Marker Of Protein Oxidation Research Articles

Exploring the anti‑oxidative mechanisms of Rhodiola rosea in ameliorating myocardial fibrosis through network pharmacology and in vitro experiments.

Myocardial fibrosis (MF) significantly compromises cardiovascular health by affecting cardiac function through excessive collagen deposition. This impairs myocardial contraction and relaxation and leads to severe complications and increased mortality. The present study employed network pharmacology and in vitro assays to investigate the bioactive compounds of Rhodiola rosea and their targets. Using databases such as HERB, the Encyclopedia of Traditional Chinese Medicine, Pubchem, OMIM and GeneCards, the present study identified effective components and MF‑related targets. Network analysis was conducted with Cytoscape to develop a Drug‑Ingredient‑Target‑Disease network and the STRING database was utilized to construct a protein‑protein interaction network. Key nodes were analyzed for pathway enrichment using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Molecular interactions were further explored through molecular docking techniques. The bioactivity of salidroside (SAL), the principal component of Rhodiola rosea, against MF was experimentally validated in H9c2 cardiomyocytes treated with angiotensin II and assessed for cell viability, protein expression and oxidative stress markers. Network pharmacology identified 25 active ingredients and 372 targets in Rhodiola rosea, linking SAL with pathways such as MAPK, EGFR, advanced glycosylation end products‑advanced glycosylation end products receptor and Forkhead box O. SAL showed significant interactions with core targets such as albumin, IL6, AKT serine/threonine kinase 1, MMP9 and caspase‑3. In vitro, SAL mitigated AngII‑induced increases in collagen I and alpha smooth muscle actin protein levels and oxidative stress markers, demonstrating dose‑dependent effectiveness in reversing MF. SAL from Rhodiola rosea exhibited potent anti‑oxidative properties that mitigated MF by modulating multiple molecular targets and signaling pathways. The present study underscored the therapeutic potential of SAL in treating oxidative stress‑related cardiovascular diseases.

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 < 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 < 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.

Cellular responses following ex vivo lung exposure to the nerve agent VX – Potential for additional treatment targets?

Following inhalation exposure to organophosphorus nerve agents, symptoms rapidly develop and severe respiratory symptoms, such as bronchorrhea and bronchoconstriction are the leading causes of lethality. Nerve agent-induced lung injury is little investigated and the standard treatment for symptomatic relief targets the enzyme acetylcholinesterase and muscarinic acetylcholine and GABAergic receptors. In the present study, cellular responses in lung tissue during the acute (40 min) and extended phase (24 h) following severe exposure to the nerve agent VX have been investigated using an ex vivo rat precision-cut lung slice model including electrostimulation to induce a cholinergic response. Changes in protein amount, cell viability, together with, inflammatory and oxidative stress markers have been determined in both the lung tissue and incubation medium.During the acute phase, VX caused significantly increased airway contraction and decreased airway relaxation. Five micromolar of VX did not affect the sample protein levels and cell viability in lung tissue. Among seven markers of cellular responses investigated in the lung tissue, increased levels of heme oxygenase-1 and matrix metalloproteinase-9 together with decreased levels of glutathione in the incubation medium were observed in the acute phase following VX-exposure compared to electrostimulation only. No difference in cellular response was observed following VX-exposure for 24 h compared to the air control. In comparison, LPS-exposure resulted in time-dependent changes in all markers of inflammation and oxidative response.In conclusion, the present study demonstrated VX-specific patterns of oxidative responses in the lung, as well as, signs of inflammatory response and remodelling of extracellular matrix. These potential mechanisms of tissue injury should be further investigated for their potential as additional therapeutic targets during the acute phase of intoxication.

