Lower Glutathione Peroxidase Activity Research Articles

Inflamma-miRs Profile in Myelodysplastic Syndrome Patients.

Etiological factors involved in myelodysplastic syndrome (MDS) include immunologic, oxidative stress and inflammatory factors, among others, and these are targets for microRNAs (miRNs). Here, we evaluated whether some miRNs may affect tumor development comparing untreated and 5-azacitidine (5-AZA) MDS-treated patients. Peripheral blood samples were collected from 20 controls and 24 MDS patients, and selected miRNs related to redox balance and inflammation (inflamma-miRs), including miR-18a, miR-21, miR-34a and miR-146a, were isolated and measured by quantitative real-time polymerase chain reaction (qRTPCR). A differential expression profile of miRNs was detected in untreated MDS patients and the 5-AZA group. Inflammation increases miRNs and, specifically, miR-18a, miR-21 and miR-34a were significantly overexpressed in untreated MDS, compared to controls. However, we did not observe any miRN profile alteration during the progression of the disease. On the other hand, 5-AZA treatment tends to restore miRN expression levels. Relating to prognostic risk factors, high-risk MDS groups (high Revised International Prognostic Scoring System (IPSS-R), high cytogenetic risk, high molecular risk (HMR) mutations) tended to be related with higher expression levels of miR-18a and miR-34a. Higher miRN expression is correlated with lower glutathione peroxidase activity, while they are related with a higher profile of pro-inflammatory cytokines (IL-2, IL-6, IL-8, TNF-α). Although our study was limited by the low number of MDS patients included, we identified miRN deregulation involved in MDS development that could regulate redox sensors and inflammatory responses. Finally, 5-AZA treatment is related with lower miRN expression levels in MDS patients.

Effects of SGLT2 inhibition on cardiac remodeling and heart failure development in rats with aortic stenosis

Abstract Introduction Aortic stenosis prevalence has been increasing as population ages. Currently, no medical therapies influence the natural history of aortic stenosis. Sodium glucose co-transporter 2 inhibitors (SGLT2i) have reduced heart failure hospitalization and cardiovascular mortality in heart failure patients with both reduced and preserved ejection fraction. The aim of this study was to evaluate the effects of SGLT2 inhibitor empagliflozin (EMPA) on cardiac remodeling and heart failure development in aortic stenosis rats. Methods Eighteen weeks after supra-aortic banding surgery, male Wistar rats were divided in four groups: Sham (n=15); sham + EMPA (Sham-EMPA, n=16); aortic stenosis (AS, n=27); and aortic stenosis + EMPA (AS-EMPA, n=27). Empagliflozin (10 mg/kg/day) was added to rat chow for 8 weeks. Echocardiogram was performed to evaluate cardiac structure and function. Myocardial collagen content was quantified by histology; activity of antioxidant enzymes and enzymes involved in energy metabolism was assessed by spectrophotometry. Protein expression was quantified by Western blot, and matrix metalloproteinase (MMP) activity by zymography. Statistical analysis: ANOVA and Bonferroni or Kruskal-Wallis and Dunn (p<0.05). Results AS-EMPA group had a lower frequency of anatomopathological heart failure features, a lower left ventricular (LV) dilatation (LV diastolic diameter: Sham 8.39±0.57; Sham-EMPA 8.25±0.38; AS 9.80±0.53; AS-EMPA 9.08±0.87 mm; LV systolic diameter: Sham 4.24±0.68; Sham-EMPA 4.19±0.57; AS 5.72±0.74; AS-EMPA 5.09±1.08 mm) and LV mass (Sham 0.85±0.11; Sham-EMPA 0.82±0.07; AS 2.19±0.27; AS-EMPA 1.76±0.34 g), and better diastolic function (isovolumetric relaxation time: Sham 28.6±2.28; Sham-EMPA 29.8±3.04; AS 18.9±2.59; AS-EMPA 22.9±5.02 ms) than AS. Systolic function was impaired in both AS and AS-EMPA compared to their respective controls and did not differ between AS-EMPA and AS. AS and AS-EMPA had larger myocyte diameter, higher interleukin-6 protein expression and lower catalase activity than Sham and Sham-EMPA, respectively. AS and AS-EMPA groups had lower enzyme activity from energy metabolism than their respective controls. AS presented higher lipid hydroperoxide concentration, collagen III and p65 NF-kB protein expression, and lower glutathione peroxidase activity than Sham. AS-EMPA had higher collagen I expression and inactive MMP-2 than Sham-EMPA. AS-EMPA presented higher glutathione peroxidase and intermediary active MMP-2, and lower interstitial collagen fraction (Sham 2.68±0.59; Sham-EMPA 3.16±0.33; AS 5.68±0.97; AS-EMPA 3.55±0.70 %) than AS. Conclusion Empagliflozin improves cardiac remodeling, diastolic function and myocardial oxidative stress, and reduces heart failure feature frequency and interstitial collagen fraction in aortic stenosis rats.

