Biological effect of protein modifications by lipid peroxidation products

Targeting ferroptosis using Chinese herbal compounds to treat respiratory diseases

BACKGROUND

Respiratory diseases pose a grave threat to human life. Therefore, understanding their pathogenesis and therapeutic strategy is important. Ferroptosis is a novel type of iron-dependent programmed cell death, distinct from apoptosis, necroptosis, and autophagy, characterised by iron, reactive oxygen species, and lipid peroxide accumulation, as well as glutathione (GSH) depletion and GSH peroxidase 4 (GPX4) inactivation. A close association between ferroptosis and the onset and progression of respiratory diseases, including chronic obstructive pulmonary disease, acute lung injury, bronchial asthma, pulmonary fibrosis, and lung cancer, has been reported. Recent studies have shown that traditional Chinese medicine (TCM) compounds exhibit unique advantages in the treatment of respiratory diseases owing to their natural properties and potential efficacy. These compounds can effectively regulate ferroptosis by modulating several key signalling pathways such as system Xc- -GSH-GPX4, NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1, thus playing a positive role in improving respiratory diseases.

PURPOSE

This comprehensive review systematically outlines the regulatory role of ferroptosis in the onset and progression of respiratory diseases and provides evidence for treating respiratory diseases by targeting ferroptosis with TCM compounds. These insights aim to offer potential remedies for the clinical prevention and treatment of respiratory diseases.

STUDY DESIGN AND METHODS

We searched scientific databases PubMed, Web of Science, Scopus, and CNKI using keywords such as "ferroptosis","respiratory diseases","chronic obstructive pulmonary disease","bronchial asthma","acute lung injury","pulmonary fibrosis","lung cancer","traditional Chinese medicine","traditional Chinese medicine compound","monomer", and "natural product" to retrieve studies on the therapeutic potential of TCM compounds in ameliorating respiratory diseases by targeting ferroptosis. The retrieved data followed PRISMA criteria (preferred reporting items for systematic review).

RESULTS

TCM compounds possess unique advantages in treating respiratory diseases, stemming from their natural origins and proven clinical effectiveness. TCM compounds can exert therapeutic effects on respiratory diseases by regulating ferroptosis, which mainly involves modulation of pathways such as system Xc- -GSH-GPX4,NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1.

CONCLUSION

TCM compounds have demonstrated promising potential in improving respiratory diseases through the regulation of ferroptosis. The identification of specific TCM-related inducers and inhibitors of ferroptosis holds great significance in developing more effective strategies. However, current research remains confined to animal and cellular studies, emphasizing the imperative for further verifications through high-quality clinical data.

Malondialdehyde and Zinc May Relate to Severity of Microvascular Complications in Diabetes: A Preliminary Study on Older Adults with Type 2 Diabetes Mellitus in Northeast China

Background

Serum trace elements and oxidative stress factors are related to diabetic microvascular complications. The study was to investigate the complex relationship between trace elements, oxidative stress factors, and the severity of microvascular complications of diabetes in older adults.

Methods

The present study included patients with or without type 2 diabetes, and blood glucose, blood lipids, trace elements (iron, magnesium, zinc), oxidative stress factors (malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC)) were evaluated. Risk factors for the severity of diabetic microvascular complications in older adults with diabetes were also estimated.

Results

There were statistically significant differences in fasting blood glucose (FBG), triglycerides (TG), low density lipoprotein (LDL), glycated hemoglobin (HbAlc), MDA, NO, SOD, T-AOC, magnesium, and zinc between the two groups (P<0.05). Iron (rZinc = 0.147, rSOD = 0.180, rT-AOC = 0.193, P < 0.05) was positively correlated with zinc, SOD and T-AOC. Iron was negatively correlated with MDA (rMDA = -0.146, P < 0.05). Magnesium was positively correlated with SOD (rMagnesium = 0.147, P < 0.05). Zinc (rSOD = 0.616, rT-AOC = 0.575, P < 0.01) was positively correlated with SOD and T-AOC. Zinc (rMDA =-0.636, rNO=-0.616, P<0.01) was positively correlated with MDA and negatively correlated with NO. The course of disease (18.653, [5.726; 60.764], P <0.01), FBG (1.265, [1.059; 1.511], P <0.05), HbAlc (1.545, [1.431; 1.680], P <0.01), MDA (2.989, [1.900; 4.702], P <0.01) were risk factor for the severity of diabetic microvascular complications. Zinc (0.680, [0.503; 0.919], P < 0.05) and SOD (0.820, [0.698; 0.964], P < 0.05) were protective factors for the severity of diabetic microvascular complications.

Conclusion

Serum trace elements are related to oxidative stress levels in older adults with type 2 diabetes. The more stable trace element in older adults with diabetes, the lower the oxidative stress and the fewer microvascular complications of diabetes.

Reactive oxygen species produced by photodynamic therapy enhance docosahexaenoic acid lipid peroxidation and induce the death of breast cancer cells

Breast cancer remains a serious threat to women's physical and emotional health. The combination therapies can overcome the deficiency of single therapy, enhance the therapeutic effects and reduce the side effects at the same time. In this study, we synthesize a novel nanomedicine that enhanced the therapeutic effects of breast cancer treatment by combining photodynamic therapy and chemotherapy. The doxorubicin (DOX) and photosensitizer methyl pyropheophorbide-a (MPPa) are loaded into the nano-drug delivery system as DPSPFA/MPPa/DOX. In response to near-infrared (NIR) laser, the drugs were quickly released to the cancer cells. The MPPa produces reactive oxygen species (ROS) under the action of photodynamics. Unsaturated fatty acids with ROS promotes lipid peroxidation and the combination of chemotherapy and photodynamic therapy. The data shows that the DPSPFA/MPPa/DOX has a spherical shape, good dispersibility and stability, and the particle size is roughly 200 nm. The drug loading capability of DOX is about 13 %. Both of MCF7 cell model in vitro and breast cancer model in vivo, DPSPFA/MPPa/DOX showed an excellent anti-tumor effect of 86.9 % and without any obvious side effects. These findings might offer potential for a new approach for breast cancer treatment.

Use of Lactoperoxidase Inhibitory Effects to Extend the Shelf Life of Meat and Meat Products

Lactoperoxidase (LP) is an important enzyme of the salivary and mammary glands. It has been proven to increase the shelf life of raw milk by inhibiting the growth of bacteria, especially Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Pseudomonas spp. The aim of this work was to verify the use of LP to extend the shelf life of meat products. In vitro experiments showed inhibitory effects on the selected bacteria (Listeria innocua (ATCC 33090), Staphylococcus saprophyticus (CP054440.1), and Pseudomonas fluorescens (ATCC 13525) due to a prolongation of the lag phase of growth curves. A lower increase in viable counts (p < 0.05) was also found by testing pork cubes' surface treated with LP solution (5%) + L. innocua and stored for 7 days at 15 °C. LP has also been studied at concentrations of 0.25 and 0.50% in meat products (pork ham and pâté) during refrigerated storage (4 °C for 28 days). Lower viable counts were observed throughout the storage experiment, especially for 0.50% LP (p < 0.05). Meat products containing LP also showed lower levels of oxidation (MAD) (p < 0.05). According to these results, LP could extend the shelf life of a wider range of products.

A patient-based iPSC-derived hepatocyte model of alcohol-associated cirrhosis reveals bioenergetic insights into disease pathogenesis

Only ~20% of heavy drinkers develop alcohol cirrhosis (AC). While differences in metabolism, inflammation, signaling, microbiome signatures and genetic variations have been tied to the pathogenesis of AC, the key underlying mechanisms for this interindividual variability, remain to be fully elucidated. Induced pluripotent stem cell-derived hepatocytes (iHLCs) from patients with AC and healthy controls differ transcriptomically, bioenergetically and histologically. They include a greater number of lipid droplets (LDs) and LD-associated mitochondria compared to control cells. These pre-pathologic indicators are effectively reversed by Aramchol, an inhibitor of stearoyl-CoA desaturase. Bioenergetically, AC iHLCs have lower spare capacity, slower ATP production and their mitochondrial fuel flexibility towards fatty acids and glutamate is weakened. MARC1 and PNPLA3, genes implicated by GWAS in alcohol cirrhosis, show to correlate with lipid droplet-associated and mitochondria-mediated oxidative damage in AC iHLCs. Knockdown of PNPLA3 expression exacerbates mitochondrial deficits and leads to lipid droplets alterations. These findings suggest that differences in mitochondrial bioenergetics and lipid droplet formation are intrinsic to AC hepatocytes and can play a role in its pathogenesis.

