Figure 5.

The detrimental effect of iron in OA pathogenesis. (A,B) Chondrocytes were treated with various concentrations of FAC and annexin V-FITC/PI flow cytometric analysis was conducted to evaluate apoptosis rate induced by FAC. (C) Chondrocytes were treated with various concentrations of FAC and MMP3, MMP13 proteins expression were determined by western blot analysis. (D) The band density of MMP3 and MMP13 were quantified and normalized to control. (E) Chondrocytes were treated with various concentrations of FAC and SOX9, COL2 proteins expression were determined by western blot analysis. (F) The band density of SOX9, COL2 were quantified and normalized to control. (G,H) Chondrocytes were treated with 10 ng/ml IL-1β with or without 100 μM DFO for 24 h and matrix degrading protein (MMP3, MMP13) expression were detected by western blot analysis. Data are presented as mean ± SD. All experiments were repeated three times independently. *P < 0.05; **P < 0.01; ***P < 0.001.