Erythrocyte Glutathione Peroxidase Activity Research Articles

Effects of Different Preparations Containing Selenium on Selenium Status and Reproductive Performance of Common Carp (Cyprinus carpio L.) Broodstock

Abstract This study evaluated the efficiency of different Selenium supplements on blood Se status and reproductive performance of carp broodstock. Female carp (n=120) were distributed in 4 groups supplemented with Se as follows: control (non-supplemented), sodium selenite 200 µg/kg feed, sodium selenite i/m injection (160 µgSe/kg bodyweight), and selenized yeast 200 µg/kg feed. Blood was sampled on days 1, 20, and 30. On day 30, samples of roe were taken from females, and samples of blood and milt from 10 unsupplemented males. Larvae samples were taken after hatching. Plasmatic Se concentration was 51.38±3.77 µg/kg (day 1) and did not vary significantly. The erythrocyte Se concentration increased from 14.04±3.05 µg/kg (day 1), reaching 90.58±12.43 (day 20), to 212.38±57.87 µg/kg (day 30). Plasmatic glutathione peroxidase activity in supplemented groups increased from 4.41±1.15 to 7.73±2.26 μkat/L and plateaued until day 30. A similar pattern was observed for erythrocyte glutathione peroxidase activity, ranging from 54.51±15.45 μkat/L (day 1) to 80.72± 6.82 μkat/L (day 30). Se concentration and selenoenzyme activities in males did not differ from the female control group. Roe Se content ranged from 48.26±17.53 μg/L in control to 65.68±34.39 μg/L in fish supplemented selenized yeast, and in the pooled larvae samples, ranged from 26-43 μg/L. The Se concentration in the milt was 24.78±4.27 μg/L. Results suggest that 250 µgSe/kg feed was sufficient to meet the requirements of mature carp, sodium selenite being more efficient in elevating blood Se concentrations and selenoenzymes activities, while selenized yeast being more efficient in roe and larvae.

Effect of oleocanthal-rich olive oil on postprandial oxidative stress markers of patients with type 2 diabetes mellitus

Background: Type 2 diabetes mellitus (T2DM) is characterized by postprandial dysmetabolism, which has been linked to post-meal redox disturbances. Oleocanthal (OO), one of the most potent bioactive phenols of extra virgin olive oil, has shown redox modulating properties in vitro. However, its acute, in vivo antioxidant properties have never been studied before. Objective: The aim of this study was to investigate the kinetics of five redox markers (Thiobarbituric acid-reactive substances [TBARS] and glutathione peroxidase activity in serum-GPx3 and erythrocytes (GPx1), protein carbonyls in serum) after the consumption different meals. Design: Five different isocaloric meals comprised of white bread and butter (BU) or butter plus ibuprofen (BU-IBU) or olive oil poor in OO or olive oils containing 250 and 500 mg/Kg of oleocanthal (OO250 and OO500, respectively). We hypothesized that OO-rich olive oil will reduce postprandial oxidative stress in T2DM patients compared to other lipid sources. This study involved 10 patients with T2DM and had a cross-over design. Results: The comparison of incremental Area Under Curves (iAUCs) has shown that OO-rich olive oils were able to alleviate the increments of thiobarbituric acid-reactive substances (TBARS) and GPx3 and induce a higher red blood cells (RBCs) GPx1 activity compared to OO (P < 0.05). The effect was dose and redox marker depended. Correlation analysis in the pooled sample demonstrated a positive association between postprandial ex vivo platelet sensitivity to ADP and iAUC TBARS. In conclusion, our study has shown that OO-rich olive oils can favorably modulate lipid peroxidation and RBC GPx activity in T2DM patients when consumed as part of a carbohydrate meal. Discussion: This study demonstrates for the first time that, apart from its anti-inflammatory and antiplatelet properties, OO can also exert acute antioxidant effects. Conclusion: This finding emphasizes the health benefits of extra virgin olive oil, particularly those with a high OO content, for T2DM patients.

