mentation improved growth performance and reduced diarrhea rate. Probiotics supplementation im-proved lipid profile; significantly lower levels of total cholesterol and low-density lipoprotein cholesterol and higher level of high-density lipoprotein cholesterol in WB group as compared to those of the control group (WC) were recorded. Probiotic supplementation stimulated antioxidant defense system by in-creasing total antioxidant capacity and decreasing lipid peroxidation. Probiotic supplementation down-regulated the stress biomarkers like serum cortisol and serum heat shock proteins. WB group showed higher serum levels of IgG and IgM throughout the study period and higher IgA at day 28 as compared to WC. These data suggest that supplementation of the probiotic minimizes the weaning stress, thereby improves the growth performance, lipid profile, antioxidant status and systemic as well as mucosal immunity. Therefore, the multi-strain probiotic compound may be used to replace ZnO in weaned piglets.
REVIEW | doi:10.20944/preprints202306.1863.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: atherosclerosis; stroke; carotid; stenosis; biomarker; plaque; lipid; inflammation; IL-6
Online: 27 June 2023 (11:00:33 CEST)
Intracranial and extracranial large artery atherosclerosis (LAA) are a main cause of ischemic stroke. Biomarkers may aid in the diagnosis of LAA and help to stratify patients´ risk of stroke. We performed a narrative review of the literature mainly published in the last five years with the aim of identifying biomarkers associated either with intracranial or extracranial LAA in humans. Several potential biomarkers of LAA mainly related to lipid pathways and inflammation have been studied. Diagnostic biomarkers of LAA were evaluated by measuring biomarkers levels in patients with LAA stroke and other stroke etiologies. Some biomarkers were associated with prognosis of LAA stroke as evaluated by the modified Rankin score. Increased levels of IL-6 and have been associated with the risk of progression of the atherosclerotic disease. Overall, in most studies, the results were not externally validated. External validation of these results is needed. In the future, biomarkers could be useful for the selection of patients for clinical trials. To adopt these biomarkers in clinical practice we will need robust multicentric studies proving their reproduci-bility and a clear practical applicability for their use.
ARTICLE | doi:10.20944/preprints202305.2011.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Freezing; protein oxidation; lipid oxidation; water-holding; GC×GC-TOFMS
Online: 29 May 2023 (12:40:14 CEST)
In order to clarify the individual role of freezing and frozen storage on the quality of fish, fillets of large-mouth bass (Micropterus salmoides) were subjected to different freezing rates (freezing with -18 °C (A), -60 °C (B), -60 °C with forced air circulation at 2 m/s (C), respectively) followed by frozen storage at -18 °C for 30 and 90 days. Another 2 groups were frozen with -60 °C, followed by storage at -40 °C (D) and -60 °C (E), respectively. Results showed that water-holding and TVBN were mainly affected by storage time. No significant changes were found in free thiol content among treatments. A greater freezing rate and lower storage temperature generally led to lower TBARS. GC×GC-TOFMS revealed a total of 66 volatile compounds which were related to lipid oxidation. PLS-DA showed that fresh samples were separated from the frozen-thawed ones, and fillets in group D & E were relatively close to fresh fillets in the composition of oxidation-related volatiles. In conclusion, freezing rate and storage temperature had significant impact on lipid oxidation and protein denaturation in the fillets of large-mouth bass, while protein oxidation was more affected by freezing rate.
REVIEW | doi:10.20944/preprints202303.0214.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: cancer; conventional therapy; combined therapy; lipid-based nanocarriers; natural compounds
Online: 13 March 2023 (04:32:05 CET)
Cancer is one of the leading causes of death, and latest predictions indicate that cancer- related deaths will increase over the next few decades. Despite significant advances in conventional therapies, treatments remain far from ideal due to limitations such as lack of selectivity, non-specific distribution, and multidrug resistance. Current research is focusing on the development of several strategies to improve the efficiency of chemotherapeutic agents and, as a result, overcome the conventional therapies challenges. In this regard, combined therapy with natural compounds and other therapeutic agents, such as chemotherapeutics or nucleic acids, has recently emerged as a new strategy for tackling the drawbacks of conventional therapies. Taking this strategy into consideration, the co-delivery of the above-mentioned agents in lipid-based nanocarriers provide some advantages by improving the potential of the therapeutic agents carried. This review encompassed different strategies associated with combined therapy, at the same time highlighting the most recent advances and outstanding advantages of lipid-based nanocarriers for achieving a promising combination therapy that may overcome cancer treatment challenges.
REVIEW | doi:10.20944/preprints202301.0183.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lung cancer; Lipid Metabolism; Glucose Metabolism; Krebs Cycle; Cholesterol Metabolism
Online: 10 January 2023 (10:39:28 CET)
Metabolic changes are an important component of tumor cell progression. Tumor cells adapt to environmental stresses via changes to carbohydrate and lipid metabolism. Autophagy, a physiological process in mammalian cells that digests damaged organelles and misfolded proteins via lysosomal degradation is closely associated with metabolism in mammalian cells acting as a meter of cellular ATP levels. In this review, we discuss the changes in glycolytic and lipid biosynthetic pathways in mammalian cells and their impact on carcinogenesis via the autophagy pathway. Also, we discuss the impact of these metabolic pathways on autophagy in lung cancer.
