Eects of Simvastatin Treatment on Oxidant/Antioxidant State and Ultrastructure of Diabetic Rat Myocardium

Abstract. In the present study we investigated the eects of simvastatin treatment on lipid metabolism and peroxidation, antioxidant enzyme activities and ultrastruc-ture of the diabetic rat myocardium. Diabetes was induced by single injection of streptozotocin (45 mg/kg i.p.). Eight weeks after induction of diabetes, a sub-group of control and of diabetic rats was treated with simvastatin for 4 weeks (10 mg/kg/day, orally). Blood glucose, plasma cholesterol and triacylglycerol, as well as levels of cardiac thiobarbituric acid reactive substances (TBARS) were signif-icantly increased in diabetic rats. The activities of antioxidant enzymes, catalase (CAT) and glutathione peroxidase (GSHPx), were also elevated in the diabetic myocardium. Treatment with simvastatin markedly reduced serum triacylglycerol and cholesterol, and partially controlled hyperglycemia in diabetic animals. The increased activation of antioxidant enzymes and the excess of lipid peroxidation measured by TBARS were completely reversed by simvastatin treatment. Diabetic rats displayed ultrastructural ischemia-like alterations of cardiomyocytes and cap-illaries, which support oxidative stress-induced tissue remodelling. In the diabeti