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5α,8α-peroxyergosteryl divaricatinate (1) is isolated for the first time from acetone extract of the thallus of Cladonia cf. didyma together with condidymic (2), isodidymic (3) and barbatic (4) acids. Their UVB/UVA photoprotective and antioxidant activities were determined along with their cyto- and DNA-protecting actions against OH• damage. Compound 1 showed high UVA, cyto- (%cell viability ca. 82 at 15 µM vs 71 for OH•) and DNA (%DNA-integrity ca. 74 at 100 µM vs 22 for OH•) protecting properties. Compounds 2 and 3 exhibited high UVB (SPF ca. 40) and antioxidant activities (free radical scavenging potency EC50 = 0.6694 and 1.700 mol compound/mol DPPH•; ferric reducing power 0.392 and 0.546, at 500 ppm and inhibited lipid peroxidation); protecting cells (%cell viability ca. 76 at 15 µM) and DNA (%DNA-integrity ca. 57 at 100 µM). Compounds 1 to 3 fulfilled some physicochemical properties to act topically on the skin. [ABSTRACT FROM AUTHOR]

As a newly defined type of programmed cell death, ferroptosis is considered a potent weapon against tumors due to its distinct mechanism from other types of programmed cell death. Ferroptosis is triggered by the uncontrolled accumulation of hydroperoxyl polyunsaturated fatty acid-containing phospholipids, also called lipid peroxidation. The lipid peroxidation, generated through enzymatic and non-enzymatic mechanisms, drives changes in cell morphology and the destruction of membrane integrity. Here, we dissect the mechanisms of ferroptosis induced enzymatically or non-enzymatically, summarize the major metabolism pathways in modulating lipid peroxidation, and provide insights into the relationship between ferroptosis and tumor suppression. In this review, we discuss the recent advances of ferroptosis in tumor microenvironments and the prospect of potential therapeutic application. A review summarizes the recent advances in ferroptosis and tumor suppression, including the metabolic regulation of lipid peroxidation, the role of ferroptosis in tumor immunity response, and ferroptosis-based tumor therapeutics and clinical trials. [ABSTRACT FROM AUTHOR]

Phenols play a crucial role as core structural motifs in natural products and also serve as fundamental building blocks in synthetic chemistry. Apart from the known protocols for the conversion of aryl precursors to phenols (i. e., decarboxylative oxygenation), we report here the efficient synthesis of phenols from the stable and readily available benzylic carboxylic acids under mild reaction conditions. The photocatalytic conversion of carboxylic acids to peroxides is a crucial step in this strategy, allowing the subsequent C−O bond formation via Hock rearrangement. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Macrocycles bridge the gap between conventional small molecules and polymers. Drawing inspiration from successful carbon heteroatom-containing macrocycles, peroxide-containing macrocycles are gaining attention for enhanced bioactivity, potential chelating properties, and applications in energetic materials. This review presents the following strategies for the construction of cyclic peroxides with 10- to 36-membered frameworks: (1) the intramolecular iodocyclization of hydroperoxides, (2) the intermolecular cyclization of hydroperoxides with alkyl dihalides or carbonyls, (3) the acid-catalyzed rearrangements of ozonides or 11-membered cyclic triperoxides via oxy- or peroxycarbenium ions, and (4) the peroxidation of carbonyls targeting macrocyclic peroxides. The specific agents that allow for the selective construction of the medium and large cycles are also analyzed. [ABSTRACT FROM AUTHOR]

The antioxidant activity of carnosine and of carnosine dinitrosyl iron complexes (DNICs) was studied. A system with metmyoglobin (metMb) or hemin in combination with tert-butyl hydroperoxide (t-BOOH) was used as an experimental model. Using the luminol-dependent chemiluminescence method, it was shown that carnosine and carnosine DNICs effectively diminished the level of prooxidants formed by the interaction of heme groups with t-BOOH. In addition, carnosine and carnosine DNICs inhibited the formation of diene conjugates arising during the oxidation of arachidonic acid in the metMb–t-BOOH system. In the reaction systems used, the antioxidant effect of carnosine DNICs was higher than that of carnosine. The antioxidant effect of carnosine also depended on the presence of bivalent iron ions added at a concentration equivalent to their content in DNICs. These results show that the insertion of carnosine as a ligand to nitrosyl iron complexes enhances its antioxidant properties. [ABSTRACT FROM AUTHOR]

Cryopreservation is a pivotal technique in safeguarding genetic material across diverse species, despite its inherent challenges linked to induced spermatozoa damage, notably apoptosis and lipid peroxidation (LPO). Given the insufficient antioxidant defense of spermatozoa against LPO, there is a rising interest in integrating additional additives into extenders to ameliorate mammalian semen quality. Among these additives, flavonoids have garnered considerable attention due to their potent antioxidative properties. Hence, our study aimed to assess the efficacy of flavone (FL) and 3-hydroxyflavone (3-OH =) supplementation in the cryopreservation medium to protect canine sperm against the damaging impacts of freezing and ensure the preservation of their reproductive potential. Semen was collected from five Beagle stud dogs and then pooled. Then, the sample was divided into 7 groups, each treated with 1) 0 mM, 2) 0.1 mM FL, 3) 0.2 mM FL, 4) 0.4 mM FL, 5) 0.1 mM 3-OH = , 6) 0.2 mM 3-OH = , 7) 0.4 mM 3-OH =. Semen samples were subjected to cryopreservation in French straws and glycerol as a cryoprotectant. In the frozen thawed semen, sperm motility parameters by CASA system and sperm membrane integrity, acrosome status, mitochondrial activity, DNA fragmentation, early apoptosis with capacitation, and LPO were assessed using flow cytometry just after thawing (0 h) and 4 h post thaw. Results reveal significant increase in the proportion of live spermatozoa with undamaged acrosomes in the FL 0.1 and 3-OH = 0.2 groups at 0 h post thaw. At this time point, 3-OH = 0.1 significantly reduced the DNA fragmentation index (DFI) compared to the FL 0.1 and 0.2 groups. However, after the next 4 h, 3-OH = 0.4 exhibited the lowest (P < 0.05) DFI compared to FL 0.2 and 3-OH = 0.1. Additionally, 3-OH = 0.4 showed the highest (P < 0.05) proportion of non apoptotic and non capacitated spermatozoa compared to FL 0.1 0 h post-thaw. Simultaneously, the same group demonstrated significant reduction in apoptotic and capacitated sperm cells, at 0 h and 4 h post-thaw. Moreover, 3-OH = at 0.1 (0 h and 4 h) and 0.2 mM (4 h) significantly enhances the proportion of live sperm without LPO post thaw. Whitin the FL groups, only 0.4 FL significantly increased the percentage of live sperm without LPO. No significant effect of the tested substances was observed on sperm motility, cell membrane integrity, or mitochondrial activity. These findings highlight the promising role of flavone and 3-hydroxyflavone in enhancing sperm resilience during cryopreservation, suggesting their protective function against acrosome damages, capacitation, apoptosis and lipid peroxidation. [Display omitted] • lFlavone (FL) and 3-hydroxyflavone (3-OH =) were used to supplement the extender for canine semen cryopreservation for the first time. • Using FL 0.1 mM and 3-OH = 0.2 mM increased (P < 0.05) the proportion of live spermatozoa with undamaged acrosomes. • Using 3-OH = 0.1 and 0.4 mM significantly reduced the DNA fragmentation index of spermatozoa. • Using 3-OH = 0.4 mM significantly reduced apoptosis and capacitation of sperm cells. • Using FL 0.4 mM and 3-OH = 0.1 and 0.2 mM significantly protected the sperm against lipid peroxidation. [ABSTRACT FROM AUTHOR]