Effects of parity and week after calving on the metabolic, redox, and immune status of dairy cows

At the onset of lactation in dairy cows, inflammation and oxidative stress may occur and result in a risk of pathologies and lower milk yield. To propose an innovative management strategy for cows during this period, it is essential to better understand these physiological variations. Our objective was to evaluate the metabolic, redox and immune status of 7 primiparous and 8 multiparous Holstein cows during late gestation and the first months of lactation. Blood samples were collected between 3 weeks before calving until 12 weeks postpartum. Milk samples were also collected, but only at the time points after calving. The metabolic (nonesterified fatty acids (NEFA), BHB, glucose, urea, calcium) and redox (reactive oxygen metabolites (ROM), oxidative stress index (OSI), glutathione peroxidase activity, vitamin E) statuses were analyzed in plasma or erythrocytes. The expression of genes related to antioxidant functions was determined in leukocytes collected from milk. For immune status, plasma cytokine levels and the production of reactive oxygen species (ROS) in classical and regulatory neutrophils were measured in 2 whole blood ex vivo challenges. The data were analyzed using a mixed model that included the fixed effects of parity and week and their interaction. Milk yield, plasma NEFA and BHB in wk 2 and 4 after calving were higher in multiparous cows than in primiparous cows, whereas glucose and calcium tended to be lower. Plasma ROM and OSI levels in wk 8 were higher in multiparous than in primiparous cows. Multiparous cows also displayed higher glutathione peroxidase activity in erythrocytes, and antioxidant transcription factor and superoxide dismutase-1 expression levels in milk leukocytes. Moreover, multiparous cows had higher plasma concentrations of vitamin E but lower plasma levels of cytokines CXCL10, CCL2, IL1Rα and IFNγ. Following ex vivo whole blood stimulation with Escherichia coli, lower IL1α and TNFα levels were measured in multiparous than in primiparous cows. Intracellular ROS production by neutrophils was lower in multiparous than in primiparous cows. These results thus indicated marked physiological changes in wk 8 compared with wk 2 and 4 of lactation. These differences in the physiological status of primiparous and multiparous cows offer interesting perspectives for potential dietary strategies to prevent pathologies which take account of parity and week relative to calving.

Anti-Vasculogenic, Antioxidant, and Anti-Inflammatory Activities of Sulfated Polysaccharide Derived from Codium tomentosum: Pharmacokinetic Assay.

The purpose of this paper was to investigate the anti-inflammatory and anti-angiogenic activities of sulfated polysaccharide from C. tomentosum (PCT) using carrageenan (CARR)-induced paw edema in a rat model and anti-vasculogenic activity on a chorioallantoic membrane assay (CAM) model. Based on in vitro tests of anti-radical, total antioxidant, and reducing power activities, PCT presents a real interest via its antioxidant activity and ability to scavenge radical species. The in vivo pharmacological tests suggest that PCT possesses anti-inflammatory action by reducing paw edema and leukocyte migration, maintaining the redox equilibrium, and stabilizing the cellular level of several pro-/antioxidant system markers. It could significantly decrease the malondialdehyde levels and increase superoxide dismutase, glutathione peroxidase, and glutathione activities in local paw edema and erythrocytes during the acute inflammatory reaction of CARR. PCT pretreatment was effective against DNA alterations in the blood lymphocytes of inflamed rats and reduced the hematological alteration by restoring blood parameters to normal levels. The anti-angiogenic activity results revealed that CAM neovascularization, defined as the formation of new vessel numbers and branching patterns, was decreased by PCT in a dose-dependent manner, which supported the in silico bioavailability and pharmacokinetic findings. These results indicated the therapeutic effects of polysaccharides from C. tomentosum and their possible use as anti-proliferative molecules based on their antioxidant, anti-inflammatory, and anti-angiogenic activities.

Systematic review and meta-analysis of oxidative stress and antioxidant markers in recurrent aphthous stomatitis

