Figure 4. DHC reduced TNF-α- induced expression of MMP-1, MMP-3, and MMP-13. Cells were stimulated with TNF-α (10 ng/ml) in the presence or absence of 10 and 20 μM for 24 h. (A). mRNA of MMP-1, MMP-3, and MMP-13 as measured by real time PCR; (B). Protein of MMP-1, MMP-3, and MMP-13 as measured by ELISA (****, P<0.0001 vs. vehicle group; $$, $$$$, P<0.01, 0.0001 vs. TNF-α treatment group).