Evaluating oxidative stress biomarkers in oncology nurses exposed to antineoplastic drugs: A cross-sectional study.

PURPOSE: Antineoplastic drugs (ADs) are widely used in cancer treatment. Nurses in chemotherapy centers are exposed to these drugs during preparation. They can affect healthy cells, leading to teratogenic and mutagenic effects, as well as oxidative stress. This study aimed to evaluate oxidative stress biomarkers in the nurses exposed to these drugs. METHOD: This study was conducted on 30 nurses exposed to ADs and 30 nurses with no exposure to these drugs as non-exposed group. Oxidative stress biomarkers were measured in the blood serum samples of both groups, including malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and blood thiol groups. RESULTS: Considering the possibility of confounding effect of nutritional supplement consumption, the effect of this factor was adjusted in the analysis. A significant difference was observed for CAT, SOD, thiol, and TAC biomarkers between two groups (P < 0.05). However, the difference in MDA and GPx biomarkers between two groups was not statistically significant. CONCLUSIONS: The findings of the present study showed that supplement consumption has a significant effect on the biomarker of total antioxidant capacity. Thus, total antioxidant capacity measurement is advised as the best biomarker for tracking oxidative status in nurses exposed to ADs due to its capacity to measure all antioxidants in the body, except the thiol group, and its lower cost when compared to other biomarkers. Furthermore, it can be claimed that the consumption of nutritional supplements has a greater effect on the non-enzymatic biomarkers of oxidative stress than on enzymatic antioxidant system.

Pirfenidone alleviates vascular intima injury caused by hyperhomocysteinemia.

OBJECTIVES: Hyperhomocysteinemia (HHcy) can induce vascular inflammatory and oxidative damage and accelerate intimal hyperplasia. This study investigated the protective effect of pirfenidone (PFD) on the recovery process of injured endothelial arteries during HHcy. MATERIALS AND METHODS: Thirty rabbits were randomly separated into three groups: A control group (n=10, standard rabbit chow), a model group (n=10, control diet plus 30 g methionine/kg food), and a PFD group (n=10, model diet plus oral administration of 90 mg/day of PFD). After 14 weeks of arterial injury, histopathological changes were determined. Plasma homocysteine (Hcy) concentrations, lipid profiles and oxidant and antioxidant status were evaluated. Macrophage infiltration was assessed using immunohistochemical staining. RESULTS: PFD supplementation decreased macrophage infiltration of iliac artery significantly without changes in blood lipids and Hcy concentrations. Compared with the model group, PFD restored superoxide dismutase and glutathione peroxidase activities and reduced malondialdehyde and reactive oxygen species levels. A high-methionine diet significantly increased neointimal area and the ratio between neointimal and media area. Systemic administration of PFD inhibited neointimal formation. CONCLUSIONS: PFD can partly alleviate intimal hyperplasia by inhibiting inflammatory and oxidative stress response induced by HHcy during endothelial injury. It may be a potential therapeutic agent for the prevention and treatment of endothelial injury-associated diseases such as atherosclerosis.

Ulexite modulates the neurotoxicological outcomes of acetylferrocene-exposed rainbow trout.

In this study, the neuroprotective action potential by ulexite (UX) (18.75 mg/L) against acetylferrocene (AFC) (3.82 mg/L) induced neurotoxicity was aimed to investigate in brain tissues of Oncorhynchus mykiss. For this purpose, the effects on neurotoxicity markers, proinflammatory cytokines, antioxidant immune system, DNA, and apoptosis mechanisms were assessed on brain tissues in the 48-96  h of the 96- trial period. In this research, it was determined that brain-derived nerve cell growth factor (BDNF) level and acetylcholinesterase (AChE) activity were inhibited in the brain tissue compared to the control group by AFC. In addition, inhibition in glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and glutathione (GSH) values (which are antioxidant system biomarkers), and inductions in malondialdehyde (MDA) and myeloperoxidase (MPO) amounts (which are indicators of lipid peroxidation) were determined (p < 0.05) after exposure to AFC. And, while tumor necrosis factor-α (TNF-α) and IL-6 levels were increased in the AFC-exposed group, Nrf-2 levels were found to be remarkably decreased. Upregulation was also detected in 8-hydroxydeoxyguanosine (8-OHdG) and caspase-3 levels, which are related to DNA damage and apoptosis mechanism. On the contrary, UX (single/with AFC) suppressed the AChE and BDNF inhibition by AFC. Moreover, UX mitigated AFC-induced oxidative, inflammatory, and DNA damage and attenuated AFC-mediated neurotoxicity via activating Nrf2 signaling in fish. Collectively, our findings revealed that UX supplementation might exert beneficial effects and may be considered as a natural and promising neuroprotective agent against AFC-induced toxicity.

