Fig. 3.

ACT promotes cell proliferation and inhibits cell apoptosis in primary chondrocyte stimulated by IL-1β. Rat primary chondrocytes were untreated or treated with 10 ng/mL IL-1β together with different concentration of ACT ACE (positive control, 30 μM) for 24 h. a MTT assay was performed to examine chondrocyte viability. b chondrocyte proliferation was measured by colony formation assay. c Annexin V/PI staining was performed to examine the chondrocyte apoptosis. d The protein expression of Bcl-2, Bax, and Cleaved-caspase 3 were analyzed. *** p < 0.001, ** p < 0.01 and * p < 0.05 compared with blank group. ## p < 0.01 and # p < 0.05 compared with IL-1β group. The experiment was repeated three times and the representative results were shown