Recently, some researches reported that metformin (1,1-dimethylbiguanide), as the first-line hypoglycemic drugs for the treatment of T2DM, can prevent and delay the occurrence and progress of diabetic nephropathy through some mechanisms, which include improving glucolipid metabolism, improving insulin resistance, and some other nonhypoglycemic action mechanisms [6]. This evidence concerns the gene INS and type 2 diabetes mellitus.