Naringenin Prevents Inflammation, Apoptosis, and DNA Damage in Potassium Oxonate-Induced Hyperuricemia in Rat Liver Tissue: Roles of Cytochrome C, NF-κB, Caspase-3, and 8-Hydroxydeoxyguanosine.

Background: Hyperuricemia (HU) is a metabolic disease characterized by high uric acid levels in the blood. HU is a risk factor for diabetes, cardiovascular complications, metabolic syndrome, and chronic kidney disease. Purpose: The present study was performed to determine the effect of experimental HU on xanthine oxidase (XO), tumor necrosis factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), interleukin-17 (IL-17), cytochrome C, glutathione peroxidase (GPx), caspase-3, and 8-hydroxydeoxyguanosine (8-OHdG) levels in liver tissues of rats. Study Design: Thirty-five, male, Wistar albino-type rats were used for this study. Experimental groups were formed as follows: Group 1: control group; Group 2: potassium oxonate (PO) group; group 3: PO+NAR (naringenin; 2 weeks) group; and Group 4: PO (2 weeks)+NAR (2 weeks) group (total of 4 weeks). Methods: The first group was not given anything other than normal rat food and drinking water. In the second group, a 250 mg/kg intraperitoneal dose of PO was administered for 2 weeks. In the third group, 250 mg/kg intraperitoneal PO (application for 2 weeks) and 100 mg/kg NAR intraperitoneally 1 hr after each application were administered. In the fourth group, intraperitoneal PO administration was applied for 2 weeks, followed by intraperitoneal administration of NAR for 2 weeks (4 weeks in total). At the end of the experimental period, XO, TNF-α, NF-κB, IL-17, cytochrome C, GPx, caspase-3, and 8-OHdG levels were determined in liver tissues. Results: HU increased XO, TNF-α, NF-κB, IL-17, cytochrome C, caspase-3, and 8-OHdG levels in liver tissues. However, both 2 and 4 weeks of NAR supplementation decreased these values, and also NAR supplementation led to an increase in GPx levels in tissues. Conclusions: The results of the study show that increased inflammation, apoptosis, and DNA damage in experimental HU can be prevented by administration of NAR due to inhibition of cytochrome C, NF-κB, caspase-3, and 8-OHdG.

Tart Cherry Supplement Enhances Skeletal Muscle Glutathione Peroxidase Expression and Functional Recovery after Muscle Damage.

INTRODUCTION: Montmorency cherry concentrate (MCC) supplementation enhances functional recovery from exercise, potentially due to antioxidant and anti-inflammatory effects. However, to date, supporting empirical evidence for these mechanistic hypotheses is reliant on indirect blood biomarkers. This study is the first to investigate functional recovery from exercise alongside molecular changes within the exercised muscle after MCC supplementation. METHODS: Ten participants completed two maximal unilateral eccentric knee extension trials after MCC or placebo (PLA) supplementation for 7 d before and 48 h after exercise. Knee extension maximum voluntary contractions, maximal isokinetic contractions, single leg jumps, and soreness measures were assessed before, immediately, 24 h, and 48 h after exercise. Venous blood and vastus lateralis muscle samples were collected at each time point. Plasma concentrations of interleukin-6, tumor necrosis factor alpha, C-reactive protein, creatine kinase, and phenolic acids were quantified. Intramuscular mRNA expressions of superoxide dismutase 1 (SOD1), SOD3, glutathione peroxidase 1 (GPX1), GPX3, GPX4, GPX7, catalase, and nuclear factor erythroid 2-related factor 2 and relative intramuscular protein expressions of SOD1, catalase, and GPX3 were quantified. RESULTS: MCC supplementation enhanced the recovery of normalized maximum voluntary contraction 1-s average compared with PLA (postexercise PLA, 59.5% ± 18.0%, vs MCC, 76.5% ± 13.9%; 24 h PLA, 69.8% ± 15.9%, vs MCC, 80.5% ± 15.3%; supplementation effect P = 0.024). MCC supplementation increased plasma hydroxybenzoic, hippuric, and vanillic acid concentrations (supplementation effect P = 0.028, P = 0.002, P = 0.003); SOD3, GPX3, GPX4, GPX7 (supplement effect P < 0.05), and GPX1 (interaction effect P = 0.017) gene expression; and GPX3 protein expression (supplementation effect P = 0.004) versus PLA. There were no significant differences between conditions for other outcome measures. CONCLUSIONS: MCC supplementation conserved isometric muscle strength and upregulated antioxidant gene and protein expression in parallel with increased phenolic acid concentrations.