Relationship Between Plasma Fluoride Levels, Glutathione Peroxidase Activity, Hemoglobin, and Abortion in Rural and Urban Pregnant Women from Settat (Morocco)

Background: This study aimed to investigate the relationship between plasma fluoride and hemoglobin levels, glutathione peroxidase (GPx) activity, and abortion among rural and urban pregnant women from Settat province (Morocco). Methods: Blood samples were collected from rural pregnant women who had not undergone abortion (N = 224), rural pregnant women who had an abortion (N = 38), urban pregnant women who had not undergone abortion (N = 163), and urban pregnant women who had an abortion (N = 14). Results: The highest (p < 0.01) plasma fluoride levels and the lowest (p < 0.01) GPx activity were observed in rural pregnant women. In all participants, plasma fluoride levels were significantly higher (p < 0.001), and the GPx activity was significantly (p < 0.001) lower in pregnant women who had an abortion compared with those who did not undergo such process. No significant difference was observed between the hemoglobin levels of all participants. Furthermore, abortion was positively correlated with plasma fluoride levels (p < 0.001) and negatively correlated with GPx activity (p < 0.001) in rural participants. Conclusions: Rural pregnant women had higher plasma fluoride levels and lower GPx activity, which correlated with the increased abortion risk and oxidative stress.

Determination of glutathione peroxidase activity and oxidized/reduced glutathione ratio in patients with colon cancer

Colon cancer (CC) is accepted as the third type of cancer that causes death in the world. Oxidative stress and low glutathione peroxidase (GPx) activity can cause CC. This study aims to show whether GPx and Oxidized (GSSG)/ reduced glutathione (GSH) levels, which are considered oxidative stress markers, are effective in the etiopathogenesis of CC. Erythrocyte isolation was performed in 3 ml blood sample taken from volunteers aged 18-75 years. Hemoglobin amounts were determined from the standard graph drawn by monitoring the conversion of methemoglobin to cyanmethemoglobin in the presence of cyanide at 540 nm. Glutathione peroxidase activity was determined by spectrophotometric monitoring of NADPH+H+ (reduced nicotinamide adenine dinucleotide phosphate) oxidation at a wavelength of 340 nm. The amounts of oxidized and reduced glutathione were determined by using the standard graph drawn by following the 412 nm wavelength of the formation of 2-nitro-5-thiobenzoic acid, which has a yellow color. GPx activity of individuals with CC is 5.64 ± 1.49 U/gHb, GSH concentration is 6.96 ± 1.45 nmol/gHb, and GSH/GSSG ratio is 1.04 ± 0.49, GPx activity of healthy individuals is 10.52 ± 2.22 U/gHb, GSH concentration 11.43 ± 1.90 nmol/gHb, and GSH/GSSG: 3.86 ± 1.30, that is, the values of the patient group were significantly lower than the control group. Current results suggest that GPx activity, GSH concentration and GSH/GSSG ratio can be used as CC markers in the diagnosis and monitoring of disease course, and that the decrease in these parameters may be associated with an increased risk of CC.

Selenium and Redox Enzyme Activity in Pregnant Women Exposed to Methylmercury.

Selenium (Se) is a micronutrient with essential physiological functions achieved through the production of selenoproteins. Adequate Se intake has health benefits and reduces mercury (Hg) toxicity, which is important due to its neurotoxicity. This study determined the Se status and redox enzyme, including selenoproteins', activity in pregnant women highly exposed to Hg (between 1 to 54 µg Hg/L blood) via fish consumption. A cross-sectional study enrolling 513 women between the first and third trimester of pregnancy from Madeira, Portugal was conducted, encompassing collection of blood and plasma samples. Samples were analyzed for total Se and Hg levels in whole blood and plasma, and plasma activity of redox-active proteins, such as glutathione peroxidase (GPx), thioredoxin reductase (TrxR) and thioredoxin (Trx). Enzyme activities were related to Se and Hg levels in blood. Se levels in whole blood (65.0 ± 13.1 µg/L) indicated this population had a sub-optimal Se status, which translated to low plasma GPx activity (69.7 ± 28.4 U/L). The activity of TrxR (12.3 ± 5.60 ng/mL) was not affected by the low Se levels. On the other hand, the decrease in Trx activity with an increase in Hg might be a good indicator to prevent fetal susceptibility.

Effects of tannic acid on growth performance, relative organ weight, antioxidative status, and intestinal histomorphology in broilers exposed to aflatoxin B1.

