MMP1 and osteoarthritis: In order to test the therapeutic effects of SA on osteoarthritis, we examined the OA-related gene expression in chondrocytes pretreated with IL-1β for 24 hours (Figure 3) and found that SA decreased IL-1β-induced expressions of MMP-1, MMP-3, MMP-13, ADAMTS4, and ADAMTS5 in primary mouse chondrocytes in a dose-dependent fashion.