REVIEW | doi:10.20944/preprints202208.0248.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: action potential; soliton/wave; lipid phase transition; scientific method; membrane
Online: 15 August 2022 (04:27:26 CEST)
This article is a followup to an earlier review which outlined some of the interesting features of the soliton/wave-action potential (AP) model, and noted the need to test its key aspects; including the need to test if its presumed lipid phase transition is actually happening during AP firings in excitable cells. The intent here is to point out the sort of tests, and evidence from them, that might be needed if the soliton/wave-AP model is to be accepted broadly by biologists. Here, after an overview of the modern electrophysiological-AP model and of the soliton/wave-AP model, there are three areas considered. First, possible compositional influences on membrane properties relative to the soliton/wave-AP model are presented. Including questions with regard to the soliton/wave-AP model’s assumption that changes in surface potentials influence the transmembrane potential. Second, some recent work from the good folks who advocate for the soliton/wave-AP model concerning the occurrence of lipid phase transitions in neurons or in extracts from nervous tissues are examined. Here it is noted that there is a need to consider whether these lipid phase transitions happen within normal physiological conditions or not. Third, and finally, the advocates for the soliton/wave-AP model have adopted a thermodynamic/theory-based philosophical approach in their studies. It is argued that this philosophical approach is a radical departure from the philosophical approach used under the scientific method. The features of this new approach, and implications its use, are examined.
ARTICLE | doi:10.20944/preprints202206.0417.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: lecithin; ginger oil; essential oil; nano-lipid; drug delivery system
Online: 30 June 2022 (08:00:31 CEST)
Lipid nanoparticles have an interesting part of drug delivery system. In this study, the modification of the convention nano-lipid based soybean lecithin was demonstrated. Ginger oil derived Zingiber officinale was used along with lecithin, cholesterol and span 80 to fabricate nano-lipid (GL nano-lipid) using thin-film method. Through TEM and confocal microscope, GL nano-lipid exposes the liposome- like morphology. The average size of the resultant nanoparticles was 249.1nm with monodistribution (PDI= 0.021). The ζ-potential of GL nano-lipid was negative as similar to as prepared nano-lipid based lecithin. GL nano-lipid express the highly stable over 60 days of storage at room temperature in term of size, ζ-potential. A shift of pH value from alkaline to acid was detected in lecithin nano-lipid, while with the incorporation of ginger oil, pH value of nano-lipid dispersion was around 7.0. Furthermore, due to the rich of shogaol-6 and other active compounds in ginger oil, the GL nano-lipid is endowed with intrinsic antibacterial feature. In addition, the sulforhodamine B (SRB) assay and live/dead imaging revealed the excellent biocompatibility of GL nano-lipid. Notably, GL nano-lipid was capable to carry the hydrophobic agents as curcumin and perform a pH-dependent release profile. A subsequent characterization are a suitable potential for drug delivery system.
ARTICLE | doi:10.20944/preprints202106.0531.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Microglia; Extracellular vesicles; migration; P2X4 receptor; MFG-E8; lipid rafts
Online: 22 June 2021 (08:26:41 CEST)
Extracellular vesicles (EVs) effectively suppress neuroinflammation and induce neuroprotective effects in different disease models. However, the mechanisms by which EVs regulate neuroinflammatory response of microglia remain largely unexplored. Here, we addressed this issue by testing the action of EVs derived from human exfoliated deciduous teeth stem cells (SHEDs) on immortalized human microglial cells. We found that EVs induced a rapid increase in intracellular Ca2+ and promoted a significant ATP release in microglial after 20 min of treatment. Boyden chamber assays revealed that EVs promoted microglial migration by 20 %. Pharmacological inhibition of different subtypes of purinergic receptors demonstrated that EVs activated microglial migration preferentially through the P2X4R pathway. Proximity ligation and co-immunoprecipitation assays revealed that EVs promote association between milk fat globule-epidermal growth factor-factor VIII (MFG-E8) and P2X4 receptor proteins. Furthermore, pharmacological inhibition of αVβ3/αVβ5 integrin suppressed EV -induced cell migration and formation of lipid rafts in microglia. These results demonstrate that EVs promote microglial motility through P2X4 R/ MFG-E8 – dependent mechanisms. Our findings provide novel insights into the molecular mechanisms through which EVs target human microglia that may be exploited for the development of new therapeutic strategies targeting disease associated neuroinflammation.
ARTICLE | doi:10.20944/preprints202102.0276.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: liver receptor homolog-1; perilipin 5; triglyceride; fasting; lipid droplet
Online: 11 February 2021 (10:36:17 CET)
Liver receptor homolog-1 (LRH-1) has emerged as a regulator of hepatic glucose, bile acid, and mitochondrial metabolism. However, the functional mechanism underlying the effect of LRH-1 on lipid mobilization has not been addressed. This study investigated the regulatory function of LRH-1 in lipid metabolism during fasting. The wild-type (WT) and LRH-1 liver-specific knockout (LKO) mice were either fed or fasted for 24 h, and the liver and serum were isolated. During fasting, the LRH-1 LKO mice showed greater accumulation of triglycerides in the liver compared to that in WT mice. Interestingly, LRH-1 LKO liver decreased the perilipin 5 (PLIN5) expression and genes involved in β-oxidation. Additionally, the LRH-1 agonist dialauroylphosphatidylcholine also enhanced PLIN5 expression in human cultured HepG2 cells. To identify new target genes of LRH-1, these findings directed to analyze the PLIN5 promoter sequence, which revealed −1620/−1614 to be a putative binding site for LRH-1. This was confirmed by promoter activity and chromatin immuno-precipitation assays. Moreover, fasted WT primary hepatocytes showed increased co-localization of PLIN5 in lipid droplets (LDs) compared to that in fasted LRH-1 LKO primary hepatocytes. Overall, these findings suggest that PLIN5 might be a novel target of LRH-1 to mobilize LDs and manage the cellular needs.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Lipidomics; ssRNA+ virus; membrane fusion; lipid metabolism; cholesterol; sphingolipids; phosphatidylinositol
Online: 17 July 2020 (14:01:21 CEST)
Recent COVID-19 outbreak has come into prominence the pathogenetic mechanisms underlying the Biology and Biochemistry of viral infections. COVID-19 illness is brought about by infection with the severe acute respiratory syndrome coronavirus SARS-CoV-2 [1,2], an enveloped positive single stranded RNA virus (ssRNA+). From a lipidomics viewpoint, there is a variety of mechanisms involving virus infection that encompass virus entry, disturbance of host cell lipid metabolism, and the role played by diverse lipids in regard to the infection effectiveness. All these aspects have currently been tackled separately as independent issues and focusing on the function of proteins. Here we review the role of cholesterol and other lipids in in ssRNA+ and SARS-COV-2 infection.