A total of 480 one-day-old AA broiler chicks were randomly allocated to one of four treatments in a 2 × 2 factorial to investigate the effects of tannic acid (TA) on growth performance, relative organ weight, antioxidant capacity, and intestinal health in broilers dietary exposed to aflatoxin B1 (AFB1). Treatments were as follows: (1) CON, control diet; (2) TA, CON + 250 mg/kg TA; (3) AFB1, CON + 500 μg/kg AFB1; and (4) TA+AFB1, CON + 250 mg/kg TA + 500 μg/kg AFB1. There were 10 replicate pens with 12 broilers per replicate. Dietary AFB1 challenge increased the feed conversion ratio during days 1 to 21 (P < 0.05). The TA in the diet did not show significant effects on the growth performance of broilers during the whole experiment period (P > 0.05). The liver and kidney relative weight was increased in the AF challenge groups compared with the CON (P < 0.05). The addition of TA could alleviate the relative weight increase of liver and kidney caused by AFB1 (P < 0.05). Broilers fed the AFB1 diets had lower activity of glutathione peroxidase, catalase, total superoxide dismutase, S-transferase, and total antioxidant capacity in plasma, liver and jejunum, and greater malondialdehyde content (P < 0.05). Dietary supplemented with 250 mg/kg TA increased the activities of antioxidative enzymes, and decreased malondialdehyde content (P < 0.05). In addition, AFB1 significantly reduced the villus height and crypt depth ratio in the ileum on day 42 (P < 0.05). In conclusion, supplementation with 250 mg/kg TA could partially protect the antioxidant capacity and prevent the enlargement of liver in broilers dietary challenged with 500 μg/kg AFB1.

Oxidative balance disorders as a factor of formation and progression of hypoandrogenism in boys

Objective — to study the features of the state of oxidative balance (processes of free radical oxidation and antioxidant protection) in boys with hypoandrogenism (HA). Materials and methods. Examinations involved 103 adolescent boys agreed 14 to 17 years with the delayed sexual development. Serum levels of total testosterone (TT), conjugated dienes (CD), thiobarbituric acid­reactive substance (TBARS), carbonylated proteins, reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) activity were determined. The coefficient of oxidative stress was calculated. Results and discussion. The following indicators have been revealed in patients with the delayed sexual development vs the comparison group: increased CD levels in 84.0 % of patients, elevated levels of carbonylated proteins in 53.7 % of adolescents, one third had raised TBARS levels; 63.0 % of patients demonstrated the increased GSH levels. Decreased activity of GPx and CAT was registered in more than half of the patients. Such changes indicate an imbalance in the ratio of free radical oxidation (FRO) and antioxidant protection, which leads to the state of OS in adolescents with delayed puberty.It was found that the redox balance in adolescents with delayed puberty significantly depends on the degree of androgen deficiency. Half of the patients with a degree I and II HA and 24.5 % of boys with degree III HA had elevated TBARS levels, which is more common in adolescents with normative values of TT. At the highest degree of androgen deficiency, the frequency of normative values of carbonylated proteins decreased. Most boys had elevated levels of CD (80 %), regardless of the degree of HA. An increase in SOD activity was found in patients with degree III HA. Low SOD activity was registered in 28.6 % of patients with degree II HA and 29.6 % with degree III HA, which is much less common compared to patients with normal TT levels. Most patients with HA, regardless of degree, were characterized by low GPx activity. Decreased CAT activity was registered in 76.9 % of patients with degree II HA. The majority of patients with HA (from 60.9 to 90 %) showed elevated levels of GSH, regardless of degree. The progression of HA in adolescents is characterized by the accumulation of products of free radical oxidation of lipids and an imbalance in the enzymatic and low molecular parts of the antioxidant system. This is typical for HA II and III degrees. The largest number of correlations was found in patients with degree III HA, testifying the formation of oxidative stress due to the activation of lipid peroxidation with simultaneous tension of the antioxidant defense system. Conclusions. The progression of HA is accompanied by the accumulation of products of free radical oxidation of lipids with simultaneous depletion of the enzymatic part of the antioxidant defense system. The activating effect of testosterone deficiency on the formation of oxidative stress in adolescents with the highest degree of androgen deficiency has been proven. This makes it possible to assess the state of oxidative balance as a factor in the formation and progression of HA in adolescents.

Impaired Antioxidant Defence Status Is Associated With Metabolic-Inflammatory Risk Factors in Preterm Children With Extrauterine Growth Restriction: The BIORICA Cohort Study.