BackgroundWe performed this systematic review and meta-analysis to synthesize all studies that reported the level of oxidative and antioxidative markers in recurrent aphthous stomatitis (RAS) patients compared to controls.MethodsWe registered our study in PROSPERO (CRD42023431310). PubMed, ProQuest, Scopus, EMBASE, Google Scholar, and Web of Science were searched to find relevant publications up to June 5, 2023. The standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. We included 30 articles after multiple stags of screening.ResultsWe found that erythrocyte superoxide dismutase and Glutathione peroxidase activity were significantly lower in patients with RAS compared to healthy controls (SMD = − 1.00, 95%CI = -1.79 to -0.21, p = 0.013, and SMD = − 1.90, 95%CI = -3.43 to -0.38, p = 0.01, Respectively). However, there was not any difference between patients with RAS and healthy controls in erythrocyte Catalase (SMD = − 0.71, 95%CI = -1.56–0.14, p = 0.10). The total antioxidant status (TAS) level, in serum was significantly lower in patients than healthy controls (SMD = − 0.98, 95%CI = -1.57 to -0.39, p = 0.001). In addition, RAS patients had higher levels of serum Malondialdehyde (MDA), Serum total oxidant status, and serum oxidative stress index than healthy controls (SMD = 2.11, 95%CI = 1.43–2.79, p < 0.001, SMD = 1.53, 95%CI = 0.34–2.72, p = 0.01, and SMD = 1.25, 95%CI = 0.25–2.25, p = 0.014, Respectively); However, salivary MDA and TAS, and serum uric acid, vitamin E and C, and reduced glutathione levels of patients with RAS were not different from that of healthy controls.ConclusionsThe relationship between oxidative stress and RAS is well established in this meta-analysis. Although the molecular processes underlying the etiology of this pathology remain unknown, evidence indicating oxidative stress has a significant role in the pathogenesis of RAS has been revealed.

Total Antioxidant Capacity, Lipid Peroxidation, and Erythrocyte Antioxidant Enzyme Activities in Subjects with Obesity: A Case-Control Study

Introduction: Considering that the prevalence of obesity has increased dramatically in recent years, one of the key targets of public health is obesity and its associated pathological conditions. Recent evidence suggests that oxidative stress (OS) may be the mechanistic link between obesity and the development of metabolic and vascular diseases related to obesity. In this study, it was hypothesized that obesity would be associated with lipid peroxidation (LP) and antioxidant enzyme activities in erythrocytes. Methods: In this case-control study, 80 subjects with obesity and 80 age- and gender-matched subjects with normal weight were selected from the health centers affiliated with Zabol University of Medical Sciences, Iran. General information was gathered from each participant using questionnaires. Serum malondialdehyde (MDA) and total antioxidant capacity (TAC), as well as, superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) activities underwent assessment. Results: The study sample consisted of 160 obese adults (42.5% males and 57.5% females, with a mean age of 41.0±7.6 years). Serum MDA levels (P=0.016) and erythrocyte SOD activity (P=0.013) were significantly higher in subjects with obesity compared to non-obese controls. Moreover, subjects with obesity had significantly lower serum TAC (P=0.008) in comparison to the controls. There were no significant differences in erythrocyte GPX and CAT activities between subjects with obesity and non-obese controls. Significant positive correlations were observed between body mass index (BMI) and serum MDA levels (r=-0.461, P&lt;0.001) and erythrocyte SOD activity (r=-0.442, P=0.002). Furthermore, a significant inverse correlation was found between BMI and serum TAC levels (r=-0.426, P=0.008). Conclusion: The present findings provide further evidence suggesting that obesity leads to substantial LP and OS, which, in turn, may contribute to the development of obesity-related diseases.

Вплив aктовегіну на механізми розвитку окисного стресу у хворих на цукровий діабет 2-го типу з кардіоваскулярною автономною нейропатією

The effects of actovegin on the mechanisms of oxidative stress (OS) developing in the blood of patients with type 2 diabetes mellitus (DM2) and cardiovascular autonomic neuropathy (CVAN) were investigated. The aim of the study was to establish the effectiveness of treatment with actovegin for the pro- and antioxidant balance impairment and changes in gene expression of HIF-1α and mTOR in the blood of patients with DM2 and CVAN. It was shown that intravenous injections of actovegin at a dose of 1000 mg per day for 10 days and further prolonged oral administration of this drug at a dose of 800 mg per day for 90 days led to a decrease in the content of secondary products of lipid peroxidation in blood plasma and H2O2 production in erythrocytes of patients with DM2 and CVAN. These changes were indicative of a weakening of OS intensity. It was also shown that treatment with actovegin promoted an increase in total plasma SOD activity as well as reduced glutathione and glutathione peroxidase activity in erythrocytes from patients. Treatment with actovegin also raised the gene expression of HIF-1α and reduced the gene expression of mTOR in leukocytes of patients with DM2 and CVAN. These genetic changes may serve as a protective mechanism against the development of OS, which acts through different metabolic pathways. So, actovegin administration counteracting OS development due to the impact on the different components of pro- and antioxidant system as well as on HIF-1α and mTOR genes expression may offer new clinical avenues for pharmacological treatment of patients with DM2 and CVAN.

