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Effect of selenium on oxidative stress and hyperglycemia in Diabetes Mellitus
2 Wondracek D. C.; 1 Barbosa, N. B. V.; 2Rocha, J. B. T.; 2Zeni, G.;
2Nogueira, C. W.
1Instituto de Ciências Biológicas, Universidade de Passo Fundo, Passo Fundo, Brazil; 2Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, CEP 97105-900, Brazil
The hyperglycemia caused by Diabetes Mellitus (DM) is associated with an increase of oxidative stress, as reflected by excessive free radical generation or by a decrease of antioxidant defenses. Selenium is an essential micronutrient that plays a crucial role as an antioxidant element. Selenium has been utilized as supplement in human patients and animals models of diabetes. This study was designed to determine the effect of diphenyl diselenide and ebselen, synthetic organoselenium compounds with antioxidant properties, in diabetic rats. Diabetes was induced by the administration of streptozotocin (STZ) (45 mg/kg, i.p). The animals were randomly divided into the following groups: (1) control; (2) Diphenyl diselenide (Ph) (3) Ebselen-(Ebs); (4) STZ; (5) STZ+(PhSe)2 (STZ/Ph) and (6) STZ+Ebselen (STZ/Ebs). Selenium groups were subcutaneously administered with diphenyl diselenide or ebselen at the dose of 1 mg/kg (once a day) for 90 days after the administration of STZ. The organoselenium compounds were dissolved in 25% Tween 80. The data were analyzed by one-way or two-way ANOVA and MANOVA analyses of variance followed by Duncan's multiple range test when appropriate. In experimental trials, diphenyl diselenide, but not ebselen, caused a significant reduction on blood glucose levels of STZ treated rats. This effect of diphenyl diselenide was accompanied by a reduction in the levels of glycated proteins. Diphenyl diselenide treatment increased superoxide dismutase (SOD) activity and vitamin C levels what were decreased in STZ-treated rats. In normal rats, diphenyl diselenide promoted per se an increase in hepatic, renal and blood GSH levels. Similarly, diphenyl diselenide caused an increase in hepatic and renal GSH levels in STZ treated rats. TBARS (thiobarbituric acid reactive species) and protein carbonyl levels were not modified by STZ and/or diphenyl diselenide and ebselen treatments. Our findings suggest that diphenyl diselenide can be considered an anti-diabetogenic agent by exhibiting anti-hyperglycemic and antioxidant properties.
CAPES, CNPq,PET
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