Introduction: An impaired antioxidant status has been described during foetal growth restriction (FGR). Similarly, the antioxidant defence system can be compromised in preterm children with extrauterine growth restriction (EUGR). The aim of this prospective study was to evaluate the antioxidant status in prepubertal children with a history of prematurity without FGR, with and without EUGR, compared to a healthy group.Methods: In total, 211 children were recruited and classified into three groups: 38 with a history of prematurity and EUGR; 50 with a history of prematurity and adequate extrauterine growth (AEUG); and 123 control children born at term. Catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were assessed in lysed erythrocytes with spectrophotometric methods. Plasma levels of the antioxidants α-tocopherol, retinol and β-carotene were determined through solvent extraction and ultra-high-pressure liquid chromatography coupled to mass spectrometry.Results: Children with the antecedent of EUGR and prematurity had lower CAT activity than the other two groups and lower GPx activity than the control children. Lower SOD, GPx and GR activities were observed in the AEUG group compared to the controls. However, higher concentrations of α-tocopherol and β-carotene were found in the EUGR group compared to the other groups; retinol levels were also higher in EUGR than in AEUG children. In EUGR and AEUG children, enzymatic antioxidant activities and plasma antioxidants were associated with metabolic syndrome components and pro-inflammatory biomarkers.Conclusions: This study reveals, for the first time, that the EUGR condition and prematurity appear to be linked to an impairment of the antioxidant defence status, which might condition an increased risk of adverse metabolic outcomes later in life.

Age-related changes in liver metabolism and antioxidant capacity of laying hens

This study aimed to investigate the age-related changes of hepatic metabolism and antioxidant capacity of laying hens at 3 different ages. A total of 192 Hy-line Brown laying hens were assigned into 3 groups: 1) 195-day-old (D195 group); 2) 340-day-old (D340 group); 3) 525-day-old (D525 group). Each group replicated 8 times with 8 hens at the same age. Higher activity of aspartate aminotransferase and lower contents of total protein and globulin were observed in the serum of 525-day-old hens in comparison with their 195-day-old counterparts (P < 0.05). The 525-day-old hens accumulated higher contents of total cholesterol and triglyceride in the liver than 195-day-old birds. Additionally, compared with hens from D195 or D340 group, 525-day-old birds exhibited a lower circulating estradiol level (P < 0.05). For antioxidant capacity, birds in the D525 group showed a higher malondialdehyde concentration in both serum and liver as compared with D195 or D340 group (P < 0.05). The 525-day-old hens also exhibited lower glutathione peroxidase activities in both serum and liver when compared with 195-day-old birds (P < 0.05). Simultaneously, there was a decline of hepatic superoxide dismutase activity in the D525 group in comparison with D195 group (P < 0.05). Compared with 195-day-old counterparts, 340-day-old birds upregulated the mRNA abundance of nuclear factor erythroid-2 related factor 2 and glutathione peroxidase 1 in the liver (P < 0.05). In contrast, hens from D525 group showed the downregulation of hepatic nuclear factor erythroid-2 related factor 2, NAD(P)H quinone dehydrogenase 1, and superoxide dismutase 1 when compared with D340 group (P < 0.05). These results indicated that increasing age can adversely affect liver metabolism and function of laying hens.

Enhancement of performance and anti-oxidant variables in broiler chicken fed diets containing sub-optimal methionine level with graded concentrations of sulphur and folic acid.

ObjectiveAn experiment was conducted to determine the effects of supplementing graded concentrations of inorganic sulphur (S) without and with folic acid (FA) in maize-soybean meal diets on performance, slaughter and anti-oxidant variables, immune responses and serum protein fractions in broiler chicken.MethodsInorganic S was supplemented at 0.05%, 0.10%, 0.15%, and 0.20% alone or in combination with FA (4 mg/kg) in basal diet (BD) containing no supplemental methionine (Met) and FA. A control group was fed with the recommended concentration of Met. Each diet was offered to 10 pens of 5 male broiler chicks (Cobb 400) and fed ad libitum from day 1 to 42.ResultsThe broilers fed the BD had lower body weight gain (BWG), feed efficiency (FE), higher lipid peroxidation (LP), lower activity of glutathione peroxidase (GSHPx), lower lymphocyte proliferation ratio (LPR), and reduced concentrations of total protein, albumin, and globulin in serum. Supplementation of FA and S to the BD improved the BWG (all concentrations of S) and FE (0.20% S) similar to the control group. Similarly, the combination of S and FA significantly improved the concentrations of total protein, albumin, and globulin in serum, reduced the LP and increased the activity of GSHPx and LPR. However, responses in the above parameters were related to the concentration of S in the diet. The slaughter variables and antibody titres against the Newcastle disease were not affected with the treatments.ConclusionBased on the results, it is concluded that the combination of S (0.2%) and FA (4 mg/kg) improved the BWG and FE, similarly supplementation of these nutrients improved the concentration of protein fractions and reduced the stress (reduced LP and improved GSHPx) variables in serum and improved the cell mediated immune response (LPR) in broilers fed sub-optimal concentrations of Met in diet.

Influence of Consumption of Orange Juice (Citrus Sinensis) on Cardiac Remodeling of Rats Submitted to Myocardial Infarction.

