STZ-induced diabetic rats treated with vildagliptin (1 mg/kg/day) for 12 weeks improved cardiac function and glucose uptake, suggesting that GLP-1 could protect the cardiac microvessels against oxidative stress, apoptosis, and the resultant microvascular barrier dysfunction in diabetes, en route to improved cardiac diastolic function and cardiac glucose metabolism. The gene discussed is GCG; the disease is diabetes mellitus.