Protein Oxidation Research Articles

Cardioprotective action of apocynin in isoproterenol‐induced cardiac damage is mediated through Nrf‐2/HO‐1 signaling pathway

AbstractThis investigation evaluated the therapeutic benefit of apocynin in isoproterenol (ISO)‐induced cardiac damage in rats. ISO‐administered male Wistar rats were treated with apocynin for 2 weeks. Blood plasma and left ventricle of heart tissues were collected and analyzed for oxidative stress‐related parameters such as malondialdehyde (MDA), advanced oxidation protein product (AOPP), and nitric oxide (NO). The activities of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and catalase were also measured. The gene expressions of oxidative stress‐related proteins such as Nrf‐2, HO‐1, and HO‐2 in cardiac tissues were also measured. In silico studies like molecular docking and molecular dynamics were also performed to detect how apocynin interacts with NADPH and nitric oxide synthase at the molecular level. This investigation revealed significant elevation of serum transferase enzymes and creatinine kinase‐Muscle Brain (CK‐MB) activities in ISO‐administered rats compared to the control. Apocynin effectively normalized the serum transferases and CK‐MB activities in the blood of ISO‐stressed rats. Moreover, ISO‐induced elevations of MDA, NO, and AOPP levels were also suppressed by apocynin treatment. Consistently, apocynin restored the reduced SOD and catalase activities in ISO‐administered rats. This restoration of enzyme activity might be due to the increased expression of Nrf‐2 and HO‐1 and reduced expression of iNOS and TNF‐α in ISO‐administered rats. Histological analysis revealed that apocynin treatment ameliorated the mononuclear cell adherence and fibrosis in the cardiac tissue of ISO‐administered rats. Computational studies also support the experimental findings. This study demonstrates that apocynin prevents ISO‐induced cardiac injury not only by preventing inflammation but also by empowering the antioxidant defense system.

Identification of Key Volatile Compounds in Tilapia during Air Frying Process by Quantitative Gas Chromatography-Ion Mobility Spectrometry.

Air frying as a new roasting technology has potential for roasted fish production. In this study, the changes in volatile compounds (VCs) during air frying of tilapia were studied by quantitative gas chromatography-ion mobility spectrometry, followed by the identification of key VCs based on their odor activity value (OAV). There were 34 verified VCs, of which 16 VCs were identified as the key VCs with OAV ≥ 1. Most of the VCs were improved by air frying and peaked at 20 min. During the air frying, the total sulfhydryl content markedly decreased, while the protein carbonyl and MDA content significantly increased, suggesting the enhancement in the oxidation of lipids and proteins. The correlation network among the chemical properties and key VCs was constructed. The change in total sulfhydryl, protein carbonyl, and MDA showed significant correlation with most of the key VCs, especially 2-methyl butanal, ethyl acetate, and propanal. The results indicated that the oxidation of lipids and proteins contributed the most to the flavor improvement in air-fried tilapia. This study provides a crucial reference for the volatile flavor improvement and pre-cooked product development of roasted tilapia.

Acute cardiorenal dysfunctions induced by isoprenaline in Wistar rats: Mitigating potential of Juglans regia hull extract

The present study aimed to determine the attenuating properties of Juglans regia hull extract (JRHE) in mitigating isoprenaline (ISO) induced cardiorenal dysfunctions in Wistar rats. Thirty adult Wistar rats were randomly allocated to five groups with six animals in each group. Group I served as control; group II animals were administered ISO and group III received JRHE alone whereas group IV and V received JRHE and quercetin along with ISO, respectively. Administration of ISO in rats induced cardiac and renal tissue damage as reflected by significantly (p < 0.05) increased plasma activities of creatine kinase-myocardial band, lactate dehydrogenase, acetylcholinesterase, arylesterase, blood urea nitrogen, creatinine along with altered antioxidant biomarkers viz. total antioxidant status, total thiols, superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and increased (p < 0.05) lipid and protein peroxidation in cardiac and renal tissues. Histopathological findings corroborated that ISO has inflicted significant damage on cardiac and renal tissues. Repeated administration of JRHE significantly (p < 0.05) reduced the severity of ISO-induced alterations in blood, cardiac and renal biomarkers. In addition to restoring the levels of altered cardio-renal antioxidant enzymes, JRHE also ameliorated histopathological lesions in cardiac and renal tissues in ISO-treated rats.