Arsenic exposure and increased C-reactive protein are independently associated with lower erythrocyte glutathione peroxidase activity in Bangladeshi children

Toxic metal contaminants present in food and water have widespread effects on health and disease. Chalcophiles, such as arsenic, cadmium, and mercury, show a high affinity to selenium and exposure to these metals could have a modulating effect on enzymes dependent on selenocysteine in their active sites. The aim of this study was to assess the influence of these metals on the activity of the selenoprotein glutathione peroxidase 1 (GPX1) in erythrocytes of 100 children residing in rural Bangladesh, where drinking water often contains arsenic. GPX1 expression, as measured using high-throughput immunoblotting, showed little correlation with GPX activity (rs = 0.02, p = 0.87) in blood samples. Toxic metals and selenium measured in erythrocytes using inductively coupled plasma mass spectrometry (ICP-MS) and C-reactive protein (CRP) measured in plasma, were all considered as effectors of this divergence in GPX enzymatic activity. Arsenic concentrations in erythrocytes were most influential for GPX1 activity (rs = −0.395, p < 0.0001), and CRP levels also negatively impacted GPX1 activity (rs = −0.443, p < 0.0001). These effects appear independent of each other as arsenic concentrations and CRP showed no correlation (rs = 0.124, p = 0.2204). Erythrocyte selenium, cadmium, and mercury did not show any correlation with GPX1 activity, nor with CRP or arsenic. Our findings suggest that childhood exposure to inorganic arsenic, as well as inflammation triggering the release of CRP, may negatively affect GPX1 activity in erythrocytes.

Association of Serum Selenium and Selenoprotein P with Oxidative Stress Biomarkers in Patients with Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age which is characterized by various reproductive and metabolic disorders. Oxidative stress (OS) is now recognized to be involved in the pathogenesis of PCOS which could be targeted in the management of PCOS-related complications. Selenium (Se), as an antioxidant trace element, has been shown to decrease in PCOS patients. This study aimed to investigate the relationship between the Se and selenoprotein P (SELENOP) levels with OS markers in women with PCOS. In this cross-sectional study, 125 females aged 18-45 years diagnosed with PCOS were included. Demographic, clinical, and lifestyle information of participants were obtained using the relevant questionnaires. Fasting blood samples were collected to measure biochemical parameters. Serum levels of thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase activities as well as anthropometric measurements were assessed across tertiles of serum concentrations of Se and SELENOP. Higher serum levels of Se were associated with higher serum TAC levels (β=0.42, P<0.001) and erythrocytes GPx activity (β=0.28, P=0.002) as well as with lower serum TBARS levels (β= -0.26, P=0.003). Similarly, higher serum levels of SELENOP were associated with higher TAC (β=0.32, P<0.001) and erythrocyte GPx activity (β=0.30, P=0.001). SELENOP also showed an inverse association with serum levels of TBARS (β= -0.40, P<0.001). Nevertheless, erythrocytes SOD and CAT activities showed no significant relationships with serum Se and SELENOP concentrations (all P>0.05). The present study found that serum Se and SELENOP levels were inversely associated with TBARS levels and positively associated with TAC levels and erythrocytes GPx activity.

Selenium Biomarkers and Their Relationship to Cardiovascular Risk Parameters in Obese Women.

A cross-sectional study was carried out with 210 women divided into a case group (obese, n = 84) and a control group (eutrophic, n = 126). Body weight, height, waist circumference (WC), and hip and neck circumference were measured and the waist-hip ratio and conicity index were calculated. Selenium in plasma, erythrocytes and urine, erythrocyte GPx activity, lipid profile, Castelli I and II indices, and systolic and diastolic blood (DBP) pressure were evaluated. Mean dietary selenium intake (µg/kg/day) and plasma and erythrocyte concentrations were lower in the obese group compared to the healthy group (p < 0.001). while urinary selenium concentrations were higher (p < 0.001). There was a statistical difference between groups regarding cardiovascular risk parameters: waist circumference, neck circumference, waist-hip ratio, conicity index, triacylglycerols (TGC), and lipoproteins rich in triacylglycerols (VLDL-c) (p > 0.05). There was a negative correlation between plasma selenium concentrations and total cholesterol (TC), non-high-density lipoprotein (non-HDL), low-density lipoprotein (LDL-c), and systolic blood pressure (SBP). Urinary selenium correlated negatively with waist circumference and hip circumference and positively with neck circumference, TC, TGC, high-density lipoprotein (HDL-c), non-HDL, and VLDL-c. There was a negative correlation between dietary selenium and waist circumference, waist-hip ratio, neck circumference, conicity index, non-HDL cholesterol, LDL-c, and Castelli indices I and II, as well as a positive correlation with HDL-c and diastolic blood pressure. Women with obesity present changes in their nutritional status related to selenium, as well as increased cardiovascular risk parameters. Thus, the positive role of selenium in protecting the risk of cardiovascular disease is likely.