ResumoFundamentoO suco de laranja (SL) é rico em polifenóis com propriedades anti-inflamatórias e antioxidantes. Após o infarto do miocárdio (IM), mudanças complexas ocorrem na estrutura e na função cardíacas, processo conhecido como remodelação cardíaca (RC). O estresse oxidativo e a inflamação podem modular esse processo. Nossa hipótese foi a de que o consumo de SL atenua a RC após o IM.ObjetivosAvaliar a influência do SL sobre a RC após IM pela análise de variáveis funcionais, morfológicas, de estresse oxidativo, de inflação, e de metabolismo energético.MétodosUm total de 242 ratos machos pesando entre 200 e 250g foram submetidos a um procedimento cirúrgico (ligação da artéria coronária ou cirurgia simulada). Sete dia após a cirurgia, os animais sobreviventes foram divididos para um dos quatro grupos: 1) SM, animais sham que receberam água e maltodextrina (n= 20); 2) SSL, animais sham que receberam SL (n= 20); 3) IM, animais infartados que receberam água e maltodextrina (n= 40); e 4) ISL, animais infartados que receberam SL (n = 40). A análise estatística foi realizada pelo teste de ANOVA com dois fatores com o teste de Holm-Sidak. Os resultados foram apresentados em média ± desvio padrão, e o nível de significância adotado foi de 5%.ResultadosTrês meses depois, o IM levou à hipertrofia do ventrículo esquerdo (VE), com disfunção sistólica e diastólica, e aumento nos mediadores inflamatórios e de estresse oxidativo. Os animais que consumiram SL apresentaram menor atividade da glutationa peroxidase e maior expressão da heme-oxigenase-1 (HO-1).ConclusãoO SL atenuou a RC, e a HO-1 pode exercer um importante papel nesse processo.

Utilization of pelleted and extruded feed by blunt snout bream Megalobrama amblycephala: Insights from growth performance, health status and feed cost.

The present study was conducted to evaluate the utilization of both pelleted feed (PF) and extruded feed (EF) by blunt snout bream Megalobrama amblycephala based on growth performance, stress responses, innate immunity and disease resistance. Both the PF and EF were prepared with the same formula. Fish were divided randomly into 2 groups, including one fed the PF continuously and one offered the EF continuously. The whole feeding trial lasted 8weeks, after which fish were subjected to Aeromonas hydrophila infection. The results showed that the feed intake, feed conversion ratio, hepatic total superoxide dismutase activity and glutathione content, plasma complement 3 and complement 4 levels as well as myeloperoxidase activity of the EF group were all significantly lower than those of the PF group, while the opposite was true for the condition factor, the viscera index, the abdominal fat percentage, nitrogen and energy retention, hepatic malondialdehyde content, plasma levels of cortisol, glucose, lactate, total protein and globulin as well as the activities of plasma alanine aminotransferase and aspartate aminotransferase. In addition, the EF group also obtained relatively low activities of hepatic glutathione peroxidase and plasma acid phosphatase as well as high cumulative mortality rates at 24-96h after Aeromonas hydrophila challenge. Furthermore, the feed cost of culturing this species with EF is lower than that with PF. These findings indicated that compared with PF, EF could increase the feed utilization and economic benefits of blunt snout bream, but reduce its anti-stress ability, non-specific immunity, A. hydrophila resistance and feed cost.

Deletion polymorphism of GSTT1 gene and lipid peroxidation hyperactivation in menopausal insomnia

A comparative analysis of the parameters of lipid peroxidation - antioxidant defense system in menopausal women with- and without insomnia, depending on the GSTT1 polymorphism. The study included 181 menopausal Caucasian women (ethnic group - Russians), who according to the results of the clinical-anamnestic examinations were divided into insomnia group (n=120, age 53.68±4.61 years, body mass index 26.47±3.73 kg/m2) and control group (n=61, age 52.64±4.91 years, body mass index 27.69±3.11 kg/m2). The insomnia group was formed according to the clinical guidelines for the diagnosis and treatment of chronic insomnia in adults, and scores of the Insomnia Severity Index. The study of the GSTT1 gene polymorphism was carried out using polymerase chain reaction. The lipid peroxidation - antioxidant system parameters were determined by spectrofluorophotometric methods. In the insomnia group, carriers of the normal GSTT1 genotype had higher diene conjugates with lower glutathione peroxidase activity as compared to controls. When comparing groups of women with the deletion in GSTT1, an increase in the content of substrates and lipid peroxidation products was observed at all stages of lipid peroxidation, oxidized glutathione, glutathione S-transferase activity with a decrease in the content of reduced glutathione and retinol in the insomnia group as compared to controls. In the insomnia group, carriers of the deletion genotype had a higher content of ketodienes/conjugated trienes and active products of thiobarbituric acid, a lower content of retinol and α-tocopherol as compared to the patients with normal GSTT1 genotype. Conclusions. Insomnia in the menopausal women is accompanied with the intensification of lipid peroxidation only in the carriers of the GSTT1 deletion genotype.