ARTICLE | doi:10.20944/preprints202001.0320.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: conjugated linolenic acid; Caco-2 cell; lipid peroxidation; apoptosis; pyroptosis
Online: 27 January 2020 (02:03:33 CET)
The probiotic bacterial strain Lactobacillus plantarum ZS2058 has been proved to manifest comprehensive functions, which were due to ability to synthesise conjugated fatty acids (CFAs). To investigate the specific functions of CFAs produced by this probiotic bacterium, α-linolenic acid was isomerized by Lactobacillus plantarum strain ZS2058, and two different conjugated α-linolenic acid (CLNA) isomers were successfully isolated. These isoforms, CLNA1 (c9, t11, c15-CLNA, purity 97.48%) and CLNA2 (c9, t11, t15-CLNA, purity 99.00%), both showed the ability to inhibit the growth of three types of colon cancer cells in a time- and concentration-dependent manner. In addition, the expression of MDA in Caco-2 cells was increased by CLNA1 or CLNA2, which indicated lipid peroxidation was related to the antiproliferation activity of CLNAs. Examination of the key protein of pyroptosis showed that CLNA1 induced the cleavage of caspase-1 and gasdermin-D, while CLNA2 induced the cleavage of caspase-4, 5 and gasdermin-D. The addition of relative inhibitors could alleviate the pyroptosis by CLNAs. CLNA1 and CLNA2 showed no effect on caspase-3, 7, 9 and PARP-1, which were key proteins associated with apoptosis. And no sub-diploid apoptotic peak appeared in the result of PI single staining test. In conclusion, CLNA1 activated caspase-1 and induced Caco-2 cell pyroptosis, whereas CLNA2 induced pyroptosis through the caspase-4/5-mediated pathway. The inhibition of Caco-2 cells by the two isomers was not related to apoptosis. This is the first report showing the ability of CLNAs to activate antioxidant defenses resulting in pyroptosis.
ARTICLE | doi:10.20944/preprints201910.0193.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: antioxidant enzymes; lipid peroxidation; NaCl; Pistacia vera; rootstock; salinity stress
Online: 17 October 2019 (11:53:12 CEST)
Salinity substantially affects plant growth and crop productivity worldwide. Plants adopt several biochemical mechanisms including regulation of antioxidant biosynthesis to protect themselves against the toxic effects induced by the stress. One-year-old Pistachio rootstock exhibiting different degrees of salinity tolerance were subjected to sodium chloride induced salt stress to identify genetic diversity among cultivated pistachio rootstock for their antioxidant responses, and to determine the correlation of these enzymes to salinity stress. Leaves and roots were harvested following NaCl-induced stress. Results show that a higher concentration of NaCl treatment induced oxidative stress in the leaf tissue and to a lesser extent in the roots. Both tissues showed an increase in ascorbate peroxidase, superoxide dismutase, catalase, glutathione reductase, peroxidase and malondialdehyde. Responses of antioxidant enzymes were cultivar dependent, as well as temporal and dependent on the salinity level. Linear and quadratic regression model analysis revealed significant correlation of enzyme activities to salinity treatment in both tissues. The variation in salinity tolerance reflected their capabilities in orchestrating antioxidant enzymes at the roots and harmonized across the cell membranes of the leaves. The study provides a better understanding of root and leaf coordination in regulating the antioxidant enzymes to NaCl induced oxidative stress.
REVIEW | doi:10.20944/preprints201909.0120.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Lysophosphatidic acid; Autotaxin; inhibitor; allosteric; orthosteric; lipid chaperone; signalling, GPCR
Online: 11 September 2019 (13:18:21 CEST)
Autotaxin (ATX) is a secreted lysophospholipase D, catalysing the conversion of lysophosphatidylcholine (LPC) to bioactive lysophosphatidic acid (LPA). LPA acts through two families of G protein-coupled receptors (GPCRs) controlling key cellular responses, and is implicated in many physiological processes and pathologies. ATX has therefore been established as an important drug target in the pharmaceutical industry. Structural and biochemical studies of ATX have shown that it has a bimetallic nucleophilic catalytic site, a substrate-binding (orthosteric) hydrophobic pocket that accommodates the lipid alkyl chain, and an allosteric tunnel that can accommodate various steroids and LPA. Here we first review what is known about ATX-mediated catalysis, crucially in light of allosteric regulation. We then present the known ATX catalysis-independent functions, including binding to cell-surface integrins and proteoglycans. In light of these data we then discuss the four types of ATX inhibitors, as classified depending on their binding to the orthosteric and/or the allosteric site. Finally, we analyse the binding mode of known members of all four types and discuss how mechanistic differences might differentially modulate the activity of the ATX-LPA signalling axis, and clinical applications including cancer.
REVIEW | doi:10.20944/preprints201807.0492.v1
Subject: Physical Sciences, Biophysics Keywords: membranes; vesicles; lipids; proteins; mesophase separation; domains; lipid rafts; clusters
Online: 25 July 2018 (15:50:38 CEST)
Cell plasma membranes display a dramatically rich structural complexity characterized by functional sub-wavelength domains with specific lipid and protein composition. Under favorable experimental conditions, patterned morphologies can also be observed in vitro on model systems such as supported membranes or lipid vesicles. Lipid mixtures separating in liquid-ordered and liquid-disordered phases below a demixing temperature play a pivotal role in this context. Protein-protein and protein-lipid interactions also contribute to membrane shaping by promoting small domains or clusters. Such phase separations displaying characteristic length-scales falling in-between the nanoscopic, molecular scale on the one hand and the macroscopic scale on the other hand, are named mesophases in soft condensed matter physics. In this Review, we propose a classification of the diverse mechanisms leading to mesophase separation in biomembranes. We distinguish between mechanisms relying upon equilibrium thermodynamics and those involving out-of-equilibrium mechanisms, notably active membrane recycling. In equilibrium, we show that the mechanisms generically dwell on an up-down symmetry breaking between the upper and lower bilayer leaflets. Symmetry breaking is an ubiquitous mechanism in condensed matter physics at the heart of several important phenomena. In the present case, it can be either spontaneous (domain buckling) or explicit, i.e. due to an external cause (global or local vesicle bending properties). Whenever possible, theoretical predictions and simulation results are confronted to experiments on model systems or living cells, which enables us to identify the most realistic mechanisms from a biological perspective.
