Advanced lipid peroxidation end products in oxidative damage to proteins. Potential role in diseases and therapeutic prospects for the inhibitors

Attenuation of Chronic Oxidative Stress-Induced Testicular and Epididymal Dysfunction by Oral Intake of Lepidium meyenii in New Zealand Rabbits

Lepidium meyenii (Maca) is a plant that has nutritional benefits and increases the effectiveness of male reproduction. In this study, oxidative stress-exposed New Zealand rabbits were used to assess the ameliorative effects of daily Maca ingestion on testicular and epididymal tissues as well as the quality of fresh and frozen/thawed sperm. Twenty-four 40-week-old, healthy New Zealand white male rabbits were divided into four groups. The first group consumed tap water and served as a control. The second group was given 300 mg of Maca daily in capsules. The third group drank water containing hydrogen peroxide (H2O2) at a concentration of 1%. Finally, the fourth group consumed H2O2 and Maca daily. The ejaculate volume, sperm concentration, vitality, motility and velocity of the H2O2 group were considerably lower than those of the other groups. Frozen/thawed spermatozoa showed more dramatic decreases in motility and velocity as a result of H2O2 consumption. The plasma concentrations of testosterone and total antioxidant capacity were also lowest in the H2O2-treated rabbits, while malondialdehyde levels were highest. Exposure to H2O2 increased collagen deposition between ST and epididymal ducts which induced testicular and epididymis fibrosis. In addition, the spermatogenic and epididymal epithelial cells exhibited signs of apoptosis, degeneration, vacuolation and a reduction in height. Maca intake attenuated most of the damaging effects of H2O2 ingestion-induced oxidative stress. Furthermore, H2O2-treated rabbits had modest nuclear androgen receptor positivity, unlike those in the Maca group. The number of Leydig cells significantly increased with daily Maca intake. In conclusion, daily intake of Maca improved reproductive performance and mitigated the damaging effects of oxidative stress on testicular and epididymal functions in New Zealand rabbits.

Long-term exposure to advanced lipid peroxidation end products impairs cognitive function through microbiota-gut-brain axis

The frequent intake of ultra-processed, heat-processed, and fat-enriched foods rich in dietary advanced lipoxidation end-products (ALEs) has been correlated with cognitive decline; however, the underlying mechanisms of action remain unexplored. This study investigated the impact of a 12-month dietary exposure to ALEs on learning, memory, and Aβ1-42 accumulation in mice, with a focus on the AMPK/SIRT1 signaling pathway and ADAM10 expression. The gut microbiota and metabolomic profiles revealed ALEs-induced gut dysbiosis and cognitive impairment, highlighting modulation through the microbiota-gut-brain axis. Key findings include increased pathogenic bacteria and decreased beneficial bacteria, linked to metabolite profile changes that affect neurotoxic Aβ1-42 peptide accumulation. This long-term comprehensive study underscores the need for dietary guidelines to reduce ALE intake and mitigate neurodegenerative disease risk, highlighting the intricate interplay between diet, gut microbiota, and cognitive health.

Role of oxidative stress in diabetes-induced complications and their management with antioxidants

Diabetes mellitus (DM) is a huge global health issue and one of the most studied diseases, with a large global prevalence. Oxidative stress is a cytotoxic consequence of the excessive development of ROS and suppression of the antioxidant defense system for ROS elimination, which accelerates the progression of diabetes complications such as diabetic neuropathy, retinopathy, and nephropathy. Hyperglycaemia induced oxidative stress causes the activation of seven major pathways implicated in the pathogenesis of diabetic complications. These pathways increase the production of ROS and RNS, which contributes to dysregulated autophagy, gene expression changes, and the development of numerous pro-inflammatory mediators which may eventually lead to diabetic complications. This review will illustrate that oxidative stress plays a vital role in the pathogenesis of diabetic complications, and the use of antioxidants will help to reduce oxidative stress and thus may alleviate diabetic complications.

Role of ferroptosis in mitochondrial damage in diabetic retinopathy

Diabetic retinopathy is driven by oxidative stress-mitochondrial damage. Activation of ROS producing cytosolic NADPH oxidase 2 (Nox2) in diabetes precedes retinal mitochondrial damage, initiating a vicious cycle of free radicals. Elevated ROS levels peroxidize membrane lipids increasing damaging lipid peroxides (LPOs). While glutathione peroxidase 4 (GPx4) neutralizes LPOs, an imbalance in its generation-neutralization leads to ferroptosis, which is characterized by increased LPOs, free iron and decreased GPx4 activity. Mitochondria are rich in polyunsaturated fatty acids and iron and have mitochondrial isoform of GPx4. Our aim was to investigate mitochondrial ferroptosis in diabetic retinopathy, focusing on Nox2 mediated ROS production. Using human retinal endothelial cells, incubated in 5 mM or 20 mM D-glucose for 12-96 h, with or without Nox2 inhibitors (100 μM apocynin, 5 μM EHop-016 or 5 μM Gp91 ds-tat), or ferroptosis inhibitors (1 μM ferrostatin-1, 50 μM deferoxamine) or activator (0.1 μM RSL3), cytosolic and mitochondrial ROS, LPOs, iron, GPx4 activity, mitochondrial integrity (membrane permeability, oxygen consumption rate, mtDNA copy numbers) and cell death were quantified. High glucose significantly increased ROS, LPOs and iron levels and inhibited GPx4 activity in cytosol, and while Nox2 and ferroptosis inhibitors prevented glucose-induced increase in ferroptosis markers, mitochondrial damage and cell death, RSL3, further worsened them. Furthermore, high glucose also increased ferroptosis markers in the mitochondria, which followed their increase in the cytosol, suggesting a role of cytosolic ROS in mitochondrial ferroptosis. Thus, targeting Nox2-ferroptosis should help break down the self-perpetuating vicious cycle of free radicals, initiated by the damaged mitochondria, and could provide novel therapeutics to prevent/retard the development of diabetic retinopathy.

Apigeninidin chloride disrupts Toxoplasma gondii Mitochondrial membrane potential and induce reactive oxygen species and metabolites production

Introduction

Apigeninidin chloride (APi) is a form of 3-deoxyanthrocyanidins (3-DAs) abundantly produced by the red Sorghum bicolor plant. It has been previously reported to be effective against Toxoplasma gondii (T. gondii) tachyzoites grown in vitro with less cytotoxic effect. However, its possible mechanism(s) of action has not been elucidated. Biochemically, we discovered that APi induced high reactive oxygen species (ROS) and mitochondria superoxide (MitoSOX) productions in tachyzoites, leading to mitochondrial membrane potential (MMP) disruption in vitro.

Methods

To confirm our biochemical results at the molecular level, we performed a liquid chromatography-mass spectrometry (LC-MS) analysis on APi-treated parasites to assess any metabolite and lipid alterations often associated with high ROS/MitoSOX production in cells.

Results

Noteworthy is that we detected several important oxidative stress-induced metabolites such as hexanal, aldehydes, methyl undeo10-enoate, butadiynyl phenyl ketone, 16-hydroxyhexadecanoic acid (16-OH, 16:0), 2-hydroxytricosanoic acid (C23:0; O), 3-oxodecanosanoic acid (C22:1; O), 2-hydroxypropylsterate, and furan fatty acids F6 (19FU-FA).

Discussion

These metabolites are associated with lipid, protein, and nucleic acid disruptions. Using atovaquone (Atov) as a control, we observed that it disrupted intracellular tachyzoites' mitochondrial membrane potential, increased ROS and MitoSOX production, and altered metabolite and lipid production similar to what was observed with our experimental compound APi. Overall, our results indicated that APi targets T. gondii tachyzoite growth through inducing oxidative stress, mitochondrial dysfunction, and eventually parasite death.

The Effect of Environmental Enrichment on Selected Physiological and Immunological Stress-Related Markers in Dairy Goats

Homeostasis preservation is essential for animal survival, and any event that causes a disturbance in homeostasis is defined as a stressor. Here, we aimed to evaluate the effect of scratch brushes and stages as an environmental enrichment to alleviate stress in dairy goats. Twenty-four mixed-breed goats were divided into two groups according to common physiological conditions in breeding farms: milking and dry (milk-producing and non-milk-producing, respectively). Ten days after exposure to environmental enrichment treatment or not (control), blood was sampled. Following the enrichment, we observed a reduction in reactive oxidative stress metabolites, advanced glycation end products (AGEs), and their binding protein (transferrin) in the dry goats, as determined by an ELISA. In contrast, no change in AGEs, along with an increase in transferrin levels, was observed in the milking goats. Moreover, oxytocin levels decreased in the dry and increased in the milking goats, while serotonin levels increased in the dry and remained unchanged in the milking goats. Additionally, gene expression of the cytokines, IL-6 and IL-1ß, and anti-oxidative proteins, lysozyme and transferrin (in peripheral blood leukocytes), as determined by qPCR, presented the same pattern: down-regulation in the dry or up-regulation in the milking goats. In conclusion, a reliable methodology was developed for measuring husbandry stress in goats and to improve dairy goats' husbandry practice. Current environmental enrichment produced different responsiveness in goats correlated to their physiological status: beneficial effect in dry goats, detrimental effect in milking goats.

