DPP4 and type 2 diabetes mellitus: Recent data suggested that AGEs significantly increased DPP-4 expression and sDPP-4 release by tubular cells, whereas AGE and RAGE expression levels are reduced in the kidney of DPP-4-deficient diabetic rats, suggesting the existence of a cross-talk between the AGE–RAGE axis and DPP-4 in the pathogenesis and progression of T2D [56,57].