Effects of curcumin on expressions of TGF-β1, and the effect of TGF-β1 on cathepsins K and L expression. Representative immunohistochemical images and image analysis (A) of TGF-β1 expression in bleomycin treated mice (9- 10 mice per group). Curcumin significantly decreased TGF-β1 expressions at 14d and 28d. All data besides the TGF-β1 analysis (means ± SE) represent means of three independent experiments ± SD (* p < 0.05, all compared to bleomycin treated group only). (B) Representative immunoblot images and their quantitative analysis display the dose-dependent reduction of TGF-β1 protein content by curcumin in bleomycin treated HFL-1 cells. In contrast, LHVS increased TGF-β1 protein content two-fold (C). Panel D shows a 7 and 5-fold increase in the expressions of CatK and L in TGF-β1 treated HFL-1 cells when exposed to curcumin (20 μM) whereas TGF-β1 alone significantly decreased cathepsin expression. All data represent means of three independent experiments ± SD (* p < 0.05, all compared to bleomycin or TGF-β1 treated group only).