Association of dietary inflammatory index and dietary oxidative balance score with gastrointestinal cancers in NHANES 2005-2018

BACKGROUND&AIMS

Gastrointestinal (GI) cancers, including gastric, liver, esophageal, pancreatic, and colorectal cancers, represent significant global health burdens. Emerging evidence suggests that dietary patterns, particularly their inflammatory and oxidative properties, may influence cancer risk. The Dietary Inflammatory Index (DII) and Dietary Oxidative Balance Score (DOBS) assess the inflammatory and oxidative effects of diets, respectively. This study aims to explore the association between DII, DOBS, and the combined risk of GI cancers, and investigates the potential mediating roles of serum albumin and red cell distribution width (RDW).

METHODS

Data from 26,320 participants in the NHANES 2005-2018 cycles were analyzed. DII was calculated based on 28 dietary components, and DOBS included 17 nutrients (3 pro-oxidants and 14 antioxidants). Logistic regression models assessed the associations between DII, DOBS, and GI cancers. Restricted cubic spline (RCS) models examined dose-response relationships. Mediation analysis evaluated the roles of serum albumin and RDW. Subgroup analyses explored interactions with demographic and health-related factors.

RESULTS

Higher DII was associated with increased GI cancer risk (OR: 1.26, 95% CI: 1.07-1.49 per unit increase), while higher DOBS was associated with reduced risk (OR: 0.90, 95% CI: 0.76-0.99 per unit increase). RCS analysis indicated a significant nonlinear relationship between DII and GI cancer risk. Serum albumin and RDW partially mediated the associations between DII, DOBS, and GI cancers. Subgroup analyses showed stronger associations for DII among certain demographics, and significant interactions were found between DII and BMI. For DOBS, significant interactions were observed with age and BMI.

CONCLUSION

This study reveals significant associations between dietary inflammatory and oxidative balance scores and GI cancer risk. Higher DII is linked to increased risk, while higher DOBS is protective. The mediating roles of serum albumin and RDW provide insights into underlying mechanisms. These findings underscore the potential of dietary modifications in GI cancer prevention and management, emphasizing the importance of anti-inflammatory and antioxidant-rich diets.

Monoamine oxidase and neurodegeneration: Mechanisms, inhibitors and natural compounds for therapeutic intervention

Mammalian flavoenzyme Monoamine oxidase (MAO) resides on the outer mitochondrial membrane (OMM) and it is involved in the metabolism of different monoamine neurotransmitters in brain. During MAO mediated oxidative deamination of relevant substrates, H2O2 is released as a catalytic by-product, thus serving as a major source of reactive oxygen species (ROS). Under normal conditions, MAO mediated ROS is reported to propel the functioning of mitochondrial electron transport chain and phasic dopamine release. However, due to its localization onto mitochondria, sudden elevation in its enzymatic activity could directly impact the form and function of the organelle. For instance, in the case of Parkinson's disease (PD) patients who are on l-dopa therapy, the enzyme could be a concurrent source of extensive ROS production in the presence of uncontrolled substrate (dopamine) availability, thus further impacting the health of surviving neurons. It is worth mentioning that the expression of the enzyme in different brain compartments increases with age. Moreover, the involvement of MAO in the progression of neurological disorders such as PD, Alzheimer's disease and depression has been extensively studied in recent times. Although the usage of available synthetic MAO inhibitors has been instrumental in managing these conditions, the associated complications have raised significant concerns lately. Natural products have served as a major source of lead molecules in modern-day drug discovery; however, there is still no FDA-approved MAO inhibitor which is derived from natural sources. In this review, we have provided a comprehensive overview of MAO and how the enzyme system is involved in the pathogenesis of different age-associated neuropathologic conditions. We further discussed the applications and drawbacks of the long-term usage of presently available synthetic MAO inhibitors. Additionally, we have highlighted the prospect and worth of natural product derived molecules in addressing MAO associated complications.

Effective-Component Compatibility of Bufei Yishen Formula III Suppresses Mitochondrial Oxidative Damage in COPD: Via Pkm2/Nrf2 Pathway

Purpose

The main objective of this study was to explore the mechanism of effective component compatibility of Bufei Yishen formula III (ECC-BYF III) in inhibiting mitochondrial oxidative stress in a rat model of chronic obstructive pulmonary disease (COPD).

Methods

A549 cells exposed to cigarette smoke extract (CSE) were used to establish a model of mitochondrial oxidative damage. The cells were treated with the plasmid encoding Pkm2 and the enzymes and proteins involved in oxidative stress and mitochondrial function were measured. A rat model of COPD was established using CS and bacteria. Two different treatments were established, ECC-BYF III (5.5 mg/kg/d) and N-acetylcysteine (54 mg/kg/day). Animals were tested for pulmonary function (Vt, PEF, FVC, FEV0.1s and Cdyn) after eight weeks of therapy and were sacrificed. Pulmonary H&E staining was performed, and the total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and malondialdehyde (MDA) content were measured. The mitochondrial function was also examined. Furthermore, the Pkm2/Nrf2 signaling pathway was evaluated.

Results

Overexpression of Pkm2 dramatically ameliorated the CS-induced mitochondrial oxidative damage. Further studies indicated that ECC-BYF III significantly improved mitochondrial function and inhibited oxidative stress in the lung tissues of COPD rats. Moreover, it can upregulate mitochondrial respiratory chain enzyme activity. ECC-BYF III also decreased the MDA content and increased T-SOD, GSH-Px, and T-AOC expression to facilitate oxidative homeostasis. Finally, our results indicated that the Pkm2/Nrf2 pathway is regulated by ECC-BYF III in A549 cells and lung tissue.

Conclusion

These results indicate that ECC-BYF III exerts a strong effective therapeutic effect against cigarette smoke combined with bacteria-induced COPD in rats by activating the Pkm2/Nrf2 signaling pathway and restoring mitochondrial oxidative stress. Although more in vivo animal model research is needed to confirm these findings, this study contributes new data to support the conventional usage of ECC-BYF III.

Elucidating the effect of levothyroxine and triiodothyronine on methylglyoxal derived stress

PURPOSE

Methylglyoxal (MG) is the most potent precursor during the formation of the advanced glycation end products (AGEs). MG-dependent glycative stress contributes to pathogenesis of diabetes, age-related disorders, and cancer. There is a great need to study the reduction process of glycative stress for effective management of metabolic disorders. From natural compounds to synthetic drugs, each element contributes to the reduction of glycative stress. Previously, it was established that the lowering of uric acid, low-density lipoprotein cholesterol, and urine albumin excretion rate, as well as reducing total oxidative stress, were all achieved more effectively with a levothyroxine regimen. Still, there is no such study found that supports the MG-dependent glycative stress reduction with thyroid hormone compound. Our study aims to investigate the effects of T3 and T4 on MG-dependent glycative stress.

METHODS

The antiglycation effect was assayed through NBT assay, DNPH assay, ELISA, and fluorescence spectrophotometer. The intracellular reduction in reactive oxygen species (ROS) has been estimated through confocal microscopy.

RESULTS

The results revealed an effective reduction in the formation of AGEs adducts and intracellular ROS formation.

CONCLUSION

The investigation concludes AGEs formation was suppressed using these compounds, although in vivo and rigorous clinical trials are required in order to verify these findings.

Protein Haptenation and Its Role in Allergy

Humans are exposed to numerous electrophilic chemicals either as medicines, in the workplace, in nature, or through use of many common cosmetic and household products. Covalent modification of human proteins by such chemicals, or protein haptenation, is a common occurrence in cells and may result in generation of antigenic species, leading to development of hypersensitivity reactions. Ranging in severity of symptoms from local cutaneous reactions and rhinitis to potentially life-threatening anaphylaxis and severe hypersensitivity reactions such as Stephen-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), all these reactions have the same Molecular Initiating Event (MIE), i.e. haptenation. However, not all individuals who are exposed to electrophilic chemicals develop symptoms of hypersensitivity. In the present review, we examine common chemistry behind the haptenation reactions leading to formation of neoantigens. We explore simple reactions involving single molecule additions to a nucleophilic side chain of proteins and complex reactions involving multiple electrophilic centers on a single molecule or involving more than one electrophilic molecule as well as the generation of reactive molecules from the interaction with cellular detoxification mechanisms. Besides generation of antigenic species and enabling activation of the immune system, we explore additional events which result directly from the presence of electrophilic chemicals in cells, including activation of key defense mechanisms and immediate consequences of those reactions, and explore their potential effects. We discuss the factors that work in concert with haptenation leading to the development of hypersensitivity reactions and those that may act to prevent it from developing. We also review the potential harnessing of the specificity of haptenation in the design of potent covalent therapeutic inhibitors.

