GCG and diabetes mellitus: Possible underlying mechanisms include alleviated oxidative stress and cardiomyocytes apoptosis by GLP-1, prevention of micro-vascular diseases related to diabetes, protection of cardiac micro-vascular endothelial cells against hypoxia/re-oxygenation injury, regulation of calcium homeostasis and electrophysiological activities of cardiomyocytes [12, 13, 15–19].