A novel fluorescent probe with a large Stokes shift for colorimetric and selective detection of cysteine in water, milk, cucumber, pear and tomato

Cysteine is an important amino acid that is related to human health and food safety. How to effectively detect Cys in food has received widespread attention. Compared with other methods, fluorescent probes have the advantages of simple operation, high sensitivity, and good selectivity. Therefore, a selective fluorescence probe 2 for Cys in food was designed and synthesized. Probe 2 employed the acrylate group as a thiol-recognition site for Cys, which endowed probe 2 with better selectivity for Cys over Hcy and GSH. The recognition pathway underwent Michael addition, intramolecular cyclization, and concomitant release of the piperideine-based fluorophore, along with a chromogenic change from yellow to orange. This pathway was supported by 1H NMR analysis and DFT calculations. In addition, probe 2 displays a linear response to Cys concentrations (0-30 μM), low detection limit (0.89 μM), and large Stokes shift (125 nm). Overall, probe 2 showed great application potential for the quantitative determination of Cys in water, milk, cucumber, pear and tomato.

The Intricate Balance between Life and Death: ROS, Cathepsins, and Their Interplay in Cell Death and Autophagy

Cellular survival hinges on a delicate balance between accumulating damages and repair mechanisms. In this intricate equilibrium, oxidants, currently considered physiological molecules, can compromise vital cellular components, ultimately triggering cell death. On the other hand, cells possess countermeasures, such as autophagy, which degrades and recycles damaged molecules and organelles, restoring homeostasis. Lysosomes and their enzymatic arsenal, including cathepsins, play critical roles in this balance, influencing the cell's fate toward either apoptosis and other mechanisms of regulated cell death or autophagy. However, the interplay between reactive oxygen species (ROS) and cathepsins in these life-or-death pathways transcends a simple cause-and-effect relationship. These elements directly and indirectly influence each other's activities, creating a complex web of interactions. This review delves into the inner workings of regulated cell death and autophagy, highlighting the pivotal role of ROS and cathepsins in these pathways and their intricate interplay.

Oxidized phospholipid-protein adducts: The future targets of interest

Phospholipids are key biomolecules with important roles as components of membranes, lipoproteins and as signalling molecules. However, phospholipids are quite prone to oxidation. Upon oxidation they generate several types of oxidation products including long chain oxidation products, as hydroperoxyl and hydroxy derivatives, and highly reactive oxidation products, like small aldehydes and truncated oxidized phospholipids. The formation of protein adducts with small electrophilic aldehydes (like malondialdehyde) is now well studied, however, the aggregation of proteins with truncated oxidized phospholipids lacks research. This paper provides a short overview of the formation of protein adducts with truncated oxidized phospholipids as well as a gathering of the research on this topic. The literature found reports the synthesis, detection and fragmentation of this type of adducts, mainly focusing on truncated oxidized phospholipid' products from phosphatidylcholine class and few peptides and proteins, as human serum albumin and Apo B100, leaving unattended the screening in vivo and in disease correlation, thus lacking possible association with their biological role. These adducts are a consequence of oxidative modifications to important biomolecules and their involvement in the organism is still unclear, revealing the urgent need for more investigation in this area.

Monitoring of carbon dioxide and equilibrium moisture content for early detection of physicochemical and morphological changes in soybeans stored in vertical silos

In the context of grain storage, impurities and soybeans defects in soybeans can significantly impact the equilibrium moisture content. This, cause moisture migration and heating of the stored product, leading to increased respiratory activity. Furthermore, temperature measurements within stored grain mass do not provide sufficient information for effective grain quality monitoring, primarily due to the grains excellent thermal insulating properties. To address this issue, we propose a different approach: monitoring the equilibrium moisture content and CO2 concentration as indicators of soybean respiration within the intergranular spaces of the stored grain mass. This study propose monitoring the CO2 concentration in the intergranular air along with environmental variables for early detection of physicochemical and morphological changes in soybeans stored in vertical silos using near infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Thermogravimetry and spectrometry analyses revealed that the interrelationships among variables had a direct impact on soybean quality attributes. Specifically, the presence of soybeans with 5.2 % impurities led to an increased in respiration rates, resulting in a CO2 concentration of up to 5000 ppm and the consumption of up to 3.6 % of dry matter. Consequently, there were changes in the percentage of ash, proteins, fibers, and oils compositions. These findings highlight the potential for indirect assessments, enabling the prediction of physicochemical quality and contamination of soybeans stored in vertical silos through continuous monitoring of CO2 concentration and equilibrium moisture content.

Lipid Peroxidation in Muscle Foods: Impact on Quality, Safety and Human Health

The issue of lipid changes in muscle foods under the action of atmospheric oxygen has captured the attention of researchers for over a century. Lipid oxidative processes initiate during the slaughtering of animals and persist throughout subsequent technological processing and storage of the finished product. The oxidation of lipids in muscle foods is a phenomenon extensively deliberated in the scientific community, acknowledged as one of the pivotal factors affecting their quality, safety, and human health. This review delves into the nature of lipid oxidation in muscle foods, highlighting mechanisms of free radical initiation and the propagation of oxidative processes. Special attention is given to the natural antioxidant protective system and dietary factors influencing the stability of muscle lipids. The review traces mechanisms inhibiting oxidative processes, exploring how changes in lipid oxidative substrates, prooxidant activity, and the antioxidant protective system play a role. A critical review of the oxidative stability and safety of meat products is provided. The impact of oxidative processes on the quality of muscle foods, including flavour, aroma, taste, colour, and texture, is scrutinised. Additionally, the review monitors the effect of oxidised muscle foods on human health, particularly in relation to the autooxidation of cholesterol. Associations with coronary cardiovascular disease, brain stroke, and carcinogenesis linked to oxidative stress, and various infections are discussed. Further studies are also needed to formulate appropriate technological solutions to reduce the risk of chemical hazards caused by the initiation and development of lipid peroxidation processes in muscle foods.

Tick-borne encephalitis virus transmitted singly and in duo with Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum bacteria by ticks as pathogens modifying lipid metabolism in human blood

BACKGROUND

Ticks are vectors of various pathogens, including tick-borne encephalitis virus causing TBE and bacteria such as Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum causing e.g. viral-bacterial co-infections (TBE + LB/HGA), which pose diagnostic and therapeutic problems. Since these infections are usually accompanied by inflammation and oxidative stress causing metabolic modifications, including phospholipids, the aim of the study was to assess the level of polyunsaturated fatty acids and their metabolism (ROS- and enzyme-dependent) products in the blood plasma of patients with TBE and TBE + LB/HGA before and after pharmacotherapy.

METHODS

The total antioxidant status was determined using 2,20-azino-bis-3-ethylbenzothiazolin-6-sulfonic acid. The phospholipid and free fatty acids were analysed by gas chromatography. Lipid peroxidation was estimated by measuring small molecular weight reactive aldehyde, malondialdehyde and neuroprostanes. The reactive aldehyde was determined using gas chromatography coupled with mass spectrometry. The activity of enzymes was examined spectrophotometrically. An analysis of endocannabinoids and eicosanoids was performed using a Shimadzu UPLC system coupled with an electrospray ionization source to a Shimadzu 8060 Triple Quadrupole system. Receptor expression was measured using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The reduced antioxidant status as a result of infection was accompanied by a decrease in the level of phospholipid arachidonic acid (AA) and docosahexaenoic acid (DHA) in TBE, an increase in DHA in co-infection and in free DHA in TBE with an increase in the level of lipid peroxidation products. The enhanced activity of enzymes metabolizing phospholipids and free PUFAs increased the level of endocannabinoids and eicosanoids, while decreased 15-PGJ2 and PGE2 was accompanied by activation of granulocyte receptors before pharmacotherapy and only tending to normalize after treatment.

CONCLUSION

Since classical pharmacotherapy does not prevent disorders of phospholipid metabolism, the need to support treatment with antioxidants may be suggested.

