Effects of astragalosides on TGF-β1/Smad signaling pathway. The expressions of TGF-β1, TβR-I, p-Smad 2, Smad 2, p-Smad 3, Smad 3, and Smad 7 proteins were analyzed by western blot; Smad 2, Smad 3, and β-actin served as corresponding control. AST was found to attenuate the expression of TGF-β1, TβR-I, p-Smad 2, and p-Smad 3 proteins and enhance the expression of Smad 7, with no influence on the levels of Smad 2 and Smad 3 proteins. AST: astragalosides; LY-364947: TGF-β receptor 1 inhibitor. The values presented are the means ± SD (n = 10 in each group). P < 0.05 and ∗∗P < 0.01 versus control group; #P < 0.05 and ##P < 0.01 versus model group (CCL4).