Figure 8. Effects of Ast on cartilage degradation in vivo. Mice received intra-articular injections of Ast (20 mg/kg) or vehicle for 8 weeks after DMM surgery. (A) Histological analysis of cartilage degradation was evaluated by safranin O staining. Representative safranin O staining of cartilage (scale bar: 200 μm and 50 μm). (B) Osteoarthritis Research Society International (OARSI) scores of three groups. (C) Nrf2 expression in cartilage was detected by immunofluorescence staining (scale bar: 50 μm). (D) Dot plots graphs represent rates of nuclear Nrf2 in total chondrocytes from each cartilage section. The data are presented as dot plots from three independent experiments. Significant differences among different groups are indicated as **P < 0.01; ***P<0.001; ****P < 0.0001.