ARTICLE | doi:10.20944/preprints201706.0098.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: food composition tables; lipid profile; trans fat; fast food; spreads
Online: 20 June 2017 (11:34:57 CEST)
The lipid fraction of margarines and fast-food French-fries, two types of foods traditionally high in trans fatty acids (TFA), is assessed. TFA data reported worldwide during the last 20 years have been gathered, and show that some countries still report high TFA amounts in these products. The content of TFA was analysed in margarines (2 store and 4 premium brands) and French-fries from fast-food restaurants (5 chains). Margarines showed mean values of 0.68% and 0.43% (gTFA/100g fat) for store and premium brands, respectively. French-fries values ranged from 0.49% to 0.89%. All samples were lower than the 2% set by some European countries as the maximum legal content of TFA in fats, and contained less than 0.5g/serving, so they could also be considered “trans free products”. This work confirmed that the presence of TFA is not significant in the two analysed products and contributes to update food composition tables, key tools for epidemiological and nutrition studies.
ARTICLE | doi:10.20944/preprints202307.2088.v1
Subject: Chemistry And Materials Science, Physical Chemistry Keywords: non-steroidal anti-inflammatory drug; NSAID; lipid bilayer; EPR; 2H ESEEM
Online: 31 July 2023 (10:22:02 CEST)
Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) from the group of phenylacetic acid derivatives, which has analgesic, anti-inflammatory and antipyretic properties. The interaction of non-steroidal anti-inflammatory drugs with cell membranes can affect their physicochemical properties, which, in turn, can cause a number of side effects in the use of these drugs. Electron paramagnetic resonance (EPR) spectroscopy could be used to study the interaction of diclofenac with the membrane, if its spin-labeled analogs existed. This paper describes the synthesis of spin-labeled diclofenac (diclofenac-SL), which consists of a simple sequence of transformations such as iodination, esterification, Sonogashira cross-coupling, oxidation and saponification. EPR spectra showed that diclofenac-SL binds to in a lipid membrane composed of palmito-yl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). 2H electron spin echo spectroscopy (ESEEM) was used to determine the position of the diclofenac-SL relative to the membrane surface. It has been established that the average its depth of immersion corresponds to the 5th position of the carbon atom in the lipid chain.
ARTICLE | doi:10.20944/preprints202307.1993.v1
Subject: Biology And Life Sciences, Biophysics Keywords: mitochondria; membrane; fusion; Mifofusin; amphipathic helix; divalent cations; lipid packing defects
Online: 28 July 2023 (11:29:25 CEST)
Mitochondria are highly dynamic organelles that constantly undergo fusion and fission events to maintain their shape, distribution, and cellular function. Mitofusin 1 and 2 proteins are two dynamin-like GTPases involved in the fusion of outer mitochondrial membranes (OMM). Mitofusins are anchored to the OMM through their transmembrane domain and possess two heptad repeat domains (HR1 and HR2) in addition to their N-terminal GTPase domain. The HR1 domain was found to induce fusion via its amphipathic helix, which interacts with the lipid bilayer structure. The lipid composition of mitochondrial membranes can also impact mitochondrial fusion. However, the precise mode of action of lipids in mitochondrial fusion is not fully understood. In this study, we have examined the role of the mitochondrial lipids phosphatidylethanolamine (PE), cardiolipin (CL) and phosphatidic acid (PA) in membrane fusion induced by the HR1 domain, both in the presence and absence of divalent cations (Ca2+ or Mg2+). Our results show that PE, as well as PA in the presence of Ca2+, effectively stimulate HR1-mediated fusion, while CL has a slight inhibitory effect. By considering the biophysical properties of these lipids in the absence or presence of divalent cations, we infer that the interplay between divalent cations and specific cone-shaped lipids creates regions with packing defects in the membrane, which provides a favorable environment for the amphipathic helix of HR1 to bind to the membrane and initiate fusion.