Actividad glutatión peroxidasa en vacas lecheras sin suplementar y suplementadas con selenio

&lt;p&gt;El objetivo del presente trabajo fue evaluar los niveles de la actividad glutatión-peroxidasa&lt;br /&gt;(GPX) en vacas lecheras suplementadas y sin suplementar con selenio (Se) intra-ruminal.&lt;br /&gt;Se determinó la actividad GPX de 96 vacas Holstein primíparas y multíparas, clínicamente&lt;br /&gt;sanas, procedentes de un establecimiento comercial de la localidad de Centeno, Provincia de&lt;br /&gt;Santa Fe (Argentina). Se definieron dos categorías de reses según las determinaciones individuales de GPX tomando como valor de corte 130 U/gHb. Los animales de cada categoría se dividieron aleatoriamente en dos subgrupos, uno de los cuales recibió un bolo intraruminal&lt;br /&gt;de Se de larga acción (Permatrace®) mientras que el otro permaneció sin suplementar. A&lt;br /&gt;continuación, se efectuaron dos nuevas determinaciones de la actividad enzimática: preparto&lt;br /&gt;(entre los 30 y los 15 días previos al parto) y posparto (entre los 30 y los 45 posteriores al&lt;br /&gt;parto). El 35,4% de las vacas presentó valores de actividad de la enzima menores al valor de&lt;br /&gt;corte. Los animales con bajos valores basales de actividad GPX no suplementadas con bolos&lt;br /&gt;de Se, no modificaron significativamente los datos basales. En las vacas con bajos valores&lt;br /&gt;basales de actividad GPX y suplementadas con Se, se observó un aumento significativo de la&lt;br /&gt;actividad enzimática. Se concluye que una proporción importante de animales presenta baja&lt;br /&gt;actividad GPX, que los niveles de las enzimas se modifican según el momento de la evaluación&lt;br /&gt;en relación al tiempo del parto, y que la suplementación con bolos de Se intra-ruminal&lt;br /&gt;constituye una estrategia efectiva para aumentar la actividad de la enzima.&lt;/p&gt;

Hepatic oxidative stress and neurotoxicity in Pelophylax kl. esculentus frogs: Influence of long-term exposure to a cyanobacterial bloom

Although the long-term exposure of aquatic organisms to cyanobacterial blooms is a regular occurrence in the environment, the prooxidant and neurotoxic effects of such conditions are still insufficiently investigated in situ. We examined the temporal dynamics of the biochemical parameters in the liver of Pelophylax kl. esculentus frogs that inhabit the northern (N) side of Lake Ludaš (Serbia) with microcystins (MCs) produced in a cyanobacterial bloom over three summer months. The obtained data were compared with data on frogs that live on the southern (S), MC-free side of the same lake. Our results showed that the MC-producing bloom induced oxidative damage to proteins and lipids, observed as a decrease in the concentration of protein –SH groups and increased lipid peroxidation (LPO) in the liver of N frogs in comparison to S frogs. Glutathione (GSH) played a key role in the transient defense against the MC-induced development of LPO. The low glutathione peroxidase (GPx) activity detected in all groups of frogs from the N site was crucial for the observed prooxidant consequences. The bloom impaired cholinergic homeostasis as a result of a decrease in ChE activity. A delayed neurotoxic effect in relation to the prooxidant outcomes was observed. Our results also showed that even though the integrated biomarker response (IBR) of the antioxidant biomarkers increased during exposure, the individual biochemical parameters did not exhibit a well-defined time-dependent pattern because of specific adaptation dynamics and/or additional effects of the physicochemical parameters of the water. This comprehensive environmental ecotoxicological evaluation of the cyanobacterial bloom-induced biochemical alterations in the liver of frogs provides a new basis for further investigations of the prolonged, real-life ecotoxicity of the blooms.

Dietary Supplemented Curcumin Improves Meat Quality and Antioxidant Status of Intrauterine Growth Retardation Growing Pigs via Nrf2 Signal Pathway.

