TGFB1 and cholestasis: In cholestasis liver fibrosis models, SIRT1 inhibits the Transforming Growth Factor Beta 1 (TGF-β1)/Smad pathway, reducing profibrotic markers such as TGF-β, alpha-smooth muscle actin (α-SMA), and collagen I, thereby decreasing HSC activation and epithelial-mesenchymal transition, slowing fibrosis progression (Pan et al., 2022; Abd El Motteleb et al., 2017).