Impact of roasting time on the color, protein, water distribution and key volatile compounds of pork

The study aimed to determine the changes in physical and chemical indicators in pork during the roasting process and establish predictive models for industrial intelligent production in the future, the effects of roasting times (0–15 min) on the dynamic changes in the surface color, water, protein and the volatile compounds in pork were investigated. The results showed that during the roasting process, the L* value increased firstly (0–3 min) and then decreased (3–15 min), the a* value decreased firstly (0–12 min) and then increased (12–15 min), while the b* value increased (0–15 min). A total of 29 volatile compounds were identified by gas chromatography–mass spectrometry, 11 volatile differentiators were identified by partial least squares-discriminant analysis, and 14 key volatile compounds were selected by odor activity values analysis. The total water content significantly decreased and the water in meat migrated from high degrees of freedom to low degrees of freedom. Roasting for 6 min was a key turning point in the changes of the α-helix, β-sheet and random coil. In addition, SDS-PAGE analysis, and the changes in the contents of carbonyl, total and free sulfhydryl verified proteins oxidation in the pork during the roasting process.

Effects of intermittent exposure to hypobaric hypoxia and cold on skeletal muscle regeneration: Mitochondrial dynamics, protein oxidation and turnover

Muscle injuries and the subsequent regeneration events compromise muscle homeostasis at morphological, functional and molecular levels. Among the molecular alterations, those derived from the mitochondrial function are especially relevant. We analysed the mitochondrial dynamics, the redox balance, the protein oxidation and the main protein repairing mechanisms after 9 days of injury in the rat gastrocnemius muscle. During the recovery rats were exposed to intermittent cold exposure (ICE), intermittent hypobaric hypoxia (IHH), and both simultaneous combined stimuli. Non-injured contralateral legs were also analysed to evaluate the specific effects of the three environmental exposures. Our results showed that ICE enhanced mitochondrial adaptation by improving the electron transport chain efficiency during muscle recovery, decreased the expression of regulatory subunit of proteasome and accumulated oxidized proteins. Exposure to IHH did not show mitochondrial compensation or increased protein turnover mechanisms; however, no accumulation of oxidized proteins was observed. Both ICE and IHH, when applied separately, elicited an increased expression of eNOS, which could have played an important role in accelerating muscle recovery. The combined effect of ICE and IHH led to a complex response that could potentially impede optimal mitochondrial function and enhanced the accumulation of protein oxidation. These findings underscore the nuanced role of environmental stressors in the muscle healing process and their implications for optimizing recovery strategies.

Licochalcone D from Glycyrrhiza uralensis Improves High-Glucose-Induced Insulin Resistance in Hepatocytes.

This study investigated the therapeutic potential of licochalcone D (LicoD), which is derived from Glycyrrhiza uralensis, for improving glucose metabolism in AML12 hepatocytes with high-glucose-induced insulin resistance (IR). Ultra-high-performance liquid chromatography-mass spectrometry revealed that the LicoD content of G. uralensis was 8.61 µg/100 mg in the ethanol extract (GUE) and 0.85 µg/100 mg in the hot water extract. GUE and LicoD enhanced glucose consumption and uptake, as well as Glut2 mRNA expression, in high-glucose-induced IR AML12 cells. These effects were associated with the activation of the insulin receptor substrate/phosphatidylinositol-3 kinase signaling pathway, increased protein kinase B α phosphorylation, and suppression of gluconeogenesis-related genes, such as Pepck and G6pase. Furthermore, GUE and LicoD promoted glycogen synthesis by downregulating glycogen phosphorylase. Furthermore, LicoD and GUE mitigated the downregulated expression of mitochondrial oxidative phosphorylation proteins in IR hepatocytes by activating the PPARα/PGC1α pathway and increasing the mitochondrial DNA content. These findings demonstrate the potential of LicoD and GUE as therapeutic options for alleviating IR-induced metabolic disorders by improving glucose metabolism and mitochondrial function.

