SMAD3 and diabetic kidney disease: In studies of other Sirtuin family members with DKD models, SIRT2 can deacetylate Forkhead Box Protein O3a (FoxO3a) (96), SIRT3 can deacetylate isocitrate dehydrogenase 2 (IDH2) (100), and SIRT6 can deacetylate Smad3 (111).