Oral administration of potato peel extract affects serum blood metabolites, liver function and ameliorating oxidative stress induced in rabbits exposed to cold stress.

This study investigated the effect of potato peel extract (PPE), orally administrated to rabbits, on serum blood metabolites and ameliorating oxidative stress induced by cold stress under Egyptian winter conditions. Twenty-four bucks grouped into three treatments (8 animals per group) were used for the experiment. The animals received 1.5 ml of water orally, containing 0 (PPE0), 25 (PPE25) or 50 (PPE50) mg PPE/kg live weight. Bucks were randomly assigned into three homogenous equal groups according to the level of PPE. Treatments were applied to each animal every two days over a period of three months including one month as an adaptation period. At the 8th week of the experiment, blood samples were collected from each buck and at the end of the experiment, bucks were slaughtered, and some organs were collected and weighed. The PPE improved (p < 0.05) blood total protein, albumin, globulin and glucose. The blood concentration of total lipid, cholesterol, triglyceride, low density lipoprotein and very low-density lipoprotein (were increased (p < 0.02) in PPE rabbits. Furthermore, PPE extract doses decreased (p < 0.001) oxidant thiobarbituric reactive substance (TBARS) in both blood and liver. Other liver and blood antioxidant system enzymes such as catalase, glutathione peroxidase, and superoxide dismutase were improved (p < 0.005) by PPE supplementation. Overall, oral administration of PPE up to 50 mg/kg live weight can have positive effects on rabbit health under cold stress.

Ebselen and Analogues: Pharmacological Properties and Synthetic Strategies for Their Preparation.

Ebselen is the leader of selenorganic compounds, and starting from its identification as mimetic of the key antioxidant enzyme glutathione peroxidase, several papers have appeared in literature claiming its biological activities. It was the subject of several clinical trials and it is currently in clinical evaluation for the treatment of COVID-19 patients. Given our interest in the synthesis and pharmacological evaluation of selenorganic derivatives with this review, we aimed to collect all the papers focused on the biological evaluation of ebselen and its close analogues, covering the timeline between 2016 and most of 2021. Our analysis evidences that, even if it lacks specificity when tested in vitro, being able to bind to every reactive cysteine, it proved to be always well tolerated in vivo, exerting no sign of toxicity whatever the administered doses. Besides, looking at the literature, we realized that no review article dealing with the synthetic approaches for the construction of the benzo[d][1,2]-selenazol-3(2H)-one scaffold is available; thus, a section of the present review article is completely devoted to this specific topic.

Modulation of Negative Effects of Physiological Stress on Frozen-Thawed Semen with Nutrition of Organic Selenium in Ross 308 Rooster.

Current experiment was carried out in factorial 2×2 arrangement to study the effects of stress (with or without dexamethasone administration) and addition of dietary selenium (with or without selenium supplementation in the diet) in male broiler breeder on the quality of frozen-thawed sperm under oxidative stress induced by dexamethasone. A total of 24 broiler breeder roosters with the age of 28 weeks were used based on a completely randomized design with four therapeutic approaches (factorial 2×2) and six birds in each approach. The experimental treatments were: 1) basal diet without selenium supplementation and injection of saline (CON), 2) basal diet with dexamethasone injection (4 mg/kg BW, three times every other day for one week), (DEX), 3) without dexamethasone injection and supplementation with 0.3 mg/kg selenium (Sel-Plex), and 4) dexamethasone injection and basal diet supplemented with 0.3 mg/kg of diet selenium (Sel-Plex+Dex). Sperm samples were collected from roosters. Motility, progressive motility, plasma membrane integrity, viability, malondialdehyde concentration and antioxidant parameters were evaluated in fresh and frozen-thawed semen. In spite of non-significant interaction effects, factorial analysis indicated the significant effect of every factor on different experimental parameters in fresh and frozen-thawed semen (P<0.05); The results revealed that total and progressive motility, plasma membrane integrity and viability were lower in DEX group when compared with other treatments (P<0.05). On the other hand, malondialdehyde concentration was higher in DEX group in comparison with Con, Sel-Plex and Sel-Plex+DEX groups (P<0.05). Moreover, total antioxidant capacity, level of glutathione peroxidase and superoxide dismutase were lower in DEX group as compared with other treatments (P<0.05). Our findings indicated that administration of selenium in dexamethasone-receiving roosters (Sel-Plex+DEX) improved the parameters of fresh and frozen-thawed sperm; but the best results were observed in Sel-Plex treatment. Therefore, selenium supplementation in the diet of roosters without dexamethasone injection improved total motility, progressive motility, membrane integrity, viability, malondialdehyde, total antioxidant capacity, glutathione peroxidase and superoxide dismutase pre- and post-freezing. It can be concluded, selenium in organic forms in stressed and non-stressed rooster's diet might improve all motility and antioxidant parameters in fresh and frozen-thawed sperm.