The long non-coding RNA ROSALIND protects the mitochondrial translational machinery from oxidative damage.

Upregulation of mitochondrial respiration coupled with high ROS-scavenging capacity is a characteristic shared by drug-tolerant cells in several cancers. As translational fidelity is essential for cell fitness, protection of the mitochondrial and cytosolic ribosomes from oxidative damage is pivotal. While mechanisms for recognising and repairing such damage exist in the cytoplasm, the corresponding process in the mitochondria remains unclear.By performing Ascorbate PEroXidase (APEX)-proximity ligation assay directed to the mitochondrial matrix followed by isolation and sequencing of RNA associated to mitochondrial proteins, we identified the nuclear-encoded lncRNA ROSALIND as an interacting partner of ribosomes. ROSALIND is upregulated in recurrent tumours and its expression can discriminate between responders and non-responders to immune checkpoint blockade in a melanoma cohort of patients. Featuring an unusually high G content, ROSALIND serves as a substrate for oxidation. Consequently, inhibiting ROSALIND leads to an increase in ROS and protein oxidation, resulting in severe mitochondrial respiration defects. This, in turn, impairs melanoma cell viability and increases immunogenicity both in vitro and ex vivo in preclinical humanised cancer models. These findings underscore the role of ROSALIND as a novel ROS buffering system, safeguarding mitochondrial translation from oxidative stress, and shed light on potential therapeutic strategies for overcoming cancer therapy resistance.

Effects of uric acid on oxidative stress in vascular smooth muscle cells.

Hyperuricemia during hypertension is associated with aberrant vascular functions and increased oxidative stress, which affects endothelial dysfunction. Nevertheless, the molecular mechanisms underlying the effects of uric acid on vascular smooth muscle cells (VSMCs) through oxidative stress remain unclear. The aim of the present study was to investigate the dose- and time-dependent effects of uric acid on oxidative stress and p53 protein expression in VSMCs. VSMCs were incubated with various concentrations of uric acid (0-50 mg/dl) for different time periods (1-24 h). Thiobarbituric acid reactive substances (TBARs), protein carbonylation and nitric oxide (NO) levels were determined using appropriate assay kits. Superoxide anion release was detected using the Görlach method. Western blotting was performed to determine the protein expression levels of p53. The findings demonstrated that the application of uric acid led to an increase in protein carbonylation and superoxide anion levels while causing a decrease in NO levels. Conversely, no significant effect was observed on TBARS levels. Additionally, it was observed that high concentrations of uric acid suppressed p53 expression at 6, 12 and 24 h. The present study provided evidence that the influence of uric acid on oxidative stress was more closely associated with time than dose; however, not all effects observed were strictly time-dependent.

The anti-angiogenic, anti-inflammatory and anticoagulant potential of a polysaccharide extracted from the brown alga Cystoseira humilis

