Even though apelin was reported to increase albuminuria in diabetic mice through increasing renal blood flow23 and inhibiting autophagy of pdocytes24, the present study demonstrated that EMT of podocytes in mice with DKD is suppressed by apelin, which was mediated by decreasing the transcription of TGFβ through inhibiting the expression of proteasome subunit β5i. This evidence concerns the gene PSMB8 and diabetic kidney disease.