Ferroptosis is a form of programmed cell death characterized by iron metabolic imbalance and lipid peroxidation. Alzheimer disease (AD) is a neurodegenerative condition. Studies have shown that lipid peroxidation through ferroptosis plays a significant role in the progression of AD. Ferroptosis suppressor protein 1 (FSP1 )/coenzyme Q10 (CoQ10) signaling axis serves as a crucial regulatory element in the process of lipid peroxidation associated with ferroptosis. This review explores the mechanisms of the FSP1/CoQ10 signaling axis in AD, aiming to present a novel therapeutic approach for AD treatment. [ABSTRACT FROM AUTHOR]

Ferroptosis is implicated in viral neuropathogenesis and may underlie HIV-associated neurocognitive impairment (NCI). Emerging data also suggest differences in brain iron transport by sex. We hypothesized that circulating ferritins that inhibit ferroptosis associate with neurocognitive function and NCI in people with HIV (PWH) in a sex-biased manner. Serum ferritin heavy-chain-1 (FTH1), ferritin light-chain (FTL), and urinary F2-isoprostanes (uF2-isoPs, specific lipid peroxidation marker) were quantified in 324 PWH (including 61 women) with serial global (NPZ-4) and domain-specific neurocognitive testing. Biomarker associations with neurocognitive test scores and NCIs were evaluated by multivariable regression; correlations with uF2-isoPs were also assessed. Higher FTL and FTH1 levels were associated with less NCI in all PWH (adjusted odds ratios 0.53, 95% confidence interval (95% CI) 0.36–0.79 and 0.66, 95% CI 0.45–0.97, respectively). In women, higher FTL and FTH1 were also associated with better NPZ-4 (FTL adjusted beta (β) = 0.15, 95% CI 0.02–0.29; FTL-by-sex βinteraction = 0.32, p = 0.047) and domain-specific neurocognitive test scores. Effects on neurocognitive performance persisted for up to 5 years. Levels of both ferritins correlated inversely with uF2-isoPs in women (FTL: rho = −0.47, p < 0.001). Circulating FTL and FTH1 exert sustained, sex-biased neuroprotective effects in PWH, possibly by protecting against iron-mediated lipid peroxidation (ferroptosis). Larger studies are needed to confirm the observed sex differences and further delineate the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Macrocycles bridge the gap between conventional small molecules and polymers. Drawing inspiration from successful carbon heteroatom-containing macrocycles, peroxide-containing macrocycles are gaining attention for enhanced bioactivity, potential chelating properties, and applications in energetic materials. This review presents the following strategies for the construction of cyclic peroxides with 10- to 36-membered frameworks: (1) the intramolecular iodocyclization of hydroperoxides, (2) the intermolecular cyclization of hydroperoxides with alkyl dihalides or carbonyls, (3) the acid-catalyzed rearrangements of ozonides or 11-membered cyclic triperoxides via oxy- or peroxycarbenium ions, and (4) the peroxidation of carbonyls targeting macrocyclic peroxides. The specific agents that allow for the selective construction of the medium and large cycles are also analyzed.

It is well known, that antitumor drug cisplatin is an antineoplastic drug which widely used in chemotherapy. However, the usage has been limited due to cisplatin-caused various side effects. It has been established that toxic effects of cisplatin are the result of oxidative stress. Oxidative stress is the result of the excessive formation of reactive oxygen species, that can be induced by cisplatin. The reactive oxygen species in turn can interact with DNA, lipids and proteins, leading to lipid peroxidation and DNA damage. Dexamethasone is being used in chemotherapy practice as concomitant agent to mitigate the side effects of antitumor drug cisplatin. It is known that both cisplatin and dexamethasone are capable of stimulating the production of reactive oxygen species, which in turn target various biomolecules, including lipids. The aim of this study was to evaluate the quantitative alterations in lipid peroxidation products within the nuclei of cells from various rat tissues following the separate and combined administration of cisplatin and dexamethasone. The amount of lipid peroxidation products was determined using a spectrophotometric method, following extraction with a heptane-isopropanol mixture. When administered individually, cisplatin and dexamethasone increase the formation of lipid peroxidation products in the examined tissues of rats to varying degrees. As a result, these alterations led to corresponding changes in the oxidation index values of the analyzed nuclear preparations. During the combined administration of cisplatin and dexamethasone, some antagonistic effects were observed in the actions of these agents. Contrary to the expected synergistic enhancement of lipid peroxidation processes, a reduction in cisplatin's effect by dexamethasone was observed. Thus, it is hypothesized that such antagonistic effect of dexamethasone together with its antiinflammatory and immunomodulatory properties allows to mitigate the side effects of cisplatin. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) is a platinum-based drug with anti-cancer activity and is widely used as a standard therapy for bladder cancer. It is well known that CDDP causes cell death by increasing the generation of reactive oxygen species (ROS) and lipid peroxidation, but the mechanism of its anti-cancer effects has not been fully elucidated. There are still some problems such as chemoresistance in CDDP therapy. In the present study, we found the expression of Ca2+-independent phospholipase A 2 γ (iPLA 2 γ), which has been reported to regulate cellular redox homeostasis by inhibiting lipid peroxide accumulation, in human bladder cancer tissues. Thus, we investigated the effect of iPLA 2 γ knockdown on CDDP-induced bladder cancer cell death. As a result, we found that iPLA 2 γ knockdown significantly enhanced CDDP-induced apoptosis, intracellular and mitochondrial ROS production, cytochrome c release and caspase activation in bladder cancer cells. Moreover, mitochondrial membrane potential was decreased and peroxidation of mitochondrial phospholipids was increased by iPLA 2 γ knockdown. It was also shown that co-treatment of bromoenol lactone, an iPLA 2 inhibitor, increased CDDP-induced apoptosis. These results indicated that iPLA 2 γ plays an important role in protecting bladder cancer cells from CDDP-induced apoptosis, and that iPLA 2 γ inhibitors might represent a novel strategy in CDDP-based multi-drug therapy. [Display omitted] • iPLA 2 γ knockdown enhanced CDDP-induced apoptosis of bladder cancer cells. • iPLA 2 γ knockdown accelerated CDDP-induced mitochondrial oxidative stress. • iPLA 2 γ knockdown increased CDDP-induced peroxidation of cardiolipin. • Inhibition of iPLA 2 γ might represent a novel strategy in CDDP-based drug therapy. [ABSTRACT FROM AUTHOR]

Onions contain valuable phytochemical compounds, including quercetin derivatives. This study explores the potential of onion extract as a natural additive in chicken patties. The optimized conditions involved sonication at 80% for 5 min with a 75% ethanol concentration. The onion extract exhibited total phenolic and flavonoid compound values of 255.63 mg GAE g−1 DR and 196.87 mg QE g−1 DR, respectively. The antioxidant activity of the onion extract was characterized by an IC50 of 12.74 µg/mL. This onion extract was dominated by quercetin derivatives (quercetin 4’-O-β-glycoside and quercetin-3-O-β-glycoside and quercetin-3,4’-O-β-diglycoside). Chicken patties treated with 2% onion extract exhibited superior pH stability, lowest thiobarbituric acid reactive substances level (0.40 mg/kg) and peroxide index (0.77 mEq O2/kg meat) and maintained color stability. Comparative analysis with BHT demonstrated the efficacy of onion extract in reducing lipid oxidation. These findings highlight the potential of a 2% onion extract as effective ingredient for enhancing the quality of chicken products. [ABSTRACT FROM AUTHOR]