REVIEW | doi:10.20944/preprints202307.0633.v1
Subject: Medicine And Pharmacology, Reproductive Medicine Keywords: natural products; polycystic ovarian syndrome; lipid profile; sex hormone; blood glucose
Online: 11 July 2023 (05:19:58 CEST)
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women, characterized by fluid-filled sacs in the ovaries and various symptoms including high androgen levels, endometrial irregularities, and cysts. While the cause of PCOS is unknown, it has been linked to genetic, endocrine, and metabolic factors, and there are several treatment options, including lifestyle modifications, medications, and surgery. Natural products, such as medicinal plants and fruits, are being explored as potential treatments for PCOS due to their bioactive compounds with pharmacological effects related to antioxidant, antimicrobial, anticancer, and antidiabetic properties. Some of these compounds improve insulin sensitivity, reduce inflammation, and enhance glucose metabolism, which is beneficial for women with PCOS. This review examined the effects of natural products on PCOS, including their effects on ovarian histological changes, blood glucose, sex hormones, and lipid profile, based on animal and human studies. This study suggests that the use of natural products as complementary medicine can be a promising resource for the development of effective therapeutics for PCOS, but that further research is needed to fully understand their benefits
ARTICLE | doi:10.20944/preprints202305.0018.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Diclofenac; nanoformualtion; lipid-core nanocapsules; adjuvant arthritis; stereology; cartilage; synovial membrane
Online: 1 May 2023 (04:46:33 CEST)
Introduction: Diclofenac is the most prescribed non-steroidal anti-inflammatory drug worldwide and used to reliev pain and inflammation for inflammatory arthritis. Diclofenac do not slows disease progression and cartialge damage of Rheuamtoid Arthritis individuals. Moreover, it associated with seriuos adverse effects even using regular dose regimens. Drug delivery systems can overcome this issues reducing adverse effects and optmizing efficacy. Objectives: to evaluate the activity of a lipid-core nanocapsule loaded of Diclofenac (DIC-LNC) in an experimental model of adjuvant-induced arthritis and its anti-arthritic properties at the joint components. Methods: The diclofenac nanoformulation was obtained by self-assembling methodology. The stereology analysis aproach was applied for morphological quantification of the volume, density and cellular profile count of the metatarsophalangeal joints of rats induced to adjuvant arthritis. Proinflamatory cytokines and biochemical profile was also obtained. Results: DIC-LNC is able to reduce arthitis compared to control group (p<0.0001) and DIC group (p=0.009). The TNF and IL1 cytokine as well as C-reative protein and Xanthine-oxidade were efficiently reduced by DIC-LNC. Additionally, DIC-LNC reduces synovites and condrocytes lossing compared to DIC (p<0.05)and control group (p<0.05). The synovial space volume was higher for DIC-LNC compared to DIC (p<0.05) and Control (p<0.05). These data are suggesting that DIC-LNC is showing anti-arthritic actvity preserving deep joint components. Conclusion: DIC-LNC is a promissing nanoformulation for clinical use, since is able to reduce joint inflamation and synovits, avoiding damage of cartilage and synovial space at advjuvant athrits. Further studies and developments are necessary to achieve future clinical use.
ARTICLE | doi:10.20944/preprints202203.0306.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: Atherogenesis; metabolic status; lipid index; coronary heart disease; medical check-up
Online: 23 March 2022 (03:34:35 CET)
We evaluated the usefulness of the novel cholesterol-triglyceride subgroup (CTS) indices that potentially reflect the metabolic status regarding risk of coronary heart disease (CHD) using a retrospective longitudinal study of the Japanese general population. We recruited 12,373 individuals from the annual users of our healthcare center. Among them, the first onset of CHD was recorded in 131 individuals between April, 2014 and March, 2020. The multivariate Cox proportional hazards regression analyses for all normalized lipid indices revealed that the CTSqnt index showed a comparable hazard ratio for the CHD outcome to non-high-density lipoprotein cholesterol (nonHDL-c) and triglycerides. The HR of the CTSqlt index was significantly lower than for CTSqnt, but still comparable to that for low-density lipoprotein cholesterol (LDL-c). In comparison with the other indices, CTSqlt is more sensitive to risk increment while the index value increases. Linear regression analyses for the CTS indices and previously known lipid indices suggest that the CTSqnt and CTSqlt indices reflect the quantity of atherogenic lipoproteins and size of smaller and denser LDLs, respectively. Furthermore, the CTSqnt/HDL-c index can be used as a comprehensive risk indicator that may represent the status of lipid metabolism determined by the CTSqlt and CTSqnt indices and thus may be useful for screening. The CTS indices can be used to evaluate the metabolic status of individuals, which may increase the risk of future CHD.
ARTICLE | doi:10.20944/preprints202110.0329.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: perfluoroalkyl substances (PFAS); children; adolescents; lipid profile; cholesterol; generalized additive model
Online: 22 October 2021 (12:07:37 CEST)
Background: Residents of a large area of North-Eastern Italy were exposed for decades to high concentrations of perfluoroalkyl and polyfluoroalkyl substances (PFAS) via drinking water. Despite the large amount of evidence in adults of a positive association between serum PFAS and metabolic outcomes, studies focusing on children and adolescents are limited. We evaluated the associations between serum PFAS concentrations and lipid profile, blood pressure and body mass index (BMI) in highly exposed adolescents and children. Methods: A cross-sectional analysis was conducted in 6669 adolescents (14-19 years) and 2693 children (8-11 years) enrolled in the health surveillance program of the Veneto Region. Non-fasting blood samples were obtained and analyzed for perfluorooctanoic acid (PFOA) perfluorooctane sulfonate (PFOS), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), total cholesterol (TC) high-density lipoprotein cholesterol (HDL-C) and triglycerides. Low-density lipoprotein cholesterol (LDL-C) was calculated. Systolic and diastolic blood pressure (BP) were measured and BMI z-score accounting for age and sex was estimated. The associations between ln-transformed PFAS (and categorized into quartiles) and continuous outcomes were assessed using generalized additive models. Analyses were stratified by gender and adjusted for potential confounders. Results: Among adolescents, significant associations were detected between all investigated PFAS and TC, LDL-C, and to a fewer extent HDL-C. Among children, PFOS and PFNA had significant associations with TC, LDL-C and HDL-C, while PFOA and PFHxS had significant associations with HDL-C only. Increased serum concentrations of PFAS, particularly PFOS, were associated with decreased BMI z-score. No statistically significant associations were observed between PFAS concentrations and BP. Conclusions: Our study supports a consistent association between PFAS concentration and serum lipids, stronger for PFOS and PFNA and with a greater magnitude among children compared to adolescents, and a negative association of PFAS with BMI.