Oxidative Modifications of Proteins and Lipids of Dried Semen, Urine, and Saliva Stains as a Function of Age in Forensic Context

Knowledge of the time of deposition is pivotal in forensic investigations. Recent studies show that changes in intrinsic fluorescence over time can be used to estimate the age of body fluids. These changes have been attributed to oxidative modifications caused by protein–lipid interactions. This pilot study aims to explore the impact of these modifications on body fluid fluorescence, enhancing the protein–lipid model system for age estimation. Lipid and protein oxidation markers, including protein carbonyls, dityrosine, advanced glycation end-products (AGEs), malondialdehyde (MDA), and 4-hydroxynonenal (HNE), were studied in aging semen, urine, and saliva over 21 days. Surface plasmon resonance imaging (SPRi), enzyme-linked immunosorbent assay (ELISA), and fluorescence spectroscopy were applied. Successful detection of AGE, dityrosine, MDA, and HNE occurred in semen and saliva via SPRi, while only dityrosine was detected in urine. Protein carbonyls were measured in all body fluids, but only in saliva was a significant increase observed over time. Additionally, protein fluorescence loss and fluorescent oxidation product formation were assessed, showing significant decreases in semen and saliva, but not in urine. Although optimization is needed for accurate quantification, this study reveals detectable markers for protein and lipid oxidation in aging body fluids, warranting further investigation.

Analysis of quality-related proteins in golden pompano (Trachinotus ovatus) fillets with modified atmosphere packaging under superchilling storage

Here, we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage. Tandem mass tags (TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between protein changes and quality characteristics of modified atmosphere packaging (MAP) fillets during superchilling (-3 ℃) storage. Scanning electron microscopy was used to show that the muscle histology microstructure of fillets was damaged to varying degrees, and low-field nuclear magnetic resonance was used to find that the immobile water and free water in the muscle of fillets changed significantly. Total sulfhydryl content, TCA-soluble peptides and Ca2+-ATPase activity also showed that the fillet protein had a deterioration by oxidation and denaturation. The Fresh (FS), MAP, and air packaging (AP) groups were set. Total of 150 proteins were identified as differential abundant proteins (DAPs) in MAP/FS, while 209 DAPs were in AP/FS group. The KEGG pathway analysis indicated that most DAPs were involved in binding proteins and protein turnover. Correlation analysis found that 52 DAPs were correlated with quality traits. Among them, 8 highly correlated DAPs are expected to be used as potential quality markers for protein oxidation and water-holding capacity. These results provide a further understanding of the muscle deterioration mechanism of packaging golden pompano fillets during superchilling.

Antioxidant potential of pomegranate peel and acorn cupule extracts: A comparative analysis in simulated In vitro digestion of uncured dry sausages

The study investigated the effects of incorporating quercetin and varying amounts of polyphenols (0, 1.25, and 12.5 mg/digestion) from two natural sources, pomegranate peel (PPE) and acorn cupule (ACE), on lipid and protein oxidation during gastrointestinal digestion of uncured dry sausages. Quercetin significantly reduced levels of lipid and protein oxidation markers, as well as the levels of PPE and ACE added, compared to the control. The antioxidant effects of PPE and ACE were dose-dependent. The greater the amount of added polyphenols (12.5 vs. 1.25 mg/digest), the lower the oxidation. ACE exhibited a greater antioxidant effect than PPE, reducing the formation of malondialdehyde in the digests. Conversely, PPE demonstrated a stronger antioxidant effect than ACE in terms of protein oxidation, decreasing the formation of carbonyl groups in the digests. Our study underscores the critical need to address the potential health risks associated with consuming uncured dry sausages, emphasizing the remarkable antioxidant capabilities of pomegranate peel extract and acorn cupule extract, which offer significant protective effects against lipid and protein oxidation during digestion, highlighting the importance of promoting consumer awareness regarding antioxidant-rich dietary choices to mitigate harmful compound formation.

Perineuronal nets are phagocytosed by MMP-9 expressing microglia and astrocytes in the SOD1G93A ALS mouse model.

