Glutathione S-transferase activity in acetochlor, atrazine and oxyfluorfen metabolization in maize (Zea mays L.), sorghum (Sorghum bicolor L.) and wheat (Triticum aestivum L.) (Poaceae)

This experiment was conducted to evaluate the acetochlor, atrazine and oxyfluorfen herbicides plant selectivity, in relation to glutathione S-transferase activity (GST) in maize (Zea mays L.), sorghum (Sorghum bicolor L.) and wheat (Triticum aestivum L) (Poaceae) plants. GST activity was detected 24, 48 and 72 hours after treatment applications. The experiment's treatments consisted of spraying plants with water (control), acetochlor (3 L.ha -1), atrazine (4 L.ha -1) and oxyfluorfen (1 L.ha -1). The highest GST activities were observed in presence of acetochlor, mainly at 48 hours after treatment. These increments were 105, 148 and 118% when compared to maize, sorghum and wheat control groups, respectively. It is suggested that the GST may have a role in acetochlor degradation and it may be a reason for this herbicide's selectivity in these crops.

Dietary restriction: Metabolic shifting for cardiac health

Purpose: To determine the effect of dietary restriction on metabolic pathways and the relationship of the metabolic shifting on antioxidant enzymes in cardiac tissue. Design: Randomized, controlled study. Male rats at 60 days old were randomly divided into four groups. Materials and Methods: The rats of control groups C30 and C60 were given free access to the diet over 30 and 60 days. The rats of the DR30 group were fed 60% of the chow consumed by the control groups over 30 days. The animals of the DR60 group ate 60% of the amount consumed by the C60 group over 60 days. Serum was used for total protein, lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Protein, glycogen, total lipids, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), LDH, AST and ALT were determined in cardiac tissue. Results: Dietary restriction induced diminished serum and cardiac LDH activities. AST activities were lower in the serum and cardiac muscle of the DR60 animals. Dietary restriction induced elevated total lipid concentrations in cardiac muscle. No significant differences were observed in total protein and glycogen content among the groups. Antioxidant enzyme determinations demonstrated increased cardiac GSH-Px activities in the DR60 animals and increased SOD activities in the cardiac tissue of both feed-restricted groups. Conclusions: Dietary restriction was protective against oxidative stress in the heart by improving cardiac endogenous antioxidant defences and shifting the metabolic pathway for energy production.

Dietary restriction and fibre supplementation: Oxidative stress and metabolic shifting for cardiac health

Dietary modification ought to be the first line of strategy in prevention of the development of cardiac disease. The purpose of this study was to investigate whether dietary restriction, dietary-fibre-enriched diet, and their interactions might affect antioxidant capacity and oxidative stress in cardiac tissue. Male Wistar rats (180-200 g; n = 10) were divided into four groups: control ad libitum diet (C), 50% restricted diet (DR), fed with fibre-enriched diet (F), and 50% restricted fibre-enriched diet (DR-F). After 35 days of the treatments, F, DR, and DR-F rats showed low cholesterol, LDL-cholesterol, and triacylglycerol, and high HDL-cholesterol in serum. The DR, DR-F, and F groups had decreased myocardial lipoperoxide and lipid hydroperoxide. The DR-F and F treatments increased superoxide dismutase and glutatione peroxidase (GSH-Px). The DR treatment increased GSH-Px and catalase activities. Dietary fibre beneficial effects were related to metabolic alterations. The F and DR-F groups showed high cardiac glycogen and low lactate dehydrogenase/citrate synthase ratios, indicating diminished anaerobic and elevated aerobic myocardial metabolism in these animals. There was no synergistic effect between dietary restriction and dietary fibre addition, since no differences were observed in markers of oxidative stress in the F and DR-F groups. Dietary fibre supplementation, rather than energy intake and dietary restriction, appears to be the main process retarding oxidative stress in cardiac tissue.

Toxicity of hypercaloric diet and monosodium glutamate: oxidative stress and metabolic shifting in hepatic tissue.