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: membrane remodeling; membrane biosynthesis; membrane curvature; phospholipids; inner membrane; lipid biosynthesis
Online: 25 August 2020 (10:03:25 CEST)
Membrane remodeling and phospholipid biosynthesis are normally tightly regulated to maintain the shape and function of cells. Indeed, different physiological mechanisms ensure a precise coordination between de novo phospholipid biosynthesis and modulation of membrane morphology. Interestingly, the overproduction of certain membrane proteins hijack these regulation networks, leading to the formation of impressive intracellular membrane structures in both prokaryotic and eukaryotic cells. The proteins triggering an abnormal accumulation of membrane structures inside the cells (or membrane proliferation) share two major common features: 1) they promote the formation of highly curved membrane domains and 2) they lead to an enrichment in anionic, cone-shaped phospholipids (cardiolipin or phosphatidic acid) in the newly formed membranes. Taking into account the available examples of membrane proliferation upon protein overproduction, together with the latest biochemical, biophysical and structural data, we explore the relationship between protein synthesis and membrane biogenesis. We propose a mechanism for the formation of these non-physiological intracellular membranes that shares similarities with natural inner membrane structures found in α-proteobacteria, mitochondria and some viruses-infected cells, pointing towards a conserved feature through evolution. We hope that the information discussed in this review will give a better grasp of the biophysical mechanisms behind physiological and induced intracellular membrane proliferation, and inspire new applications, either for academia (high-yield membrane protein production and nanovesicle production) or industry (biofuel production and vaccine preparation).
ARTICLE | doi:10.20944/preprints201909.0157.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: schistosomiasis; monophosphoryl lipid A (MPLA); chemotherapy; oxidative stress; antioxidant enzymes; SEA
Online: 16 September 2019 (01:27:58 CEST)
Schistosomiasis, a crippling ailment that afflicts over 220 million people worldwide. Yet or up till now, there is no vaccine for schistosomiasis, and chemotherapy relies heavily on a single drug, the praziquantel. The present study was undertaken to investigate the therapeutic effect of Monophosphoryl Lipid A (MPLA) as an adjuvant in soluble egg antigen (SEA) vaccinated mice against the deleterious pathological impacts induced in hepatic tissues of mice by Schistosoma mansoni infection. In addition, to study the associated parasitological, immunological and biochemical parameters. Parasitological parameters showed that intraperitoneal injection of MPLA into SEA-vaccinated and S. mansoni-infected mice was effective to a significant degree in reducing the worm and egg burden, granuloma count and diameter as well as the total area of infection in their livers versus SEA-untreated but infected ones. In addition, MPLA showed ameliorative action on the elevated liver oxidative stress marker, including malondialdehyde (MDA) and decrease in the level of the antioxidant enzymes, reduced glutathione (GSH) and catalase (CAT) which may have a role in the liver damage and fibrosis due to S. mansoni infection. In conclusion, treatment with MPLA has multi-functions in attenuating the deleterious impacts of S. mansoni infection in mice livers. Its effects are mediated through a reduction of ova count, worm burden, granuloma diameter and amelioration of antioxidant defense systems, and liver function biomarkers.
ARTICLE | doi:10.20944/preprints201907.0179.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: atherogenesis; passiflora edulis sims; lipid profile; free radicals; pre-clinical trial
Online: 15 July 2019 (05:59:18 CEST)
High oxidative stress in cells due to inflammation process or excessive cell proliferation would produce oxidants or free radicals with biomarkers, one of which is malondialdehyde (MDA). Passion fruit seed’s contain high antioxidant and are expected to decrease the level of cholesterol and MDA. The objective is to identify the effect of passion fruit seed’s ethanol extract in Wistar rats that have been fed with atherogenic feed. The method was preclinical trial (post-test control group design) in rats, by administering passion fruit seed’s ethanol extract for 14 days. This study used 26 male rats aged two months, divided into 5 groups. The result showed significant difference in MDA level which was found in group that was given passion fruit seed extract 10mg/kg BW with positive control group that was given standard feed. Passion fruit seed’s extract showed significant difference in level of triglyceride, which was found in negative control group that was given atherogenic feed with group that was given passion fruit seed’s extract 5mg/kg BW (mean±standard deviation: 1.09±0.30 mg/dL vs 0.77±0.25mg/dL; p=0.048). This study showed that passion fruit seed’s ethanol extract had significant lowering effect in level of MDA, total cholesterol, and triglyceride for 14 days.
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/preprints202311.1333.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: Endocrine disruptors; Inflammation; Insulin resistance; Lipid; Adipogenesis; Microbiota; Bariatric surgery; Adipose tissue
Online: 22 November 2023 (08:25:44 CET)
Obesity affects nearly 660 million adults worldwide and is known for its many comorbidities. Although the phenomenon of obesity is not fully understood, science regularly reveals new determinants of this pathology. Among them, the persistent organic pollutants (POPs) have been recently highlighted. Mainly lipophilic, POPs are normally stored in adipose tissue and can lead to adverse metabolic effects when released into the bloodstream. The main objective of this narrative review is to discuss the different pathways by which physical activity may counteract POPs adverse effects. The research that we carried out seems to indicate that physical activity could positively influence several pathways negatively influenced by POPs, such as insulin resistance, inflammation, lipid accumulation, adipogenesis and gut microbiota dysbiosis that are associated with the development of obesity. This review also indicates how, through the controlled mobilization of POPs, physical activity could be a valuable approach to reduce the concentration of POPs in the bloodstream. These findings suggest that physical activity should be used to counteract the adverse effects of POPs. However, future studies should accurately assess its impact in specific situations such as bariatric surgery where weight loss promotes POPs blood release.
ARTICLE | doi:10.20944/preprints202309.1474.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: berries; sea buckthorn juice; lipid profile; cholesterol; inflammation markers; intervention; anthropometric characteristics.
Online: 21 September 2023 (11:31:48 CEST)
The purpose of this work was to investigate whether two-months supplementation with 100% sea buckthorn juice (SBJ) would modify blood lipids, LDL subfractions and other markers of cardiovascular risk in hypercholesterolemic women. A group of 28 hypercholesterolemic non-medicated adult women with a mean age of 50.58 ± 5.76 years consumed 50 mL of 100% SBJ daily for two-months. We observed a significant reduction of body weight (BW; p < 0.05), body mass index (BMI; p < 0.05), body fat mass (BFM; p < 0.001) and visceral fat area (VFA; p < 0.001), on the contrary, a significant increase of skeletal muscle mass (SMM; p < 0.05) and fat-free mass (FFM; p < 0.05). Supplementation with 100% SBJ significantly increased the level of high-density lipoprotein (HDL; p < 0.05), reduced the level of low-density lipoprotein (LDL; p < 0.05), atherogenic LDL subfractions (LDL3–7; p < 0.05) and improved LDL/HDL ratio (p < 0.001). After the SBJ consumption, significant reduction of C-reactive protein (CRP; p < 0.001), orosomucoid (ORM; p < 0.001) and interleukin 6 (IL-6; p < 0.05) were found. In conclusion, consumption of SBJ showed an indication of beneficial effects on cardiovascular risk factors in hypercholesterolemic women.