Molecular dynamics of structural effects of reactive carbonyl species derivate of lipid peroxidation on bovine serum albumin

BACKGROUND

Serum albumin is the most abundant protein in the Mammalia blood plasma at where plays a decisive role in the transport wide variety of hydrophobic ligands. BSA undergoes oxidative modifications like the carbonylation by the reactive carbonyl species (RCSs) 4-hydroxy-2-nonenal (HNE), 4 hydroxy-2-hexenal (HHE), malondialdehyde (MDA) and 4-oxo-2-nonenal (ONE), among others. The structural and functional changes induced by protein carbonylation have been associated with the advancement of neurodegenerative, cardiovascular, metabolic and cancer diseases.

METHODS

To elucidate structural effects of protein carbonylation with RCSs on BSA, parameters for six new non-standard amino acids were designated and molecular dynamics simulations of its mono‑carbonylated-BSA systems were conducted in the AMBER force field. Trajectories were evaluated by RMSD, RMSF, PCA, RoG and SASA analysis.

RESULTS

An increase in the conformational instability for all proteins modified with local changes were observed, without significant changes on the BSA global three-dimensional folding. A more relaxed compaction level and major solvent accessible surface area for modified systems was found. Four regions of high molecular fluctuation were identified in all modified systems, being the subdomains IA and IIIB those with the most remarkable local conformational changes. Regarding essential modes of domain movements, it was evidenced that the most representatives were those related to IA subdomain, while IIIB subdomain presented discrete changes.

CONCLUSIONS

RCSs induces local structural changes on mono‑carbonylated BSA. Also, this study extends our knowledge on how carbonylation by RCSs induce structural effects on proteins.

Lipid Oxidation Products and the Risk of Cardiovascular Diseases: Role of Lipoprotein Transport

Cholesterol has for decades ruled the history of atherosclerotic cardiovascular diseases (CVDs), and the present view of the etiology of the disease is based on the transport of cholesterol by plasma lipoproteins. The new knowledge of the lipoprotein-specific transport of lipid oxidation products (LOPs) has introduced another direction to the research of CVD, revealing strong associations between lipoprotein transport functions, atherogenic LOP, and CVD. The aim of this review is to present the evidence of the lipoprotein-specific transport of LOP and to evaluate the potential consequences of the proposed role of the LOP transport as a risk factor. The associations of cholesterol and lipoprotein LOP with the known risk factors of CVD are mostly parallel, and because of the common transport and cellular intake mechanisms it is difficult to ascertain the independent effects of either cholesterol or LOP. While cholesterol is known to have important physiological functions, LOPs are merely regarded as metabolic residues and able to initiate and boost atherogenic processes. It is therefore likely that with the increased knowledge of the lipoprotein-specific transport of LOP, the role of cholesterol as a risk factor of CVD will be challenged.

Effect of advanced glycation end-products in a wide range of medical problems including COVID-19

Glycation is a physiological process that determines the aging of the organism, while in states of metabolic disorders it is significantly intensified. High concentrations of compounds such as reducing sugars or reactive aldehydes derived from lipid oxidation, occurring for example in diabetes, atherosclerosis, dyslipidemia, obesity or metabolic syndrome, lead to increased glycation of proteins, lipids and nucleic acids. The level of advanced glycation end-products (AGEs) in the body depends on rapidity of their production and the rate of their removal by the urinary system. AGEs, accumulated in the extracellular matrix of the blood vessels and other organs, cause irreversible changes in the biochemical and biomechanical properties of tissues. As a consequence, micro- and macroangiopathies appear in the system, and may contribute to the organ failure, like kidneys and heart. Elevated levels of AGEs also increase the risk of Alzheimer's disease and various cancers. In this paper, we propose a new classification due to modified amino acid residues: arginyl-AGEs, monolysyl-AGEs and lysyl-arginyl-AGEs and dilysyl-AGEs. Furthermore, we describe in detail the effect of AGEs on the pathogenesis of metabolic and old age diseases, such as diabetic complications, atherosclerosis and neurodegenerative diseases. We summarize the currently available data on the diagnostic value of AGEs and present the AGEs as a therapeutic goal in a wide range of medical problems, including SARS-CoV-2 infection and so-called long COVID.

Reactive Carbonyl Species and Protein Lipoxidation in Atherogenesis

Atherosclerosis is a multifactorial disease of medium and large arteries, characterized by the presence of lipid-rich plaques lining the intima over time. It is the main cause of cardiovascular diseases and death worldwide. Redox imbalance and lipid peroxidation could play key roles in atherosclerosis by promoting a bundle of responses, including endothelial activation, inflammation, and foam cell formation. The oxidation of polyunsaturated fatty acids generates various lipid oxidation products such as reactive carbonyl species (RCS), including 4-hydroxy alkenals, malondialdehyde, and acrolein. RCS covalently bind to nucleophilic groups of nucleic acids, phospholipids, and proteins, modifying their structure and activity and leading to their progressive dysfunction. Protein lipoxidation is the non-enzymatic post-translational modification of proteins by RCS. Low-density lipoprotein (LDL) oxidation and apolipoprotein B (apoB) modification by RCS play a major role in foam cell formation. Moreover, oxidized LDLs are a source of RCS, which form adducts on a huge number of proteins, depending on oxidative stress intensity, the nature of targets, and the availability of detoxifying systems. Many systems are affected by lipoxidation, including extracellular matrix components, membranes, cytoplasmic and cytoskeletal proteins, transcription factors, and other components. The mechanisms involved in lipoxidation-induced vascular dysfunction are not fully elucidated. In this review, we focus on protein lipoxidation during atherogenesis.

The skin sensitization adverse outcome pathway: exploring the role of mechanistic understanding for higher tier risk assessment

For over a decade, the skin sensitization Adverse Outcome Pathway (AOP) has served as a useful framework for development of novel in chemico and in vitro assays for use in skin sensitization hazard and risk assessment. Since its establishment, the AOP framework further fueled the existing efforts in new assay development and stimulated a plethora of activities with particular focus on validation, reproducibility and interpretation of individual assays and combination of assay outputs for use in hazard/risk assessment. In parallel, research efforts have also accelerated in pace, providing new molecular and dynamic insight into key events leading to sensitization. In light of novel hypotheses emerging from over a decade of focused research effort, mechanistic evidence relating to the key events in the skin sensitization AOP may complement the tools currently used in risk assessment. We reviewed the recent advances unraveling the complexity of molecular events in sensitization and signpost the most promising avenues for further exploration and development of useful assays.

Lipid droplets, autophagy, and ageing: A cell-specific tale

Lipid droplets are the essential organelle for storing lipids in a cell. Within the variety of the human body, different cells store, utilize and release lipids in different ways, depending on their intrinsic function. However, these differences are not well characterized and, especially in the context of ageing, represent a key factor for cardiometabolic diseases. Whole body lipid homeostasis is a central interest in the field of cardiometabolic diseases. In this review we characterize lipid droplets and their utilization via autophagy and describe their diverse fate in three cells types central in cardiometabolic dysfunctions: adipocytes, hepatocytes, and macrophages.

Extraction, purification, structural characteristics and biological properties of the polysaccharides from Armillaria mellea (Vahl) P. Kumm.: A review

Armillaria mellea (Vahl) P. Kumm. is a well-known homoeopathic plant with medicinal and culinary uses. Modern phytochemical researchers have successfully extracted and purified over 40 types of A. mellea polysaccharides (AMPs) from the fruiting bodies, hyphae and fermentation broth of A. mellea, and some of them have been analyzed and identified by their chemical structures. The impressive biological activity of these polysaccharides has been recognized by scientists worldwide. Many studies show that AMPs have remarkable antioxidant, anti-diabetic, anti-tumor, anti-inflammatory, immunoregulatory, hypolipidemic, thrombectomy, anti-aging, pulmonary protective, hepatic protective, anti-Alzheimer's properties, etc. However, the current understanding of the relationships between their chemical structure and biological activity, toxicological effects and pharmacokinetics remains limited. This article provides a systematic review of the research conducted over the past decades on the extraction and purification methods, structural characteristics, biological activity and mechanism of action of AMPs. The aim is to provide a research base that will benefit the future application of AMPs as therapeutic drugs and functional foods, and also provide insights for the further development of AMPs.

Plantago asiatica L. polysaccharides: Physiochemical properties, structural characteristics, biological activity and application prospects: A review

Plantago asiatica L. (PAL), a traditional herb, has been used in East Asia for thousands of years. In recent years, polysaccharides extracted from PAL have garnered increased attention due to their outstanding pharmacological and biological properties. Previous research has established that PAL-derived polysaccharides exhibit antioxidant, anti-inflammatory, antidiabetic, antitumor, antimicrobial, immune-regulatory, intestinal health-promoting, antiviral, and other effects. Nevertheless, a comprehensive summary of the research related to Plantago asiatica L. polysaccharides (PALP) has not been reported to date. In this paper, we review the methods for isolation and purification, physiochemical properties, structural features, and biological activities of PALP. To provide a foundation for research and application in the fields of medicine and food, this review also outlines the future development prospects of plantain polysaccharides.

