Exercise Mitigates Aberrant Mitophagy and Cardiovascular Remodeling in Diabetes

Abstract

Previously, we reported aberrant mitophagy contributed to cardiac failure and inhibition of mitochondrial fission was cardioprotective. Cardiac connexins (Cxs), play crucial role in ischemic preconditioning, myocyte coupling, and serve to regulate post ischemic cardiac dysfunction and apoptosis. Diabetic cardiomyopathy is associated with abnormal mitophagy and decreased Cxs expression. Although moderate exercise is reported to be beneficial in cardiovascular diseases, it is not known whether exercise can mitigate aberrant mitophagy and induce Cxs in diabetic cardiomyopathy. We hypothesize that exercise decreases the aberrant mitochondrial fragmentation (mitophagy), increases Cx-37, -43 expression and attenuates cardiovascular dysfunction in diabetes. To verify our hypothesis, we used db/db obese type 2 diabetic and control mice. Mice underwent 8 wks of moderate exercise on treadmill. Blood pressure (BP) by tail cuff method showed decreased mean BP and echocardiography demonstrated improved left ventricula...