EDN1 and atherosclerosis: Considering laboratory findings, metformin improves insulin sensitivity and glucose tolerance, modifies liver enzymes [75, 77] and lipid profile [76, 78, 79], reduces serum level of free androgens [75], and modifies risk factors for atherosclerosis and cardiovascular events such as plasminogen activator inhibitor-1 [80], endothelin-1 [13], and c-reactive protein [81].