Brazilin-7-acetate, a novel potential drug of Parkinson's disease, hinders the formation of α-synuclein fibril, mitigates cytotoxicity, and decreases oxidative stress

Parkinson's disease (PD) is a prevalent neurodegenerative disorder characterized by the accumulation of α-synuclein (α-Syn) aggregates. However, there are currently no effective therapies for PD. Brazilin, an inhibitor of α-Syn aggregation, is unstable and toxic. Therefore, we have developed and synthesized derivatives of brazilin. One of these derivatives, called brazilin-7-acetate (B-7-A), has shown reduced toxicity and a stronger effect on inhibiting α-Syn aggregation. It showed that B-7-A prevented the formation of α-Syn fibers and disrupted existing fibers in a dosage-dependent manner. Additionally, B-7-A significantly reduced the cytotoxicity of α-Syn aggregates and alleviated oxidative stress in PC12 cells. The beneficial effects of B-7-A were also confirmed using the Caenorhabditis elegans model. These effects included preventing the accumulation of α-Syn clumps, improving behavior disorder, increasing lifespan, reducing oxidative stress, and protecting against lipid oxidation and loss. Finally, B-7-A showed good ADMET properties in silico. Based on these findings, B-7-A exhibits potential as a prospective treatment for PD.

Iron scavenging and suppression of collagen cross-linking underlie antifibrotic effects of carnosine in the heart with obesity

Oral consumption of histidyl dipeptides such as l-carnosine has been suggested to promote cardiometabolic health, although therapeutic mechanisms remain incompletely understood. We recently reported that oral consumption of a carnosine analog suppressed markers of fibrosis in liver of obese mice, but whether antifibrotic effects of carnosine extend to the heart is not known, nor are the mechanisms by which carnosine is acting. Here, we investigated whether oral carnosine was able to mitigate the adverse cardiac remodeling associated with diet induced obesity in a mouse model of enhanced lipid peroxidation (i.e., glutathione peroxidase 4 deficient mice, GPx4+/-), a model which mimics many of the pathophysiological aspects of metabolic syndrome and T2 diabetes in humans. Wild-type (WT) and GPx4+/-male mice were randomly fed a standard (CNTL) or high fat high sucrose diet (HFHS) for 16 weeks. Seven weeks after starting the diet, a subset of the HFHS mice received carnosine (80 mM) in their drinking water for duration of the study. Carnosine treatment led to a moderate improvement in glycemic control in WT and GPx4+/-mice on HFHS diet, although insulin sensitivity was not significantly affected. Interestingly, while our transcriptomic analysis revealed that carnosine therapy had only modest impact on global gene expression in the heart, carnosine substantially upregulated cardiac GPx4 expression in both WT and GPx4+/-mice on HFHS diet. Carnosine also significantly reduced protein carbonyls and iron levels in myocardial tissue from both genotypes on HFHS diet. Importantly, we observed a robust antifibrotic effect of carnosine therapy in hearts from mice on HFHS diet, which further in vitro experiments suggest is due to carnosine's ability to suppress collagen-cross-linking. Collectively, this study reveals antifibrotic potential of carnosine in the heart with obesity and illustrates key mechanisms by which it may be acting.

Acute Toxicity, Anti-diabetic, and Anti-cancerous Potential of Trillium Govanianum-conjugated Silver Nanoparticles in Balb/c Mice

BACKGROUND

The current study aimed to develop an economic plant-based therapeutic agent to improve the treatment strategies for diseases at the nano-scale because Cancer and Diabetes mellitus are major concerns in developing countries. Therefore, in vitro and in vivo antidiabetic and anti-cancerous activities of Trillium govanianum conjugated silver nanoparticles were assessed.

METHODS

In the current study synthesis of silver nanoparticles using Trillium govanianum and characterization were done using a scanning electron microscope, UV-visible spectrophotometer, and FTIR analysis. The in vitro and in vivo anti-diabetic and anti-cancerous potential (200 mg/kg and 400 mg/kg) were carried out.

RESULTS

It was discovered that Balb/c mice did not show any major alterations during observation of acute oral toxicity when administered orally both TGaqu (1000 mg/kg) and TGAgNPs (1000 mg/kg), and results revealed that 1000 mg/kg is not lethal dose as did not find any abnormalities in epidermal and dermal layers when exposed to TGAgNPs. In vitro studies showed that TGAgNPs could not only inhibit alpha-glucosidase and protein kinases but were also potent against the brine shrimp. Though, a significant reduction in blood glucose levels and significant anti-cancerous effects was recorded when alloxan-treated and CCl4-induced mice were treated with TGAgNPs and TGaqu.

CONCLUSION

Both in vivo and in vitro studies revealed that TGaqu and TGAgNPs are not toxic at 200 mg/kg, 400 mg/kg, and 1000 mg/kg doses and possess strong anti-diabetic and anti-cancerous effects due to the presence of phyto-constituents. Further, suggesting that green synthesized silver nanoparticles could be used in pharmaceutical industries to develop potent therapeutic agents.

Role of methylglyoxal and redox homeostasis in microbe-mediated stress mitigation in plants

One of the general consequences of stress in plants is the accumulation of reactive oxygen (ROS) and carbonyl species (like methylglyoxal) to levels that are detrimental for plant growth. These reactive species are inherently produced in all organisms and serve different physiological functions but their excessive accumulation results in cellular toxicity. It is, therefore, essential to restore equilibrium between their synthesis and breakdown to ensure normal cellular functioning. Detoxification mechanisms that scavenge these reactive species are considered important for stress mitigation as they maintain redox balance by restricting the levels of ROS, methylglyoxal and other reactive species in the cellular milieu. Stress tolerance imparted to plants by root-associated microbes involves a multitude of mechanisms, including maintenance of redox homeostasis. By improving the overall antioxidant response in plants, microbes can strengthen defense pathways and hence, the adaptive abilities of plants to sustain growth under stress. Hence, through this review we wish to highlight the contribution of root microbiota in modulating the levels of reactive species and thereby, maintaining redox homeostasis in plants as one of the important mechanisms of stress alleviation. Further, we also examine the microbial mechanisms of resistance to oxidative stress and their role in combating plant stress.

Oxidative modification of carbonic anhydrase by peroxynitrite trigger immune response in mice and rheumatic disease patients

BACKGROUND

Carbonic anhydrases (CA) are metalloenzymes with wide tissue distribution, involved in many important physiological processes, and in some rheumatic diseases, autoantibodies are formed against these enzymes. Recent studies have suggested that oxidative stress triggers anti-CA antibody formation. In this study, we aimed to investigate the effects of modification with oxidative/nitrosative stress end products on CA antigenicity in mice and the relationship between the modified CA autoantibodies and oxidant-antioxidant status in patients with rheumatoid arthritis (RA) and Sjögren's syndrome (SjS).

METHODS

CA I and CA II isoenzymes were isolated from human erythrocytes and modified with 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), and peroxynitrite (PN). Balb-c mice were immunized with these agents to determine the effects of modification on CA antigenicity. The autoantibody titers of modified CA isoenzymes were detected in patients. In addition MDA, 4-HNE, 3-nitrotyrosine (3-NT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured to assess the oxidant-antioxidant status in patients.

RESULTS

Modifications of carbonic anhydrase with oxidative stress end products, HNE, MDA and PN, lead to alterations in the immune response to these enzymes in mice. It was found that HNE and MDA decreased the antigenicity while PN increased. In addition, PN-modified CA autoantibody levels were found to be significantly different in both RA and SjS patients compared to their controls (p<0.05).

CONCLUSIONS

PN modifications can also trigger an immune response against CA isoenzymes in mice, and PN-modified CA I and CA II autoantibody titers were found at a significantly high level in both RA and SjS patients.

Multiple ammonia-induced episodes of hepatic encephalopathy provoke neuronal cell loss in bile-duct ligated rats

Background & Aims

Hepatic encephalopathy (HE) is defined as a reversible syndrome and therefore should resolve following liver transplantation (LT). However, neurological complications have been reported in up to 47% of LT recipients, which have been documented to be associated with a history of overt HE pre-LT. We hypothesise that multiple episodes of HE lead to permanent cell injury and exacerbate neurological dysfunction. Our goal was to evaluate the impact of cumulative HE episodes on neurological status and brain integrity in rats with chronic liver disease.

