Protective effects of biochanin A on articular cartilage: in vitro and in vivo studies

Background Increased production of matrix metalloproteinases (MMPs) is closely related to the progression of osteoarthritis (OA). The present study was performed to investigate the potential value of biochanin A in inhibition of MMP expression in both rabbit chondrocytes and an animal model of OA. Methods MTT assay was performed to assess chondrocyte survival in monolayers. The mRNA and protein expression of MMPs (including MMP-1, MMP-3, and MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in interleukin-1 (IL-1β)-induced rabbit chondrocytes were determined by quantitative real-time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The involvement of the NF-kappaB (NF-κB) pathway activated by IL-1β was determined by western blotting. The in vivo effects of biochanin A were evaluated by intra-articular injection in an experimental OA rabbit model induced by anterior cruciate ligament transection (ACLT). Results Biochanin A downregulated the expression of MMPs and upregulated TIMP-1 at both the mRNA and protein levels in IL-1β-induced chondrocytes in a dose-dependent manner. In addition, IL-1β-induced activation of NF-κB was attenuated by biochanin A, as determined by western blotting. Moreover, biochanin A decreased cartilage degradation as determined by both morphological and histological analyses in vivo. Conclusions Taken together, these findings suggest that biochanin A may be a useful agent in the treatment and prevention of OA.