Disruption of the thyroid hormone (TH) system is connected with diverse adverse health outcomes in wildlife and humans. It is crucial to develop and validate suitable in vitro assays capable of measuring the disruption of the thyroid hormone (TH) system. These assays are also essential to comply with the 3R principles, aiming to replace the ex vivo tests often utilised in the chemical assessment. We compared the two commonly used assays applicable for high throughput screening [Luminol and Amplex UltraRed (AUR)] for the assessment of inhibition of thyroid peroxidase (TPO, a crucial enzyme in TH synthesis) using several cell lines and 21 compounds from different use categories. As the investigated cell lines derived from human and rat thyroid showed low or undetectable TPO expression, we developed a series of novel cell lines overexpressing human TPO protein. The HEK-TPOA7 model was prioritised for further research based on the high and stable TPO gene and protein expression. Notably, the Luminol assay detected significant peroxidase activity and signal inhibition even in Nthy-ori 3-1 and HEK293T cell lines without TPO expression, revealing its lack of specificity. Conversely, the AUR assay was specific to TPO activity. Nevertheless, despite the different specificity, both assays identified similar peroxidation inhibitors. Over half of the tested chemicals with diverse structures and from different use groups caused TPO inhibition, including some widespread environmental contaminants suggesting a potential impact of environmental chemicals on TH synthesis. Furthermore, in silico SeqAPASS analysis confirmed the high similarity of human TPO across mammals and other vertebrate classes, suggesting the applicability of HEK-TPOA7 model findings to other vertebrates. [ABSTRACT FROM AUTHOR]

This research aimed to study the long-term effects of soccer training on platelet membrane fatty acid levels and antioxidant vitamins. Forty-four subjects divided into soccer players (SP; n = 22; 20.86 ± 0.36 years) and a control group (CG; n = 22; 21.23 ± 0.49 years) participated in the study. The fatty acids of the platelet membrane, the rates of desaturation, lipid peroxidation indexes and intra-platelet levels of vitamins C and E were assessed. SP obtained lower values in polyunsaturated fatty acids 18:3:3 (alpha-linolenic acid), 20:5:3 (eicosapentaenoic acid) and 22:6:3 (docosahexaenoic acid) (p < 0.05). The desaturation index ∆5 was higher in SP (p < 0.05), and they had a higher lipid peroxidation index 20:4:6 (arachidonic acid)/16:0 (palmitic acid) (p < 0.05). Vitamin E and C platelet values were also higher in SP (p < 0.01). There were positive correlations in the ω6/ω3 index (p < 0.05), desaturation index ∆5 (p < 0.05), lipid peroxidation index 20:4:6/16:0 and intra-platelet vitamins E and C (p < 0.01) with the level of physical activity. In addition, there were inverse correlations in fatty acids 24:0 (lignoceric acid), 16:1 (palmitoleic acid), 20:3:6 (eicosadienoic acid) and 18:3:3 (alpha-linolenic acid) (p < 0.05) depending on the degree of physical activity. Regular long-term soccer training could modify the concentration of fatty acids such as 24:0, 16:1, 18:6, 20:3:6, 18:3:3:3, 20:5:3, 26:6:3 and ω3 PUFAs in the platelet membrane. [ABSTRACT FROM AUTHOR]

The dynamics of water physicochemical properties and hydrochemical characteristics in the Dubna River was studied from April 18, 2021 to July 4, 2021. The study showed an increase in pH with increasing water temperature and considerable variation in the concentrations of ammonium, nitrite, and phosphate ions in it. Promising approaches were shown to be the use of mathematical processing of UV-spectra of water samples by Gauss method and model biological systems based on natural lipids (low-temperature oxidation of lecithin, and its ability to spontaneously aggregate in a polar environment) for assessing the quality of natural water and its effect on the regulation of oxidation processes in biological objects. Thus, analysis of UV-spectra revealed the presence in water of hydrophobic organic compounds throughout the observation period, compounds with conjugated double bonds and N-containing compounds in late April, free fatty acids, organic compounds with a carbonyl group and P-containing compounds at the end of May and an increase in the diversity of components in water samples in late June. Water samples taken in summer, increased the rate of lecithin oxidation by a factor of more than 1.8, and, throughout the observation period, they caused staged changes in the size of aggregates formed by it and produced a considerable effect on their dzeta-potential. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Epithelial–Mesenchymal Transition (EMT) of retinal pigment epithelial (RPE) cells is recognized as pivotal in various retinal diseases. Previous studies have suggested a reciprocal regulation between reactive oxygen species (ROS) and EMT, though the involvement of peroxidized lipids or the effects of reducing them has remained unclear. The present study disclosed that EMT of ARPE-19 cells induced by TGF-β2 and TNF-α involves increased lipid peroxidation, and Ferrostatin-1 (Fer-1), a lipophilic antioxidative agent, successfully inhibited the increase in lipid peroxidation. Fer-1 suppressed the formation of EMT-associated fibrotic deposits, while EMT induction or Fer-1 treatment did not influence the cell viability or proliferation. Functionally, Fer-1 impeded EMT-driven cell migration and reduction in transepithelial electrical resistance. It demonstrated regulatory prowess by downregulating the mesenchymal marker fibronectin, upregulating the epithelial marker ZO-1, and inhibiting the EMT-associated transcriptional factor ZEB1. Additionally, VEGF, a major pathogenic cytokine in various retinal diseases, is also upregulated during EMT, and Fer-1 significantly mitigated the effect. The present study disclosed the involvement of lipid peroxidation in EMT of RPE cells, and suggests the suppression of lipid peroxidation may be a potential therapeutic target in retinal diseases in which EMT is implicated. [ABSTRACT FROM AUTHOR]

Ferroptosis is a type of nonapoptotic cell death that is characteristically caused by phospholipid peroxidation promoted by radical reactions involving iron. Researchers have identified many of the protein factors that are encoded by genes that promote ferroptosis. Glutathione peroxidase 4 (GPX4) is a key enzyme that protects phospholipids from peroxidation and suppresses ferroptosis in a glutathione-dependent manner. Thus, the dysregulation of genes involved in cysteine and/or glutathione metabolism is closely associated with ferroptosis. From the perspective of cell dynamics, actively proliferating cells are more prone to ferroptosis than quiescent cells, which suggests that radical species generated during oxygen-involved metabolism are responsible for lipid peroxidation. Herein, we discuss the initial events involved in ferroptosis that dominantly occur in the process of energy metabolism, in association with cysteine deficiency. Accordingly, dysregulation of the tricarboxylic acid cycle coupled with the respiratory chain in mitochondria are the main subjects here, and this suggests that mitochondria are the likely source of both radical electrons and free iron. Since not only carbohydrates, but also amino acids, especially glutamate, are major substrates for central metabolism, dealing with nitrogen derived from amino groups also contributes to lipid peroxidation and is a subject of this discussion. [ABSTRACT FROM AUTHOR]