Perineuronal nets (PNNs) are an extracellular matrix structure that encases excitable neurons. PNNs play a role in neuroprotection against oxidative stress. Oxidative stress within motor neurons can trigger neuronal death, which has been implicated in amyotrophic lateral sclerosis (ALS). We investigated the spatio-temporal timeline of PNN breakdown and the contributing cellular factors in the SOD1G93A strain, a fast-onset ALS mouse model. This was conducted at the presymptomatic (P30), onset (P70), mid-stage (P130), and end-stage disease (P150) using immunofluorescent microscopy, as this characterisation has not been conducted in the SOD1G93A strain. We observed a significant breakdown of PNNs around α-motor neurons in the ventral horn of onset and mid-stage disease SOD1G93A mice compared with wild-type controls. This was observed with increased numbers of microglia expressing matrix metallopeptidase-9 (MMP-9), an endopeptidase that degrades PNNs. Microglia also engulfed PNN components in the SOD1G93A mouse. Further increases in microglia and astrocyte number, MMP-9 expression, and engulfment of PNN components by glia were observed in mid-stage SOD1G93A mice. This was observed with increased expression of fractalkine, a signal for microglia engulfment, within α-motor neurons of SOD1G93A mice. Following PNN breakdown, α-motor neurons of onset and mid-stage SOD1G93A mice showed increased expression of 3-nitrotyrosine, a marker for protein oxidation, which could render them vulnerable to death. Our observations suggest that increased numbers of MMP-9 expressing glia and their subsequent engulfment of PNNs around α-motor neurons render these neurons sensitive to oxidative damage and eventual death in the SOD1G93A ALS model mouse.

A solution for fillet quality: Slaughter age's effect on protein mechanism and oxidation

Physico-chemical properties of fish flesh are reliable predictors of fillet quality and nutritional value. In our study, the age-related variations of the chemical composition, pH, water activity (aw), water holding capacity (WHC), color and texture analysis, protein thermal stability, myofibrillar fragmentation index (MFI), glycogen content, protein oxidation and protein profiles were investigated in Oncorhynchus mykiss (rainbow trout) fillet. The results revealed that protein denaturation temperatures (Tmax1 and Tmax2) decreased by 2 % and 11.6 % depending on fish age. Tmax1 and Tmax2 values in the same groups were raised 71 % at 11 months' fish and this increase was 58 % at 23 months’ fish. An age-related reduction by 66.6 % and 31.25 % was noticed for protein oxidation markers sulfhydryl groups and disulfide bonds. MFI value increased by 86.6 % connected with age.The characteristics of fish meat quality are complex and are influenced by various factors that affect the degree of freshness of the product and its acceptance in the market. Taking into account the different demands of the consumer, this study has shown that age at slaughter has an impact on final product quality and that the recommended age at slaughter, taking into account market weight, positively affects meat quality.

Droplet size dependency and spatial heterogeneity of lipid oxidation in whey protein isolate-stabilized emulsions

Spatiotemporal assessment of lipid and protein oxidation is key for understanding quality deterioration in emulsified food products containing polyunsaturated fatty acids. In this work, we first mechanistically validated the use of the lipid oxidation-sensitive fluorophore BODIPY 665/676 as a semi-quantitative marker for local peroxyl radical formation. Next, we assessed the impact of microfluidic and colloid mill emulsification (respectively producing mono- and polydisperse droplets) on local protein and lipid oxidation kinetics in whey protein isolate (WPI)-stabilized emulsions. We further used BODIPY 581/591 C11 and CAMPO-AFDye 647 as colocalisation markers for lipid and protein oxidation. The polydisperse emulsions showed an inverse relation between droplet size and lipid oxidation rate. Further, we observed less protein and lipid oxidation occurring in similar sized droplets in monodisperse emulsions. This observation was linked to more heterogeneous protein packing at the droplet surface during colloid mill emulsification, resulting in larger inter-droplet heterogeneity in both protein and lipid oxidation. Our findings indicate the critical roles of emulsification methods and droplet sizes in understanding and managing lipid oxidation.

Blood Plasma as a Sampling Model during Drug-induced Thrombocytopenia: Effects of Antioxidants

