Relação entre estresse oxidativo e oesteopenia diabética em ratas pré-menopausadas

The relationship between lipid peroxidation, antioxidant defense and diabetic osteopenia remains unclear. This study evaluated the relationship between lipid peroxidation index, antioxidant defense parameter and bone metabolism in a premenopausal diabetic model by measurements such as thiobarbituric acid-reactive substances concentration (TBARS) and reduced glutathione (GSH) content in brain homogenates, histomorphometric analysis, biomechanical testing and bone mineral density (BMD). Female Wistar rats with regular estrous cycle were divided into two groups: Group 1: control rats (n = 15) and Group 2: diabetic rats (n = 15). Diabetes mellitus was induced by alloxan and confirmed by glycemia 250 mg/dL. The experimental period understood 1 and 5 after days induction and 45, 75 and 120 days after the installation of diabetes mellitus.The lipid peroxidation index, measured by TBARS concentration, showed a significant increase (p<0.05) in diabetic animals in comparison to animals control. However, the antioxidant parameter, measured by GSH content, was significantly decrease (p<0.05) in diabetic animals. Histomorphometric analysis showed a significant increase (p<0.05) in femoral trabecular separation together with a significant decrease (p<0.05) in trabecular thickness and reduced trabecular bone volume in diabetic rats. Moreover, biomechanical testing and BMD values were significant decrease (p<0.05) in diabetic group. Thus, our results demonstrated that increased lipid peroxidation and altered antioxidant defense could be related to the development of oxidative stress and diabetic osteopenia in premenopausal rats

Avaliação dos efeitos da atividade física na prevenção do estresse oxidativo e do câncer de mama

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Avaliação dos parâmetros de estresse oxidativo no lúpus eritematoso

OBJECTIVE: The aim of this work was to analyse some oxidative stress parameters in patients of Systemic Lúpus Erythematosus. PATIENTS AND METHODS: Determinations of reduced glutathione content in whole blood were carried out. The activity of superoxide dismutase, gluthatione peroxidase and catalase in erythrocytes and the concentration of reactive substances of acid thiobarbituric in plasma of patients female (n =19) with SLE no activity of disease (Mex-SLEDAI < 2), with average ages of 32 ± 11 years, through the spectrophotometrical methods and from healthy individuals (n =30). Statistical data were analyzed by student t-test, p<0,05. RESULTS: Our data indicated a significant decrease on the activity of catalase and significant increase on the concentration of reactive substances of acid thiobarbituric in patients with SLE comparing with healthy individuals. There was no significant difference in other parameters. CONCLUSION: The results showed that oxidative stress has a role in the pathogenesis of the disease in SLE, even in patients without active disease.

Efeito do ácido alfa-lipóico sobre biomarcadores de estresse oxidativo, inflamação e fatores de risco cardiovascular em hipertensos

Alpha-lipoic acid (ALA) is a potent antioxidant with favourable anti-inflammatory, metabolic and endothelial effects, and has been widely investigated due to its potential against cardiovascular risk factors. This study aimed to evaluate the effect of oral ALA supplementation on oxidative stress biomarkers, inflammation and cardiovascular risk factors in patients with hypertension. This is a double-blind placebo-controlled randomized clinical trial, where the intervention was evaluated prospectively comparing results in both groups. The sample consisted of 64 hypertensive patients who were randomly distributed into ALA group (n = 32), receiving 600 mg / day ALA for twelve weeks and control group (n = 32), receiving placebo for the same period. The following parameters were evaluated before and after intervention: lipid peroxidation, content of reduced glutathione (GSH), enzymatic activities of glutathione peroxidase (GPx) and superoxide dismustase, ultrasensitive C-reactive protein (hs-CRP), triglycerides, total cholesterol and fractions, fasting glucose and anthropometric indicators. There was a statistically significant reduction (p <0.05) in serum concentrations of total cholesterol, very low density lipoprotein (VLDL), high density lipoprotein (HDL), triglycerides and blood glucose. There was a reduction in body weight and waist, abdominal and hip circumferences in the group that received ALA. In addition, there was a statistically significant increase (p <0.05) in the contents of reduced glutathione (GSH) and glutathione peroxidase (GPx) in the group receiving ALA. Oral administration of ALA appears to be a valuable adjuvant therapy, which may contribute to decrease the damage caused by oxidative stress and other risk factors associated with the atherosclerotic process

Análise das mudanças no perfil protéico durante o estresse oxidativo in vivo e atuação da MutY-Glicosilase em respostas celulares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Estresse oxidativo e aumento da apoptose em neutrófilos de cães com azotemia pré-renal