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4−) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4−. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4− efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Critical seagrass ecosystems are predicted to be impacted by droughts and floods of increasing severity and frequency as the climate changes. Hyposalinity events alter seagrass composition and challenge resilience, yet understanding of the response mechanisms is incomplete but necessary for predicting outcomes. Hyposalinity stress response mechanisms in Halodule wrightii (shoal grass), a seagrass with wide salinity tolerance, were examined in mesocosm experiments by measuring monovalent and divalent ions, free amino acid (FAA) concentrations, and the Thiobarbituric Acid Reactive Substances (TBARS) indicator of lipid peroxidation. Two progressive, 3-step treatments, to moderate and extreme hyposalinity endpoints S15 and S5 were compared. Concentrations of Na+, K+, Ca2+, and Cl− decreased two to threefold with greater hyposalinity. Proline, the most abundant FAA initially, progressively decreased with increasing hyposalinity as asparagine became dominant. Glutamine and serine increased significantly, and all four FAA exhibited consistent patterns of change. Results are consistent with proline's role as osmolyte and regulator, and suggest that asparagine mobilizes or stores N, possibly due to another limiting nutrient. TBARS changed transiently at intermediate salinities, but were not significantly different at hyposalinity endpoints indicating that H. wrightii may have already reached stress equilibrium. Prolonged hyposalinity events may have consequences for seagrass resilience. [ABSTRACT FROM AUTHOR]

Excessive fat deposition due to impaired fat metabolism in chickens is a major problem in the poultry industry. Nutritional interventions are effective solutions, but current options are limited. A safe phytochemical, rutin, has shown positive effects in animals, but its effect on lipid metabolism in poultry remains unknown. Hence, this study is to investigate the effects of rutin on egg quality, serum biochemistry, fat deposition, lipid peroxidation and hepatic lipid metabolism in post-peak laying hens. A total of 360 Taihang laying hens (49-week-old) were randomly divided into five groups and fed a basal diet (control group, 0%) and a basal diet supplemented with 300 (0.03%), 600 (0.06%), 900 (0.09%), and 1,200 (0.12%) mg rutin/kg feed, respectively. The results showed that eggshell strength was significantly (p < 0.05) higher in the dietary rutin groups, whereas yolk percentage (p < 0.05), total cholesterol (TC) (p < 0.01) and yolk fat ratio (p < 0.01) decreased linearly (p < 0.05) in the dietary rutin groups. Importantly, dietary rutin reduced serum triglyceride (TG) and TC levels, decreased abdominal lipid deposition and liver index (p < 0.05), and which concomitantly decreased hepatic lipid (TG, TC, and free fatty acid) accumulation (p < 0.05). An increase (p < 0.05) in total antioxidant capacity and superoxide dismutase activity and a decrease (p < 0.05) in malondialdehyde levels were also found. At the same time, the activities of hepatic lipase, acetyl-CoA carboxylase and malic enzyme in the liver were decreased (p < 0.05). Dietary rutin also increased (p < 0.05) the expression of fatty acid oxidation-related genes (carnitine palmitoyl transferase 1, peroxisome proliferator-activated receptor α, farnesoid X receptor). Additionally, it decreased fatty acid synthesis genes (sterol regulatory element binding protein-1c, acetyl-CoA carboxylase α, stearoyl-CoA desaturase 1) (p < 0.05). In conclusion, the addition of rutin (0.06-0.12%) to the diet improved the fat metabolism and increased liver antioxidant capacity in post-peak laying hens, and these positive changes improved egg quality to some extent. [ABSTRACT FROM AUTHOR]

Lipid peroxidation plays an important role in various pathologies and aging, at least partially mediated by ferroptosis. The role of mitochondrial lipid peroxidation during ferroptosis remains poorly understood. We show that supplementation of exogenous iron in the form of ferric ammonium citrate at submillimolar doses induces production of reactive oxygen species (ROS) and lipid peroxidation in mitochondria that precede ferroptosis in H9c2 cardiomyocytes. The mitochondria-targeted antioxidant SkQ1 and the redox mediator methylene blue, which inhibits the production of ROS in complex I of the mitochondrial electron transport chain, prevent both mitochondrial lipid peroxidation and ferroptosis. SkQ1 and methylene blue also prevented accumulation of lipofuscin observed after 24 h incubation of cardiomyocytes with ferric ammonium citrate. Using isolated cardiac mitochondria as an in vitro ferroptosis model, it was shown that rotenone (complex I inhibitor) in the presence of ferrous iron stimulates lipid peroxidation and lipofuscin accumulation. Our data indicate that ROS generated in complex I stimulate mitochondrial lipid peroxidation, lipofuscin accumulation, and ferroptosis induced by exogenous iron. [ABSTRACT FROM AUTHOR]

Background: After hypovolemic shock caused by severe burns, lipid peroxidation is an important factor in tissue edema and multiorgan dysfunction syndrome (MODS). Many studies have shown that valproic acid (VPA) inhibits lipid peroxidation and reduces tissue and organ injury. Objectives: This study investigated whether the VPA treatment of scalded rats reduced tissue edema by inhibiting lipid peroxidation, thereby improving organ function and survival rate. Materials and Methods: A total of 60 male Sprague-Dawley rats (weighing: 280–300 g) with a 50% total body surface area (TBSA) full-thickness dermal burn were randomly assigned to the following 3 groups (with 20 rats per group): (I) the no infusion resuscitation (NR) group; (II) the sodium lactate Ringer's solution (LR) group; and (III) the sodium valproate Ringer's solution (VR) group. After scalding, the following hemodynamic parameters were measured: Copper2+-Zinc2+-superoxide dismutase (Cu2+-Zn2+-SOD) activity, thiobarbituric acid reactive substances (TBARSs), oxidized glutathione (GSSG), reduced glutathione (GSH), and antioxidant enzyme activities. Organ function parameters and water content were also measured. Another 60 male Sprague-Dawley rats were used to observe the 24-h survival rate of the rats using the same scald model and fluid resuscitation. Results: VPA significantly increased the mean arterial pressure (MAP) and cardiac output (CO), and significantly decreased the pulmonary vascular permeability index (PVPI) and extravascular lung water index (ELWI). VPA also increased plasma Cu2+-Zn2+-SOD activity and decreased the plasma TBARS level. VPA reduced the TBARS level and GSSG in various tissues and increased the concentration of GSH. VPA decreased glutathione peroxidase (GPx) and catalase (CAT) activity, but significantly increased glutathione reductase (GR) activity in various tissues. VPA significantly improved organ functions and decreased water content. VPA significantly improved the survival rate, and the 24-h survival rate of the VR group was double that of the LR group. Conclusion: Resuscitation with VPA reduced tissue edema, protected visceral functions, and improved the survival rate of rats with severe burn shock (BS) by alleviating lipid peroxidation. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the antioxidant action of caffeine at various concentrations in TEYC extenders. In the present study, a total 64 ejaculates (16/buck) were collected from all four Surti bucks (age>12 months) i.e. two collections/week for 8 weeks. Ejaculates at each collection were pooled and divided into four groups viz. C1 (Control), C2, C3 and C4 having caffeine concentrations @ 0, 1, 3 and 5mM in TEYC extender, respectively with 100x106 sperm/ ml. Oxidative stress marker for lipid peroxidation (Malondialdehyde, MDA) and antioxidant (Glutathione, GSH) were determined at initial, pre-freeze and post-thaw; whereas, motility degeneration rate (MDR) of sperms was evaluated at pre-freeze and post-thaw. A decrease in GSH and an increase in MDA levels with elapse of time were found to be significant (p<0.01) between different phases. The MDA levels were observed to be significantly (p<0.01) different between groups that were highest in C1 and lowest in C4 in contrast to GSH levels that were highest in C4 and lowest in C1 groups. MDR was significantly (p<0.01) higher at post-thaw than pre-freeze in all the groups. Moreover, MDR was significantly (p<0.01) lower in C2 group as compared with other groups at both the pre-freeze and post-thaw stage. It was therefore concluded that for cryopreservation of Surti buck semen, supplementation of caffeine in TEYC extender has dose-dependent increase in antioxidant defense and decrease in oxidative stress as indicated by higher GSH and lower lipid peroxidation, respectively but 1mM caffeine concentration in TEYC is optimum and better owing to the lowest MDR. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron‐dependent cell death form that initiates lipid peroxidation (LPO) in tumors. In recent years, there has been growing interest on ferroptosis, but how to propel it forward translational medicine remains in mist. Although experimental ferroptosis inducers such as RSL3 and erastin have demonstrated bioactivity in vitro, the poor antitumor outcome in animal model limits their development. In this study, we reveal a novel ferroptosis inducer, oxaliplatin–artesunate (OART), which exhibits substantial bioactivity in vitro and vivo, and we verify its feasibility in cancer immunotherapy. For mechanism, OART induces cytoplasmic and mitochondrial LPO to promote tumor ferroptosis, via inhibiting glutathione‐mediated ferroptosis defense system, enhancing iron‐dependent Fenton reaction, and initiating mitochondrial LPO. The destroyed mitochondrial membrane potential, disturbed mitochondrial fusion and fission, as well as downregulation of dihydroorotate dehydrogenase mutually contribute to mitochondrial LPO. Consequently, OART enhances tumor immunogenicity by releasing damage associated molecular patterns and promoting antigen presenting cells maturation, thereby transforming tumor environment from immunosuppressive to immunosensitive. By establishing in vivo model of tumorigenesis and lung metastasis, we verified that OART improves the systematic immune response. In summary, OART has enormous clinical potential for ferroptosis‐based cancer therapy in translational medicine. [ABSTRACT FROM AUTHOR]