Study on antioxidant effect of recombinant glutathione peroxidase 1.

Glutathione peroxidase 1 (GPx1) is an important antioxidant selenium enzyme and has a good prospect for drug development. However, the expression of GPx1 requires a complex expression mechanism, which makes the drug development of recombinant GPx1 (rGPx1) difficult. In the previous study, we expressed highly active rhGPx1 in amber-less Escherichia coli by using a novel chimeric tRNAUTuT6. However, the antioxidant effect of rhGPx1 at the cellular and animal levels has not been verified. In this study, we established isoproterenol (ISO)-induced oxidative stress injury models to study the antioxidant effect of rhGPx1 at the cellular and animal levels. Meanwhile, in order to more accurately reflect the antioxidant effect of rGPx1 in mice, we used the same method to express recombinant mouse GPx1 (rmGPx1) as a control for rhGPx1. The results of a study showed that rhGPx1 has a good antioxidant effect at the cellular and animal levels. However, due to species differences, rhGPx1 had immunogenicity in mice and antibodies of rhGPx1 could inhibit its antioxidant activity, so the antioxidant effect of rhGPx1 was not as good as rmGPx1 in mice. Nevertheless, this study provides a reliable theoretical basis for the development of rhGPx1 as an antioxidant drug.

Combined addition of superoxide dismutase, catalase and glutathione peroxidase improves quality of cooled stored stallion semen.

During cold storage stallion spermatozoa experience undergo oxidative stress, which can impair sperm function and fertilizing capacity. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) are the main endogenous enzymatic antioxidants in stallion seminal plasma, and counteract reactive oxygen species. Semen dilution reduces the endogenous antioxidant concentrations. The aim of this study was to investigate whether addition of 15 IU/mL each of SOD, CAT, and GPX to diluted stallion semen would ameliorate a reactive oxygen-mediated decrease in semen quality during 72 h of storage at 5 °C. Ejaculates (n = 7) were divided in two aliquots and diluted in INRA 96 without (control) or with addition of antioxidants. Semen analysis was performed at the time of dilution and every 24 h during chilled storage. Antioxidant supplementation completely inhibited the storage-dependent increase in activated caspase 3 (P < 0.05). Concomitantly, the antioxidant-supplemented samples had a greater percentage of viable, motile and rapidly moving sperm than control samples after 72 h storage (P < 0.05). The DNA damage, as evaluated by TUNEL assay and SCSA, increased with storage time (P < 0.05). Antioxidant supplementation did not prevent, but did significantly reduce the increase in DNA strand breakage. The results indicate part of the intrinsic apoptotic pathway leading to effector caspase activation was inhibited, although an activation of molecules with endonuclease activity still occurred. In conclusion, adding equal concentrations of SOD, CAT and GPX to a semen extender suppressed caspase-3 activation and improved preservation of stallion sperm motility and viability during 72 h of storage at 5 °C.

Extender Supplementation with Antioxidants Selected after the Evaluation of Sperm Susceptibility to Oxidative Challenges in Goats.