HYPOTHESIS | doi:10.20944/preprints202309.0196.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Neurodegenerative disorders; schizophremia; PDK1 inhibitors; Lipid replacement therapy; Aryl hydrocarbon receptor antagonists
Online: 4 September 2023 (14:29:13 CEST)
Abstract Forensic institutions throughout the country house patients with severe psychiatric illness and history of criminal violations. Improved medical care, hygiene, and nutrition led to unmatched longevity in this population which previously lived on average 15 to 20 years shorter than the public at large. On the other hand, longevity has contributed to increased prevalence of age-related diseases, including neurodegenerative disorders, which complicate clinical management. Forensic institutions, originally intended for the treatment of younger individuals, are ill-equipped for the growing number of older offenders. Moreover, as antipsychotic drugs became available in 1950s and 1960s, we are observing the first generation of forensic detainees who had aged on dopamine blockers. Although the consequences of long-term treatment with these agents are unclear, schizophrenia-associated gray matter loss, may contribute to the development of early dementia. Taken together, increased lifespan and subsequent cognitive deficit observed in long-term psychiatric institutions brought forth questions and dilemmas unencountered by the previous generations of clinicians, such as: 1. Does the presence of neurocognitive dysfunction justify antipsychotic dose reduction or discontinuation despite a lifelong history of schizophrenia and violent behavior? 2. Should neurolipidomic interventions become the standard of care in elderly individuals with lifelong schizophrenia and dementia? 3. Can patients with schizophrenia and dementia meet the Dusky standard and stand trial? 4. Should neurocognitive disorders in elderly with lifelong schizophrenia be treated differently than age-related neurodegeneration? In this article, we describe strategies for potentially slowing the development of neurocognitive disorders in forensic patients with chronic mental illness by adopting a three-prong strategy: 1. Approaching lifelong psychosis from microbial and immunological perspective. 2. Identify modifiable risk factors for age-related diseases in forensic institutions. 3. Utilizing novel receptor-independent treatments for chronic psychosis.
ARTICLE | doi:10.20944/preprints202308.0305.v1
Subject: Physical Sciences, Biophysics Keywords: ovarian cancer; lysophosphatidic acid; gelsolin; actin; lipid-protein interaction; predictive molecular modelling
Online: 3 August 2023 (10:07:10 CEST)
Lysophosphatidic acid (LPA) is a promising biomarker candidate to screen for ovarian cancer (OC) and potentially stratify and treat patients according to disease stage. LPA is known to target actin-binding protein gelsolin that is a key regulator of actin filament assembly. Previous studies have shown that the phosphate headgroup of LPA alone is inadequate to bind to the short chain of amino acids in gelsolin known as the PIP2-binding domain. Thus, the molecular-level detail of the mechanism of LPA binding is poorly understood. Here, we model LPA binding to the PIP2-binding domain of gelsolin in the gelsolin-actin complex through extensive ten microsecond atomistic molecular dynamics (MD) simulations. We predict that LPA binding causes a local conformational rearrangement due to LPA interactions with both gelsolin and actin residues. These conformational changes are a result of the amphipathic nature of LPA, where the anionic phosphate, polar glycerol and ester groups, and lipophilic aliphatic tail mediate LPA binding via charged electrostatic, hydrogen bonding, and van der Waals interactions. The negatively-charged LPA headgroup binds to the PIP2-binding domain of gelsolin-actin while its hydrophobic tail is inserted into actin, creating a strong LPA-insertion pocket that weakens the gelsolin–actin interface. The computed structure, dynamics, and energetics of the ternary gelsolin–LPA–actin complex confirms that a quantitative OC assay is possible based on LPA-triggered actin release from the gelsolin-actin complex.
ARTICLE | doi:10.20944/preprints202304.1000.v1
Subject: Public Health And Healthcare, Other Keywords: seafood processed foods; n-3 PUFA; fatty acids content; health lipid indices
Online: 26 April 2023 (15:21:50 CEST)
Seafood products are the main dietary source of n-3 polyunsaturated fatty acids (n-3 PUFA), which are essential for human health. However, due to the widespread use of processed fish products, the presence of these n-3 PUFAs may be subject to changes related to different processing methods. The aim of this study was to determine the fatty acid composition, with a focus on n-3 polyunsaturated fatty acids (n-3 PUFAs), in different processed fish and shellfish food of EU and non-EU origin purchased in supermarkets and ethnic food shops in Messina (Italy), using gas chromatography with flame-ionization detector (GC-FID). From the fatty acid profile, the atherogenic index (AI), thrombogenicity index (TI) and flesh-lipid quality index (FLQ) were determined: 0.13-1.04 (AI), 0.31-9.84 (TI) and 0.41-29.90 (FLQ). The percentages of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids had the following ranges: 13.55-50.48%, 18.91-65.58%, 13.84-52.73%, respectively. All samples showed a good presence of PUFAs and, in particular, eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) were the main n-3 polyunsaturated fatty acids (n-3 PUFA).