Simple SummaryMore than 15% of piglets and about 10% of newborn humans suffer from intrauterine growth retardation (IUGR), which refers to growth lag, developmental restriction and impaired organs in the fetus. IUGR exhibits programming consequences and exerts permanent negative effects on postnatal growth and health. Dietary supplemented curcumin, as the main natural polyphenol isolated from the natural antioxidant (turmeric), might show possible effects on antioxidant capacity, and the meat quality of IUGR pigs. Therefore, in our present study, 12 normal birth weight (NBW) and 24 IUGR neonatal female piglets were selected and fed control diets supplemented 0 (NBW), 0 (IUGR) and 200 (IUGR + Cur) mg/kg curcumin from 26 to 115 days of age (n = 12). The growth performance, meat quality, redox status and its related Nrf2 pathway were determined to test the hypothesis that curcumin may play beneficial roles against IUGR-induced oxidative stress. This study suggested that curcumin could serve as a potential natural antioxidant in nutrition interventions of IUGR offspring to enhance the redox status and improve the meat quality of leg muscles. These results attained from IUGR pig models can also provide some useful theoretical references for IUGR offspring in humans.Intrauterine growth retardation (IUGR) exhibits programming consequences and may induce oxidative stress in growing animals and humans. This study was conducted to investigate the hypothesis that dietary curcumin may protect growing pigs from IUGR-induced oxidative stress via the Nrf2 pathway. Twelve normal birth weight (NBW) and 24 IUGR female piglets were selected and fed control diets supplemented 0 (NBW), 0 (IUGR) and 200 (IUGR + Cur) mg/kg curcumin from 26 to 115 days of age (n = 12). Growth performance, meat quality, redox status and its related Nrf2 pathway were determined. Results showed that IUGR pigs exhibited decreased body weight on 0 d, 26 d and 56 d (p < 0.01) but had no difference on 115 d among NBW, IUGR and IUGR + Cur groups (p > 0.05). Compared with NBW and IUGR groups, a significant decrease in drip loss (24 h and 48 h) was observed in the IUGR + Cur group (p < 0.01). IUGR pigs had higher concentrations of malondialdehyde (MDA) (p < 0.01) and protein carbonyl (PC) (p = 0.03) and lower activities of glutathione peroxidase (p = 0.02), catalase (p < 0.01) and peroxidase (p = 0.02) in leg muscles than NBW pigs. Dietary-added 200 mg/kg curcumin decreased concentrations of MDA and PC and improved the activities of catalase, superoxide dismutase (SOD) and peroxidase as compared to the IUGR group (p < 0.05). Additionally, dietary curcumin enhanced protein (NQO1) and mRNA expression of genes (Nrf2, NQO1, gamma-glutamyltransferase 1 (GGT1), heme oxygenase-1 (HO-1), glutathione S-transferase (GST) and catalase (CAT)) as compared to the IUGR group (p < 0.05). These results suggest that dietary curcumin could serve as a potential additive to enhance redox status and improve meat quality of IUGR growing pigs via the Nrf2 signal pathway.

Serum levels of zinc, copper, selenium and glutathione peroxidase in the different groups of colorectal cancer patients.

Background:Colorectal cancer (CRC) is considered the fourth type of cancer that causes death worldwide. Changes in the levels of zinc (Zn), copper (Cu), and selenium (Se) as well as low glutathione peroxidase (GPx) activity can lead to CRC and this study was aimed to evaluate their possible use as diagnostic markers.Methods:CRC patients (n=90) were divided into three groups; newly diagnosed, before surgery, and after surgery. These groups were compared to healthy subjects (n=30); the mean age ±SD was 50.63±9.26 and 49.97±10.85 for CRC patients and healthy subjects, respectively. Biochemical study for serum levels of Zn and Cu was measured by FAAS, Se was measured by HGAAS, and ELISA for GPx.Results:Zn, Cu, Se and GPx were significantly lower in all CRC patient groups, except for the after surgery group which showed no differences for Zn and GPx as compared to the healthy subjects. Positive correlations were found between Se and Zn and between Se and GPx (r=0.71, r=0.42; P<0.01, respectively) in all CRC patient groups. A receiver operating characteristic (ROC) curve analysis was applied for the newly diagnostic group showing all the parameters that can be used as diagnostic markers for CRC.Conclusion:The present results conclude that Zn, Cu Se, and GPx can be used as diagnostic markers for CRC, where the decrease of these parameters may be associated with an increased risk of CRC and as indicators of the response to therapy.

Soybean β-conglycinin caused intestinal inflammation and oxidative damage in association with NF-κB, TOR and Nrf2 in juvenile grass carp (Ctenopharyngodon idella): varying among different intestinal segments

The current study aimed to investigate the effects and mechanisms of dietary soybean β-conglycinin in immune function and oxidative damage among different intestinal segments of juvenile grass carp (Ctenopharyngodon idella). 240 fish (13.77 ± 0.10 g) were fed control or 8% β‐conglycinin diet for 7 weeks. Dietary β-conglycinin caused inconsistent suppression effects on the innate immune by decreasing complement component, lysozyme, antimicrobial peptide and acid phosphatase among different intestinal segments. Meanwhile, dietary β-conglycinin caused inflammation in the mid and distal intestine by raising pro-inflammatory cytokines and declining anti-inflammatory cytokines mRNA levels, while more serious in the distal intestine than in the mid intestine. Furthermore, dietary β-conglycinin regulating inflammatory cytokines might be associated with transcription factors nuclear factor-κB P65 (NF-κB P65) nucleus translocation and target of rapamycin (TOR) phosphorylation in the distal intestine but only related to TOR phosphorylation in the mid intestine. Interestingly, in the proximal intestine, dietary β-conglycinin decreased both pro-inflammatory and anti-inflammatory cytokines mRNA level, and did not affect NF-κB P65 nucleus translocation and TOR phosphorylation. For oxidative damage, dietary β-conglycinin exposure elevated both malondialdehyde (MDA) and protein carbonyl (PC) contents in the distal intestine, which might be attributed to the suppression of the Mn-SOD, catalase (CAT) and glutathione peroxidase (GPx) activities. In the mid intestine, dietary β-conglycinin only increased PC content in association with the low activities of CAT, GPx and glutathione peroxidase (GR). Unexpectedly, in the proximal intestine, dietary β-conglycinin did not significantly change MDA and PC contents while decreased antioxidant enzyme activities. Furtherly, dietary β-conglycinin affect the antioxidant enzyme activity might be regulated by the varying pattern of nuclear factor-erythroid 2-related factor 2 (Nrf2) nucleus translocation among these three intestinal segments. In summary, dietary β-conglycinin caused intestinal inflammation and oxidative damage in association with NF-κB, TOR and Nrf2 signaling molecules, which were varying among the three intestinal segments of grass carp.