A traditional source of natural bioactive compounds, mushrooms are used to synthesize biomaterials, thanks to their potential applications in the medicine, pharmacology and cosmetics industries. In this study, the vitamin C and E contents of the Hebeloma excedens mushroom species were determined as 64.2 mg/g and 38.6 mg/g, respectively. In the mineral substance analysis, the highest amount of magnesium (32.16 mg/g) and trace amounts of iron (0.22 mg/g) were detected. In the nanoparticles (AgNPs/He) synthesized using this mushroom species, the colour of the mixture first changed to dark brown and exhibited maximum absorption at 428 nm, corresponding to the surface plasmon resonance. Fourier transform infrared spectroscopy (FTIR) results revealed the binding properties of the biocomponents responsible for coating and stabilizing the nanoparticles. The resulting nanostructures were much more stable than the mushroom extract and showed strong antioxidant activity (22.93 mg/ml). A significant decrease in phenolic compounds was observed after the gastrointestinal digestion process applied to the mushroom extract and AgNPs/He samples (p < 0.05). However, a significant increase in the bioaccessibility of phenolic compounds was detected in AgNPs/He particles (p < 0.05). It was determined that there was a significant increase in the thermal stability, inhibition against lipid peroxidation (6.64 mg/ml) and antidiabetic activities (29.20 mg/ml) of silver structures synthesized using the green synthesis method. As a result, the existence and current potential of a new biomaterial suitable for cost-effective and large-scale production in the synthesis of AgNPs/He has been demonstrated for the first time. [ABSTRACT FROM AUTHOR]

Preeclampsia is described as a systemic illness associated with pregnancy. It is characterized by symptoms such as edema, proteinuria (the presence of excess proteins in the urine), hypertension (high blood pressure), and dysfunction. Recent research has extensively investigated the role of oxidative stress in the pathophysiology of preeclampsia. Oxidative stress refers to an imbalance between the production of reactive oxygen species and the body's ability to detoxify them or repair the resulting damage. Despite the research focus on oxidative stress, there is currently no consensus among researchers regarding the mechanisms that lead to the occurrence of preeclampsia in expectant mothers. The present review aims to advance the understanding of the underlying causes of preeclampsia by addressing the main biomarkers of oxidative stress. In summary, preeclampsia is a complex condition associated with pregnancy, and its pathophysiology has been the subject of extensive research, particularly in connection to oxidative stress. However, the lack of agreement among researchers indicates that the exact mechanisms leading to preeclampsia in expectant mothers are still not fully understood and may vary across different studies or perspectives.

Blackcurrant (Ribes nigrum L.) is a berry bush widely cultivated in Europe for producing juices, jams, jellies, and syrups. In addition to berries, blackcurrant leaves and pomace, as byproducts, have also been shown to have health-promoting effects. Static digestion, simulating oral, gastric, and small intestinal digestion, was applied, and blackcurrant leaves, fruits, and pomace and the polyphenol bioaccessibility were evaluated in terms of recovery index. The results were related to sample type, and the recovery index presented higher values in the case of fruits, indicating this morphological part of blackcurrant as the most bioaccessible. The antioxidant potential of blackcurrant was evaluated using four different methods, with the leaves proving to be a significant and powerful antioxidant compared to fruits and pomace. The counteracting potential of inhibiting the oxidation process was evaluated using in vitro-induced lipid peroxidation and the inhibition potential of superoxide and hydroxyl anions. The antioxidant evaluation and the inhibition of biological and non-biological radicals indicate the leaf extract is the most powerful antioxidant studied. Also, the results proved that not only fruits but also the blackcurrant byproducts (pomace and leaves) are promising sources of bioaccessible antioxidants with potential benefits in animal nutrition. [ABSTRACT FROM AUTHOR]

The effects of combined short-term (3 days) exposure to Fusarium mycotoxins at both the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB1: 20 mg/kg) and twice the dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg/kg, and FB1: 40 mg/kg feed) on the kidneys of laying hens were examined. Our study aimed to investigate how these mycotoxins interacted with membrane lipid fatty acid (FA) composition and lipid peroxidation processes. It was observed that the levels of conjugated dienes and trienes were higher than the control in the low-mix group on day 3, and malondialdehyde concentration was higher on days 2 and 3. The proportion of phospholipid (PL) FAs showed that saturated and monounsaturated FAs increased. Still, both n3 and n6 polyunsaturated FAs decreased significantly on day 2 of exposure in the high-mix group. Among the n3 FAs, the level of docosahexaenoic (C22:6 n3) and among n6 FAs, arachidonic (C20:4 n6) acids decreased mainly on day 2 in the high-mix group. The results suggest that the combined exposure to Fusarium mycotoxins induced lipid peroxidation in the kidneys of laying hens, which resulted in marked changes in the PL FA profile. Histological examination revealed time- and dose-dependent increases as consequences of mycotoxin exposure. [ABSTRACT FROM AUTHOR]

The occurrence of internal browning in radish root is closely related to lipid peroxidation caused by excessive ROS production via NADPH-dependent ROS burst during the latter half of maturation. Japanese radish (Raphanus sativus L.) roots with differing severities of internal browning (IB) disorder grown under different soil temperatures were collected, and expression analysis of genes involved in NADPH-dependent ROS burst, mitochondrial electron transport chain, and ascorbate–glutathione cycle was performed. Roots with IB disorder were frequently found in higher soil temperature plots but rarely in the low soil temperature plot. Accumulation of metabolic products derived from the Maillard reaction and oxidative stress response was greater at higher soil temperatures. Although the content of hydrogen peroxide increased at higher soil temperatures, no clear correlation was found for sugar content among the experimental plots. Higher gene expressions related to NADPH-dependent ROS burst were detected at higher soil temperatures. Comparison of gene expression related to the mitochondrial electron transport chain in roots grown under different soil temperatures showed that the expression of complexes I- and III-related genes did not differ among the experimental plots. Furthermore, higher gene expressions related to the ascorbate–glutathione cycle were detected at higher soil temperatures. These facts indicate that the activation of NADPH-dependent oxidative burst induced by high temperatures increases lipid peroxidation, resulting in IB disorder in radish root. [ABSTRACT FROM AUTHOR]