Methods

Episodes of overt HE (loss of righting reflex) were induced following injection of ammonium acetate in bile duct ligation (BDL) rats (BDL-Ammonia) every 4 days starting at week 3 post-BDL. Neurobehaviour was evaluated after the last episode. Upon sacrifice, plasma ammonia, systemic oxidative stress, and inflammation markers were assessed. Neuronal markers including neuron-specific nuclear antigen and SMI311 (anti-neurofilament marker) and apoptotic markers (cleaved caspase-3, Bax, and Bcl2) were measured. Total antioxidant capacity, oxidative stress marker (4-hydroxynonenal), and proinflammatory cytokines (tumour necrosis factor-alpha and interleukin-1β) were measured in brain (hippocampus, frontal cortex, and cerebellum). Proteomic analysis was conducted in the hippocampus.

Results

In hippocampus of BDL-Ammonia rats, cleaved caspase-3 and Bax/Bcl2 ratio were significantly increased, whereas NeuN and SMI311 were significantly decreased compared with BDL-Vehicle rats. Higher levels of oxidative stress-induced post-translational modified proteins were found in hippocampus of BDL-Ammonia group which were associated with a lower total antioxidant capacity.

Conclusions

Ammonia-induced episodes of overt HE caused neuronal cell injury/death in BDL rats. These results suggest that multiple bouts of HE can be detrimental on the integrity of the brain, translating to irreversibility and hence neurological complications post-LT.

Impact and implications

Hepatic encephalopathy (HE) is defined as a reversible neuropsychiatric syndrome resolving following liver transplantation (LT); however, ∼47% of patients demonstrate neurological impairments after LT, which are associated with a previous history of overt HE pre-LT. Our study indicates that multiple episodes of overt HE can cause permanent neuronal damage which may lead to neurological complications after LT. Nevertheless, preventing the occurrence of overt HE episodes is critical for reducing the risk of irreversible neuronal injury in patients with cirrhosis.

OP2113, a new drug for chronic hypoxia-induced pulmonary hypertension treatment in rat

BACKGROUND AND PURPOSE

Pulmonary hypertension (PH) is a cardiovascular disease characterised by an increase in pulmonary arterial (PA) resistance leading to right ventricular (RV) failure. Reactive oxygen species (ROS) play a major role in PH. OP2113 is a drug with beneficial effects on cardiac injuries that targets mitochondrial ROS. The aim of the study was to address the in vivo therapeutic effect of OP2113 in PH.

EXPERIMENTAL APPROACH

PH was induced by 3 weeks of chronic hypoxia (CH-PH) in rats treated with OP2113 or its vehicle via subcutaneous osmotic mini-pumps. Haemodynamic parameters and both PA and heart remodelling were assessed. Reactivity was quantified in PA rings and in RV or left ventricular (LV) cardiomyocytes. Oxidative stress was detected by electron paramagnetic resonance and western blotting. Mitochondrial mass and respiration were measured by western blotting and oxygraphy, respectively.

KEY RESULTS

In CH-PH rats, OP2113 reduced the mean PA pressure, PA remodelling, PA hyperreactivity in response to 5-HT, the contraction slowdown in RV and LV and increased the mitochondrial mass in RV. Interestingly, OP2113 had no effect on haemodynamic parameters, both PA and RV wall thickness and PA reactivity, in control rats. Whereas oxidative stress was evidenced by an increase in protein carbonylation in CH-PH, this was not affected by OP2113.

CONCLUSION AND IMPLICATIONS

Our study provides evidence for a selective protective effect of OP2113 in vivo on alterations in both PA and RV from CH-PH rats without side effects in control rats.

A review of the characteristic properties of selected tobacco chemicals and their associated etiological risks

OBJECTIVES

Despite the quantum of research findings on tobacco epidemic, a review on the formation characteristics of nicotine, aldehydes and phenols, and their associated etiological risks is still limited in literature. Accordingly, knowledge on the chemical properties and free radical formation during tobacco burning is an important subject towards unravelling the relationship between smoking behaviour and disease. This review investigates how scientific efforts have been advanced towards understanding the release of molecular products from the thermal degradation of tobacco, and harm reduction strategies among cigarette smokers in general. The mechanistic characteristics of nicotine and selected aldehydes are critically examined in this review. For the purpose of this work, articles published during the period 2004-2021 and archived in PubMed, Google Scholar, Medley, Cochrane, and Web of Science were used. The articles were selected based on the health impacts of cigarette smoking, tobacco burning kinetics, tobacco cessation and tobacco as a precursor for emerging diseases such as Covid-19.

CONTENT

The toxicity of cigarette smoke is directly correlated with its chemical composition derived from the pyrolysis of tobacco stem and leaves. Most of the harmful toxic substances are generated by pyrolysis during smoking and depends on pyrolysis conditions. Detailed studies have been conducted on the kinetics of nicotine by use of robust theoretical models in order to determine the rate constants of reactions in nicotine and those of nicotine dissociation via C-C and C-N scission, yielding pyridinyl and methyl radicals, respectively. Research has suggested that acetaldehyde enhances the effect of nicotine, which in turn reinforces addiction characteristics whereas acrolein and crotonaldehyde are ciliatoxic, and can inhibit lung clearance. On the other hand, phenol affects liver enzymes, lungs, kidneys, and the cardiovascular system while m-cresol attacks the nervous system.

SUMMARY AND OUTLOOK

The characteristics of chemical release during tobacco burning are very important in the tobacco industry and the cigarette smoking community. Understanding individual chemical formation from cigarette smoking will provide the necessary information needed to formulate sound tobacco reform policies from a chemical standpoint. Nonetheless, intense research is needed in this field in order to prescribe possible measures to deter cigarette smoking addiction and ameliorate the grave miseries bedevilling the tobacco smoking community.

Advance in Morchella sp. polysaccharides: Isolation, structural characterization and structure-activity relationship: A review

Morchella sp. is a kind of precious medicinal and edible fungus with a unique flavor and is rich in various amino acids and organic germanium needed by the human body. Most notably, Morchella sp. polysaccharides have attracted widespread attention due to their significant bioactivity in recent years. At present, extensive studies have been carried out on the extraction methods, structural characterization and activity evaluation of Morchella sp. polysaccharides, which provides a good theoretical basis for its further development and application. However, the systematic summary of the related research of Morchella sp. polysaccharides has not been reported yet. Therefore, this review mainly focused on the isolation and purification methods, structural characterization, biological activities and structure-activity relationship of Morchella sp. polysaccharides. This work will help to have a better in-depth understanding of Morchella sp. polysaccharides and provide a scientific basis and direct reference for more scientific and rational applications.

Potential antidepressant effects of a dietary supplement from Huáng qí and its complex in aged senescence-accelerated mouse prone-8 mice

Healthcare is an emerging industry with significant market potential in the 21st century. Therefore, this study aimed to evaluate the benefits of tube feeding Huáng qí and its complexes for 8 weeks on 3-month-old senescence-accelerated mouse prone-8 (SAMP8) mice, 48 in total, randomly divided into 3 groups including control, Huáng qí extract [820 mg/kg Body weight (BW)/day], and Huáng qí complexes (6.2 mL /kg BW/day), where each group consisted of males (n = 8) and females (n = 8). Behavioral tests (locomotion test and aging score assessment on week 6, the single-trial passive avoidance test on week 7, and the active shuttle avoidance test on week 8) were conducted to evaluate the ability of the mice to learn and remember. In addition, after sacrificing the animals, the blood and organs were measured for antioxidant and aging bioactivities, including malondialdehyde (MDA) content and superoxide dismutase (SOD) activity and catalase activities (CAT), and the effects on promoting aging in SAMP8 mice were investigated. The findings showed that Huáng qí enhanced locomotor performance and had anti-aging effects, with positive effects on health, learning, and memory in SAMP-8 mice (p < 0.05), whether applied as a single agent (820 mg/kg BW/day) or as a complex (6.2 mL/kg BW/day) (p < 0.05). Based on existing strengths, a more compelling platform for clinical validation of human clinical evidence will be established to enhance the development and value-added of astragalus-related products while meeting the diversified needs of the functional food market.

Aldehyde Dehydrogenase and Aldo-Keto Reductase Enzymes: Basic Concepts and Emerging Roles in Diabetic Retinopathy

Diabetic retinopathy (DR) is a complication of diabetes mellitus that can lead to vision loss and blindness. It is driven by various biochemical processes and molecular mechanisms, including lipid peroxidation and disrupted aldehyde metabolism, which contributes to retinal tissue damage and the progression of the disease. The elimination and processing of aldehydes in the retina rely on the crucial role played by aldehyde dehydrogenase (ALDH) and aldo-keto reductase (AKR) enzymes. This review article investigates the impact of oxidative stress, lipid-derived aldehydes, and advanced lipoxidation end products (ALEs) on the advancement of DR. It also provides an overview of the ALDH and AKR enzymes expressed in the retina, emphasizing their growing importance in DR. Understanding the relationship between aldehyde metabolism and DR could guide innovative therapeutic strategies to protect the retina and preserve vision in diabetic patients. This review, therefore, also explores various approaches, such as gene therapy and pharmacological compounds that have the potential to augment the expression and activity of ALDH and AKR enzymes, underscoring their potential as effective treatment options for DR.