OBJECTIVE Blood plasma, a complex biological mixture, plays a part in a variety of roles including clotting, defense, and transport, and reflects the overall status of blood components. Drug-induced thrombocytopenia (DIT) is characterized by abnormally low platelet count (below ~150,000 per μL) which can be caused by adverse effects of medications. This study aims to address a basic question, can plasma be employed as a sampling model to assess the oxidative stress (OS) changes and antioxidant status during DIT? The objective was to analyze the antioxidant status and OS in plasma during DIT, and to determine the effects of antioxidant supplementation such as Caripill™, L-Carnitine (LC), and vanillic acid (VA) during DIT. METHODS Male Wistar rats were used as animal models and grouped into control groups (n=5) and thrombocytopenia groups (n=5). Antioxidants were given to the thrombocytopenic and the control rats (50 mg/kg body weight) once a day for 7 days. Blood plasma from both groups was evaluated for total antioxidant capacity, antioxidant enzymes, markers of lipid peroxidation, protein oxidation, and OS. RESULTS The antioxidants significantly increased the total antioxidant capacity (CUPRAC) and ferric-reducing antioxidant power (FRAP) of the plasma and decreased the levels of conjugate dienes. Caripill™ also reduced lipid peroxidation, significantly elevated protein sulfhydryl and nitrite/nitrate levels, LC elevated lactate dehydrogenase levels, and VA increased superoxide dismutase activity and attenuated lipid peroxidation during DIT. CONCLUSIONS The antioxidants Caripill™, vanillic acid, and L-carnitine were demonstrated to be beneficial during DIT and to have prospects in alternate therapeutics. This study confirms that plasma can be utilized as a sampling model to study changes during OS situations.

Cuban policosanol: a natural compound for ischemic stroke treatment

Stroke is among the leading causes of mortality and disability; therefore, it constitutes a relevant health problem. Cuban policosanol presents lipid-lowering, antiplatelet, antioxidant and vascular endothelium protective properties, all of which give it a comprehensive anti-atherosclerotic effect. This review is aimed to show, analyze and discuss the main preclinical and clinical evidence of the effects of Cuban policosanol on ischemic stroke. Preclinical studies evidenced the anti-ischemic effects of preventive and therapeutic oral treatment with Cuban policosanol in Mongolian gerbils with cerebral ischemia induced by unilateral and permanent ligation of a carotid artery, and in global cerebral ischemia induced by bilateral clamping and recirculation of both carotids; being similar or superior to other anti-ischemic agents. Also, combination therapy with aspirin produced greater anti-stroke efficacy compared with aspirin monotherapy, but being similar to policosanol plus atorvastatin combination. This anti-stroke effect was associated to a serum thromboxane A2 (TxA2) concentrations reduction and prostacyclin (PgI2) increase, leading to a favorable TxA2/PgI2 balance, and also to the malondialdehyde (MDA) and sulfhydryl groups (SHG, lipid peroxidation and protein oxidation markers, respectively) reduction. Cuban policosanol combined with aspirin (standard therapy) improved and benefited patients with prior ischemic stroke in terms of functional and neurological outcomes, in open-label studies and in randomized, double-blind, controlled studies. These beneficial effects on stroke patients were associated with antioxidant and antiplatelet effects of policosanol. Also, the combinations of Cuban policosanol plus aspirin and atorvastatin plus aspirin compared in a clinical study significantly and similarly improved the neurological recovery of patients with ischemic stroke. Cuban policosanol was safe and well tolerated, with no serious adverse events occurring during the trials. In conclusion, Cuban policosanol is a safe and effective natural drug for ischemic stroke treatment, which is supported by preclinical and clinical evidences.

Antioxidant and Anti-Inflammatory Potential of Brassica oleracea Accelerates Third-Degree Burn Healing in Rats

Burns account for more than 265,000 deaths per year in the world, mainly associated with infections. Therefore, the shorter the healing time, the better the prognosis. Based on this, the objective of the present study was to investigate the effect of an ointment based on Brassica oleracea var. capitata extract in the third-degree healing process. Twenty-five male Wistar rats (335 ± 16 g, three months of life) were individualized in cages with food and water ad libitum. After anesthesia, two circular third-degree burn wounds (12 mm in diameter) were made on the animals, which were randomly separated into five treatments (n = 5/group), i.e., SAL: saline solution 0.9%; OV: ointment vehicle; SS: silver sulfadiazine 1%; PB1: 10% B. oleracea extract; and PB2: 20% B. oleracea extract. The animals were treated with the ointment daily for eight days. Every four days, the area and the wound contraction index were evaluated. Tissue samples were taken for histopathological analysis (cellularity, blood vessels, and extracellular matrix components) and analysis of oxidative/nitrosative status (antioxidant enzymes, lipid, and protein oxidation markers, as well as nitric oxide (NO) and hydrogen peroxide (H2O2)). The ointment based on B. oleracea var. capitata at 10 and 20% concentrations increased the number of cells, blood vessels, and fibrous components of the extracellular matrix and the activity of antioxidant enzymes, promoting a fast and efficient cutaneous repair in third-degree burn wounds.