Preeclampsia, a serious and potentially life-threatening medical complication occurring during pregnancy, is characterized by hypertension and often accompanied by proteinuria and multiorgan dysfunction. It is classified into two subtypes based on the timing of diagnosis: early-onset (EO-PE) and late-onset preeclampsia (LO-PE). Despite being less severe and exhibiting distinct pathophysiological characteristics, LO-PE is more prevalent than EO-PE, although both conditions have a significant impact on placental health. Previous research indicates that different pathophysiological events within the placenta may contribute to the development of preeclampsia across multiple pathways. In our experimental study, we investigated markers of oxidative stress, ferroptosis, and lipid peroxidation pathways in placental tissue samples obtained from women with LO-PE (n = 68) compared to healthy control pregnant women (HC, n = 43). Through a comprehensive analysis, we observed an upregulation of specific molecules associated with these pathways, including NADPH oxidase 1 (NOX-1), NADPH oxidase 2 (NOX-2), transferrin receptor protein 1 (TFRC), arachidonate 5-lipoxygenase (ALOX-5), acyl-CoA synthetase long-chain family member 4 (ACSL-4), glutathione peroxidase 4 (GPX4) and malondialdehyde (MDA) in women with LO-PE. Furthermore, increased ferric tissue deposition (Fe3+) was observed in placenta samples stained with Perls' Prussian blue. The assessment involved gene and protein expression analyses conducted through RT-qPCR experiments and immunohistochemistry assays. Our findings underscore the heightened activation of inflammatory pathways in LO-PE compared to HC, highlighting the pathological mechanisms underlying this pregnancy disorder. [ABSTRACT FROM AUTHOR]

In this work, we aim to find physical evidence demonstrating the crucial role that the effective concentration of antioxidants (AOs) present at the interfacial region of emulsions has in controlling the inhibition of the lipid oxidation reaction. We prepared a series of antioxidants of different hydrophobicities derived from chlorogenic and protocatechuic acids. We first monitored, in intact emulsions, the (sigmoidal) production of conjugated dienes and determined the corresponding induction times, tind. Independently, we determined the effective concentrations of the antioxidants in the same intact emulsions. Results show that both the length of the induction periods and the antioxidant interfacial concentrations parallel each other, with a maximum at the octyl-dodecyl derivatives. The ratio between the interfacial antioxidant concentrations and the induction periods remains constant for all AOs in the same series, so that the rates of initiation of lipid oxidation are the same regardless of the hydrophobicity of the antioxidant employed. The constancy in the rate of initiation provides strong experimental evidence for a direct relationship between interfacial concentrations and antioxidant efficiencies. Results suggest new possibilities to investigate lipid peroxidation under non-forced conditions and are of interest to formulators interested in preparing emulsions with antimicrobial properties. [ABSTRACT FROM AUTHOR]

A sudden increase in polyurethane (PU) production necessitates viable recycling methods for the waste generated. PU is one of the most important plastic materials with a wide range of applications; however, the stability of the urethane linkage is a major issue in chemical recycling. In this work, termination reactions of a model urethane molecule, namely methyl N-phenyl carbamate (MPCate), are investigated using G3MP2B3 composite quantum chemical method. Our main goal was to gain insights into the energetic profile of urethane bond termination and find an applicable chemical recycling method. Hydrogenation, hydrolysis, methanolysis, peroxidation, glycolysis, ammonolysis, reduction with methylamine and termination by dimethyl phosphite were explored in both gas and condensed phases. Out of these chemicals, degradation by H2, H2O2 and CH3NH2 revealed promising results with lower activation barriers and exergonic pathways, especially in water solvation. Implementing these effective PU recycling methods can also have significant economic benefits since the obtained products from the reactions are industrially relevant substances. For example, aniline and dimethyl carbonate could be reusable in polymer technologies serving as potential methods for circular economy. As further potential transformations, several ionizations of MPCate were also examined including electron capture and detachment, protonation/deprotonation and reaction with OH−. Alkaline digestion against the model urethane MPCate was found to be promising due to the relatively low activation energy. In an ideal case, the transformation of the urethane bond could be an enzymatic process; therefore, potential enzymes, such as lipoxygenase, were also considered for the catalysis of peroxidation, and lipases for methanolysis. [ABSTRACT FROM AUTHOR]

Pea (Pisum sativum L.), a globally cultivated leguminous crop valued for its nutritional and economic significance, faces a critical challenge of soil salinity, which significantly hampers crop growth and production worldwide. A pot experiment was carried out in the Botanical Garden, The Islamia University of Bahawalpur to alleviate the negative impacts of sodium chloride (NaCl) on pea through foliar application of ascorbic acid (AsA). Two pea varieties Meteor (V1) and Sarsabz (V2) were tested against salinity, i.e. 0 mM NaCl (Control) and 100 mM NaCl. Three levels of ascorbic acid 0 (Control), 5 and 10 mM were applied through foliar spray. The experimental design was completely randomized (CRD) with three replicates. Salt stress resulted in the suppression of growth, photosynthetic activity, and yield attributes in pea plants. However, the application of AsA treatments effectively alleviated these inhibitory effects. Under stress conditions, the application of AsA treatment led to a substantial increase in chlorophyll a (41.1%), chl. b (56.1%), total chl. contents (44.6%) and carotenoids (58.4%). Under salt stress, there was an increase in Na+ accumulation, lipid peroxidation, and the generation of reactive oxygen species (ROS). However, the application of AsA increased the contents of proline (26.9%), endogenous AsA (23.1%), total soluble sugars (17.1%), total phenolics (29.7%), and enzymatic antioxidants i.e. SOD (22.3%), POD (34.1%) and CAT (39%) in both varieties under stress. Salinity reduced the yield attributes while foliarly applied AsA increased the pod length (38.7%), number of pods per plant (40%) and 100 seed weight (45.2%). To sum up, the application of AsA alleviated salt-induced damage in pea plants by enhancing photosynthetic pigments, both enzymatic and non-enzymatic activities, maintaining ion homeostasis, and reducing excessive ROS accumulation through the limitation of lipid peroxidation. Overall, V2 (Sarsabz) performed better as compared to the V1 (Meteor). [ABSTRACT FROM AUTHOR]

Summary: Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome‐wide CRISPR‐Cas9 loss‐of‐function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2‐deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4‐CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co‐treatment of 4‐CBA and RSL3 induced cell death in bortezomib‐resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients. [ABSTRACT FROM AUTHOR]