The present study aimed to evaluate the properties of a sulfated polysaccharide (PSCH) extracted from the brown alga Cystoseira humilis. We analyzed the chemical composition, anti-angiogenesis activities, anticoagulant, and anti-inflammatory effects of the PSCH, using various techniques encompassing UV–visible spectroscopy, fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (X-RD), scanning electron microscopy (SEM), steric exclusion chromatography (SEC) and high-performance liquid chromatography coupled to refractive index detector (HPLC-RID). The study found that PSCH was a sulfated heteropolysaccharide consisting of glucuronic acid, arabinose, galacturonic acid, xylose and fructose, and has a semi-crystalline nature with a molecular weight of about 379.44 kDa. The PSCH contains 41.77 % carbohydrates, 12.33 % proteins, and 4.59 % sulfates. The PSCH fraction has anti-angiogenic potential highlighted through assays on the chorioallantoic membrane, where vascular branching was inhibited by about 41.65 % and 61.38 % at concentrations of 50 and 100 μg/egg, respectively, compared to the untreated group. PSCH displayed an anti-edematous effect in vivo by reducing malondialdehyde and advanced oxidation protein products in paw tissue after five hours of carrageenan injection. When rats were co-treated with PSCH, there was evidence of a significant increase in antioxidant enzyme activity (superoxide dismutase, glutathione peroxidase, and glutathione) in edematous paw tissues compared to untreated rats. Furthermore, PSCH significantly influenced hematological parameters and the rate of anti-inflammatory serum protein fractions compared to the inflamed group. Interestingly, PSCH may exhibit anticoagulant properties by extending activated partial thrombosis time, thrombin time and prothrombin time. The present study has shown that Cystoseira humilis polysaccharides have antioxidant, anti-angiogenic, anti-inflammatory, and anti-coagulant properties, making them suitable for therapeutic purposes.

Thermal-induced interactions between soy protein isolate and malondialdehyde: Effects on protein digestibility, structure, and formation of advanced lipoxidation end products

Thermally processed lipid- and protein-rich foods have sparked widespread concern since they may degrade food nutrition and even risk food safety. This study investigated soy protein isolate (SPI) alterations of digestibility and structure, as well as the formation of potentially hazardous chemicals, i.e., advanced lipoxidation end products (ALEs), after interacting with malondialdehyde (MDA, a lipid oxidation product) under high-temperature cooking conditions (100–180 °C, up to 60 min). In-vitro protein digestion of the SPI-MDA mixtures suggested that their room-temperature interactions damaged SPI digestibility, and increasing the temperature and the duration of the thermal treatment exacerbated the adverse effects. Protein oxidation, covalent aggregation of subunits, and changes in secondary and tertiary structures were revealed using thiol quantification, gel electrophoresis, fluorescence spectroscopy, and circular dichroism (CD) spectra, which could explain reduced protein digestibility. High-resolution mass spectrometry (HRMS) identified seven non-crosslinked ALEs and two crosslinked ALEs. Increased MDA concentrations promoted the generation of ALEs. Moreover, the acrolein-derived ALEs with reactive carbonyl groups were prone to further reacting into crosslinked ALEs, potentially responsible for the subunit aggregation.

PSVI-14 Effects of poor maternal nutrition during gestation on first generation offspring oxidative status in skeletal muscle

