SMAD3 and Ureteral obstruction: Overexpression of SIRT1 suppressesTGF-β1-induced cellular apoptosis and fibrosis, and reducesCTGF expression by stimulating TGF-β1 in the kidneys ofmice with unilateral ureteral obstruction (Ren et al., 2015).SIRT1 is also able to weaken TGF-β-dependent signaling bydeacetylating SMAD3 and SMAD4 molecules, which inhibitsthe production of collagen, fibronectin, and MMP7 metalloprotease(Zhang Y. et al., 2017).