Studies in T2DM model mice (Miyagawa et al., 2013) have demonstrated that co-treatment with vildagliptin (a DPP4 inhibitor) and valsartan (an AT1R inhibitor) synergistically reduced blood glucose levels primarily through synergistically improving the insulin secretion of islets, as well as amelioration of fatty acid oxidation in the liver. Here, DPP4 is linked to type 2 diabetes mellitus.