Abstract Poor maternal nutrition (restricted- and over-nutrition) during gestation negatively impacts offspring pre- and post-natal growth. Previous work has identified decreased muscle mass and increased adiposity, leading to poor quantity and quality of animal protein products. Alterations in oxidative status, such as the imbalance of antioxidant activity and the production of free radicals, can result in oxidative stress damaging lipid membranes, proteins, and DNA. Changes in oxidative status may contribute to the poor growth outcomes observed in offspring from poorly nourished dams. Therefore, the objective of this research was to determine the effects of poor maternal nutrition during gestation on the oxidative status in offspring skeletal muscle in sheep. We hypothesized that offspring of restricted- and over-fed ewes would have decreased antioxidant activity and increased products of oxidative stress in skeletal muscle. To test this hypothesis, multiparous Dorset ewes (n = 46) pregnant with twins were fed 100% (CON), 60% (RES), or 140% (OVER) of total nutrient requirements (NRC) from d 30 of gestation until parturition. Following parturition, ewes were fed a control diet throughout lactation. At d 282 of age semitendinosus (STN) samples were collected from rams at necropsy, and at d 284 of age muscle biopsies from STN were collected from ewes. Data were analyzed in SAS using PROC MIXED with fixed effects of maternal diet and offspring sex. Data were considered significant at P ≤ 0.05. The activity of the endogenous antioxidant superoxide dismutase (SOD) was decreased by 45% and 33% in RES and OVER offspring, respectively, compared with CON (P ≤ 0.01). Offspring sex did not alter STN SOD activity (P = 0.35). Muscle glutathione peroxidase (GPx) activity was decreased in RES offspring by 20% compared with CON (P ≤ 0.04), but neither differed from OVER offspring (P ≥ 0.24). Ewes had 34% greater GPx activity compared with rams (P &amp;lt; 0.0001). Offspring from RES and OVER ewes had 77% and 87% greater concentrations of malondialdehyde (MDA), a marker of lipid peroxidation, when compared with CON (P &amp;lt; 0.0001). Ewes had 29% greater MDA concentrations compared with rams (P = 0.05). Protein carbonyl (PC), a marker of protein oxidation, concentrations were 36% and 38% greater in RES and OVER offspring, respectively, compared with CON (P ≤ 0.01). The decrease in antioxidant activities and increase in products of protein and lipid oxidation in offspring from poorly nourished dams suggests dysregulation in skeletal muscle oxidative status that may contribute to the negative consequences observed in offspring. Future work should focus on determining the mechanistic role of skeletal muscle oxidative stress in the decreased quantity and quality of animal protein products and identifying potential strategies to mitigate alterations in oxidative status as a result of poor maternal nutrition during gestation.

An Overview of Interactions between Goat Milk Casein and Other Food Components: Polysaccharides, Polyphenols, and Metal Ions.

Casein is among the most abundant proteins in milk and has high nutritional value. Casein's interactions with polysaccharides, polyphenols, and metal ions are important for regulating the functional properties and textural quality of dairy foods. To improve the functional properties of casein-based foods, a deep understanding of the interaction mechanisms and the influencing factors between casein and other food components is required. This review started by elucidating the interaction mechanism of casein with polysaccharides, polyphenols, and metal ions. Thermodynamic incompatibility and attraction are the fundamental factors in determining the interaction types between casein and polysaccharides, which leads to different phase behaviors and microstructural types in casein-based foods. Additionally, the interaction of casein with polyphenols primarily occurs through non-covalent (hydrogen bonding, hydrophobic interactions, van der Waals forces, and ionic bonding) or covalent interaction (primarily based on the oxidation of proteins or polyphenols by enzymatic or non-enzymatic (alkaline or free radical grafting) approaches). Moreover, the selectivity of casein to specific metal ions is also introduced. Factors affecting the binding of casein to the above three components, such as temperature, pH, the mixing ratio, and the fine structure of these components, are also summarized to provide a good foundation for casein-based food applications.

Oxidative Stress and Age-Related Tumors.

Oxidative stress is the result of the imbalance between reactive oxygen and nitrogen species (RONS), which are produced by several endogenous and exogenous processes, and antioxidant defenses consisting of exogenous and endogenous molecules that protect biological systems from free radical toxicity. Oxidative stress is a major factor in the aging process, contributing to the accumulation of cellular damage over time. Oxidative damage to cellular biomolecules, leads to DNA alterations, lipid peroxidation, protein oxidation, and mitochondrial dysfunction resulting in cellular senescence, immune system and tissue dysfunctions, and increased susceptibility to age-related pathologies, such as inflammatory disorders, cardiovascular and neurodegenerative diseases, diabetes, and cancer. Oxidative stress-driven DNA damage and mutations, or methylation and histone modification, which alter gene expression, are key determinants of tumor initiation, angiogenesis, metastasis, and therapy resistance. Accumulation of genetic and epigenetic damage, to which oxidative stress contributes, eventually leads to unrestrained cell proliferation, the inhibition of cell differentiation, and the evasion of cell death, providing favorable conditions for tumorigenesis. Colorectal, breast, lung, prostate, and skin cancers are the most frequent aging-associated malignancies, and oxidative stress is implicated in their pathogenesis and biological behavior. Our aim is to shed light on the molecular and cellular mechanisms that link oxidative stress, aging, and cancers, highlighting the impact of both RONS and antioxidants, provided by diet and exercise, on cellular senescence, immunity, and development of an antitumor response. The dual role of ROS as physiological regulators of cell signaling responsible for cell damage and diseases, as well as its use for anti-tumor therapeutic purposes, will also be discussed. Managing oxidative stress is crucial for promoting healthy aging and reducing the risk of age-related tumors.

