Cardioprotective effect of epigallocatechin-3-gallate against myocardial infarction in hypercholesterolemic rats.

Cardiovascular diseases are closely associated with a high-cholesterol or high-fat diet. The aim of the present study was to investigate the cadioprotective effect of epigallocatechin-3-gallate (EGCG) in high-fat diet-fed rats, with special emphasis on myocardial infarction. A high-fat diet was administered to male Wistar rats for 45 days and the rats of the treatment group were administered EGCG via intraperitoneal injection for the last 15 days. The serum lipid profile, antioxidant enzyme activity, lipid peroxidation, lipid metabolic proteins and cardiac tissue markers were assessed. The myocardium and aorta were also histopathologically examined. The high-fat diet-fed rats were found to be hypercholesterolemic or exhibited abnormal values in the selected parameters. However, these abnormalities were reversed to near-normal values in the rats administered EGCG. Similarly, the enzymatic antioxidant activity and non-enzymatic antioxidant levels were improved with EGCG treatment in high-fat diet-fed rats. In addition, EGCG activated sirtuin 1, endothelial nitric oxide synthase and AMP-activated protein kinase α, which suggests that its protective effect is mediated through the stimulation of lipid metabolism. The histopathological examination further revealed that EGCG significantly prevented the development of tissue abnormalities and improved the morphology of myocardial tissue. Taken together, our results suggested that EGCG plays a significant role in the protection of the cardiovascular system against the high-fat diet. This is a preliminary study, emphasizing on the cardioprotective properties of EGCG. We are currently analyzing the molecular mechanism underlying the protective effects of EGCG.