The present study examines the effects of a hypercaloric diet on hepatic glucose metabolism of young rats, with and without monosodium glutamate (MSG) administration, and the association of these treatments with evaluating markers of oxidative stress. Male weaned Wistar rats (21 days old) from mothers fed with a hypercaloric diet or a normal diet, were divided into four groups (n=6): control (C) fed with control diet; (MSG) treated with MSG (4 mg/g) and control diet; (HD) fed with hypercaloric diet and (MSG-HD) treated with MSG and HD. Rats were sacrificed after the oral glucose tolerance test (OGTT), at 45 days of treatments. Serum was used for insulin determination. Glycogen, hexokinase(HK), glucose-6-phosphatase(G6PH), lipid hydroperoxide, superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) were determined in liver. HD rats showed hypoglycemia, hyperinsulinemia, and high hepatic glycogen, HK and decreased G6PH. MSG and MSG-HD had hyperinsulinemia, hyperglycemia, decreased HK and increased G6PH in hepatic tissue. These animals had impaired OGTT. HD, MSG and MSG-HD groups had increased lipid hydroperoxide and decreased SOD in hepatic tissue. Hypercaloric diet and monosodium glutamate administration induced alterations in metabolic rate of glucose utilization and decreased antioxidant defenses. Therefore, the hepatic glucose metabolic shifting induced by HD intake and MSG administration were associated with oxidative stress in hepatic tissue.

Baccharis dracunculifolia, the main source of green propolis, exhibits potent antioxidant activity and prevents oxidative mitochondrial damage

Baccharis dracunculifolia DC (Asteraceae) is the main botanical source used by honeybees to produce Brazilian green propolis whose hepatoprotective properties have been already described. In this work we investigated the protective effects of the glycolic extract of B. dracunculifolia (GEBd) against oxidative stress in isolated rat liver mitochondria (RLM). The GEBd was prepared by fractionated percolation using propylene glycol as solvent. The total phenols and flavonoids, which are substances with recognized antioxidant action, were quantified in GEBd and the phytochemical analysis was carried out by HPLC. GEBd exhibited significant scavenger activity towards DPPH radicals and superoxide anions in a concentration-dependent manner, and also a Fe 2+ chelating activity. GEBd decreased the basal H 2O 2 generation and the Fe 2+- or t-BuOOH-induced ROS production in isolated mitochondria. Lipid oxidation of mitochondrial membranes, protein thiol groups and GSH oxidation were also prevented by GEBd. This shows that B. dracunculifolia exhibit potent antioxidant activity protecting liver mitochondria against oxidative damage and such action probably contribute to the antioxidant and hepatoprotective effects of green propolis. © 2011 Elsevier Ltd.

Diabetes mellitus triggers oxidative stress in the liver of alloxan-treated rats: A mechanism for diabetic chronic liver disease

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação bioquímica, morfológica e funcional do músculo estriado esquelético de ratos na insuficiência cardíaca

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da inibição da NADPH oxidase sobre o redemodelamento cardíaco de ratos com diabetes mellitus

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Avaliação da proteção gástrica e duodenal do monoterpeno nerol em roedores

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do estresse oxidativo no sangue e na placenta de ratas com diabete de intensidade moderada

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da hipóxia em respostas bioquímicas de mexilhões Perna pernaexpostos ao biodiesel B5

Pós-graduação em Biologia Animal - IBILCE

Efeito de programa para mudança do estilo de vida sobre indicadores sanguíneos dos estresses inflamatórios e oxidativo em adultos portadores de componentes da síndrome metabólica

Pós-graduação em Patologia - FMB

Avaliação de genotoxicidade e estresse oxidativo em profissionais recém-expostos aos resíduos de gases anestésicos

Pós-graduação em Cirurgia Veterinária - FCAV

Expression of P-glycoprotein, multidrug resistance-associated protein, glutathione-S-transferase pi and p53 in canine transmissible venereal tumor

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência do resveratrol sobre metabolismo energético, estresse oxidativo e expressão SIRT1 no miocárdio de ratos diabéticos

Pós-graduação em Ciências Biológicas (Farmacologia) - IBB