Decreased Activity of Erythrocyte Catalase and Glutathione Peroxidase in Patients with Schizophrenia.

Background and Objectives: Catalase and glutathione peroxidase (GPx) are important antioxidant enzymes that break down hydrogen peroxide (H2O2) in order to control its intracellular concentration, thus enabling its physiological role and preventing toxic effects. A lack or disruption of their function leads to the accumulation of hydrogen peroxide and the occurrence of oxidative stress. Accumulating studies have shown that the activities of key antioxidant enzymes are impaired in patients with schizophrenia. Since the published results are contradictory, and our previous studies found significantly higher erythrocyte superoxide dismutase (SOD) activity in patients with schizophrenia, the aim of this study was to determine the activity of enzymes that degrade hydrogen peroxide in the same group of patients, as well as to examine their dependence on clinical symptoms, therapy, and parameters associated with this disease. Materials and Methods: Catalase and GPx activities were determined in the erythrocytes of 68 inpatients with schizophrenia and 59 age- and gender-matched healthy controls. The clinical assessment of patients was performed by using the Positive and Negative Syndrome Scale (PANSS). The catalase activity was measured by the kinetic spectrophotometric method, while the GPx activity was determined by the commercially available Ransel test. Results: Erythrocyte catalase and GPx activities were significantly lower (p < 0.001 and p < 0.01, respectively) in subjects with schizophrenia than they were in healthy individuals. Lower catalase activity does not depend on heredity, disease onset, the number of episodes, or disease duration, while GPx activity showed significant changes in patients who had more than one episode and in those who had been suffering from the disease for over a year. Significantly lower catalase activity was noted in the PANSS(+/−) group in comparison with the PANSS(+) and PANSS(−) groups. The lowest catalase activity was found in subjects who were simultaneously treated with first- and second-generation antipsychotics; this was significantly lower than it was in those who received only one class of antipsychotics. Conclusion: These results indicate the presence of oxidative stress in the first years of clinically manifested schizophrenia and its dependence on the number of psychotic episodes, illness duration, predominant symptomatology, and antipsychotic medication.

Effects of Regular Brazil Nut (Bertholletia excelsa H.B.K.) Consumption on Health: A Systematic Review of Clinical Trials.

The Brazil nut (BN) is a promising food due to its numerous health benefits, but it is still necessary to systematically review the scientific evidence on these benefits. Thus, we examined the effects of regular BN consumption on health markers in humans according to the health state (with specific diseases or not) of the subjects. PubMed, Embase®, and Scielo databases were used to search for clinical trials. The PRISMA guideline was used to report the review, and the risk of bias for all studies was assessed. Twenty-four studies were included in the present review, of which fifteen were non-randomized. BNs were consumed in the context of a habitual free-living diet in all studies. Improvement in antioxidant status through increased levels of selenium and/or glutathione peroxidase activity in plasma, serum, whole blood, and/or erythrocytes was observed in all studies that evaluated antioxidant status, regardless of the health state of the sample. In addition, healthy subjects improved lipid markers and fasting glucose. Subjects with obesity had improvement in markers of lipid metabolism. Subjects with type 2 diabetes mellitus or dyslipidemia improved oxidative stress or DNA damage. Subjects undergoing hemodialysis benefited greatly from BN consumption, as they improved lipid profile markers, oxidative stress, inflammation, and thyroid function. Older adults with mild cognitive impairment improved verbal fluency and constructional praxis, and controversial results regarding the change in a marker of lipid peroxidation were observed in subjects with coronary artery disease. In conclusion, the benefits of BN consumption were found in different pathways of action and study populations.

