For example, RAAS inhibitors inhibit the abnormal elevation of O-GlcNAcylation by increasing O-GlcNAc enzymes and improve Akt/eNOS phosphorylation by restoring the vascular function, upregulating HSP72 expression, and thereby slowing the progression of DKD [122] (Fig. 6). Here, NOS3 is linked to diabetic kidney disease.