Interaction of oxidative stress and BDNF on executive dysfunction in patients with chronic schizophrenia

Executive dysfunction is increasingly recognized as one of the widely observed dimensions of cognitive impairments in the course of schizophrenia (SCZ). However, the potential molecular pathological mechanisms remain elusive. Previous studies have demonstrated that decreased brain-derived neurotrophic factor (BDNF) and oxidative damage may be associated with the psychopathology and cognitive impairment of SCZ. The present study aims to assess whether the interaction between BDNF and oxidative damage is involved in the disruption of executive function (EF) in patients with chronic SCZ. Serum BDNF and plasma oxidative stress markers were measured in 189 patients and 60 control subjects. EFs were evaluated by Wisconsin card sorting tests (WCST), Stroop word/color test (Stroop), and verbal fluency tests (VFT). The results showed that patients performed worse in the VFT, WCST and Stroop tests than healthy subjects. Moreover, patients had lower activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) and lower BDNF levels, but higher malondialdehyde (MDA) levels than healthy controls. In patients, BDNF was negatively correlated with SOD (p < 0.01). For patients, catalase (CAT) activity was negatively associated with WCST error score (p = 0.02) and BDNF was positively correlated to VFT score (p = 0.02). However, all these correlations between biomarkers and EF domains did not pass Bonferroni corrections. Finally, multiple regression analyses identified BDNF × SOD activity and BDNF × MDA as influencing factors for VFT score in patients (both p < 0.05). Our results highlight the complex interplay between OS parameters and BDNF in the pathophysiology of EF impairment in SCZ, consistent with its neurodevelopmental hypothesis.

Association of blood mercury levels with non-melanoma skin cancer in the United States using NHANES data from 2003-2016

PDS 63: Chemicals and metals: health effects, Exhibition Hall (PDS), Ground floor, August 27, 2019, 10:30 AM - 12:00 PM Background/Aim: Some studies have reported that mercury is associated with an increased risk of lung and esophageal cancers. However, few epidemiological studies investigated mercury exposure in relation to skin cancer risk. Mercury inactivates glutathione peroxidase (GPX) and lower GPX activity is associated with increased risk of skin cancer. Therefore, we investigated the association between blood mercury levels and skin cancer. Methods: We used National Health and Nutrition Examination Survey (NHANES) data from 2003 through 2016. Our exposures of interest were blood total (tHg), inorganic (iHg), and methyl mercury (MeHg). The main outcome was a reported diagnosis of non-melanoma skin cancer. We included participants aged ≥18 having information on exposures, outcome, and covariates (age, sex, race, BMI, smoking history, and income). We conducted logistic regression analysis adjusting for above covariates and survey year. Results: Among 30,103 participants, the median age was 48, 52% were female, 46% Non-Hispanic White, and 21% Non-Hispanic Black. A total of 477 subjects reported diagnosis of non-melanoma skin cancer; 95% of whom were Non-Hispanic White. Median levels of tHg and MeHg were 0.9 µg/L and 0.6 µg/L, respectively. A 1 µg/L increase in blood tHg was associated with 6% increased odds of non-melanoma skin cancer (OR: 1.06; 95% CI: 1.02, 1.09). Compared to subjects with tHg ≤ 0.46 µg/L, subjects with tHg >1.72 µg/L had approximately double the odds of non-melanoma skin cancer (OR: 1.93, 95% CI: 1.31, 2.84). Similarly, subjects with MeHg > 1.43 µg/L had 1.8 times greater odds of non-melanoma skin cancer (OR: 1.82, 95% CI: 1.18, 2.79) compared to subjects with MeHg ≤ 0.21 µg/L. Conclusions: We found that higher blood tHg and MeHg levels were associated with higher prevalence of non-melanoma skin cancer. Our findings add to the limited evidence from epidemiologic studies supporting the role of mercury exposures in skin cancer.