SMAD3 and Hepatic fibrosis: MiR-29a was reported to exert detrimental effect in promoting HSC activation and liver fibrosis via targeting Sirt1 [159], while another study demonstrated that overexpression of miR-34 in HSCs ameliorated the development and progression of liver fibrosis by targeting Smad4 and regulating TGF-β1/Smad3 pathway [160].