Assessing the Impact of Pomegranate Peel Extract Active Packaging and High Hydrostatic Pressure Processing on Color and Oxidative Stability in Sliced Nitrate/Nitrite-Reduced Iberian Dry-Cured Loins

Our study aimed to assess the impact of active packaging with pomegranate peel extract (0.06 mg gallic acid eq./cm2) and/or high-pressure treatment (600 MPa, 7 min) on the instrumental color, lipid, and protein oxidation of Iberian dry loins formulated with reduced nitrate/nitrite levels (0, 37.5, and 150 mg/kg) during 100-day refrigerated storage (4 °C). CIE L*a*b* coordinates were measured, and malondialdehyde, carbonyls, and free thiol contents served as markers for lipid and protein oxidation. Active packaging lowered CIE L* (35.4 vs. 34.1) and a* (15.5 vs. 14.5) and increased yellowness (15.6 vs. 16.3) and hue (45.2 vs. 48.4), while pressurization increased CIE L* (33.1 vs. 36.3) and diminished a* values (16.1 vs. 13.9). Ongoing nitrate/nitrite amounts significantly influenced lipid peroxidation, protein carbonyl formation, and free thiol loss. Active packaging and high-pressure processing had varying effects on carbonyl and thiol contents. Neither pressurization nor active packaging impacted malondialdehyde formation. Pressurization enhanced the formation of 4-HNE (503 vs. 697 pg/g). Protein oxidation proved more sensitive to changes, with active packaging offering protection against protein carbonylation (15.4 vs. 14.7 nmol carbonyls/mg protein), while pressurization induced thiol loss (34.3 vs. 28.0 nmol Cys eq./mg protein). This comprehensive understanding provides essential insights for the meat industry, emphasizing the necessity for customized processing conditions to enhance color stability, lipid preservation, and protein integrity in dry-cured loin slices.

Dual effects of dietary carnosine during in vitro digestion of a Western meal model with added ascorbic acid.

The beneficial role of carnosine during in vitro digestion of meat was previously demonstrated, and it was hypothesized that such benefits could also be obtained in a meal system. The current study, therefore, assessed carnosine effects on markers of lipid and protein oxidation and of advanced glycation end products (AGEs) during gastric and duodenal in vitro digestion of a burger meal model. The model included intrinsic (low) and enhanced (medium and high) carnosine levels in a mix of pork mince and bread, with or without ascorbic acid (AA) and/or fructose as anti- and prooxidants, respectively. In the presence of either AA or fructose, a carnosine prooxidative potential during digestion was observed at the medium carnosine level depending on markers and digestive phases. However, free carnosine found at the high carnosine level exerted a protective effect reducing the formation of 4-hydroxynonenal in the gastric phase and glyoxal in both the gastric and duodenal phases. Dual effects of carnosine are likely concentration related, whereby at the medium level, free radical production increases through carnosine's ferric-reducing capacity, but there is insufficient quantity to reduce the resulting oxidation, while at the higher carnosine level some decreases in oxidation are observed. In order to obtain carnosine benefits during meal digestion, these findings demonstrate that consideration must be given to the amount and nature of other anti- and prooxidants present and any potential interactions. PRACTICAL APPLICATION: Carnosine, a natural compound in meat, is a multifunctional and beneficial molecule for health. However, both pro- and antioxidative effects of carnosine were observed during digestion of a model burger meal when ascorbic acid was included at a supplemental level. Therefore, to obtain benefits of dietary carnosine during digestion of a meal, consideration needs to be given to the amount and nature of all anti- and prooxidants present and any potential interactions.

Melatonin protects Kir2.1 function in an oxidative stress-related model of aging neuroglia.

