Figure 5.

Curcumin administration inhibited the transforming growth factor (TGF)-β1-induced activation of Smad2 in cardiac fibroblasts (CFs). CFs were pretreated with 20 µmol/l curcumin, 10 µM SB431542 (Smad2 inhibitor) or 10 µM SB203580 (p38 inhibitor) for 30 min, followed by treatment with 10 ng/ml TGF-β1 for 30 min. Densitometric analysis was performed to quantify the phosphorylation levels, which are presented as the ratio between the optical densities of the p-Smad2 and total Smad2 bands. *P<0.05 vs. the control group; ^#P<0.05 vs. the TGF-β1 group.