Computational and physicochemical insight into 4-hydroxy-2-nonenal induced structural and functional perturbations in human low-density lipoprotein

Lipid peroxidation (LPO) is a biological process that frequently occurs under physiological conditions. Undue oxidative stress increases the level of LPO; which may further contribute to the development of cancer. 4-Hydroxy-2-nonenal (HNE), one of the principal by-products of LPO, is present in high concentrations in oxidatively stressed cells. HNE rapidly reacts with various biological components, including DNA and proteins; however, the extent of protein degradation by lipid electrophiles is not well understood. The influence of HNE on protein structures will likely have a considerable therapeutic value. This research elucidates the potential of HNE, one of the most researched phospholipid peroxidation products, in modifying low-density lipoprotein (LDL). In this study, we tracked the structural alterations in LDL by HNE using various physicochemical techniques. To comprehend the stability, binding mechanism and conformational dynamics of the HNE-LDL complex, computational investigations were carried out. LDL was altered in vitro by HNE, and the secondary and tertiary structural alterations were examined using spectroscopic methods, such as UV-visible, fluorescence, circular dichroism and fourier transform infrared spectroscopy. Carbonyl content, thiobarbituric acid-reactive-substance (TBARS) and nitroblue tetrazolium (NBT) reduction assays were used to examine changes in the oxidation status of LDL. Thioflavin T (ThT), 1-anilinonaphthalene-8-sulfonic (ANS) binding assay and electron microscopy were used to investigate aggregates formation. According to our research, LDL modified by HNE results in changes in structural dynamics, oxidative stress and the formation of LDL aggregates. The current investigation must characterize HNE's interactions with LDL and comprehend how it can change their physiological or pathological functions.Communicated by Ramaswamy H. Sarma.

Lipid peroxidation products' role in autophagy regulation

Autophagy, which is responsible for removing damaged molecules, prevents their accumulation in cells, thus maintaining intracellular homeostasis. It is also responsible for removing the effects of oxidative stress, so its activation takes place during increased reactive oxygen species (ROS) generation and lipid peroxidation. Therefore, the aim of this review was to summarize all the available knowledge about the effect of protein modifications by lipid peroxidation products on autophagy activation and the impact of this interaction on the functioning of cells. This review shows that reactive aldehydes (including 4-hydroxynonenal and malondialdehyde), either directly or by the formation of adducts with autophagic proteins, can activate or prevent autophagy, depending on their concentration. This effect relates not only to the initial stages of autophagy, when 4-hydroxynonenal and malondialdehyde affect the levels of proteins involved in autophagy initiation and phagophore formation, but also to the final stage, degradation, when reactive aldehydes, by binding to the active center of cathepsins, inactivate their proteolytic functions. Moreover, this review also shows how little research exists on analyzing the impact of lipid peroxidation products and their protein adducts on autophagy. Such knowledge could be used in the therapy of diseases related to autophagy disorders.

Silencing KPNA2 Promotes Ferroptosis in Laryngeal Cancer by Activating the FoxO Signaling Pathway

We aim to clarify the specific role of Karyopherin α2 (KPNA2) in the progression of laryngeal cancer, a kind of malignant tumor with a poor curative effect. We performed the bioinformatic analysis to obtain the ferroptosis-related differentially expressed genes. KPNA2 was screened out. Then the CCK-8 assay, wound healing assay, and transwell assay were used to clarify the changes in the proliferation, migration, and invasion abilities of laryngeal cancer cells after silencing KPNA2. The concentrations of iron ions, glutathione, superoxide dismutase, and malondialdehyde were evaluated by the corresponding detection kits. The expression levels of cyclooxygenase 2, Acyl-CoA synthetase long-chain family member 4, glutathione peroxidase 4, forkhead box O (FoxO)1a and FoxO3a were determined by Western Blot. A total of 45 ferroptosis-related differentially expressed genes in laryngeal cancer were obtained, and KPNA2 was selected after bioinformatic analysis. In ferroptosis-induced laryngeal cancer cells, the cell viability, migration rate, invasion ability, and the expression of glutathione peroxidase 4, glutathione, and superoxide dismutase were further decreased and the expression of cyclooxygenase 2, Acyl-CoA synthetase long-chain family member 4, iron ions, and malondialdehyde were further increased after silencing KPNA2. The expression levels of FoxO1a and FoxO3a in laryngeal cancer cells were increased by silencing KPNA2. KPNA2 may be a promising therapeutic target for laryngeal cancer. Down-regulation of KPNA2 can promote ferroptosis in laryngeal cancer by stimulating the FoxO signaling pathway.

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.

Antioxidant, aroma, and sensory characteristics of Maillard reaction products from Urechis unicinctus hydrolysates: development of food flavorings

To develop food flavorings with a delicious taste and an anti-oxidation effect, in this study, the glucose Maillard reaction was used for hydrolysates of Urechis unicinctus. The various biological activities of Maillard reaction products (MRPs) and their antioxidant capacity were evaluated. The results showed that the unique fishy odor substances of seafood in MRPs were reduced, indicating that the Maillard reaction improved the flavor of the hydrolysate of Urechis unicinctus. Meanwhile, MRPs exhibited more competitive radical scavenging activities compared to the hydrolysate. Moreover, MRPs demonstrated a considerable potential to protect against 2,2'-Azobis (2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative stress in a cell model in vitro and in a zebrafish model in vivo. Finally, a novel food flavoring was produced with MRPs as raw material, while the sensory qualities were deemed acceptable. In consequence, during industrial production, MRPs of Urechis unicinctus hydrolysate act as a high-quality raw material for functional flavorings and provide an effective way for the utilization of marine resources.

Urolithin B Attenuates Cerebral Ischemia-reperfusion Injury by Modulating Nrf2-regulated Anti-oxidation in Rats

Ischemia-reperfusion (IR) induces a wide range of irreversible injuries. Cerebral IR injury (IRI) refers to additional brain tissue damage that occurs after blood flow is restored following cerebral ischemia. Currently, no established methods exist for treating IRI. Oxidative stress is recognized as a primary mechanism initiating IRI and a crucial focal target for its treatment. Urolithin B, a metabolite derived from ellagitannins, antioxidant polyphenols, has demonstrated protective effects against oxidative stress in various disease conditions. However, the precise mechanism underlying UB's effect on IRI remains unclear. In our current investigation, we assessed UB's ability to mitigate neurological functional impairment induced by IR using a neurological deficit score. Additionally, we examined cerebral infarction following UB administration through TTC staining and neuron Nissl staining. UB's inhibition of neuronal apoptosis was demonstrated through the TUNEL assay and Caspase-3 measurement. Additionally, we examined UB's effect on oxidative stress levels by analyzing malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, and immunohistochemistry analysis of inducible nitric oxide synthase (iNOS) and 8-hydroxyl-2'-deoxyguanosine (8-OHdG). Notably, UB demonstrated a reduction in oxidative stress levels. Mechanistically, UB was found to stimulate the Nrf2/HO-1 signaling pathway, as evidenced by the significant reduction in UB's neuroprotective effects upon administration of ATRA, an Nrf2 inhibitor. In summary, UB effectively inhibits oxidative stress induced by IR through the activation of the Nrf2/HO-1 signaling pathway. These findings suggest that UB holds promise as a therapeutic agent for the treatment of IRI.

Synthesis and investigation of new indole-containing vinyl sulfide derivatives: In silico and in vitro studies for potential therapeutic applications

Indoles featuring organosulfur compounds serve as privileged structural scaffolds in various biologically active compounds. This study investigates the biological properties of five synthetic sulphenyl vinyl indoles (3 a-e) using both in silico and in vitro methods. Computational analyses employing Swiss ADME and Molinspiration software reveal the remarkable inhibitory activity of compound 3 d against proteases and kinases (scores of 0.18 and 0.06, respectively). Furthermore, it demonstrates the ability to modulate ionic and G protein-coupled receptors (scores: -0.06 and 0.31, respectively) and serves as a ligand for nuclear receptors (score 0.15). In vitro investigations highlight the compounds' efficacy in countering ABTS+ radical attacks and reducing lipid peroxidation levels. Particularly noteworthy is the superior efficacy of compounds 3 a, 3 b, and 3 e in DPPH (EC50 3 a: 268.5 μM) and TEAC assays (EC50 3 a: 49.9 μM; EC50 3 b: 133.4 μM, and EC50 3 e: 84.9 μM), as well as TBARS levels. Compound 3 c significantly reduces acetylcholinesterase activity, positioning itself as a noteworthy enzyme inhibitor. This study emphasizes the versatile biological potential of synthetic indole derivatives, suggesting their applicability for therapeutic purposes.