The impact of e-cigarette exposure on different organ systems: A review of recent evidence and future perspectives

The use of electronic cigarettes (e-cigs) is rapidly increasing worldwide and is promoted as a smoking cessation tool. The impact of traditional cigs on human health has been well-defined in both animal and human studies. In contrast, little is known about the adverse effects of e-cigs exposure on human health. This review summarizes the impact of e-cigs exposure on different organ systems based on the rapidly expanding recent evidence from experimental and human studies. A number of growing studies have shown the adverse effects of e-cigs exposure on various organ systems. The summarized data in this review indicate that while e-cigs use causes less adverse effects on different organs compared to traditional cigs, its long-term exposure may lead to serious health effects. Data on short-term organ effects are limited and there is no sufficient evidence on long-term organ effects. Moreover, the adverse effects of secondhand and third hand e-cigs vapour exposure have not been thoroughly investigated in previous studies. Although some studies demonstrated e-cigs used as a smoking cessation tool, there is a lack of strong evidence to support it. While some researchers suggested e-cigs as a safer alternative to tobacco smoking, their long-term exposure health effects remain largely unknown. Therefore, more epidemiological and prospective studies including mechanistic studies are needed to address the potential adverse health effects of e-cigs to draw a firm conclusion about their safe use. A wide variation in e-cigs products and the lack of standardized testing methods are the major barriers to evaluating the existing data. Specific regulatory guidelines for both e-cigs components and the manufacturing process may be effective to protect consumer health.

The Janus-Faced Role of Lipid Droplets in Aging: Insights from the Cellular Perspective

It is widely accepted that nine hallmarks-including mitochondrial dysfunction, epigenetic alterations, and loss of proteostasis-exist that describe the cellular aging process. Adding to this, a well-described cell organelle in the metabolic context, namely, lipid droplets, also accumulates with increasing age, which can be regarded as a further aging-associated process. Independently of their essential role as fat stores, lipid droplets are also able to control cell integrity by mitigating lipotoxic and proteotoxic insults. As we will show in this review, numerous longevity interventions (such as mTOR inhibition) also lead to strong accumulation of lipid droplets in Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, and mammalian cells, just to name a few examples. In mammals, due to the variety of different cell types and tissues, the role of lipid droplets during the aging process is much more complex. Using selected diseases associated with aging, such as Alzheimer's disease, Parkinson's disease, type II diabetes, and cardiovascular disease, we show that lipid droplets are "Janus"-faced. In an early phase of the disease, lipid droplets mitigate the toxicity of lipid peroxidation and protein aggregates, but in a later phase of the disease, a strong accumulation of lipid droplets can cause problems for cells and tissues.

Protein adducts with lipid peroxidation products in patients with psoriasis

Psoriasis, one of the most frequent immune-mediated skin diseases, is manifested by numerous psoriatic lessons on the skin caused by excessive proliferation and keratinization of epidermal cells. These disorders of keratinocyte metabolism are caused by a pathological interaction with the cells of the immune system, including lymphocytes, which in psoriasis are also responsible for systemic inflammation. This is accompanied by oxidative stress, which promotes the formation of lipid peroxidation products, including reactive aldehydes and isoprostanes, which are additional pro-inflammatory signaling molecules. Therefore, the presented review is focused on highlighting changes that occur during psoriasis development at the level of lipid peroxidation products, including 4-hydroxynonenal, 4-oxononenal, malondialdehyde, and acrolein, and their influence on protein structures. Furthermore, we will examine inducing agents of cellular functioning, as well as intercellular signaling. These lipid peroxidation products can form adducts with a variety of proteins with different functions in the body, including proteins within skin cells and cells of the immune system. This is especially true in autoimmune diseases such as psoriasis. For example, these changes concern proteins involved in maintaining redox homeostasis or pro-inflammatory signaling. Therefore, the formation of such adducts should attract attention, especially during the design of preventive cosmetics or anti-psoriasis therapies.

Reuse of treated urban wastewater on the growth and physiology of Medicago sativa L. cv. Gea and Petroselinum crispum L. cv. Commun: correlation with oxydative stress and DNA damage

The freshwater scarcity is one of the major environmental problems, which is why the water reuse has become a possible remedy to cope with the shortage of water needed for agriculture irrigation. This study focuses on the evaluation of the irrigation effect with treated effluent from wastewater treatment plant in Tunisia on parsley (Petroselinum crispum L. cv. Commun) used as human food and alfalfa (Medicago sativa L. cv. Gea) as animal food. In vitro germination test was conducted at different dilution levels of wastewater as rejected into the environment (25, 50, and 100%) and wastewater with further treatment (TWW). Results have shown that wastewater with dilution of 25% as well as TWW positively affected the physiological parameters in comparison with the dilutions 50 and 100%. However, the tap water (TW) applied as control treatment has shown the best effects. Oxidative stress evaluated by malondialdehyde (MDA) content was in agreement with the physiological results and showed that the most stressed seeds were those treated with the dilutions 50 and 100%. A pot trial was also conducted to evaluate the suitability of WW and TWW in comparison to TW. Results have shown that TWW is more adapted than WW for irrigation as an improvement of growth and physiological parameters was recorded. Oxidative stress assessed with MDA and proline content has shown that plants irrigated with WW significantly accumulate MDA and proline compared to TWW. The TW has shown the lowest values. DNA damage was evaluated by extraction and agarose gel electrophoresis. It has revealed degradation of DNA for plants irrigated with WW. According to these results, it can be concluded that TWW can be used for irrigation of plants destined for human or animal foods. So, it can be a hydric alternative to resolve the problem of water deficit in semi-arid countries.

Lipid Aldehydes 4-Hydroxynonenal and 4-Hydroxyhexenal Exposure Differentially Impact Lipogenic Pathways in Human Placenta

Long chain polyunsaturated fatty acids (LCPUFAs), such as the omega-6 (n-6) arachidonic acid (AA) and n-3 docosahexanoic acid (DHA), have a vital role in normal fetal development and placental function. Optimal supply of these LCPUFAs to the fetus is critical for improving birth outcomes and preventing programming of metabolic diseases in later life. Although not explicitly required/recommended, many pregnant women take n-3 LCPUFA supplements. Oxidative stress can cause these LCPUFAs to undergo lipid peroxidation, creating toxic compounds called lipid aldehydes. These by-products can lead to an inflammatory state and negatively impact tissue function, though little is known about their effects on the placenta. Placental exposure to two major lipid aldehydes, 4-hydroxynonenal (4-HNE) and 4-hydroxyhexenal (4-HHE), caused by peroxidation of the AA and DHA, respectively, was examined in the context of lipid metabolism. We assessed the impact of exposure to 25 μM, 50 μM and 100 μM of 4-HNE or 4-HHE on 40 lipid metabolism genes in full-term human placenta. 4-HNE increased gene expression associated with lipogenesis and lipid uptake (ACC, FASN, ACAT1, FATP4), and 4-HHE decreased gene expression associated with lipogenesis and lipid uptake (SREBP1, SREBP2, LDLR, SCD1, MFSD2a). These results demonstrate that these lipid aldehydes differentially affect expression of placental FA metabolism genes in the human placenta and may have implications for the impact of LCPUFA supplementation in environments of oxidative stress.

The Role of Potential Oxidative Biomarkers in the Prognosis of Acute Ischemic Stroke and the Exploration of Antioxidants as Possible Preventive and Treatment Options

Ischemic strokes occur when the blood supply to a part of the brain is interrupted or reduced due to arterial blockage, and it often leads to damage to brain cells or death. According to a myriad of experimental studies, oxidative stress is an important pathophysiological mechanism of ischemic stroke. In this narrative review, we aimed to identify how the alterations of oxidative stress biomarkers could suggest a severity-reflecting diagnosis of ischemic stroke and how these interactions may provide new molecular targets for neuroprotective therapies. We performed an eligibility criteria-based search on three main scientific databases. We found that patients with acute ischemic stroke are characterized by increased oxidative stress markers levels, such as the total antioxidant capacity, F2-isoprostanes, hydroxynonenal, total and perchloric acid oxygen radical absorbance capacity (ORACTOT and ORACPCA), malondialdehyde (MDA), myeloperoxidase, and urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine. Thus, acute ischemic stroke is causing significant oxidative stress and associated molecular and cellular damage. The assessment of these molecular markers could be useful in diagnosing ischemic stroke, finding its causes, predicting its severity and outcomes, reducing its impact on the cellular structures of the brain, and guiding preventive treatment towards antioxidant-based therapy as novel therapeutic alternatives.