Melatonin is a pleiotropic biofactor and an effective antioxidant and free radical scavenger and, as such, can be protective in oxidative stress-related brain conditions including epilepsy and aging. To test the potential protective effect of melatonin on brain homeostasis and identify the corresponding molecular targets, we established a new model of oxidative stress-related aging neuroglia represented by U-87 MG cells exposed to D-galactose (D-Gal). This model was characterized by a substantial elevation of markers of oxidative stress, lipid peroxidation, and protein oxidation. The function of the inward rectifying K+ channel Kir2.1, which was identified as the main Kir channel endogenously expressed in these cells, was dramatically impaired. Kir2.1 was unlikely a direct target of oxidative stress, but the loss of function resulted from a reduction of protein abundance, with no alterations in transcript levels and trafficking to the cell surface. Importantly, melatonin reverted these changes. All findings, including the melatonin antioxidant effect, were reproduced in heterologous expression systems. We conclude that the glial Kir2.1 can be a target of oxidative stress and further suggest that inhibition of its function might alter the extracellular K+ buffering in the brain, therefore contributing to neuronal hyperexcitability and epileptogenesis during aging. Melatonin can play a protective role in this context.

Potential neurotoxicity of αlfa-amino adipic acid, a marker of protein oxidation in ultra-processed foods, and analogue of neurotransmitter glutamic acid

Potential neurotoxicity of αlfa-amino adipic acid, a marker of protein oxidation in ultra-processed foods, and analogue of neurotransmitter glutamic acid

446 The Effects of Maternal Diet During Gestation on Oxidative Status of Offspring

Abstract Poor maternal nutrition during gestation is common in livestock production and includes both nutrient restriction and over-nutrition. Poor maternal nutrition affects offspring pre- and post-natal growth including decreases in muscularity and increases in adiposity which results in poor quantity and quality of animal products. Oxidative stress, when free radicals exceed the capacity of antioxidants, damages lipid membranes, proteins, and DNA. Oxidative stress 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 offspring circulating oxidative status in sheep. We hypothesized that offspring of restricted- and over-fed ewes would have an altered oxidative status in circulation. To test this hypothesis, multiparous Dorset ewes (n = 45) pregnant with twins were fed 100% (CON), 60% (RES), or 140% (OVER) of National Research Council requirements from d 30 of gestation until parturition. At parturition, ewes were fed a control diet such that the nutritional insult only occurred during gestation. Blood samples were collected from offspring by jugular venipuncture at d 112 and d 224 of age to evaluate oxidative status in circulation. Data were analyzed in SAS 9.4 using PROC MIXED with fixed effects of offspring sex and maternal diet with sampling timepoint as repeated measure. Data were considered significant at P < 0.05. In offspring plasma, superoxide dismutase, an endogenous antioxidant, activity was 17% greater in CON offspring compared with RES and OVER (P ≤ 0.04). Malondialdehyde (MDA), a marker of lipid peroxidation, concentration was not different at d 112 but RES animals had 10% lesser concentration of MDA than CON at d 224 (P ≤ 0.02). Protein carbonyl (PC), a marker of protein oxidation, concentration was 9% greater in CON animals than RES and OVER (P = 0.01). Additionally, PC concentrations were 19% greater at d 224 compared with d 112 (P ≤ 0.001). These results indicate that at the chosen timepoints, RES and OVER offspring had less antioxidant activity but also less indication of oxidative damage. Overall, the alterations in antioxidant activity and oxidative damage suggest dysregulation in circulating oxidative status that may contribute to the negative consequences of poor maternal nutrition during gestation. Future work should focus on the impacts of poor maternal nutrition on oxidative stress in muscle.

Protein carbonylation and structural changes in porcine myofibrillar protein exposed to metal ion-H2O2-ascorbate and linoleic acid-lipoxidase oxidizing systems

The present study aimed to compare two oxidizing systems commonly present in meat for their influence on protein oxidation patterns, with emphasis on the specific lysine-derived markers for protein carbonylation (α-aminoadipic semialdehyde, AAS; lysinonorlucine, LNL) and their relationships with the common markers for protein oxidation. For this purpose, pork myofibrillar proteins (MFP, 5 mg/mL) were suspended in 0.6 M NaCl (pH 7.5) and incubated at 4 ℃ for 24 h with two oxidizing systems: (1) a metal-catalyzed oxidizing system (MOS: 10 µM FeCl3, 100 µM ascorbic acid, and 0–10 mmol/L H2O2), (2) a linoleic acid – lipoxidase oxidizing system (LOS: 7500 units of lipoxidase/mL, and 0–10 mM linoleic acid). Results showed that the amounts of AAS and LNL in both MOS- and LOS-oxidized MFP was proportional to the oxidant concentrations (H2O2 or linoleic acid), while the formation of total carbonyl and total thiol also exhibited similar oxidant-dose-dependent patterns. Meanwhile, the α-helix contents of MFP declined with oxidant concentrations irrespective of the oxidizing systems. The reducing SDS-PAGE revealed that the myosin heavy chain band started to diminish at high H2O2 concentration (5 and 10 mM) in MOS whereas at low level of linoleic acid (0.5 mM) in LOS. Overall, these results demonstrated both oxidizing systems could be involved in the formation of AAS and LNL, and that the generation of AAS and LNL can be used as reliable markers for protein oxidation, but also might be directly involved in protein structural changes and then contribute to the alternations of protein functionality.