Reactive oxygen species in biological systems: Pathways, associated diseases, and potential inhibitors-A review

Reactive oxygen species (ROS) are produced under normal physiological conditions and may have beneficial and harmful effects on biological systems. ROS are involved in many physiological processes such as differentiation, proliferation, necrosis, autophagy, and apoptosis by acting as signaling molecules or regulators of transcription factors. In this case, maintaining proper cellular ROS levels is known as redox homeostasis. Oxidative stress occurs because of the imbalance between the production of ROS and antioxidant defenses. Sources of ROS include the mitochondria, auto-oxidation of glucose, and enzymatic pathways such as nicotinamide adenine dinucleotide phosphate reduced (NAD[P]H) oxidase. The possible ROS pathways are NF-κB, MAPKs, PI3K-Akt, and the Keap1-Nrf2-ARE signaling pathway. This review covers the literature pertaining to the possible ROS pathways and strategies to inhibit them. Additionally, this review summarizes the literature related to finding ROS inhibitors.

Lipid Peroxidation Drives Liquid-Liquid Phase Separation and Disrupts Raft Protein Partitioning in Biological Membranes

The peroxidation of membrane lipids by free radicals contributes to aging, numerous diseases, and ferroptosis, an iron-dependent form of cell death. Peroxidation changes the structure and physicochemical properties of lipids, leading to bilayer thinning, altered fluidity, and increased permeability of membranes in model systems. Whether and how lipid peroxidation impacts the lateral organization of proteins and lipids in biological membranes, however, remains poorly understood. Here, we employ cell-derived giant plasma membrane vesicles (GPMVs) as a model to investigate the impact of lipid peroxidation on ordered membrane domains, often termed membrane rafts. We show that lipid peroxidation induced by the Fenton reaction dramatically enhances the phase separation propensity of GPMVs into coexisting liquid-ordered (Lo) and liquid-disordered (Ld) domains and increases the relative abundance of the disordered phase. Peroxidation also leads to preferential accumulation of peroxidized lipids and 4-hydroxynonenal (4-HNE) adducts in the disordered phase, decreased lipid packing in both Lo and Ld domains, and translocation of multiple classes of raft proteins out of ordered domains. These findings indicate that the peroxidation of plasma membrane lipids disturbs many aspects of membrane rafts, including their stability, abundance, packing, and protein and lipid composition. We propose that these disruptions contribute to the pathological consequences of lipid peroxidation during aging and disease and thus serve as potential targets for therapeutic intervention.

Evaluation of systemic oxidative stress in patients with melasma

BACKGROUND

The significance of oxidative stress has been assessed and proven in the etiopathogenesis of many cutaneous disorders, but there are few studies that evaluated the role of only some factors involved in oxidative stress in patients with melasma.

OBJECTIVE

This study aimed to examine the role of oxidative stress in melasma and assess the relationship between systemic oxidative stress and the severity and extension of this disease.

METHODS

In this study, the serum levels of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), malondialdehyde (MDA), protein carbonyl (PC), selenium (Se), vitamin E (vit E), and vitamin C (vit C) of fifty patients with melasma were compared with those of fifty controls.

RESULTS

The serum level of MDA was significantly higher in the melasma group (3.08 vs. 2.35 U/mL; p < 0.05), and it was positively correlated with the severity (r = 0.4; p < 0.001) and extension (r = 0.3; p < 0.05) of the disease. Furthermore, the serum level of vit C was significantly lower in melasma patients (2.16 vs. 2.57 μg/mL; p < 0.001).

CONCLUSION

Systemic oxidative stress has a key role in the etiopathogenesis of melasma. Serum concentrations of MDA and vitamin C are indicators of this impairment.

Malondialdehyde and TNF-α lowering effects of purified gambier (Uncaria gambir Roxb.) in diabetic rats

BACKGROUND

Malondialdehyde (MDA) is one of a dominat marker in oxidative stress condition, and when inflammation occurred tumor necrosis factor- α (TNF-α) played a significant influence in the propagation this process. Purified gambier (Uncaria gambier Roxb.) contained 90% catechin which is proven to have antioxidant activity and may prevent unwanted inflammatory responses during diabetic state.

OBJECTIVE

The objective of this research was to assess how purified gambier affected plasma MDA and TNF- α levels in alloxan-induced diabetic rats.

MATERIAL AND METHODS

In this study, 35 rats were used. Alloxan 120 mg/kg BW intraperitoneal injection was administered to induce diabetes conditions in rats. All animals were divided into 5 groups, diabetic control group treated with vehicle, positive control group treated with glibenclamide dose 0.45 mg/kg BW), and treatment groups treated with purified gambier dose of 2.5; 5 and 10 mg/kg BW. All animals were treated respectively for 14 days. Plasma MDA and TNF- α levels were measured on day 3, and 14.

RESULTS

Two-way ANOVA was applied to analyze all of the data, these findings suggested that purified gambier has antioxidant-related anti-inflammation actions. possesses blood sugar-lowering activity (p<0.05). The plasma MDA and TNF- α level of treatment group were significantly reduced (p<0.05) compared to diabetes control group.

CONCLUSION

These results depicted that at doses of 2.5-10 mg/kg BW, purified gambier has antioxidant-associated anti-inflammation effects when given for 14 days on diabetic rat model by reducing plasma levels MDA and TNF-α.

Lipid peroxidation: Reactive carbonyl species, protein/DNA adducts, and signaling switches in oxidative stress and cancer

Under the exposure of lipids to reactive oxygen species (ROS), lipid peroxidation proceeds non-enzymatically and generates an extremely heterogeneous mixture of reactive carbonyl species (RCS). Among them, HNE, HHE, MDA, methylglyoxal, glyoxal, and acrolein are the most studied and/or abundant ones. Over the last decades, significant progress has been achieved in understanding mechanisms of RCS generation, protein/DNA adduct formation, and their identification and quantification in biological samples. In our review, we critically discuss the advancements in understanding the roles of RCS-induced protein/DNA modifications in signaling switches to provide adaptive cell response under physiological and oxidative stress conditions. At non-toxic concentrations, RCS modify susceptible Cys residue in c-Src to activate MAPK signaling and Cys, Lys, and His residues in PTEN to cause its reversible inactivation, thereby stimulating PI3K/PKB(Akt) pathway. RCS toxic concentrations cause irreversible Cys modifications in Keap1 and IKKβ followed by stabilization of Nrf2 and activation of NF-κB, respectively, for their nuclear translocation and antioxidant gene expression. Dysregulation of these mechanisms causes diseases including cancer. Alterations in RCS, RCS detoxifying enzymes, RCS-modified protein/DNA adducts, and signaling pathways have been implicated in various cancer types.

Antioxidant, anti-inflammatory, and anti-apoptotic effects of genkwanin against aflatoxin B1-induced testicular toxicity

Aflatoxin B1 (AFB1) is the most hazardous aflatoxin that causes significant damage to the male reproductive system. Genkwanin (GNK) is a bioactive flavonoid that shows antioxidant and anti-inflammatory potential. Therefore, the current study was planned to evaluate the effects of GNK against AFB1-induced testicular toxicity. Forty-eight male rats were distributed into four groups (n = 12 rats). AFB1 (50 μg/kg) and GNK (20 mg/kg) were administered to the rats for eight weeks. Results of the current study revealed that AFB1 exposure induced adverse effects on the Nrf2/Keap1 pathway and reduced the expressions and activities of antioxidant enzymes. Additionally, it increased the levels of oxidative stress markers. Furthermore, expressions of steroidogenic enzymes were down-regulated by AFB1 intoxication. Besides, AFB1 exposure reduced the levels of gonadotropins and plasma testosterone, which subsequently reduced the epididymal sperm count, motility, and hypo-osmotic swelled (HOS) sperms, while increasing the number of dead sperms and causing morphological anomalies of the head, midpiece, and tail of the sperms. In addition, AFB1 decreased the activities of testicular function marker enzymes and the levels of inflammatory markers. Moreover, it severely affected the apoptotic profile by up-regulating the expressions of Bax and Casp3, while down-regulating the Bcl2 expression. Besides, AFB1 significantly damaged the histoarchitecture of testicular tissues. However, GNK treatment reversed all the AFB1-induced damages in the rats. Taken together, the current study reports the potential use of GNK as a therapeutic agent to prevent AFB1-induced testicular toxicity due to its antioxidant, anti-inflammatory, and anti-apoptotic properties.