Haematological Parameters and Glutathione Peroxidase Activity in Rugby Players

Background: Rugby is team sport and posses both running and contact play features. In a similar way as another sport producing both physical and psychological stress and both aerobic and anaerobic metabolism, rugby induces intensive oxidative stress. This in turn decreases glutathione peroxidase activity. Furthermore, the complete blood count is severely altered by such a condition. Methods: Twelve Italian rugby players were studied. Subjects were studied in the morning of the day of the match and 10 min after the end of match. Erythrocyte glutathione peroxidase activity was analyzed in control and athlete groups pre and post the rugby match both with and without in vitro addition of vitamin C. Using a Coulter counter, we measured red blood cell count, hematocrit, hemoglobin, mean corpuscular volume, white blood cell count, platelets, neutrophils, eosinophils and basophils in 12 male athletes, who gave their informed consensus. Results: GPX data show that its activity is increased by the in vitro addition of Vitamin C (48mM final concentration), both in controls and rugby players. Haematological data describe the major alterations of particulate fraction of blood from rugby players before and after one match and confirm the structural damages in this fraction. GPX activity is worsened by this kind of strenuous exercise and ascorbic acid relieves such damage. Complete blood cell counts of athletes confirm blood cell damages. Conclusion: In summary rugby players show evident cell count derangements and water-soluble reducing Vitamin C relieves oxidative damages of samples from test subjects undergone to full match fatigue.

Effects of Calorie Restricted Diet on Oxidative/Antioxidative Status Biomarkers and Serum Fibroblast Growth Factor 21 Levels in Nonalcoholic Fatty Liver Disease Patients: A Randomized, Controlled Clinical Trial.

Oxidative stress plays a fundamental role in the development and progression of nonalcoholic fatty liver disease (NAFLD). This study aimed to investigate the effects of a calorie-restricted (CR) diet on oxidative/anti-oxidative status in patients with NAFLD and the potential mediating role of fibroblast growth factor 21 (FGF-21) in this regard. This randomized, controlled clinical trial was carried out on sixty patients with NAFLD aged 20 to 60 years with body mass index (BMI) ranging from 25 to 35 kg/m2. Participants were randomly assigned to either the CR diet group (received a prescribed low-calorie diet for twelve weeks, n = 30) or the control group (n = 30). Fasting blood samples, anthropometric measurements, dietary intake, and physical activity data were collected for all participants at baseline and at the end of the trial. Significant reductions in weight, BMI, waist circumference, and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were observed in the CR diet group compared to the control group (all p < 0.05). Liver steatosis grade, serum levels of malondialdehyde (MDA), total antioxidant capacity (TAC), and FGF-21, as well as erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities did not show significant changes in the CR group when compared to the controls at the end of the study (p > 0.05). CR diet with moderate weight loss has some favorable effects on NAFLD but was not able to modify oxidative/anti-oxidative status in these patients. Future studies are warranted to target the effects of long-term interventions with a greater weight loss in this patient population.

Effects of selenium supplementation on glycemic control markers in healthy rodents: A systematic review protocol.

BackgroundIn vivo and in vitro studies have shown that Se has an insulin-mimetic action associated with its antioxidant activity. Other studies, in turn, suggest that high Se doses and high selenoprotein expression interfere with insulin signaling. This study aims to evaluate the effects of Se supplementation on glycemic control markers in healthy rodents.MethodsThe protocol was developed according to the Preferred Reporting Items for Systematic Review and Metaanalysis Protocol (PRISMA-P) and was published in the International Prospective Register of Systematic Reviews database (PROSPERO; CRD4202121201142019119181). Experimental, randomized, or non-randomized studies of healthy rodents models will be included. All forms of supplemented Se will be considered, including organic, inorganic, and synthetic compounds, selenium-enriched yeasts, zerovalent Se nanoparticles, and selenized polysaccharides. Fasting blood glucose will be considered the primary outcome. Homeostatic model assessment, plasma and erythrocyte Se concentration, GPX activity, SELENOP concentration, and other Se biomarkers will be considered secondary outcomes. EMBASE, Scopus, Pubmed/Medline, Web of Science, and CINAHL will be searched for articles published with no language restrictions. Two reviewers will independently conduct the search and selection of articles, data extraction, and quality analysis. The risk of bias and methodological quality analyses of the included studies will be performed using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) and Collaborative Approach to Meta-Analysis and Review (CAMARADES) tools, respectively. The results will be presented as a narrative synthesis according to the Synthesis Without Meta-analysis (SWiM) Reporting Guideline. Meta-analyses will be conducted where appropriate using random-effects models.DiscussionThe review may clarify the interaction between different forms of supplemented Se and glycemic control in rodents models. The results will provide evidence that will help select doses and forms of Se to administer in clinical trials while according to impact on the glycemic control while elucidating mechanisms of Se metabolism.