This study aimed to detect the most deleterious ROS for goat sperm and then supplemented the extender with a proper antioxidant. For this, 12 adult goats (aged 1-7) were used. Fresh samples were submitted to challenge with different ROS (superoxide anion, hydrogen peroxide, and hydroxyl radical) and malondialdehyde (MDA-toxic product of lipid peroxidation). After experiment 1, sperms were cryopreserved in extenders supplemented to glutathione peroxidase (Control: 0 UI/mL; GPx1: 1 UI/mL; GPx5: 5 UI/mL, and GPx10: 10 UI/mL) and catalase (Control: 0 UI/mL; CAT60: 60 UI/mL; CAT120: 120 UI/mL, and CAT240: 240 UI/mL). Each sample was evaluated by motility, plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, assay of the sperm chromatin structure, mitochondrial activity (3,3-diaminobenzidine), and measurement of lipid peroxidation (thiobarbituric acid reactive substances [TBARS]). It was possible to observe a mitochondrial dysfunction (DAB-Class IV) and low membrane integrity after hydrogen peroxide action. However, the high rates of TBARS were observed on hydroxyl radical. CAT240 presents the lower percentage of plasma membrane integrity. It was possible to attest that hydrogen peroxide and hydroxyl radical are the more harmful for goat sperm. Antioxidant therapy must be improving perhaps using combination between antioxidants.

The addition of docosahexaenoic acid (DHA) and antioxidants (glutathione peroxidase and superoxide dismutase) in extenders to epididymal sperm cryopreservation in bulls.

SummaryThe cryopreservation of epididymal sperm is an important technique that allows genetic material to be preserved, even post mortem. However, cryopreservation leads to increased oxidative stress and impaired sperm viability. Polyunsaturated fatty acid (PUFA) supplementation may improve certain sperm characteristics, but it also makes sperm more susceptible to oxidative stress, therefore adding antioxidants that counteract oxidative stress has become an option. In this context, this study aimed to evaluate the effect of the interaction between docosahexaenoic acid (DHA) and antioxidants on the quality after the cryopreservation of epididymal bull sperm. Twenty epididymides were collected after slaughter, and epididymal sperm was cryopreserved with bovine extender supplemented with docosahexaenoic acid (DHA), glutathione peroxidase (GPx) and superoxide dismutase (SOD). We verified an improvement in motility in the group that was treated only with DHA 5 µM and a concentration-dependent effect on susceptibility to lipid peroxidation that was associated with DHA concentration (1 µM, 5 µM or 10 µM). Moreover, treatment with DHA (5 µM) and SOD (20 IU/ml) resulted in higher sperm motility. Thus, the association between DHA (5 µM) and SOD (20 IU/ml) appears to be an option for increased epididymal sperm features in bulls.

[Human selenium-containing single-chain variable fragment with glutathione peroxidase activity protects NIH3T3 fibroblast against oxidative damage].

Ultraviolet B (UVB medium wave, 280-315 nm) induces cellular oxidative damage and apoptosis by producing reactive oxygen species (ROS). Glutathione peroxidase functions as an antioxidant by catalyzing the reduction of hydrogen peroxide, the more important member of reactive oxygen species. A human selenium-containing single-chain variable fragment (se-scFv-B3) with glutathione peroxidase activity of 1288 U/µmol was generated and investigated for its antioxidant effects in UVB-induced oxidative damage model. In particular, cell viability, lipid peroxidation extent, cell apoptosis, the change of mitochondrial membrane potential, caspase-3 activity and the levels of intracellular reactive oxygen species were assayed. Human se-scFv-B3 protects NIH3T3 cells against ultraviolet B-induced oxidative damage and subsequent apoptosis by prevention of lipid peroxidation, inhibition of the collapse of mitochondrial membrane potential as well as the suppression of the caspase-3 activity and the level of intracellular ROS. It seems that antioxidant effects of human se-scFv-B3 are mainly associated with its capability to scavenge reactive oxygen species, which is similar to that of the natural glutathione peroxidase.

