Angiotensin‐converting enzyme inhibitors can effectively protect against renal fibrosis and reduce the incidence of CKD by inhibiting DPP‐4, phosphorylation of Smad3 and increasing miR‐29s expression in the kidneys of DM‐induced mice and in human endothelial cells.204, 205. The gene discussed is SMAD3; the disease is renal fibrosis.