Evaluation of the water state and protein characteristics of Tibetan pork under the storage conditions of modified atmosphere packaging: Effect of oxygen concentration

To explore the changes in water status and protein characteristics of Tibetan pork (TP) under modified atmosphere packaging (MAP) with different oxygen concentrations compared to Duroc×Landrace×Yorkshire pork (DLY), the water holding capacity (WHC), water distribution, protein oxidation, and conformation of both types were determined. Results indicate that under MAP, TP pork and DLY pork exhibited higher water retention and lower protein oxidation compared to air packaging. However, with increased oxygen concentration in the MAP, protein oxidation intensified, leading to reduced WHC in the pork. Compared to DLY pork, TP pork in different packaging conditions maintained the integrity of protein secondary and tertiary structures, reducing protein cross-linking aggregation. The lower content of P3 in the two-dimensional relaxation spectra, shorter T1 and T2 relaxation times, and higher proton density suggest better water retention properties in Tibetan pork. These findings support the development of long-distance preservation and transportation technologies for TP pork.

Effect of flaxseed oil cyclolinopeptides on lipid oxidation, protein oxidation, and lipid profile during in vitro digestion of high-fat beef

This study investigated the influence of flaxseed oil cyclolinopeptides (CLs) on lipid and protein oxidation during high-fat meat digestion. Fourteen CLs were identified in flaxseed oil through UHPLC-ESI-QTOF-MS/MS, with dominant CLA, CLB, CLE, and CLM. During in vitro digestion, CLs inhibited lipid oxidation products (lipid hydroperoxide, Malondialdehyde, and 4-hydroxynonenal) and protein carbonylation. Compared to other groups, the lipid (16.28 ± 0.35) and protein (17.5 ± 0.6) oxidation was significantly inhibited, and antioxidant activity was remarkably increased when the CLs content reached 200 mg/kg. Through untargeted lipidomic analysis using Q-Exactive, it was observed that CLs mitigated the formation of oxidized triglycerides (OxTG) products and enhanced the hydrolysis of lipids to generate sphingolipid and polyunsaturated fatty-acids enriched glycerophospholipids imparting nutritional value to meat. Electron spin-resonance and fluorescence quenching showed that primary radicals such as alkyl and alkoxy radicals during high-fat meat digestion with flaxseed oil CLs significantly mitigate their formation. These findings collectively indicate that consuming CLs enriched flaxseed oil could reduce lipid oxidation and enhance the nutritional value of high-fat meat during digestion.

HOCl forms lipid N-chloramines in cell membranes of bacteria and immune cells

Neutrophils orchestrate a coordinated attack on bacteria, combining phagocytosis with a potent cocktail of oxidants, including the highly toxic hypochlorous acid (HOCl), renowned for its deleterious effects on proteins. Here, we examined the occurrence of lipid N-chloramines in vivo, their biological activity, and their neutralization. Using a chemical probe for N-chloramines, we demonstrate their formation in the membranes of bacteria and monocytic cells exposed to physiologically relevant concentrations of HOCl. N-chlorinated model membranes composed of phosphatidylethanolamine, the major membrane lipid in Escherichia coli and an important component of eukaryotic membranes, exhibited oxidative activity towards the redox-sensitive protein roGFP2, suggesting a role for lipid N-chloramines in protein oxidation. Conversely, glutathione a cellular antioxidant neutralized lipid N-chloramines by removing the chlorine moiety. In line with that, N-chloramine stability was drastically decreased in bacterial cells compared to model membranes. We propose that lipid N-chloramines, like protein N-chloramines, are involved in inflammation and accelerate the host immune response.

