In conclusion, DPP-4 inhibition attenuated MCT-induced renal fibrosis by reducing renal cell apoptosis via increasing the protein expression of survival factor GRP78, inhibiting the phenotypic conversion of renal microvascular SMCs, and inhibiting EndMT via upregulating BMPR2 and downregulating TGF-β1. The gene discussed is HSPA5; the disease is renal fibrosis.