O presente trabalho tem como objetivo testar a hipótese de que, à semelhança do que ocorre na uremia, cães com azotemia pré-renal sofrem estresse oxidativo, o qual está relacionado com alterações do metabolismo oxidativo e apoptose dos neutrófilos. Para tal, foi determinada a peroxidação lipídica pela quantificação do malondialdeído (MDA) e o status antioxidante total do plasma de 15 cães normais e 10 com azotemia pré-renal, correlacionando-os com a produção de superóxido e o índice apoptótico dos neutrófilos. As determinações do MDA e do status antioxidante total foram estabelecidas empregando-se um conjunto de reagentes comerciais. Por meio de citometria de fluxo capilar, a produção de superóxido e a apoptose de neutrófilos isolados de sangue periférico foram determinadas utilizando-se a sonda hidroetidina e o sistema anexina V-PE, respectivamente. Cães azotêmicos (26,29±5,32g/L) apresentaram menor concentração (p=0,0264) do antioxidante albumina em relação ao grupo-controle (30,36±3,29g/L) e também uma menor (p=0,0027) capacidade antioxidante total (2,36±0,32 versus 2,73±0,24mmol/L), enquanto não houve alteração da peroxidação lipídica plasmática e da produção de superóxido neutrofílica. Concluiu-se que, à semelhança do que ocorre na uremia, condições azotêmicas pré-renais no cão causam estresse oxidativo e aceleração da apoptose dos neutrófilos.

Estresse oxidativo nos estágios finais da doença renal crônica em pequenos animais

The chronic kidney disease (CKD) it is characterized by irreversible structural lesions that can develop progressively for uremia and chronic renal failure (CRF). In the CRF it happens the incapacity of executing the functions of maintenance of the electrolyte balance and acid-base, catabolitos excretion and hormonal regulation appropriately. When the mechanism basic physiopathology of the renal upset is analyzed, it is observed that present factors, predispose to the unbalance oxidative. Most of the time, the renal patient comes badly nurtured, with lack in reservations of vitamins and minerals, what reduces the antioxidant defense mechanisms, what favors the installation of the renal oxidative stress, with the formation of species you reactivate of reactive oxygen species (ROS), substances these potentially harmful to the organism. The reduction of the glomerular filtration rate (GFR) in the evolution of CKD in dogs and cats is a component for the installation of the renal oxidative stress. The ROS possesses important action in the kidneys, and these substances are highly reactivate, and when presents in excess damage lipids, proteins, DNA and carbohydrate, driving functional and structural abnormalities taking the cellular apoptosis and necrosis. Against the harmful potential action of these substances you reactivate, she becomes fundamental a delicate control of his production and consumption in the half intracellular, in other words, a balance of his concentration intra and extracellular. That is possible due to the activity of the antioxidants. Like this, to present literature revision had as objective describes the participation of the oxidative stress in CRF, as well as the mechanisms defenses against the harmful action of those substances.

Avaliação do estresse oxidativo no sangue de consumidores habituais de suco de laranja

Two biomarkers of oxidative stress were evaluated in healthy volunteers treated with daily doses of orange juice that is well known source of vitamin C and citric flavanones, which have been associated with antioxidant, anti-inflammatory and hypolipidemic effects. The antioxidant capacity in the blood serum was evaluated by studying the scavenging of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) free radical, and also lipid peroxidation was evaluated by the thiobarbituric acid reacting substances (TBARS) assay. The results have shown that the regular consumption of orange juice increased 150% and 200% the serum antioxidant capacity for women and men respectively, but it was no significant change in the serum lipid peroxidation. In conclusion, the increase of flavonones and vitamin C in the body due to the regular intake of orange juice expressively improved the antioxidant capacity, but without significant effect on the lipid peroxidation.

Avaliação clínica, laboratorial e dos marcadores bioquímicos do estresse oxidativo hepatocelular em ratos diabéticos induzidos pela aloxana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Programa de exercícios físicos: análise dos fatores de risco cardiovaculares e biomarcadores de inflamação e estresse oxidativo em diabéticas exercitadas e não exercitadas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estresse oxidativo em ratos exercitados em diferentes intensidades

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

Estudo comparativo do estresse oxidativo entre tilápias (Oreochromis niloticus) e cascudos (Pterygoplichthys anisitsi) expostos a óleo diesel e a biodiesel

Pós-graduação em Biologia Animal - IBILCE

Efeitos do hormônio de crescimento sobre o metabolismo energético e estresse oxidativo no miocárdio de ratos portadores de insuficiência cardíaca secundária à estenose aórtica

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

Estresse oxidativo em equinos participantes de prova de enduro de 80 Km

Pós-graduação em Medicina Veterinária - FCAV