Collagen-EGCG Combination Synergistically Prevents UVB-Induced Skin Photoaging in Nude Mice

Ultraviolet (UV) radiation is a major cause of skin photoaging through generating excessive oxidative stress and inflammation. One of the strategies is to use photo-chemoprotectors, such as natural products with antioxidant and anti-inflammatory properties, to protect the skin from photo damage. The present study investigates the photoprotective potentials of topical administration of unhydrolyzed collagen, epigallocatechin gallate (EGCG), and their combination against ultraviolet B (UVB)-induced photoaging in nude mice. It is found that both the solo and combined pretreatments could recover UVB-induced depletion of antioxidative enzymes, including superoxide dismutase and glutathione peroxidase (GSH-Px), as well as an increase of lipid peroxide malondialdehyde and inflammatory tumor necrosis factor-α. Meanwhile, the UVB-stimulated skin collagen degradation is attenuated significantly with drug treatments, which is evidenced by expression analysis of matrix metalloproteinase-1 and hydroxyproline. Additionally, the mouse skin histology shows that the drug-pretreated groups possess decreased epidermis thickness and normal collagen fiber structure of the dermis layer. These results demonstrate that both EGCG and collagen can protect the skin against UVB-induced skin photoaging. Synergistically, the combination of them shows the maximum prevention to skin damage, showing its potential in the application of anti-photoaging formulation products.

The Anti-Inflammatory Action of Cannabigerol Accompanied by the Antioxidant Effect of 3-O-ethyl Ascorbic Acid in UVA-Irradiated Human Keratinocytes

Excessive daily exposure of human skin to natural UVA radiation leads to impaired redox homeostasis in epidermal keratinocytes, resulting in changes in their proteome. Commonly used antioxidants usually exhibit protection in a narrowed range, which makes it necessary to combine their effects. Therefore, the aim of this study was to analyze the protective effect of cannabigerol (CBG) and 3-O-ethyl ascorbic acid (EAA), used separately and together, on the proteomic profile of UVA irradiated keratinocytes. Proteomic analysis with the use of the Q Exactive HF mass spectrometer, combined with biostatistic tests, performed on UVA-irradiated keratinocytes indicated enhanced and lowered expression of 186 and 160 proteins, respectively. CBG treatment after UVA irradiation reduced these numbers to 110 upregulated and 49 downregulated proteins, while EAA eliminated all these changes. CBG completely eliminated the UV-induced effect on the expression of pro-inflammatory proteins and significantly increased the level of proteins responsible for cellular locomotion. On the other hand, CBG reduced the level of UVA-induced 4-hydroxynonenal protein adducts fivefold, whereas EAA had no effect on this modification. At the same time, CBG and EAA did not modify the expression/structure of proteins in relation to the nonirradiated control keratinocytes in the case of an unaccompanied use or slightly modified the protein profile when used in a mixture. The combined protective effects of CBG on protein structure and EAA on protein expression profile allowed us to obtain a wider protection of cells against UVA radiation, compared with when the compounds were used alone. SIGNIFICANCE STATEMENT: Proteomic analysis of human skin cells allows to conclude that 3-O-ethyl ascorbic acid eliminates UVA-induced changes in the expression of keratinocyte proteins, while cannabigerol significantly reduces 4-hydroxynonenal protein adducts. The combined protective effects of cannabigerol on protein structure and of 3-O-ethyl ascorbic acid on protein expression profile allowed to obtain a wider protection of cells against UVA radiation.

Transcriptomic analysis of the antioxidant responses and immunomodulatory effects of dietary melatonin in red swamp crayfish (Procambarus clarkii)

This study aimed to investigate the effects of dietary melatonin (MT) levels on the antioxidant capacity, immunomodulatory, and transcriptional regulation of red swamp crayfish. Six experimental diets with different levels of MT (0, 22.5, 41.2, 82.7, 165.1, and 329.2 mg/kg diet) were fed to juvenile crayfish for 60 d. The transcriptome data of the control group and the group supplemented with dietary MT at 165.1 mg/kg were obtained using RNA-seq. In total, 3653 differentially expressed genes (2082 up-regulated and 1571 down-regulated) were identified. Pathways and genes related to antioxidant immune and growth performance were verified by qRT-PCR. The total hemocyte count, phagocytosis rate, and respiratory burst were significantly increased in the MT (165.1 mg/kg) group compared to the control group. Analysis of antioxidant immune-related enzymes in the hepatopancreas demonstrated that dietary MT (165.1 mg/kg) significantly increased activities of catalase, superoxide dismutase, glutathione reductase, and glutathione peroxidase and significantly decreased aspartate aminotransferase and alanine aminotransferase activity. At the transcriptional level, dietary MT up-regulated expression levels of genes associated with antioxidant immune and development, which included toll-like receptors, Crustin, C-type lectin, and so on. To conclude, MT could be used as a supplement in crayfish feed to increase immunity and antioxidant capacity and according to the broken line regression, the ideal MT concentration was the 159.02 mg/kg. Overall, this study demonstrates the role of melatonin in the antioxidant responses and immunomodulatory of Procambarus clarkii, laying the foundation for the development of melatonin as a feed additive in the aquaculture of this species.

Exosomal noncoding RNA-mediated spatiotemporal regulation of lipid metabolism: Implications in immune evasion and chronic inflammation

The hallmark of chronic inflammatory diseases is immune evasion. Successful immune evasion involves numerous mechanisms to suppress both adaptive and innate immune responses. Either direct contact between cells or paracrine signaling triggers these responses. Exosomes are critical drivers of these interactions and exhibit both immunogenic and immune evasion properties during the development and progression of various chronic inflammatory diseases. Exosomes carry diverse molecular cargo, including lipids, proteins, and RNAs that are crucial for immunomodulation. Moreover, recent studies have revealed that exosomes and their cargo-loaded molecules are extensively involved in lipid remodeling and metabolism during immune surveillance and disease. Many studies have also shown the involvement of lipids in controlling immune cell activities and their crucial upstream functions in regulating inflammasome activation, suggesting that any perturbation in lipid metabolism results in abnormal immune responses. Strikingly, the expanded immunometabolic reprogramming capacities of exosomes and their contents provided insights into the novel mechanisms behind the prophylaxis of inflammatory diseases. By summarizing the tremendous therapeutic potential of exosomes, this review emphasizes the role of exosome-derived noncoding RNAs in regulating immune responses through the modulation of lipid metabolism and their promising therapeutic applications.

Altered Lipid Moieties and Carbonyls in a Wistar Rat Dietary Model of Subclinical Fatty Liver: Potential Sex-Specific Biomarkers of Early Fatty Liver Disease?

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat builds up in the liver. To date, there is a lack of knowledge about the subtype of lipid structures affected in the early stages of NAFLD. The aim of this study was to analyze serum and liver lipid moieties, specifically unsaturations and carbonyls, by nuclear magnetic resonance (NMR) in a subclinical Wistar rat model of NAFLD for detecting early alterations and potential sex dimorphisms. Twelve weeks of a high-fat diet (HFD) induced fat accumulation in the liver to a similar extent in male and female Wistar rats. In addition to total liver fat accumulation, Wistar rats showed a shift in lipid subtype composition. HFD rats displayed increased lipid carbonyls in both liver and serum, and decreased in unsaturated fatty acids (UFAs) and polyunsaturated fatty acids (PUFAs), with a much stronger effect in male than female animals. Our results revealed that the change in fat was not only quantitative but also qualitative, with dramatic shifts in relevant lipid structures. Finally, we compared the results found in Wistar rats with an analysis in a human patient cohort of extreme obesity. For the first time to our knowledge, lipid carbonyl levels and lipoproteins profiles were analyzed in the context of subclinical NAFLD. The association found between lipid carbonyls and alanine aminotransferase (ALT) in a human cohort of extremely obese individuals further supports the potential role of lipid moieties as biomarkers of early NAFLD.

Short Survey on the Protein Modifications in Plasma during SARS-CoV-2 Infection

Although the COVID-19 pandemic has ended, it is important to understand the pathology of severe SARS-CoV-2 infection associated with respiratory failure and high mortality. The plasma proteome, including protein modification by lipid peroxidation products in COVID-19 survivors (COVID-19; n = 10) and deceased individuals (CovDeath; n = 10) was compared in samples collected upon admission to the hospital, when there was no difference in their status, with that of healthy individuals (Ctr; n = 10). The obtained results show that COVID-19 development strongly alters the expression of proteins involved in the regulation of exocytosis and platelet degranulation (top 20 altered proteins indicated by analysis of variance; p-value (False Discovery Rate) cutoff at 5%). These changes were most pronounced in the CovDeath group. In addition, the levels of 4-hydroxynonenal (4-HNE) adducts increased 2- and 3-fold, whereas malondialdehyde (MDA) adducts increased 7- and 2.5-fold, respectively, in COVID-19 and CovDeath groups. Kinases and proinflammatory proteins were particularly affected by these modifications. Protein adducts with 15-deoxy-12,14-prostaglandin J2 (15d-PGJ2) were increased 2.5-fold in COVID-19 patients, including modifications of proteins such as p53 and STAT3, whereas CovDeath showed a decrease of approximately 60% compared with Ctr. This study for the first time demonstrates the formation of lipid metabolism products-protein adducts in plasma from survived and deceased COVID-19 patients, significantly distinguishing them, which may be a predictor of the course of SARS-CoV-2 infection.