Influência dos polimorfismos Pro198Leu, -602A/G e Arg5Pro na atividade da enzima glutationa peroxidase e no estado nutricional de indivíduos adultos com relação ao selênio / Influence of polymorphisms Pro198Leu, -602A/G and Arg5Pro in the glutathione peroxidase enzyme activity and at the nutritional status of adult individuals with respect to selenium

O objetivo deste estudo foi avaliar o estado nutricional relativo ao selênio em indivíduos adultos relacionando-o com polimorfismos no gene da enzima GPx e sua influência sobre a enzima e o balanço redox. Foram selecionados 343 estudantes da Universidade Federal do Piauí entre 20 e 50 anos, de ambos os sexos, selecionados de acordo com critérios de inclusão adotados, como ausência de doenças crônicas não transmissíveis (DCNT) dentre outros. Sangue venoso foi coletado para análise de Se, genotipagem dos SNP da GPx1 (Pro198Leu, -602A/G e Arg5Pro), da atividade das enzimas antioxidantes (GSH-Px e SOD) eritrocitárias, malondialdeído (MDA) e capacidade de absorção de radicais de oxigênio (ORAC) plasmáticas. A análise de Se foi realizada por meio de espectrometria de absorção atômica por geração de hidretos, a genotipagem por PCR em tempo real em Step One Plus, as enzimas em analisador bioquímico automático utilizando kits comerciais, o MDA em cromatografia líquida de alta eficiência e ORAC em um leitor de microplaca. A análise estatística foi realizada por meio do software R 3.0.2. Foram realizados testes de comparação de duas e de mais que três médias entre as variáveis genéticas e os parâmetros de avaliação do Se e do balanço redox. Análises de regressão linear e linear generalizada foram realizadas para identificar a influência das variáveis genéticas, antropométricas, do perfil lipídico e estilo de vida sobre o Se sanguíneo e as variáveis do balanço redox. Os dados foram considerados significativos com p menor que 5%. A idade média dos participantes foi de 24,4±5,0 anos sendo 57,7% do sexo feminino. Entre os participantes, 95,7% eram carreadores do alelo Leu do SNP Pro198Leu e G do -602A/G e não possuíam quantidades mínimas de Se plasmático para otimizar a atividade da GPx. A atividade da GPx foi significativamente mais baixa e de ORAC mais alta nos indivíduos com o genótipo Leu/Leu em relação ao Pro/Pro do SNP Pro198Leu. Os indivíduos com o genótipo Arg/Pro apresentaram atividade da GPx significativamente maior que aqueles com o genótipo Arg/Arg do SNP Arg5Pro. Não houve diferença significativa entre as médias de MDA e SOD e os genótipos dos três SNP. As variáveis genéticas, de avaliação antropométrica, do perfil lipídico e estilo de vida mostraram influência sobre os marcadores do balanço redox, alterando o perfil antioxidante dos participantes. Os indivíduos são deficientes em Se e aqueles com o alelo Leu do SNP Pro198Leu apresentam em seu organismo maior concentração de ORAC, provavelmente para proteção contra radicais livres. O alelo variante do SNP Arg5Pro mostrou-se benéfico para o estado nutricional relativo ao Se

The aim of this study was to evaluate the nutritional status relative to Se of adult individuals relating it to polymorphisms in the GPx enzyme gene and its influence on the enzyme and the redox balance. We selected 343 students of the Federal University of Piauí between 20 and 50 years, of both genders, selected according to inclusion criteria, such as the absence of chronic noncommunicable diseases (NCD) among others. Venous blood was collected for analysis of Se, genotyping of SNP of GPx1 (Pro198Leu, -602A / G and Arg5Pro), the activity of antioxidant enzymes (GSH-Px and SOD) erythrocyte, malondialdehyde (MDA) and absorption capacity of plasma oxygen radicals (ORAC). The analysis of Se was performed by atomic absorption spectrometry through hydride generation, genotyping by real time PCR in Step One Plus, enzymes in automatic biochemical analyzer by the use of commercial kits, MDA analysis was conducted in high-performance liquid chromatography and ORAC in a microplate reader. Statistical analysis was obtained using the software R version 3.0.2. Comparison tests were performed with two and more than three averages between the genetic variables and the evaluation parameters from Se and redox balance. Linear regression analysis and generalized linear were carried out to identify the influence of genetic variables, anthropometric, lipid profile and lifestyle on the sanguine Se and the variables of the redox balance. Data were considered significant for p less than 5%. The average age of participants was 24.4±5.0 years and 57.7% were female. Among the participants, 95.7% were allele carriers Leu of SNP Pro198Leu and G of -602A/G, and they did not have minimal amounts of Se plasma to optimize the activity of GPx. The GPx activity was significantly lower and that of ORAC was higher in subjects with the Leu/Leu genotype compared to Pro/Pro of SNP Pro198Leu. Individuals with the Arg/Pro genotype had GPx activity significantly higher than those with genotype Arg/Arg of SNP Arg5Pro. There was no significant difference between the means of MDA and SOD of the genotypes of the three SNP. The genetic variables, anthropometric measurements, lipid profile and lifestyle showed influence on markers of redox balance by changing the antioxidant profile of the participants. Individuals are deficient in Se, and those with the Leu allele of SNP Pro198Leu present in their bodies highest concentration of ORAC, probably to protect against free radicals. The variant allele of the SNP Arg5Pro proved to be beneficial to the nutritional status of the Se

[The relationship between selenium and gastrointestinal inflammatory diseases]. / A szelén és az emésztorendszer gyulladásos betegségeinek kapcsolata.

