A1904 Metabolic surgery remits diabetic cardiomyopathy through shifting cardiac metabolic pattern in rats

Abstract

Objectives: Diabetic cardiomyopathy (DC) is a severe complication of diabetes mellitus (DM), but effective treatments for DC are lacking. Roux-en-Y bypass surgery (RYGB) has been shown to be the most durable and effective treatment for DM and its complications. We examined if RYGB can improve DC and explore its potential mechanism in DM rats. Methods: DC was induced by streptozocin injection in Sprague–Dawley rats. RYGB was undertaken 4 weeks after streptozocin injection. Cardiac structure and function were determined by echocardiography. Cardiac ultrastructure was assessed by transmission electron microscopy. Mitochondrial function and mitochondrial supercomplexes in cardiac tissues were examined. Results: RYGB remitted hyperglycemia in STZ-induced DM rats rapidly. Compared with DM rats without RYGB, cardiac dysfunction was improved significantly 4 weeks after RYGB. Cardiac hypertrophy and myocardial fibrosis were ameliorated considerably in DM rats after RYGB. Mitochondria of DM rats were swollen and cristae absent, and myocardial fibers exhibited breaks and structural change. Cardiac mitochondrial function was improved significantly and the number of mitochondrial supercomplexes increased. Compared with DM rats without surgery, RYGB inhibited fatty-acid metabolism and related pathways according to mRNA microarray chip analysis, and these data were verified by measurement of expression of mRNA and protein. Conclusion: RYGB improved DM-related cardiac damage significantly through improvement of mitochondrial function and metabolism in the hearts of DM rats.