Elucidating the bacterial inactivation mechanism by argon cold atmospheric pressure plasma jet through spectroscopic and imaging techniques.

This study aims to assess the potential bacterial inactivation pathway triggered by argon (Ar) cold atmospheric pressure plasma jet (CAPJ) discharge using spectroscopic and imaging techniques. Electrical and reactive species of the Ar CAPJ discharge was characterized. The chemical composition and morphology of bacteria pre- and post-CAPJ exposure were assessed using Fourier transform infrared (FTIR), Raman micro-spectroscopy, and transmission electron microscopy (TEM). A greater than 6 log reduction of E. coli and S. aureus was achieved within 60 and 120 s of CAPJ exposure, respectively. Extremely low D- values (< 20 s) were recorded for both the isolates. The alterations in the FTIR spectra and Raman micro-spectra signals of post-CAPJ exposed bacteria revealed the degree of destruction at the molecular level, such as lipid peroxidation, protein oxidation, bond breakages, etc. Further, TEM images of exposed bacteria indicated the incurred damages on cell morphology by CAPJ reactive species. Also, the inactivation process varied for both isolates, as evidenced by the correlation between the inactivation curve and FTIR spectra. It was observed that the identified gas-phase reactive species, such as Ar I, O I, OH•, NO+, OH+, NO2-, NO3-, etc. played a significant role in bacterial inactivation. This study clearly demonstrated the effect of CAPJ exposure on bacterial cell morphology and molecular composition, illuminating potential bacterial inactivation mechanisms.

Ascorbic acid-containing compound efficacy in ischemic brain damage

Introduction: Ischemic brain injury remains one of the main causes of disability and mortality worldwide. Protection of cellular population, depriving from oxygen supply and nutrients, is of extreme importance for further both clinical and health outcomes of timely implemented intravascular intervention. The aim: to assess anti-ischemic activity of 3-hydroxypyridine ascorbate in the in vitro and in vivo models of brain cell and tissue response to ischemia and reoxygenation. Materials and Methods: 3-hydroxypyridine ascorbate (laboratory code 3-EA) was assessed as chemical substance (purity 99.8%) diluted in sterile phosphate-buffered saline. Intracellular Ca2+ response to glutamate excitotoxicity (GluTox), ischemia and reoxygenation as well as cellular viability was evaluated on NMRI murine fresh cortical neuro-glial cell culture incubated with 2-EA by registering intracellular Fura-2 and propidium iodide fluorescence respectively. Expression of apoptosis regulating genes BCL-2, STAT3, SOCS3, inflammation regulating genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β и TNFα, and genes MAO-A and MAO-B was determined by real-time PCR. The substance neuroprotection was studied in male Sprague-Dawley rats with intraluminal middle cerebral artery (MCA) occlusion/reperfusion treated with 18 mg/kg of 2-EA along with neurological deficiency evaluation and morphological assessment of brain sections. Results: Preincubation of cortical cells with 10-100 μM of 3-EA leads to inhibition of [Ca2+]i in cytosol of neurons and astrocytes under GluTox and oxygen-glucose deprivation (OGD) conditions. Reducing [Ca2+]i inhibits necrotic cell death in an acute experiment. Incubation of cerebral cortex cells with 3-EA leads to an overexpression of anti-apoptotic genes BCL-2, STAT3, SOCS3, along with downregulation of genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β and TNFα. Intraperitoneal administration of 3-EA reduces the volume of necrotic areas, perinecrotic edema, cell damage, and neurological deficits in rats with MCA occlusion. Conclusion: 3-EA dose-dependently suppresses the death of cerebral cortex cells under the excitotoxic effects of glutamate and ischemia/reoxygenation. Cell-protective effect of 3-EA involves changes in the basal and ischemia/reoxygenation-induced expression of genes encoding anti-apoptotic proteins and oxidative status proteins, which leads to inhibition of the late irreversible stages of apoptosis. A course administration of 3-hydroxypyridine ascorbate at a dose of 18 mg/kg per day reduces the severity of damage both by preserving the population of neurons in the penumbra zone and by limiting the local stress response.