Ascites or pulmonary hypertension syndrome is one of the common complications in the poultry industry, which is associated with symptoms such as increased pulmonary artery pressure, dilatation and hypertrophy of the right ventricle. Previous experiments have proven that the measurement of lipid peroxidation is a key indicator for detecting oxidative stress. It has also been determined that the ratio of heterophile/lymphocyte increases in stress conditions and can be helpful in the diagnosis of oxidative stress. Considering the antioxidant role of prebiotics, there is a possibility that these compounds can reduce the oxidative stress in pulmonary hypertension. In the current study, in order to measure this hypothesis, 135 broilers were purchased and divided into three groups of 45 pieces in three repetitions: sham group: basal diet, control group: basal diet + triiodothyronine (T3) (1.5 mg/kg) to induce ascites, and treatment group: basal diet + T3 (1.5 mg/kg) + Safmannan (1000 grams per ton) from one day old. At the age of 21, 35, and 49 days, 9 chickens from each group were randomly selected and after blood sampling, blood parameters including lymphocytes, heterophil, heterophil/lymphocyte and and the ratio of right ventricular to the total ventricles (RV/TV) weight as well as lipid peroxidation were assayed. According to the findings, the RV/TV increased significantly at the age of 49 days in the positive control group and reached above 0.29, which indicates the presence of ascites in this group (P<0.05). The ratio of heterophils to lymphocytes at the age of 49 days in the prebiotic treatment group demonstrated a meaningful reduction compared to the positive control group, and also the amount of lipid peroxidation at the ages of 35 and 49 days in the prebiotic treatment group decreased compared to the positive control group (P<0.05). According to the results of the current research, Safmannan prebiotic was able to remarkably decrease the amount of oxidative stress caused by ascites. [ABSTRACT FROM AUTHOR]

Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: 20 mg/kg) and double dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg, and FB1: 40 mg/kg feed) were investigated during short-term (3 days) per os exposure in the liver of laying hens. On day 1 higher while on day 3 lower MDA concentrations were found in the low-dose group compared to the control. Fatty acid composition also changed: the proportion of monounsaturated fatty acids increased (p < 0.05) and the proportion of polyunsaturated fatty acids decreased by day 3. These alterations resulted in a decrease in the index of unsaturation and average fatty acid chain length. Histopathological alterations suggested that the incidence and severity of liver lesions were higher in the mycotoxin-treated laying hens, and the symptoms correlated with the fatty acid profile of total phospholipids. Overall, the findings revealed that mycotoxin exposure, even at the EU-recommended limits, induced lipid peroxidation in the liver, which led to changes in fatty acid composition, matched with tissue damage. [ABSTRACT FROM AUTHOR]

A Co‐catalyzed peroxidation of cyclic β‐dicarbonyls (cyclic 1,3‐diketones, 4‐hydroxy‐2(5H)‐furanones and Meldrum's acids) with TBHP has been disclosed. A series of the alkylperoxy derivatives of 4‐hydroxy‐2(5H)‐furanones and Meldrum's acids were synthesized in moderate to good yields (13–86 %). The functionalization of 4‐hydroxy‐2(5H)‐furanones by the tBuOO group was performed with high selectivity in the presence of the cocktail of reactive oxidizing species, including metal and radical intermediates. The key species in the peroxidation process are probably the tert‐butylperoxy radical or its Co(III) complex, which are generated from the Co(II)/TBHP system. Cycle cleavage, which would be expected for cyclic β‐dicarbonyls based on previous reports, was observed to a large extent only for cyclic 1,3‐diketones. [ABSTRACT FROM AUTHOR]

Bilirubin (BR), a product of heme catabolism, plays a critical role in biological systems. Although increased levels of BR result in hyperbilirubinemia or jaundice, there is increasing evidence that lower concentrations substantially decrease the risk of oxidative stress-mediated diseases due to antioxidant functions of BR. We studied the radical-trapping ability of BR in two model systems, micellar and liposomal, at a broad pH range. At pH < 6.0, BR behaves as a retardant; however, at pH ≥ 6.0, BR becomes strong radical trapping antioxidant, with rate constants for reaction with lipidperoxyl radicals (kinh) within the range from 1.2 × 104 M−1 s−1 to 3.5 × 104 M−1 s−1, and in liposomal system, the activity of BR is comparable to α-tocopherol. This transition is likely facilitated by the ionization of carboxyl groups, leading to a conformational shift in BR and improved solubility/localization at the water/lipid interface. This is the first experimental evidence of the role of pH on the antioxidant activity of bilirubin, and the observed pH-dependent radical-trapping ability of BR holds practical significance, particularly in jaundice treatment where light therapy targets the skin's weakly acidic surface. Minor adjustments toward neutral or alkaline pH can enhance radical-trapping action of BR, thereby mitigating oxidative stress induced with blue or violet light exposure. [ABSTRACT FROM AUTHOR]

Methane photooxidation into methanol offers a practical approach for the generation of high‐value chemicals and the efficient storage of solar energy. However, the propensity for C─H bonds in the desired products to cleave more easily than those in methane molecules results in a continuous dehydrogenation process, inevitably leading to methanol peroxidation. Consequently, inhibiting methanol peroxidation is perceived as one of the most formidable challenges in the field of direct conversion of methane to methanol. This review offers a thorough overview of the typical mechanisms involved radical mechanism and active site mechanism and the regulatory methods employed to inhibit product peroxidation in methane photooxidation. Additionally, several perspectives on the future research direction of this crucial field are proposed. [ABSTRACT FROM AUTHOR]

Simple Summary: Tropical herb extracts, which could be used to provide health benefits, might be an effective strategy to promote benefits for rabbit farming. The present study indicated that the supplementation of rabbit diets with butterfly pea (Clitoria ternatea L.) crude extract had no effect on phagocytic function but did improve digestibility. Modification of the meat color and delayed lipid peroxidation were observed. Supplementation with Clitoria ternatea L. crude extract at 0.5 g/kg body weight could be useful in the production of rabbits for meat consumption, prolonging shelf life by delaying lipid peroxidation. Sixteen 35-day-old male crossbred rabbits (New Zealand white × Thai native breed) with an initial weight of 484 ± 11.3 g were randomly divided into two groups of eight, constituting control and treatment groups. The treatment group was orally administered a crude extract of butterfly pea (Clitoria ternatea L.) at 0.5 g/kg body weight from weaning (at 35 days) to slaughter (at 90 days). The effects on the phagocytic activity of blood polymorphonuclear leukocytes, serum biochemistry, meat quality, muscular lipid peroxidation, the apparent digestibility of dry matter and nutrients, and gut histology were studied. The results revealed that the phagocytic function of circulating leukocytes (75 and 90 days) and alveolar macrophages (90 days) did not differ between the two groups. At slaughter, treated rabbits had lower blood urea nitrogen concentrations and higher liver weight than control rabbits (p < 0.05). After chilling at 4 °C for 24 h, a lower meat pH and the alteration of meat color (brighter, less yellow, lower hue angle, and decreased color saturation) were observed in the treated group (p < 0.05). Furthermore, lipid peroxidation (measured at 3, 5, and 7 storage days) in the meat of treated rabbits was lower than in controls (p < 0.05). The apparent digestibility of organic matter and ether extract (analyzed at 46 days for 4 days) was improved in the treated group (p < 0.05), whereas gut histology was unaffected. In conclusion, butterfly pea extract supplementation did not affect phagocytic function but led to a modification in meat color, delayed lipid peroxidation, and improved digestibility. [ABSTRACT FROM AUTHOR]