Association between the physical activity and metabolic syndrome in residents of a foot-hill area in India

Background and aimsPhysical inactivity, has been linked to development of metabolic syndrome, which increases the risk of developing cardiovascular disease. Aim of the study was to assess the level of physical activity and it's association with prevalence of metabolic syndrome and oxidative stress in a semiurban foothill population of India. MethodsParticipants (n = 288), >18 years of age were enrolled. Their demographics and clinical details were recorded. Fasting plasma glucose, triglycerides, cholesterol and erythrocyte glutathione peroxidase activity were measured. Physical activity was estimated using Global Physical Activity Questionnaire and converted into metabolic equivalent in minutes per week. Results37.5% of study population was found to be physically active, with more males (43.3%) being active than females (23.3%). Inactivity was associated with higher triglycerides levels in males and with higher hip circumference, diastolic blood pressure, triglycerides and fasting plasma glucose in females. No significant difference was found in the oxidative stress, indicated by decreased glutathione peroxidase activity, between active and inactive persons or persons with normal and increased body mass index. ConclusionsThere is a high prevalence of physical inactivity in this region of India, with prevalence of physical inactivity higher is females as compared to males. No significant co-relation was found between the levels of activity and components of metabolic syndrome and oxidative stress in the study population.

Dorsal scapular displacement (flying scapula) in a heifer

AbstractDorsal scapular displacement, or flying scapula, is a rare condition characterised by sinking of the thorax between the forelimbs and protruding of the scapula above the thoracic vertebrae with the impression of a humpback appearance of the affected individual. The aetiology is still a matter of controversy. A 10‐month‐old heifer was presented with a history of sudden onset of gait abnormality and reluctance to stand and walk after being turned out to a spring pasture following the winter housing period. Clinical examinations revealed signs consistent with flying scapula. Whole‐blood selenium concentration and erythrocyte glutathione peroxidase activity were within the marginal status. Vitamin E level in serum was within the reference range. We proposed that the condition resulted from damage and bilateral rupture of the serratus ventralis muscle due to dystrophic myodegeneration in a selenium‐deficient individual exacerbated by walking long distances and unaccustomed physical activity after winter housing.

Nutritional status of selenium in overweight and obesity: A systematic review and meta-analysis

Selenium is an antioxidant and anti-inflammatory nutrient and regulates important physiological processes, such as carbohydrate and lipid metabolism, immune system actions, and adipocyte differentiation. Given these important functions, several studies have assessed the nutritional status of selenium to elucidate whether its homeostasis is impaired by excess adiposity, which in turn could contribute to the adipose tissue dysfunction and metabolic disorders. However, the results of these studies are quite controversial. Therefore, this systematic review and meta-analysis aimed to assess differences in the nutritional status of selenium in overweight/obese individuals. We searched the PubMed, Scopus, Web of Science, Embase, Cochrane Library, and Virtual Health Library databases. Studies comparing overweight or obese individuals with eutrophic individuals and assessing at least one marker of selenium were included. Comprehensive Meta-Analysis software was used to perform meta-analysis. The effect size was calculated using the raw mean difference or the standardized mean difference, with 95% confidence interval and a p-value of <0.05. Heterogeneity was determined using the I2 index. Subgroup analyses were performed according to sex, body mass index (BMI), and selenium content in the soil. The protocol of this review was registered in the Prospective Register of Systematic Reviews (registration number: CRD42020185405). This systematic review included 73 articles, of which 65 articles were eligible for meta-analysis. There were no significant differences between the overweight/obesity and eutrophy groups in terms of dietary intake and plasma/serum levels of selenium and selenoprotein P levels. The activity of plasma/serum glutathione peroxidase was decreased in the overweight/obese children and adolescents; however, the difference was no statistically significant when the enzyme activity was analyzed in erythrocytes and whole blood. In the adult age group, overweight/obese individuals had decreased activity of both glutathione peroxidase isoforms compared to those individuals with eutrophy. In particular, the activity of erythrocyte glutathione peroxidase was significantly decreased in obese individuals and those living in regions with low-to-moderate selenium content in the soil. Regarding selenium excretion markers, overweight/obese individuals had lower levels of selenium in the urine and nails and a trend of higher levels of selenium in the hair than eutrophic individuals. In conditions of excess adiposity, the main alteration in the nutritional status of selenium is a decrease in glutathione peroxidase activity, particularly in adults with obesity. In addition, reduced levels of selenium in urine and nails can be found in overweight or obese individuals.