Immune response for acute Aeromonas hydrophila infection in two distinct color morphs of northern snakehead, Channa argus

To compare and analyze the differences in immunological response between the two color morphs of Channa argus, a fish cohort was divided into four groups: black C argus + PBS (B-PBS), black C argus + Aeromonas hydrophila (B-Ah), white C. argus + PBS (W-PBS), and white C. argus + A hydrophila (W-Ah). The B-PBS and W-PBS groups received 100 μL PBS, while the B-Ah and W-Ah groups received 3.6 × 105 CFU/mL A. hydrophila in the same volume. The death rate in each group was noted, changes in plasma biochemical indicators and the expression of liver immune-related genes were examined, and transcriptome techniques were used to compare the differences between the two colors of C. argus following stress. No mortality occurred in the B-PBS and W-PBS groups. Mortality in the W-Ah and B-Ah groups showed an upward and then downward trend after A. hydrophila injection. The highest mortality occurred within 24 h and was higher in the W-Ah group than in the B-Ah group. MDA levels in the B-Ah and W-Ah groups increased and then decreased, while SOD and T-AOC showed the reverse tendency. The W-Ah and W-PBS groups differed significantly in MDA at 3, 12, and 24 h, SOD from 6 to 96 h, and T-AOC between 6 and 48 h. Plasma MDA and T-AOC levels at 12 h and SOD levels at 24 and 48 h differed significantly between the B-PBS and B-Ah groups. In both the W-Ah and B-Ah groups, the expression levels of IL-1β and IL-8 in the liver showed a temporal pattern with an initial increase followed by a decrease, reaching peak levels after 24 h, while IL-10 showed the reverse pattern. Transcriptome analysis of the liver revealed significant differences between the two C. argus colors. Differential genes in black C. argus were mainly enriched in steroid biosynthesis, glycolysis/gluconeogenesis, and glutathione and propanoate metabolism pathways 24 h after infection. In contrast, differential genes in white C. argus were mainly enriched in pathways such as oxidative phosphorylation, pancreatic secretion, and protein digestion and absorption 24 h after infection. After A. hydrophila infection, white C. argus had higher mortality, more severe oxidative stress and inflammatory responses, and lower antioxidant capacity than black C. argus.

Effect of onion skin powder on color, lipid, and protein oxidative stability of premade beef patty during cold storage

The impact of premade beef patty (BBP) with red onion skin powder (OSP) at 0, 1, 2, and 3% levels on color, lipid, and protein oxidative stability, and infection degree of microorganisms during cold storage was investigated. The objective was to determine the effect of color by L*, a*, b*, and the content of MetMb. The inhibitory effect of OSP on the oxidation of lipid and protein was studied based on TBARS and the carbonyl content of protein in samples at different storage times. TVB-N content was used to characterize the degree of infection of microorganisms and their effect on meat quality. The results showed that the addition of OSP reduced the pH, L *, a*, and b * values of BBP, and improved the hardness, springiness, gumminess, and cohesiveness of BBP, but had no significant effect on the chewiness of BBP (p > 0.05). After 12 days of storage, the carbonyl group and TBARS content in the BBP supplemented with 3%OSP was significantly lower than that in the control group (p < 0.05). Furthermore, the addition of OSP significantly inhibited the TVB-N increase during beef patty storage. These results indicated that OSP has a good research prospect as a natural antioxidant or preservative.