We introduced the radical chain transfer reaction into the LPO process to target the propagation step and overcome the sluggish rate of lipid peroxidation, thereby promoting endogenous lipid peroxidation and enhancing therapeutic outcomes. [Display omitted] Lipid peroxidation (LPO), the process of membrane lipid oxidation, is a potential new form of cell death for cancer treatment. However, the radical chain reaction involved in LPO is comprised of the initiation, propagation (the slowest step), and termination stages, limiting its effectiveness in vivo. To address this limitation, we introduce the radical chain transfer reaction into the LPO process to target the propagation step and overcome the sluggish rate of lipid peroxidation, thereby promoting endogenous lipid peroxidation and enhancing therapeutic outcomes. Firstly, radical chain transfer agent (CTA-1)/Fe nanoparticles (CTA-Fe NPs-1) was synthesized. Notably, CTA-1 convert low activity peroxyl radicals (ROO·) into high activity alkoxyl radicals (RO·), creating the cycle of free radical oxidation and increasing the propagation of lipid peroxidation. Additionally, CTA-1/Fe ions enhance reactive oxygen species (ROS) generation, consume glutathione (GSH), and thereby inactivate GPX-4, promoting the initiation stage and reducing termination of free radical reaction. CTA-Fe NPs-1 induce a higher level of peroxidation of polyunsaturated fatty acids in lipid membranes, leading to highly effective treatment in cancer cells. In addition, CTA-Fe NPs-1 could be enriched in tumors inducing potent tumor inhibition and exhibit activatable T 1 -MRI contrast of magnetic resonance imaging (MRI). In summary, CTA-Fe NPs-1 can enhance intracellular lipid peroxidation by accelerating initiation, propagation, and inhibiting termination step, promoting the cycle of free radical reaction, resulting in effective anticancer outcomes in tumor-bearing mice. [ABSTRACT FROM AUTHOR]

The medicinal importance of the genus Daphne L. is related to the richness in the expansive range of different classes of natural products and bioactive phytochemicals, such as coumarins, flavonoids, lignans and different classes of terpenes. The current study reports on the lipid peroxidation effect of diethyl-ether macerate of Daphne mezereum L. flowers and of two coumarins we have isolated from the aqueous subfraction of the crude diethyl-ether extract. All three tested samples, D. mezereum flowers extract (IC50 = 25.1 ± 2.9 mM) and isolated coumarins: umbelliferone (IC50 = 7.1 ± 2.6 mM) and herniarin (IC50 = 19.0 ± 1.3 mM), exhibited notable antioxidative potential in lipid peroxidation assay. None of the samples, however, had an inhibitory effect as pronounced as standardly applied antioxidants Trolox (IC50 = 22 ± 6 μM), caffeic acid (IC50 = 15 ± 3 μM) and quercetin (IC50 = 23 ± 6 μM). Taken altogether, the results of our studies bring forward new data regarding the antioxidant activities of D. mezereum species. [ABSTRACT FROM AUTHOR]

Chronic exposure to potentially toxic elements (PTEs) such as cadmium (Cd) leads to male reproductive toxicity through the generation of oxidative stress. Spirulina Arthrospira maxima (AM) is a cyanobacterium that has been consumed since ancient times for its high nutritional value, and in recent years for its antiviral, hepatoprotective, hypoglycemic, anticancer, and antioxidant effects, among others. This study aimed to evaluate the effects of AM against the damage to reproductive health induced by Cd. A total of 48 10-week-old sexually experienced male Wistar rats were distributed in five groups (n = 8): control; vehicle (tween-water); cadmium chloride (CdCl2) 5 mg/kg; and three doses of AM (100, 200 and 400 mg/kg) + CdCl2 5 mg/kg. All treatments were orally administered once a day for 36 consecutive days. At the end, sexual behavior was evaluated, and semen, testicle, and blood samples were obtained to analyze sperm quality, enzymatic activity, and testosterone levels, respectively. Rats exposed to Cd showed a decrease in sexual behavior, as well as in the quality of reproductive health, and an increase in oxidative stress; while rats exposed simultaneously to AM + Cd showed an improvement in all this parameters. Based on our results, we believe that the mechanism by which AM exerts its effect could be attributed to the presence of phycobiliproteins. These compounds are responsible for exerting an antioxidant effect and chelating effect on elements such as Cd. [ABSTRACT FROM AUTHOR]

Ferroptosis, a regulated cell death hallmarked by excessive lipid peroxidation, is implicated in various (patho)physiological contexts. During ferroptosis, lipid peroxidation leads to a diverse change in membrane properties and the dysre)gulation of ion homeostasis via the cation channels, ultimately resulting in plasma membrane rupture. This review illuminates cellular membrane dynamics and cation handling in ferroptosis regulation. [ABSTRACT FROM AUTHOR]

Under the uncongenial growth condition imposed by salts in the edaphic environment, several biochemical changes take place in plants, which help them to survive under such a hostile environment. In the present study, an attempt has been made to obtain basic information about the effect of salt stress on relative membrane injury, lipid peroxidation content and reactive oxygen species content in isabgol (Plantago ovata Forsk.) genotypes. The changes in relative membrane injury, lipid peroxidation content and reactive oxygen species (ROS) content of P. ovata genotypes viz. GI-2, HI-96, PB-80 and HI-5 were studied under NaCl salt stress at different EC levels viz. control (without salt), 5 and 10 dS/m of nutrient supplemented NaCl salt solutions in sand filled polythene bags during 1st week of November 2022 in the Department of Botany Government College, Hisar. RMI, lipid peroxidation (MDA content) and ROS content of leaves increased with increasing EC levels in all the isabgol genotypes as studied at 58 days after showing. The highest increase in RMI was found in the genotype PB-80 and lowest in the genotype GI-2 at higher (10 dS/m) EC level over control. Increase in lipid peroxidation content which was measured in terms of MDA content was found highest in the genotype PB-80 while the lowest increase was detected in the genotype HI-5 at higher level (10 dS/m) of salt stress over control. Highest enhancement in ROS content of leaves in the genotype PB-80 and lowest increase in the genotype GI-2 was observed at higher (10 dS/m) EC level over control. The relative order of these parameters in various genotypes under salt stress was PB-80>HI-5>HI-96>GI-2. [ABSTRACT FROM AUTHOR]

A total of 224 69-week-old Nick Chick laying hens were allocated to eight treatments with eight replicate cages to investigate the effects of stocking density (SD) and dietary inclusion of different levels of grape waste (GW) on performance, some egg quality traits and yolk oxidative status of laying hens from 69 to 76 weeks of age. The experiment was conducted as a 2×4 factorial arrangement, with two levels of stocking density (3 and 4 hens/cage as normal (NSD) and high stocking density(HSD), respectively) and four dietary levels of GW (0, 1.5, 3 and 4.5 % of diet, as a corn replacement). The results indicated that rearing hens under HSD conditions resulted in a worse feed conversion ratio (FCR) and less egg production than NSD (P < 0.05). Dietary inclusion of GW had no detrimental effect on performance or egg quality traits. Increasing density had deleterious consequences on FCR, egg production, egg weight and egg mass (P < 0.05), while dietary addition of GW, particularly at the level of 4.5% alleviated those negative effects. Egg quality traits (shell weight, resistance and thickness, yolk weight, albumen height and Hague Unit) were significantly not influenced by GW, SD or their interaction. Stocking density did not affect malondialdehyde (a peroxidation indicator) level in egg yolk lipid, while all hens fed GW had lower levels of malondialdehyde than those fed diet without GW (P < 0.05). The interaction between SD and GW level significantly influenced egg albumen pH at 3 and 30 d room storage (P< 0.05). In conclusion, dietary inclusion of up to 4.5 % GW had no deleterious effect on laying hen's egg quality and improved some performance traits and oxidative stability of egg yolk, particularly in hens reared under HSD. Thus, it could be used as a corn replacement in laying hens' diet. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]