FIGURE 4.

Vorinostat prevented IL‐1α‐induced degradation of type Ⅱ collagen and the expression of MMP‐13 in human T/C‐28a2 cells. Cells were stimulated with 5 ng/ml IL‐1α in the presence or absence of vorinostat (100 and 200 nM) for 24 h. (A) Levels of type Ⅱ collagen were measured by western blot analysis. (B) mRNA of MMP‐13. (C) Protein of MMP‐13 as measured by ELISA (N = 5, ****p < 0.001 vs. the vehicle group; **p < 0.05, ***p < 0.01 vs. the IL‐1α group). ELISA, enzyme‐linked immunosorbent assay; IL, interleukin; MMP‐13, matrix metalloproteinase 13; mRNA, messenger RNA