Selenium nutritional status and its association with SLEDAI-2K, HOMA-IR and lipid profile in Juvenile Systemic Lupus Erythematosus patients.

To assess nutritional status regarding selenium in adolescents with Juvenile Systemic Lupus Erythematosus (jSLE) and analyze possible associations with disease activity, insulin resistance and lipid profile. This was an observational, cross-sectional study of 31 female adolescents with jSLE and 31 healthy female volunteers as a comparison group. We obtained demographic, anthropometric (weight, stature, waist, and neck circumferences), and clinical data (disease activity measured by SLEDAI-2K) from both groups; laboratory data including: lipid profile, plasma selenium, erythrocyte glutathione peroxidase activity (GPx), plasma malondialdehyde (MDA), ultrasensitive C-reactive protein (usCRP), insulin levels, and glycemia (Homeostasis Model Assessment for Insulin Resistance-HOMA-IR). Mean age at diagnosis of jSLE group was 15.9±1.7years, with mean disease duration of 3.6±2.6years. 48% of patients and controls had below-reference Se levels (≤46mcg/L). GPx was more frequently below reference levels (<4.171U/L) in the jSLE group, compared to controls. A ROC curve was used to assess the power of the variables to discriminate between both groups; insulin (AUC = 0.712; CI 95% 0.584-0.840), waist-to-height ratio (AUC = 0.704; CI 95% 0.572-0.837), and HOMA-IR (AUC = 0.689; CI 95% 0.556-0.822) were the variables with the greatest discriminatory power. Linear regression showed an independent inverse association between Se levels and c-LDL; no such correlation was found for GPx activity. SLEDAI-2K and HOMA-IR showed no association with levels of Se and GPx activity. Approximately, 50% of jSLE adolescents had below reference Se levels. The frequency of inadequate GPx values was higher in patients, compared to controls. There was an independent inverse association between Se and c-LDL levels in both groups; this was not the case for HOMA-IR and SLEDAI-2K. The data show the importance of assessing Se nutritional status in jSLE patients.

Salivary gland dysfunction and salivary redox imbalance in patients with Alzheimer\u2019s disease

Alzheimer’s disease (AD) is associated with the deposition of β-amyloid in the brain. AD accounts for over 50% of cases of dementia which results from disturbances in redox homeostasis. Indeed, increased intensity of protein oxidation and nitration as well as lipid peroxidation is observed in brain areas with considerable amounts of amyloid plaques and neurofibrillary tangles. However, little is known about the oxidoreductive balance of salivary glands in AD patients. Therefore, the aim of this study was to evaluate the antioxidant barrier and oxidative/nitrosative stress biomarkers in stimulated saliva and blood of AD patients. The study was participated by 25 AD patients and 25 non-demented controls without neurological diseases or cognitive impairment, matched by age and gender to the study group. The number of patients was determined based on a previous pilot study (test power = 0.9). We found a significant decrease in the activity of erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx), increased activity of catalase (CAT) and reduced concentration of plasma non-enzymatic antioxidants (uric acid, UA and reduced glutathione, GSH). In contrast, in the stimulated saliva of AD patients we observed significantly decreased activity of all antioxidant enzymes (SOD, CAT and GPx) as well as concentration of GSH compared to the control group. The content of lipid (malondialdehyde, MDA) and protein (advanced oxidation protein products, AOPP; advanced glycation end-products, AGE) oxidation products as well as biomarkers of nitrosative stress (peroxynitrite, nitrotyrosine) was significantly higher in both saliva and plasma of AD patients compared to the controls. In AD patients, we also observed a considerable decrease in stimulated saliva secretion and salivary total protein content, and an increase in salivary β-amyloid concentration. In conclusion, AD results in redox imbalance towards oxidative reactions, both at the level of the oral cavity and the entire body. General redox balance disturbances do not coincide with salivary redox balance disturbances. Reduction in stimulated saliva secretion in AD patients reflects secretory dysfunction of the parotid glands.