The cell-membrane toxicity of reactive oxygen and nitrogen species (RONS) plays an increasing role in the pathomechanism of gastrointestinal tract diseases. Trace elements are important parts of antioxidant protecting system, especially the selenium (Se), which, in the form of glutathione peroxidase contributes to the immunity of the gut (GALT). Due to the absorptional disorders and consequent malnutrition observed in the course of inflammatory bowel diseases (IBD) an important role is associated with nutritional therapy, including energy-, protein- and trace element-support. Human studies show, that IBD is mostly accompanied by lower serum Se concentrations, reduced antoxidant and increased proinflammatory activity. Adequate Se-replacement may reduce the severity of organ failure and infections, but not mortality. However, it is encouraging that in animal studies obvious preventive effect of Se has been found on IBD and chronic inflammation induced colon cancer .

Protective effect of Paeonia anomala extracts and constituents against tert-butylhydroperoxide-induced oxidative stress in HepG2 cells.

The fruit and root parts of Paeonia anomala L. are used for the treatment of many kinds of disorders in Mongolian traditional medicine. The protective effect of a fruit extract from P. anomala against tert-butylhydroperoxide-induced cell damage was evaluated in human hepatoma HepG2 cells and compared to that of a root extract from P. anomala on the basis of cell viability, generation of intracellular reactive oxygen species, cellular total glutathione concentration, and anti-genotoxicity. The fruit extract of P. anomala showed excellent protection against the oxidative stress when compared to the root extract, through free radical scavenging, enhancing cellular glutathione concentration, and inhibiting DNA damage. Chemical constituents in the fruit extract of P. anomala were investigated and two novel compounds, 2-hydroxy-6-methoxy-4-O-(6'-O-α-L-arabinofuranosyl-ß-D-glucopyranosyl)acetophenone (1) and 3,3'-di-O-methyl-4-O-(3''-O-galloyl-ß-D-glucopyranosyl)ellagic acid (2), along with 18 other known compounds were identified. Compound 2 showed better cytoprotection against tert-butylhydroperoxide than compound 1. Among other compounds isolated from the fruit extract, ellagic acid, methyl gallate, ethyl gallate, fischeroside B, and quercetin derivatives showed potent protective effects against tert-butylhydroperoxide-induced oxidative stress via inhibiting reactive oxygen species generation and increasing total glutathione levels in HepG2 cells.

Antioxidant combinations are no more beneficial than individual components in combating ram sperm oxidative stress during storage at 5°C.

The unfrozen storage of ram semen for 2-4 days is an important goal for the acceptance of artificial insemination in sheep breeding programmes. The objective was to investigate the benefits of antioxidant supplementation on the production of hydrogen peroxide (H(2)O(2)) by ram spermatozoa stored at 5°C over 3 days. Ejaculates from 9 rams were split between two defined diluents, INRA-96 and RSD-1, and cooled slowly to 5°C for storage. Four different additives (vitamin E phosphate 6-100 µmol/L, catalase 500 IU+superoxide dismutase 9-150 µmol/L, and glutathione peroxidase, 20 IU) were investigated both separately and in combination. The amount of H(2)O(2) generated was assessed by use of a 1-step fluorometric micro-plate assay. Sperm viability, acrosome integrity and membrane fluidity were assessed by flow cytometry. H(2)O(2) production in INRA-96- compared with RSD-1-diluted spermatozoa increased approximately 2-3-fold after 24h in storage at 5°C and then declined up to 72 h, while that in RSD-1 showed no change over 72 h; this had no effect on the sperm characteristics. Addition of antioxidants singly reduced H(2)O(2) production in INRA-96, regardless of concentration. Optimal concentrations were vitamin E phosphate 12.5 µmol/L, catalase 500 IU, superoxide dismutase 37 µmol/L, and glutathione peroxidase, 20 IU. In any combination, none was more effective than others. Viability was reduced but acrosomal integrity protected by the antioxidants in INRA-96 but not in RSD-1; membrane fluidity was not affected. Based on this study, there were no combinations more efficient at combating oxidative stress than any one alone.

