The inhibitory effect of DSF/Cu on TGF-β1 activated 3T3 cells was more obvious than that of normal 3T3 cells. (A) α-SMA protein was detected by Western blot in 3T3 cells. TGF-β1 (20 ng/mL) was incubated for 48 h. Data are shown as means ± SD. * p < 0.05, *** p < 0.001, n = 3. (B) 3T3 cells were exposed to DSF/Cu (1 μM/1 μM) for different lengths of time, after which, inhibition effects were determined by MTT assay. TGF-β1 (20 ng/mL) was pretreated for 48 h. Data are shown as means ± SD. * p < 0.05, *** p < 0.001, n = 3. (C) Representative images of 3T3 treated with DSF/Cu (1 μM/1 μM) for 24 h. TGF-β1 (20ng/mL) was pretreated for 48 h. Scale bar: 200 μM. (D) The expression of α-SMA was detected by Western blotting in 3T3 after incubation with DSF/Cu for 12 h. TGF-β1 (20 ng/mL) was pretreated for 48 h. Data are shown as means ± SD. *** p < 0.001, n = 3.