Emerging Therapy for Diabetic Cardiomyopathy: From Molecular Mechanism to Clinical Practice

Diabetic cardiomyopathy is characterized by abnormal myocardial structure or performance in the absence of coronary artery disease or significant valvular heart disease in patients with diabetes mellitus. The spectrum of diabetic cardiomyopathy ranges from subtle myocardial changes to myocardial fibrosis and diastolic function and finally to symptomatic heart failure. Except for sodium–glucose transport protein 2 inhibitors and possibly bariatric and metabolic surgery, there is currently no specific treatment for this distinct disease entity in patients with diabetes. The molecular mechanism of diabetic cardiomyopathy includes impaired nutrient-sensing signaling, dysregulated autophagy, impaired mitochondrial energetics, altered fuel utilization, oxidative stress and lipid peroxidation, advanced glycation end-products, inflammation, impaired calcium homeostasis, abnormal endothelial function and nitric oxide production, aberrant epidermal growth factor receptor signaling, the activation of the renin–angiotensin–aldosterone system and sympathetic hyperactivity, and extracellular matrix accumulation and fibrosis. Here, we summarize several important emerging treatments for diabetic cardiomyopathy targeting specific molecular mechanisms, with evidence from preclinical studies and clinical trials.

Morphological, immunohistochemical, and biochemical study on the ameliorative effect of gallic acid against bisphenol A-induced nephrotoxicity in male albino rats

This study aimed to determine the effect of gallic acid (GA) on ameliorating bisphenol A (BPA) nephrotoxicity in male rat kidneys. Forty rats were assigned randomly into two groups: control (ten animals) and BPA (40 mg/kg bwt) (thirty animals), the second group was divided into three subgroups: BPA alone, BPA + G50 (50 mg/kg bwt), and BPA + G200 (200 mg/kg bwt). The biochemical analysis included measurements of the contents of nitric oxide, lipid peroxidation, reactive oxygen species, and cytokines (interleukin-1α and interleukin-6) in the kidney. The antioxidant enzymes catalase and superoxide dismutase were also measured in the kidney. Kidney function was assessed by determining uric acid, urea, and creatinine levels. The morphological investigations included hematoxylin and eosin staining for assessing the general histology and determining the glomerular and corpuscular areas, the tubular cell degeneration mean area, and the mean leukocyte infiltration area. Also, collagen fiber intensity and polysaccharide content were analyzed. Furthermore, immunohistochemical, morphometric, and ultrastructural studies were carried out. The results revealed morphological, immunohistochemical, and biochemical alterations in the kidney. Most of these changes showed a satisfactory improvement of kidney damage when BPA-administered rats were treated with GA at both doses. In conclusion, GA exhibited a strong protective effect against BPA-induced nephrotoxicity.

Deuterated polyunsaturated fatty acids provided protection against oxidative stress in ocular fibroblasts derived from glaucoma patients

Glaucoma is a complex neurodegenerative disease of the optic nerve that leads to irreversible sight loss. Lowering intraocular pressure (IOP) medically or surgically represents the mainstay of treatment but despite adequate treatment optic nerve function can continue to deteriorate leading to blindness. There is significant clinical and experimental evidence that oxidative stress is involved in the pathogenesis of glaucoma. Decreasing the formation of lipid peroxidation products or scavenging them chemically could be beneficial in limiting the deleterious effects of oxidative stress in glaucoma. A solution to control the susceptibility of PUFAs to noxious lipid peroxidation reactions is by regioselective deuteration. Deuterium incorporated into PUFAs at bis-allylic positions (D-PUFAs) inhibits the rate-limiting step of lipid peroxidation. In this study, we have shown that Tenon's ocular fibroblasts from glaucoma patients have significantly increased basal oxidative stress compared to non-glaucomatous control patients. Furthermore, we have shown that deuterated polyunsaturated fatty acids (D-PUFAs) provide an enhanced rescue of menadione induced lipid peroxidation in both non-glaucomatous and glaucomatous Tenon's ocular fibroblasts using malondialdehyde (MDA) levels as a marker. Our study suggests that D-PUFAs may provide a potentially safe and effective method to reduce cytotoxic oxidative stress in glaucoma.

The protective role of nutritional antioxidants against oxidative stress in thyroid disorders

An imbalance between pro-oxidative and antioxidative cellular mechanisms is oxidative stress (OxS) which may be systemic or organ-specific. Although OxS is a consequence of normal body and organ physiology, severely impaired oxidative homeostasis results in DNA hydroxylation, protein denaturation, lipid peroxidation, and apoptosis, ultimately compromising cells' function and viability. The thyroid gland is an organ that exhibits both oxidative and antioxidative processes. In terms of OxS severity, the thyroid gland's response could be physiological (i.e. hormone production and secretion) or pathological (i.e. development of diseases, such as goitre, thyroid cancer, or thyroiditis). Protective nutritional antioxidants may benefit defensive antioxidative systems in resolving pro-oxidative dominance and redox imbalance, preventing or delaying chronic thyroid diseases. This review provides information on nutritional antioxidants and their protective roles against impaired redox homeostasis in various thyroid pathologies. We also review novel findings related to the connection between the thyroid gland and gut microbiome and analyze the effects of probiotics with antioxidant properties on thyroid diseases.

Natural flavonoids derived from herbal medicines are potential anti-atherogenic agents by inhibiting oxidative stress in endothelial cells

As the common pathological basis of various cardiovascular diseases, the morbidity and mortality of atherosclerosis (AS) have increased in recent years. Unfortunately, there are still many problems in the treatment of AS, and the prevention and treatment of the disease is not ideal. Up to now, the occurrence and development of AS can roughly include endothelial cell dysfunction, vascular smooth muscle cell proliferation, inflammation, foam cell production, and neoangiogenesis. Among them, endothelial dysfunction, as an early event of AS, plays a particularly important role in promoting the development of AS. In addition, oxidative stress occurs throughout the causes of endothelial dysfunction. Some previous studies have shown that flavonoids derived from herbal medicines are typical secondary metabolites. Due to its structural presence of multiple active hydroxyl groups, it is able to exert antioxidant activity in diseases. Therefore, in this review, we will search PubMed, Web of Science, Elesvier, Wliey, Springer for relevant literature, focusing on flavonoids extracted from herbal medicines, and summarizing how they can prevent endothelial dysfunction by inhibiting oxidative stress. Meanwhile, in our study, we found that flavonoid represented by quercetin and naringenin showed superior protective effects both in vivo and in vitro, suggesting the potential of flavonoid compounds in the treatment of AS.

Gut microbial characteristical comparison reveals potential anti-aging function of Dubosiella newyorkensis in mice

INTRODUCTION

Previous study has indicated Dubosiella newyorkensis may act as a potential probiotic in age-related diseases. However, its detailed role in aging has not yet been promulgated. This study aimed to explore the potential anti-aging role of Dubosiella newyorkensis by comparing the anti-aging effect of resveratrol in young and old mice.

METHOD

Measurement of intestinal aging-related factors in colon and serum, and vascular endothelial function-related factors in serum were performed by enzyme-linked immunosorbent assay (ELISA). Gut microbial analysis of intestinal contents were identified by 16S rRNA gene sequencing.

RESULTS

The effect of Dubosiella newyorkensis on reducing malondialdehyde (MDA) and increasing superoxide dismutase (SOD) in aged mice were greater than that of resveratrol. While the effect of Dubosiella newyorkensis on nitric oxide (NO) level was less than that of resveratrol, the reduction of vascular endothelial growth factor (VEGF) and pentosidine (PTD) was better than that of resveratrol in young mice. In young mice, Dubosiella newyorkensis promoted an increase in the beneficial genus Lactobacillus, Bifidobacterium and Ileibacterium less effectively as compared with resveratrol treatment. In aged mice, Dubosiella newyorkensis promoted the increase of Bifidobacterium, Ileibacterium less effectively than resveratrol, and promoted the increase of Akkermansia, Staphylococcus, Verrucomicrobiota expression better as compared with resveratrol treatment. Both young and old mice showed the same results for the remaining markers, including changes in gut microbial composition and predictions of function.

CONCLUSION

Dubosiella newyorkensis has similar anti-aging functions with resveratrol. Dubosiella newyorkensis may even be more effective than resveratrol in reducing oxidative stress, improving vascular endothelial function, and redistributing gut microbiota. The research provides an innovative strategy of Dubosiella newyorkensis to improve aging.

Potential Diagnostic and Monitoring Biomarkers of Obstructive Sleep Apnea-Umbrella Review of Meta-Analyses

Obstructive sleep apnea (OSA) is a prevalent, underdiagnosed disease that imposes a significant impact on the health and wellbeing of patients and a financial burden on individuals, their families, and society. Development of new methods of testing other than an overnight sleep study, such as measurement of serum or plasma biomarkers, may provide an easier diagnostic process to identify patients with OSA and allow earlier initiation of treatment, which might prevent serious comorbidities. We conducted a systematic review and quality assessment of available meta-analyses regarding potential diagnostic and monitoring biomarkers of obstructive sleep apnea. A total of 14 sets of candidate biomarkers displayed differences in levels or concentrations in OSA patients compared to non-OSA controls, and decreased after OSA treatment: CRP, IL-6, TNF-α, Il-8, HCY, ICAM-1, VCAM-1, VEGF, TC, LDLc, HDLc, TG, leptin, MDA, ALT, AST, IGF-1, adiponectin, and cortisol. This review summarizes the evidence for OSA-associated potential biomarkers and demonstrates that the quality of available studies, as measured by AMSTAR2, is often low and associated with a high risk of bias.

