DPP4 and diabetic kidney disease: Currently, a number of potential drugs showed beneficial effects in mouse model of DKD such as dipeptidyl peptidase 4 (DPP4) inhibitor, sodium-glucose cotransporter-2 inhibitors, glycolysis inhibitors, mineralocorticoid antagonists, inhibitors of renin-angiotensin system and peptide AcSDKP [2–10].