The protective role of vitamin E and angiotensin II receptor blocker in diabetic cardiomyopathy in male albino rats

Abstract

Background Diabetic cardiomyopathy is a common complication of diabetes mellitus. There are many pathophysiological mechanisms of diabetic cardiomyopathy, such as apoptosis and oxidative stress. Aim This study was designed to assess the issue of cardiomyocyte apoptosis as a possible cause of diabetic cardiomyopathy and the use of vitamin E as an antioxidant and losartan as an angiotensin II receptor blocker in suppressing this apoptosis. Materials and methods Rats were randomly divided into five groups of 10 animals each: group 1 included healthy control rats; group 2, the diabetic group, included rats that were made diabetic with a single injection of streptozotocin; group 3 included diabetic rats treated with losartan; group 4 included diabetic rats treated with vitamin E; and group 5 included diabetic rats treated with losartan and vitamin E. At the end of the experimental period, plasma glucose and serum lipid profile were evaluated. The heart rate and mean systemic arterial blood pressure were measured in all groups. Oxidative stress as assessed with malondialdehyde and reduced glutathione (GSH-PX) concentrations, as well as caspase-3 activity as an index of apoptosis, was determined in cardiac tissue. In addition, cardiac apoptosis was measured with the BCL-X immunohistochemistry technique. Results Administration of vitamin E and losartan caused significant decrease in apoptosis. In addition, there was significant decrease in malondialdehyde and caspase-3 and significant increase in GSH in cardiac tissue homogenate, with significant decrease in the serum lipid level. The mean systemic arterial blood pressure was significantly decreased, whereas heart rate increased to normal level. Conclusion Vitamin E and losartan have a protective effect on diabetes-induced cardiomyopathy in rats.