Increased unsaturated lipids underlie lipid peroxidation in synucleinopathy brain

Lipid peroxidation is a process of oxidative degradation of cellular lipids that is increasingly recognized as an important factor in the pathogenesis of neurodegenerative diseases. We were therefore interested in the manifestation of lipid peroxidation in synucleinopathies, a group of neurodegenerative diseases characterized by the central pathology of α-synuclein aggregates, including Parkinson's disease, multiple system atrophy, dementia with Lewy bodies and Alzheimer's disease with Lewy bodies. We assessed lipid peroxidation products, lipid aldehydes, in the amygdala, a common disease-affected region in synucleinopathies, and in the visual cortex, a disease-unaffected region. We found that the levels of lipid aldehydes were significantly increased in the amygdala, but not in the visual cortex. We hypothesized that these increases are due to increases in the abundance of unsaturated lipids, since lipid aldehydes are formed from unsaturated lipids. We undertook a comprehensive analysis of membrane lipids using liquid chromatography-mass spectrometry and found that unsaturated phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and sphingomyelin were specifically elevated in the amygdala and correlated with increases in lipid aldehydes. Furthermore, unsaturated phosphatidylethanolamine levels were associated with soluble α-synuclein. Put together, these results suggest that manifestation of lipid peroxidation is prevalent in synucleinopathies and is likely to be due to increases in unsaturated membrane lipids. Our findings underscore the importance of lipid peroxidation in α-synuclein pathology and in membrane structure maintenance.

Overview of the Mechanisms of Oxidative Stress: Impact in Inflammation of the Airway Diseases

Inflammation of the human lung is mediated in response to different stimuli (e.g., physical, radioactive, infective, pro-allergenic or toxic) such as cigarette smoke and environmental pollutants. They often promote an increase in inflammatory activities in the airways that manifest themselves as chronic diseases (e.g., allergic airway diseases, asthma, chronic bronchitis/chronic obstructive pulmonary disease (COPD) or even lung cancer). Increased levels of oxidative stress (OS) reduce the antioxidant defenses, affect the autophagy/mitophagy processes, and the regulatory mechanisms of cell survival, promoting inflammation in the lung. In fact, OS potentiate the inflammatory activities in the lung, favoring the progression of chronic airway diseases. OS increases the production of reactive oxygen species (ROS), including superoxide anions (O₂^-), hydroxyl radicals (OH) and hydrogen peroxide (H₂O₂), by the transformation of oxygen through enzymatic and non-enzymatic reactions. In this manner, OS reduces endogenous antioxidant defenses in both nucleated and non-nucleated cells. The production of ROS in the lung can derive from both exogenous insults (cigarette smoke or environmental pollution) and endogenous sources such as cell injury and/or activated inflammatory and structural cells. In this review, we describe the most relevant knowledge concerning the functional interrelation between the mechanisms of OS and inflammation in airway diseases.

Lipid hydroperoxides and oxylipins are mediators of denervation induced muscle atrophy

Loss of innervation is a key driver of age associated muscle atrophy and weakness (sarcopenia). Our laboratory has previously shown that denervation induced atrophy is associated with the generation of mitochondrial hydroperoxides and lipid mediators produced downstream of cPLA2 and 12/15 lipoxygenase (12/15-LOX). To define the pathological impact of lipid hydroperoxides generated in denervation-induced atrophy in vivo, we treated mice with liproxstatin-1, a lipid hydroperoxide scavenger. We treated adult male mice with 5 mg/kg liproxstain-1 or vehicle one day prior to sciatic nerve transection and daily for 7 days post-denervation before tissue analysis. Liproxstatin-1 treatment protected gastrocnemius mass and fiber cross sectional area (∼40% less atrophy post-denervation in treated versus untreated mice). Mitochondrial hydroperoxide generation was reduced 80% in vitro and by over 65% in vivo by liproxstatin-1 treatment in denervated permeabilized muscle fibers and decreased the content of 4-HNE by ∼25% post-denervation. Lipidomic analysis revealed detectable levels of 25 oxylipins in denervated gastrocnemius muscle and significantly increased levels for eight oxylipins that are generated by metabolism of fatty acids through 12/15-LOX. Liproxstatin-1 treatment reduced the level of three of the eight denervation-induced oxylipins, specifically 15-HEPE, 13-HOTrE and 17-HDOHE. Denervation elevated protein degradation rates in muscle and treatment with liproxstatin-1 reduced rates of protein breakdown in denervated muscle. In contrast, protein synthesis rates were unchanged by denervation. Targeted proteomics revealed a number of proteins with altered expression after denervation but no effect of liproxstain-1. Transcriptomic analysis revealed 203 differentially expressed genes in denervated muscle from vehicle or liproxstatin-1 treated mice, including ER stress, nitric oxide signaling, Gαi signaling, glucocorticoid receptor signaling, and other pathways. Overall, these data suggest lipid hydroperoxides and oxylipins are key drivers of increased protein breakdown and muscle loss associated with denervation induced atrophy and a potential target for sarcopenia intervention.

Chimeric galectin-3 and collagens: Biomarkers and potential therapeutic targets in fibroproliferative diseases

Fibrosis, stiffening and scarring of an organ/tissue due to genetic abnormalities, environmental factors, infection, and/or injury, is responsible for > 40% of all deaths in the industrialized world, and to date, there is no cure for it despite extensive research and numerous clinical trials. Several biomarkers have been identified, but no effective therapeutic targets are available. Human galectin-3 is a chimeric gene product formed by the fusion of the internal domain of the collagen alpha gene [N-terminal domain (ND)] at the 5'-end of galectin-1 [C-terminal domain (CRD)] that appeared during evolution together with vertebrates. Due to the overlapping structural similarities between collagen and galectin-3 and their shared susceptibility to cleavage by matrix metalloproteases to generate circulating collagen-like peptides, this review will discuss present knowledge on the role of collagen and galectin-3 as biomarkers of fibrosis. We will also highlight the need for transformative approaches targeting both the ND and CRD domains of galectin-3, since glycoconjugate binding by the CRD is triggered by ND-mediated oligomerization and the therapies targeted only at the CRD have so far achieved limited success.

Reactivity of Vitamin E as an Antioxidant in Red Meat and the Stomach Medium

The stomach is a bioreactor and an important intersection of biochemical reactions that affect human health. Lipid peroxidation of meat in the stomach medium generates malondialdehyde (MDA), which is absorbed from the gut into human plasma and modifies low-density lipoprotein (LDL) to MDA-LDL. We found in the stomach medium (pH 3.0) a high antioxidant activity of vitamin E against meat lipid peroxidation, almost 35-fold higher than at pH 6.3. In the stomach medium, the antioxidant activity of vitamin E on meat lipid peroxidation was 20-fold higher than that of catechin. Vitamin E, at pH 3.0, acts synergistically with metmyoglobin (MbFe⁺³), as a peroxidase/antioxidant couple. The synergistic effect of MbFe⁺³/vitamin E was almost 150-fold higher than the antioxidant effect achieved by MbFe⁺³/catechin. The meat antioxidant activity was maintained continuously by addition of a low concentration of vitamin E, catechin, and vitamin C, preventing the propagation of lipid oxidation, reactive aldehyde generation, and the loss of vitamin E.

Hydrogen exerts neuroprotective effects by inhibiting oxidative stress in experimental diabetic peripheral neuropathy rats

Diabetic peripheral neuropathy (DPN) is a complex disorder caused by long-standing diabetes. Oxidative stress was considered the critical creed in this DPN pathophysiology. Hydrogen has antioxidative effects on diabetes mellitus and related complications. However, there is still no concern on the beneficial effects of hydrogen in DPN. This paper aimed to evaluate the effects of exogenous hydrogen to reduce the severity of DPN in streptozotocin-induced diabetic rats. Compared with hydrogen-rich saline treatment, hydrogen inhalation significantly reduced blood glucose levels in diabetic rats in the 4^th and 8^th weeks. With regard to nerve function, hydrogen administration significantly attenuated the decrease in the velocity of motor nerve conduction in diabetic animals. In addition, hydrogen significantly attenuated oxidative stress by reducing the level of malondialdehyde, reactive oxygen species, and 8-hydroxy-2-deoxyguanosine and meaningfully enhanced the antioxidant capability by partially restoring the activities of superoxide dismutase. Further studies showed that hydrogen significantly upregulated the expression of nuclear factor erythroid-2-related factor 2 and downstream proteins such as catalase and hemeoxygenase-1 in the nerves of diabetic animals. Our paper showed that hydrogen exerts significant protective effects in DPN by downregulating oxidative stress via the pathway of nuclear factor erythroid-2-related factor 2, which suggests its potential value in clinical applications.