Lipid peroxidation drives liquid-liquid phase separation and disrupts raft protein partitioning in biological membranes

The peroxidation of membrane lipids by free radicals contributes to aging, numerous diseases, and ferroptosis, an iron-dependent form of cell death. Peroxidation changes the structure, conformation and physicochemical properties of lipids, leading to major membrane alterations including bilayer thinning, altered fluidity, and increased permeability. Whether and how lipid peroxidation impacts the lateral organization of proteins and lipids in biological membranes, however, remains poorly understood. Here, we employ cell-derived giant plasma membrane vesicles (GPMVs) as a model to investigate the impact of lipid peroxidation on ordered membrane domains, often termed membrane rafts. We show that lipid peroxidation induced by the Fenton reaction dramatically enhances phase separation propensity of GPMVs into co-existing liquid ordered (raft) and liquid disordered (non-raft) domains and increases the relative abundance of the disordered, non-raft phase. Peroxidation also leads to preferential accumulation of peroxidized lipids and 4-hydroxynonenal (4-HNE) adducts in the disordered phase, decreased lipid packing in both raft and non-raft domains, and translocation of multiple classes of proteins out of rafts. These findings indicate that peroxidation of plasma membrane lipids disturbs many aspects of membrane rafts, including their stability, abundance, packing, and protein and lipid composition. We propose that these disruptions contribute to the pathological consequences of lipid peroxidation during aging and disease, and thus serve as potential targets for therapeutic intervention.

Changes in Ion Transport across Biological Membranes Exposed to Particulate Matter

The cells of living organisms are surrounded by the biological membranes that form a barrier between the internal and external environment of the cells. Cell membranes serve as barriers and gatekeepers. They protect cells against the entry of undesirable substances and are the first line of interaction with foreign particles. Therefore, it is very important to understand how substances such as particulate matter (PM) interact with cell membranes. To investigate the effect of PM on the electrical properties of biological membranes, a series of experiments using a black lipid membrane (BLM) technique were performed. L-α-Phosphatidylcholine from soybean (azolectin) was used to create lipid bilayers. PM samples of different diameters (<4 (SRM-PM4.0) and <10 μm (SRM-PM10) were purchased from The National Institute of Standards and Technology (USA) to ensure the repeatability of the measurements. Lipid membranes with incorporated gramicidin A (5 pg/mL) ion channels were used to investigate the effect of PM on ion transport. The ionic current passing through the azolectin membranes was measured in ionic gradients (50/150 mM KCl on cis/trans side). In parallel, the electric membrane capacitance measurements, analysis of the conductance and reversal potential were performed. Our results have shown that PM at concentration range from 10 to 150 μg/mL reduced the basal ionic current at negative potentials while increased it at positive ones, indicating the interaction between lipids forming the membrane and PM. Additionally, PM decreased the gramicidin A channel activity. At the same time, the amplitude of channel openings as well as single channel conductance and reversal potential remained unchanged. Lastly, particulate matter at a concentration of 150 μg/mL did not affect the electric membrane capacity to any significant extent. Understanding the interaction between PM and biological membranes could aid in the search for effective cytoprotective strategies. Perhaps, by the use of an artificial system, we will learn to support the consequences of PM-induced damage.

Lipid Peroxidation and Antioxidant Protection

Lipid peroxidation (LP) is the most important type of oxidative-radical damage in biological systems, owing to its interplay with ferroptosis and to its role in secondary damage to other biomolecules, such as proteins. The chemistry of LP and its biological consequences are reviewed with focus on the kinetics of the various processes, which helps understand the mechanisms and efficacy of antioxidant strategies. The main types of antioxidants are discussed in terms of structure-activity rationalization, with focus on mechanism and kinetics, as well as on their potential role in modulating ferroptosis. Phenols, pyri(mi)dinols, antioxidants based on heavy chalcogens (Se and Te), diarylamines, ascorbate and others are addressed, along with the latest unconventional antioxidant strategies based on the double-sided role of the superoxide/hydroperoxyl radical system.

Cannabidiol and Cannabigerol Modify the Composition and Physicochemical Properties of Keratinocyte Membranes Exposed to UVA

The action of UVA radiation (both that derived from solar radiation and that used in the treatment of skin diseases) modifies the function and composition of keratinocyte membranes. Therefore, this study aimed to assess the effects of phytocannabinoids (CBD and CBG), used singly and in combination, on the contents of phospholipids, ceramides, lipid rafts and sialic acid in keratinocyte membranes exposed to UVA radiation, together with their structure and functionality. The phytocannabinoids, especially in combination (CBD+CBG), partially prevented increased levels of phosphatidylinositols and sialic acid from occurring and sphingomyelinase activity after the UVA exposure of keratinocytes. This was accompanied by a reduction in the formation of lipid rafts and malondialdehyde, which correlated with the parameters responsible for the integrity and functionality of the keratinocyte membrane (membrane fluidity and permeability and the activity of transmembrane transporters), compared to UVA-irradiated cells. This suggests that the simultaneous use of two phytocannabinoids may have a protective effect on healthy cells, without significantly reducing the therapeutic effect of UV radiation used to treat skin diseases such as psoriasis.

Elevated phospholipid hydroperoxide glutathione peroxidase (GPX4) expression modulates oxylipin formation and inhibits age-related skeletal muscle atrophy and weakness

Our previous studies support a key role for mitochondrial lipid hydroperoxides as important contributors to denervation-related muscle atrophy, including muscle atrophy associated with aging. Phospholipid hydroperoxide glutathione peroxidase 4 (GPX4) is an essential antioxidant enzyme that directly reduces phospholipid hydroperoxides and we previously reported that denervation-induced muscle atrophy is blunted in a mouse model of GPX4 overexpression. Therefore, the goal of the present study was to determine whether GPX4 overexpression can reduce the age-related increase in mitochondrial hydroperoxides in skeletal muscle and ameliorate age-related muscle atrophy and weakness (sarcopenia). Male C57Bl6 WT and GPX4 transgenic (GPX4Tg) mice were studied at 3 to 5 and 23-29 months of age. Basal mitochondrial peroxide generation was reduced by 34% in muscle fibers from aged GPX4Tg compared to old WT mice. GPX4 overexpression also reduced levels of lipid peroxidation products: 4-HNE, MDA, and LOOHs by 38%, 32%, and 84% respectively in aged GPX4Tg mice compared to aged WT mice. Muscle mass was preserved in old GPX4 Tg mice by 11% and specific force generation was 21% higher in old GPX4Tg versus age matched male WT mice. Oxylipins from lipoxygenases (LOX) and cyclooxygenase (COX), as well as less abundant non-enzymatically generated isomers, were significantly reduced by GPX4 overexpression. The expression of cPLA2, 12/15-LOX and COX-2 were 1.9-, 10.5- and 3.4-fold greater in old versus young WT muscle respectively, and 12/15-LOX and COX-2 levels were reduced by 37% and 35%, respectively in muscle from old GPX4Tg mice. Our study suggests that lipid peroxidation products may play an important role in the development of sarcopenia, and their detoxification might be an effective intervention in preventing muscle atrophy.

