Figure 6. RIPK1 kinase-mediated osteoarthritis is dependent on apoptosis but not mixed lineage kinase domain-like pseudokinase (MLKL)-dependent necroptosis. (A, B) Western blots and quantitative data of p-MLKL. (C, D) Immunohistochemical staining of p-MLKL in the normal and DMM groups (n = 10); scale bar = 200 μm. (E, F) Western blots and quantitative data of MMPs. (G, H) Cleaved caspase 3 and cleaved poly (ADP-ribose) polymerase (PARP) levels in mouse chondrocytes treated as above. The experiments were repeated three times independently. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.