Moringa oleifera prevents selenite-induced cataractogenesis in rat pups.

PURPOSE: The aim of this study was to investigate the protective effects of the flavonoid fraction of Moringa oleifera leaves (FMO) on selenite cataract in vivo. METHODS: Rat pups of Sprague-Dawley strain initially weighing 10­12 g on day 8 were used for the study and grouped as control (G I), selenite induced (G II), and FMO treated (G III). The rat pups in G II and G III received a single subcutaneous injection of sodium selenite (4 µg/g body weight) on day 10 and G III was administered with FMO (2.5 µg/g body weight) from day 8 to 15. Cataract was visualized from day 16. The development of cataract was assessed and rat lenses were analyzed for the activities of antioxidant enzymes (superoxide dismutase and catalase), generation of reactive oxygen species, reduced glutathione, protein oxidation, and lipid peroxidation. FMO was subjected to in vitro antioxidant assays (2,2-diphenyl-picrylhydrazyl and superoxide scavenging assays). RESULTS: The total phenolic content of FMO was 4.4 mg of catechin equivalent/g dried plant material. The extract showed remarkable activity on 2,2-diphenyl-picrylhydrazyl (IC50 36 µg/mL) and in superoxide radical (IC50 33.81µg/mL) scavenging assays. FMO effectively prevented the morphological changes and oxidative damage in lens. FMO maintained the activities of antioxidant enzymes and sulfhydryl content and prevented reactive oxygen species generation and lipid peroxidation. CONCLUSIONS: FMO was effective in preventing cataractogenesis in selenite model by enhancing the activities of antioxidant enzyme, reducing the intensity of lipid peroxidation, and inhibiting free radical generation.

A novel selenium and copper-containing peptide with both superoxide dismutase and glutathione peroxidase activities.

Superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) play crucial roles in balancing the production and decomposition of reactive oxygen species (ROS) in living organisms. These enzymes act cooperatively and synergistically to scavenge ROS. In order to imitate the synergism of these enzymes, we designed and synthesized a novel 32-mer peptide (32P) on the basis of the previous 15-mer peptide with GPX activity and a 17-mer peptide with SOD activity. Upon the selenation and chelation of copper, the 32-mer peptide is converted to a new Se- and Cu-containing 32-mer peptide (Se-Cu-32P) and displays both SOD and GPX activities and its kinetics was studied. Moreover, the novel peptide was demonstrated to be able to better protect vero cells from the injury induced by xanthine oxidase (XOD)/xanthine/Fe2+ damage system than its parents. Thus, this bifunctional enzyme imitated the synergism of SOD and GPX and could be a better candidate of therapeutic medicine.

Antioxidants and the Comet assay.

It is widely accepted that antioxidants, either endogenous or from the diet, play a key role in preserving health. They are able to quench radical species generated in situations of oxidative stress, either triggered by pathologies or xenobiotics, and they protect the integrity of DNA from genotoxicants. Nevertheless, there are still many compounds with unclear or unidentified prooxidant/antioxidant activities. This is of concern since there is an increase in the number of compounds synthesized or extracted from vegetables to which humans might be exposed. Despite the well-established protective effects of fruit and vegetables, the antioxidant(s) responsible have not all been clearly identified. There might also be alternative mechanisms contributing to the protective effects for which a comprehensive description is lacking. In the last two decades, the Comet assay has been extensively used for the investigation of the effects of antioxidants and many reports can be found in the literature. The Comet assay, a relatively fast, simple, and sensitive technique for the analysis of DNA damage in all cell types, has been applied for the screening of chemicals, biomonitoring and intervention studies. In the present review, several of the most well-known antioxidants are considered. These include: catalase, superoxide dismutase, glutathione peroxidase, selenium, iron chelators, melatonin, melanin, vitamins (A, B, C and E), carotenes, flavonoids, isoflavones, tea polyphenols, wine polyphenols and synthetic antioxidants. Investigations showing beneficial as well as non-beneficial properties of the antioxidants selected, either at the in vitro, ex vivo or in vivo level are discussed.