ARTICLE | doi:10.20944/preprints202011.0437.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Colorectal cancer; flippase; ion transporter; tumor suppressor gene; chromosome 18q; lipid transport
Online: 16 November 2020 (17:09:08 CET)
Sporadic colorectal cancer (CRC) develops through distinct molecular events. Loss of 18q chromosome is a conspicuous event in the progression of adenoma to carcinoma. There is limited information regarding the molecular effectors of this event. Earlier, we had reported ATP8B1 as a novel gene associated with CRC. ATP8B1 belongs to the family of P-type ATPases (P4 ATPase) that primarily function to facilitate the translocation of phospholipids. In this study, we attempt to implicate ATP8B1 gene located on chromosome 18q as a tumor suppressor gene. We studied indigenous patient data and confirmed the reduced expression of ATP8B1 in tumor samples. CRC cell lines were engineered with reduced and enhanced levels of ATP8B1 which provided a tool to study its role on cancer progression. Forced reduction of ATP8B1 expression either by CRISPR/Cas9 or shRNA was associated with increased growth and proliferation of CRC cell line - HT29. In contrast, overexpression of ATP8B1 resulted in reduced growth and proliferation of SW480 cell line. We generated a network of genes that are downstream of ATP8B1. Further, we provide predicted effect of modulation of ATP8B1 levels on this network and possible effect on fatty acid metabolism related genes. These results provide evidence in support of ATP8B1 being a tumor suppressor that may affect fatty acid metabolism in CRC.
ARTICLE | doi:10.20944/preprints202002.0467.v1
Subject: Biology And Life Sciences, Virology Keywords: Ebola virus; filovirus; lipid binding; Marburg virus; membrane trafficking; virus assembly; VP40
Online: 29 February 2020 (13:12:20 CET)
Marburg virus (MARV) is a lipid-enveloped negative sense single stranded RNA virus, which can cause a deadly hemorrhagic fever. MARV encodes seven proteins, including VP40 (mVP40), a matrix protein that interacts with the cytoplasmic leaflet of the host cell plasma membrane. VP40 traffics to the plasma membrane inner leaflet, where it assembles to facilitate the budding of viral particles. VP40 is a multifunctional protein that interacts with several host proteins and lipids to complete the viral replication cycle, but many of these host-interactions remain unknown or are poorly characterized. In this study, we investigated the role of a hydrophobic loop region in the carboxy-terminal domain (CTD) of mVP40 that shares sequence similarity with the CTD of Ebola virus VP40 (eVP40). These conserved hydrophobic residues in eVP40 have been previously shown to be critical to plasma membrane localization and membrane insertion. An array of cellular experiments and confirmatory in vitro work strongly suggests proper orientation and hydrophobic residues (Phe281, Leu283, and Phe286) in the mVP40 CTD are critical to plasma membrane localization. In line with the different functions proposed for eVP40 and mVP40 CTD hydrophobic residues, molecular dynamics simulations demonstrate large flexibility of residues in the EBOV CTD whereas conserved mVP40 hydrophobic residues are more restricted in their flexibility. This study sheds further light on important amino acids and structural features in mVP40 required for its plasma membrane localization as well as differences in the functional role of CTD amino acids in eVP40 and mVP40.
ARTICLE | doi:10.20944/preprints202001.0062.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: C2 domain; E3 ubiquitin ligase; lipid binding; phosphoinositide; plasma membrane; smurf1; ubiquitin
Online: 8 January 2020 (04:34:28 CET)
SMAD ubiquitination regulatory factor 1 (Smurf1) is a Nedd4 family E3 ubiquitin ligase that regulates cell motility, polarity and TGFβ signaling. Smurf1 contains an N-terminal protein kinase C conserved 2 (C2) domain that targets cell membranes and is required for interactions with membrane-localized substrates such as RhoA. Here we investigated the lipid-binding mechanism of Smurf1 C2, revealing a general affinity for anionic membranes in addition to a selective affinity for phosphoinositides (PIPs). We found that Smurf1 C2 localizes not only to the plasma membrane but also to negatively charged intracellular sites, acting as an anionic charge sensor and selective PIP-binding domain. Site-directed mutagenesis combined with docking/molecular dynamics simulations revealed that the Smurf1 C2 domain loop region primarily interacts with PIPs and cell membranes, as opposed to the β-surface cationic patch employed by other C2 domains. By depleting PIPs from the inner leaflet of the plasma membrane, we found that PIP binding is necessary for plasma membrane localization. Finally, we used a Smurf1 cellular ubiquitination assay to show that the amount of ubiquitin at the plasma membrane interface depends on the lipid-binding properties of Smurf1. This study shows the mechanism by which Smurf1 C2 targets membrane-based substrates and reveals a novel interaction based on PI(4,5)P2 and PIP3 selectivity.
ARTICLE | doi:10.20944/preprints201807.0459.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: Superparamagnetic iron oxide; Magnetic resonance imaging; Solid lipid nanoparticles; Galactose; Liver-targeted
Online: 24 July 2018 (14:01:51 CEST)
The aim of this study was to develop a novel nanostructured lipid carriers (NLCs) with hepatocytes targeting as carriers for the magnetic resonance imaging (MRI) contrast agent (i.e., magnetic nanostructured lipid carriers, MNLCs), and to evaluate the targeting ability of the MNLCs with T2-weighted MRI both in vitro and in vivo. Here, the galactose-octadecylamine (Gal-ODA) conjugates were synthesized by chemical coupling reaction between lactose acid (LA) and octadecylamine (ODA). Then the superparamagnetic iron oxide (SPIO) loaded nanostructured lipid carrier (conjugated by Gal-ODA, Gal-NLC-SPIO) was prepared by emulsification-ultrasonic method using monoglyceride as lipid materials. The Gal-NLC-SPIO with a diameter of about 50 nm could specifically internalize into LO2 (human hepatic cell line) cells. In vitro MRI results also proved the specific targeting ability of Gal-NLC-SPIO to LO2 cells. The in vivo MR imaging experiments using an orthotopic intrahepatic xenograft tumor model further validated the hepatocytes targeted effect of Gal-NLC-SPIO. The results of this study suggested that Gal-NLC-SPIO can be used as a contrast agent to aid in the diagnosis of hepatic diseases.