Dietary effect of grape (Vitis vinifera) seed extract mitigates hepatic disorders caused by oxidized fish oil in rainbow trout (Oncorhynchus mykiss)

The major goal of this study was to determine the effect of grape seed extract (GSE) on liver damage in rainbow trout (Oncorhynchus mykiss) that was caused by the consumption of dietary oxidized fish oil (OFO). Rainbow trout were fed six different experimental diets coded OX-GSE 0 (OFO diet), OX-GSE 1 (OFO and 0.1% GSE), OX-GSE 3 (OFO and 0.3% GSE), GSE 0 (fresh fish oil and 0.0% GSE), GSE 1 (fresh fish oil and 0.1% GSE), and GSE 3 (fresh fish oil and 0.3% GSE) for 30 days. The lowest % hepatosomatic index (HSI) result was calculated in fish fed with OX-GSE 0 and the highest HSI was determined in fish fed with GSE 1 diets (p < 0.05). Histopathologically, hydropic degeneration in hepatocytes significantly increased OX-GSE 0 and GSE 3 compared to GSE 1 diets (p < 0.05). Deposition of lipid droplets in hepatocytes was significantly increased in OX-GSE 0 and OX-GSE 3 groups than others (p < 0.05). Liver biochemistry parameters such as superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) were significantly affected by OX and GSE treatments (p < 0.05). There were significant differences in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) among the liver enzymes analyzed in serum in OX and GSE (p < 0.05), meanwhile no difference was observed in lactate dehydrogenase (LDH) values between groups (p > 0.05). In conclusion, liver biochemistry and histopathology of rainbow trout consuming diets containing oxidized fish oil were negatively affected. However, it was determined that the supplementation of 0.1% GSE to the diet had a significant ameliorative role in these adverse effects.

Artemisinin and Ambrosia trifida extract aggravate the effects of short freeze-thaw stress in winter rye (Secale cereale) seedlings

The freeze-thaw and allelopathy from alien giant ragweed (Ambrosia trifida L.) and artemisinin have led to a serious stress to plants, influencing the agricultural quality and crop yield in north-east China. Yet, little is known how allelopathy affect plants under the freeze-thaw process. In this study, the characteristics in winter rye (Secale cereale L.) seedlings were investigated by laboratory simulation. The results showed that during the freezing process, application of artemisinin and A. trifida extract significantly increased the soluble protein content and accelerated lipid peroxidation, while they significantly inhibited antioxidant enzymes, photosynthesis and respiration (P <0.05). During the thawing process, the freezing pressure decreased, and activities of antioxidant enzymes were significantly improved to mitigate artemisinin and A. trifida extract induced stress (P <0.05). In addition, the sensitivity of the investigated metabolic processes in winter rye seedlings were highest to artemisinin and A. trifida extract in the freezing process. This study suggested that the stress response induced by artemisinin and A. trifida extract on winter rye seedlings in the freezing process was greater than that in the thawing process.

Melatonin Alleviates Retinal Ischemia-Reperfusion Injury by Inhibiting p53-Mediated Ferroptosis

Retinal ischemia-reperfusion (RIR) injury caused by high intraocular pressure (IOP) is an important risk factor contributing to retinal ganglion cell (RGC) death, eventually causing blindness. A key progressive pathological process in the development of RIR is the death of RGCs. However, the detailed mechanisms underlying RGC death caused by RIR have not yet been clearly elucidated, and effective treatments are lacking. Ferroptosis is a recently defined form of programmed cell death that is closely related to organ injury. Melatonin (MT) is a promising neuroprotective agent, but its effects on RIR injury remain unclear. In this study, murine models of acute ocular hypertension and oxygen and glucose deprivation/reoxygenation (OGD/R) model were adopted to simulate retinal ischemia. MT alleviated retinal damage and RGC death in RIR mice, significantly attenuating RIR-induced ferroptosis. Furthermore, MT reduced the expression of p53, a master regulator of ferroptosis pathways, and the upregulation of p53 promoted ferroptosis and largely abolished the neuroprotective effects of MT. Mechanistically, the overexpression (OE) of p53 suppressed the expression of the solute carrier family 7 member 11 (Slc7a11), which was accompanied by increased 12-lipoxygenase (Alox12) expression, triggering retinal ferroptosis. Moreover, MT-ameliorated apoptosis, neuroinflammation and microglial activation were observed. In summary, MT conferred neuroprotection against RIR injury by inhibiting p53-mediated ferroptosis. These findings indicate that MT is a retina-specific ferroptosis inhibitor and a promising therapeutic agent for retinal neuroprotection.

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.

Methanol promotes the biodegradation of 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB 180) by the microbial consortium QY2: Metabolic pathways, toxicity evaluation and community response

As one of the most frequently detected PCB congeners in human adipose tissue, 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB 180) has attracted much attention. However, PCB 180 is difficult to be directly utilized by microorganisms due to its hydrophobicity and obstinacy. Herein, methanol (5 mM) as a co-metabolic carbon source significantly stimulated the degradation performance of microbial consortium QY2 for PCB 180 (51.9% higher than that without methanol addition). Six metabolic products including low-chlorinated PCBs and chlorobenzoic acid were identified during co-metabolic degradation, denoting that PCB 180 was metabolized via dechlorination, hydroxylation and ring-opening pathways. The oxidative stress and apoptosis induced by PCB 180 were dose-dependent, but the addition of methanol effectively promoted the tolerance of consortium QY2 to resist unfavorable environmental stress. Additionally, the significant reduction of intracellular reactive oxygen species (ROS) and enhancement of cell viability during methanol co-metabolic degradation proved that the degradation was a detoxification process. The microbial community and network analyses suggested that the potential PCB 180 degrading bacteria in the community (e.g., Achromobacter, Cupriavidus, Methylobacterium and Sphingomonas) and functional abundance of metabolic pathways were selectively enriched by methanol, and the synergies among species whose richness increased after methanol addition might dominate the degradation process. These findings provide new insights into the biodegradation of PCB 180 by microbial consortium.

Bidirectionally Regulating Viral and Cellular Ferroptosis with Metastable Iron Sulfide Against Influenza Virus

Influenza virus with numerous subtypes and frequent variation limits the development of high-efficacy and broad-spectrum antiviral strategy. Here, a novel multi-antiviral metastable iron sulfides (mFeS) against various influenza A/B subtype viruses is developed. This work finds that mFeS induces high levels of lipid peroxidation and •OH free radicals in the conservative viral envelope, which depends on Fe²⁺ . This phenomenon, termed as a viral ferroptosis, results in the loss of viral infectibility and pathogenicity in vitro and in vivo, respectively. Furthermore, the decoction of mFeS (Dc(mFeS)) inhibits cellular ferroptosis-dependent intracellular viral replication by correcting the virus-induced reprogrammed sulfur metabolism, a conserved cellular metabolism. Notably, personal protective equipment (PPE) that is loaded with mFeS provides good antiviral protection. Aerosol administration of mFeS combined with the decoction (mFeS&Dc) has a potential therapeutic effect against H1N1 lethal infection in mice. Collectively, mFeS represents an antiviral alternative with broad-spectrum activity against intracellular and extracellular influenza virus.

Protective effects of an anti-4-HNE monoclonal antibody against liver injury and lethality of endotoxemia in mice

4-hydroxy-2-nonenal (4-HNE) is a lipid peroxidation product that is known to be elevated during oxidative stress. During systemic inflammation and endotoxemia, plasma levels of 4-HNE are elevated in response to lipopolysaccharide (LPS) stimulation. 4-HNE is a highly reactive molecule due to its generation of both Schiff bases and Michael adducts with proteins, which may result in modulation of inflammatory signaling pathways. In this study, we report the production of a 4-HNE adduct-specific monoclonal antibody (mAb) and the effectiveness of the intravenous injection of this mAb (1 mg/kg) in ameliorating LPS (10 mg/kg, i.v.)-induced endotoxemia and liver injury in mice. Endotoxic lethality in control mAb-treated group was suppressed by the administration of anti-4-HNE mAb (75 vs. 27%). After LPS injection, we observed a significant increase in the plasma levels of AST, ALT, IL-6, TNF-α and MCP-1, and elevated expressions of IL-6, IL-10 and TNF-α in the liver. All these elevations were inhibited by anti-4-HNE mAb treatment. As to the underlining mechanism, anti-4-HNE mAb inhibited the elevation of plasma high mobility group box-1 (HMGB1) levels, the translocation and release of HMGB1 in the liver and the formation of 4-HNE adducts themselves, suggesting a functional role of extracellular 4-HNE adducts in hypercytokinemia and liver injury associated with HMGB1 mobilization. In summary, this study reveals a novel therapeutic application of anti-4-HNE mAb for endotoxemia.