The incorporation of a pomegranate peel extract in the formulation of uncured dry sausages protects lipids and proteins from oxidation during in vitro gastrointestinal digestion

The effect of nitrite (0 and 150 mg/kg NaNO2) and a pomegranate peel extract (PPE) (0, 1, and 2 mL/100 g) in the formulation of dry sausages on lipid -conjugated dienes (CDEs), lipid hydroperoxides (LOOHs), malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), saturated aldehydes (SAld), - and protein oxidation -carbonyls and free thiols- before and during simulated gastrointestinal digestion were investigated. The initial oxidation status of the sausages was greatly affected by nitrite and PPE and influenced the evolution of oxidative phenomena during simulated digestion. The removal of nitrite from the sausage formulation had a negative impact on the oxidative stability of both dry sausages and digests, leading to increased levels (P < .05) of CDEs, LOOHs, MDA, 4-HNE, and SAld. Additionally, the elimination of nitrite also resulted in an increase (P < .05) in the carbonyl content in both the sausages and their digests. The PPE added to sausages counteracted the deleterious effect of nitrite removal and reduced (P < .05) lipid and protein oxidation markers in dry sausages and digests. The protective effect of PPE against oxidation was dose-dependent. Pomegranate peel extract may represent a successful strategy to prevent or slow down lipid oxidation and protein oxidation in dry sausages before and during in vitro digestion.

ВЫРАЖЕННОСТЬ ОКСИДАТИВНОГО СТРЕССА У БОЛЬНЫХ С ИНФАРКТОМ МИОКАРДА НА ФОНЕ ХОБЛ

Introduction. Oxidative stress is a pathogenetic link in the development of many diseases, including pathology of the respiratory system and cardiovascular events. Comorbidity is a topical problem of modern medicine. One of the frequent combinations is myocardial infarction against the background of chronic obstructive pulmonary disease. The peculiarities of changes in protein and lipid peroxidation, as well as the state of antioxidant protection in comorbid patients are of interest. Aim. To study protein and lipid peroxidation processes in patients with myocardial infarction against the background of chronic obstructive pulmonary disease. Material and Methods: 195 patients with myocardial infarction against the background of chronic obstructive pulmonary disease were examined. Comparison groups were represented by 130 patients with myocardial infarction without chronic obstructive pulmonary disease and 104 patients with chronic obstructive pulmonary disease. The control group included 110 somatically healthy individuals. The level of malondialdehyde was assessed as a marker of lipid peroxidation, the level of deep protein oxidation products was assessed as a marker of free radical oxidation of proteins. Antioxidant protection was assessed using plasma level of total superoxide dismutase. To evaluate non-enzymatic components of antioxidant protection, total serum antioxidant status was determined by spectroscopy. The data were statistically processed using the SPSS 26.0 software package. Results and discussion. In patients with chronic obstructive pulmonary disease the levels of protein and lipid oxidation markers were higher than in myocardial infarction. The highest levels were noted in comorbid patients. Antioxidant levels were decreased in all groups compared to controls. Patients with monosomatic myocardial infarction had lower levels of antioxidants compared with patients with chronic obstructive pulmonary disease. The lowest values were observed in the group of comorbid patients. Conclusion. Chronic obstructive pulmonary disease is accompanied by a more pronounced activation of lipid and protein peroxidation processes, but accompanied by activation of adaptive mechanisms, which is not observed in acute coronary pathology. The greatest severity of oxidative stress is characteristic of comorbid patients.