Insights into the promising prospect of medicinal chemistry studies against neurodegenerative disorders

Medicinal chemistry is an interdisciplinary field that incorporates organic chemistry, biochemistry, physical chemistry, pharmacology, informatics, molecular biology, structural biology, cell biology, and other disciplines. Additionally, it considers molecular factors such as the mode of action of the drugs, their chemical structure-activity relationship (SAR), and pharmacokinetic aspects like absorption, distribution, metabolism, elimination, and toxicity. Neurodegenerative disorders (NDs), which are defined by the breakdown of neurons over time, are affecting an increasing number of people. Oxidative stress, particularly the increased production of Reactive Oxygen Species (ROS), plays a crucial role in the growth of various disorders, as indicated by the identification of protein, lipid, and Deoxyribonucleic acid (DNA) oxidation products in vivo. Because of their inherent nature, most biological molecules are vulnerable to ROS, even if they play a role in metabolic parameters and cell signaling. Due to their high polyunsaturated fatty acid content, low antioxidant barrier, and high oxygen uptake, neurons are particularly vulnerable to oxidation by nature. As a result, excessive ROS generation in neurons looks especially harmful, and the mechanisms associated with biomolecule oxidative destruction are several and complex. This review focuses on the formation and management of ROS, as well as their chemical characteristics (both thermodynamic and kinetic), interactions, and implications in NDs.

Natural Melanogenesis Inhibitor, Antioxidant, and Collagen Biosynthesis Stimulator of Phytochemicals in Rice Bran and Husk Extracts from Purple Glutinous Rice (Oryza sativa L. cv. Pieisu 1 CMU) for Cosmetic Application

Oryza sativa L. cv. Pieisu 1 CMU (PES1CMU) has a high anthocyanin content in the colored bran and high phenolic content in the husk. Biologically active compounds in plants are available as dietary supplements and cosmetics. To expand the utilization of natural resources, PES1CMU will be a natural remedy for skin hyperpigmentation and aging. Cell-free tyrosinase inhibition and scavenging assays were used to screen all extracts, including PES1CMU-rice bran oil (RBO), PES1CMU-defatted rice bran (DFRB), and PES1CMU-husk (H). PES1CMU extracts were first examined in IBMX-stimulated B16 cells and H₂O₂-induced fibroblasts. The results exhibited that PES1CMU-DFRB was the most effective inhibitor of mushroom tyrosinase, intracellular melanin production (fold change of 1.11 ± 0.01), and tyrosinase activity (fold change of 1.22 ± 0.10) in IBMX-stimulated B16 cells. Particularly, PES1CMU-DFRB showed a comparable whitening effect to the standard arbutin with no significant difference (p > 0.05). Moreover, PES1CMU-DFRB and PES1CMU-H demonstrated strong scavenging activities. After accelerated cell aging caused by H₂O₂ exposure in fibroblasts, the levels of malondialdehyde production in all PES1CMU-treated fibroblasts were comparable with those of standard l-ascorbic acid (p > 0.05). Besides, PES1CMU-DFRB and PES1CMU-H treatment significantly inhibited collagen degradation against MMP-2 compared to l-ascorbic acid-treated cells (p > 0.05). PES1CMU rice-processing wastes (DFRB and H) could become potential natural sources for dermatocosmetic constituents in skin anti-aging and whitening products.

Functionalization of ampicillin and gentamicin with biogenic copper nanoparticles (CuNPs) remodel antimicrobial and cytotoxic outcome against MDR clinical isolates

The present study reports the functionalization of antibiotic-conjugated Alternanthera pungens and Trichodesma indicum copper nanoparticles (CuNPs). Initially, antibiotic profiling of multi-drug resistant (MDR) clinical isolates against five antibiotics was verified and then gentamicin and ampicillin conjugates of CuNPs were prepared. Biosynthesized nanostructures were characterized through UV-visible spectroscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction and scanning electron microscope. Biogenic synthesized CuNPs displayed highest antibacterial activity (24.0-31.3 mm inhibition zones) when capped with gentamicin as compared to the ampicillin-conjugated NPs which showed resistance against most of the bacterial species. A. pungens-derived conjugates of gentamicin (CuAp-GNT) along with the vehicle revealed 4.86 ± 0.20% and 4.25 ± 2.96% hemolytic potential and highest MDA production in S. typhimurium (3.18 ± 1.52 µg/mL and 6.31 ± 3.49 µg/mL) and K. pneumoniae (2.99 ± 0.90 µg/mL and 4.06 ± 1.20 µg/mL). Similarly, CuAp-GNT also showed highest DNA protection ability by displaying 1342.99 ± 11.87 band intensity. All-inclusive, CuAp showed more promising effects when conjugated with gentamicin indicating that capping of gentamicin with the active components of the plant-based copper nanostructures increases the antibacterial capacity of the drug. Hence, conjugation of antibiotics with bio-based sources offers great potential for identifying potent drug leads.

Blue light-induced lipid oxidation and the antioxidant property of hypotaurine: evaluation via measuring ultraweak photon emission

The effects of blue light on human body have attracted attention. The human skin in contact with the outside environment is often exposed to blue light, and the effects of this exposure remain to be fully determined. Therefore, in this study, we investigated the effect of blue light, at the intensity typically found in sunlight, on lipids in the skin from an oxidation perspective. Peroxide value (POV) and ultraweak photon emission (UPE) measurements were conducted to evaluate lipid oxidation. Our results confirmed that blue light irradiation induced lipid oxidation, similar to ultraviolet A (UVA) irradiation. Also, the effects of various reagents on the blue light-induced UPE were evaluated; however, the results differed from those of the DPPH radical-scavenging ability. We speculated that this is due to the difference in the evaluation principle; nevertheless, among reagents, hypotaurine not only showed a high antioxidant effect but was also more effective against blue light-induced oxidation than UVA. Based on the difference in the antioxidant effect of the lipid sample in this study, the oxidation reaction induced by blue light may be different from the UVA-induced reaction. Our study provides new insights into the effects of blue light on lipids in the human skin, thereby promoting research regarding photooxidation.

Effect of melatonin on oxidative stress indicators in animal models of fibrosis: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Imbalance of oxidative stress has been detected in a range of fibrotic diseases. Melatonin as an indoleamine hormone plays an important role in regulating the circadian rhythm of human, while in recent years, its antioxidant effect has also attracted increasing attention. This study aimed to perform a systematic review and meta-analysis to comprehensively evaluate the antioxidant effect of melatonin in animal models of fibrosis.

METHODS

The PubMed, Cochrane Library, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang database, China Science and Technology Journal Database (VIP), and SinoMed databases were searched from inception to March 1st, 2022 to retrieve eligible studies that evaluated the effect of melatonin supplementation on the levels of malondialdehyde (MDA), lipid peroxidation (LPO), nitric oxide (NO), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), and catalase (CAT) in animal models of fibrosis.

RESULTS

A total of 64 studies were included in this meta-analysis. The results showed that melatonin supplementation significantly reduced the levels of oxidative indicators including MDA (P < 0.00001), LPO (P < 0.00001) and NO (P < 0.0001), and elevated the levels of antioxidant indicators including GSH (P < 0.00001), GPx (P < 0.00001) and SOD (P < 0.00001) in fibrotic diseases.

CONCLUSIONS

Our research findings showed that melatonin supplementation could significantly reduce the levels of oxidative indicators including MDA, LPO and NO and elevate the levels of antioxidant indicators including GSH, GPx and SOD so as to correct oxidative stress in animal models of fibrosis. However, no significant changes were observed in CAT level. More clinical studies are needed to further confirm the beneficial role of melatonin in fibrotic diseases.

Phytocannabinoids in the Pharmacotherapy of Psoriasis

Phytocannabinoids are naturally occurring compounds, the main source of which is Cannabis sativa L. Through direct action or interaction with G protein-coupled receptors, they affect ROS and pro-inflammatory cytokines levels and modify the effectiveness of transcription factor responsible for the biosynthesis of antioxidants which lead to oxidative stress and its consequences. Due to the modification of the redox balance and inflammation, phytocannabinoids are used in the treatment of various diseases, including autoimmune dermatoses, such as atopic dermatitis and psoriasis. Psoriasis is one of the most common dermatoses, and one of unknown etiology. A disturbed redox balance with a shift towards the oxidation leads to oxidative stress, resulting in oxidative modifications, mainly of lipids and proteins, and prolonged activation of immune cells and increased generation of pro-inflammatory cytokines, resulting in chronic inflammation. Given the biological activity of phytocannabinoids, they have become the focus of research as components of pharmacotherapy for psoriasis. Beneficial effects were shown by various representatives of phytocannabinoids, but the effect of cannabidiol (CBD) on skin cells (in vitro and ex vivo) and on blood cells from patients with psoriasis vulgaris and psoriatic arthritis has been most often evaluated in recent years.