Chondroprotective evaluation and docking study of two natural coumarins: murrangatin and murracarpin

Objective: To evaluate the chondroprotective activity of murrangatin and murracarpin from the leaves of Murraya exotica. Methods: Column chromatography was employed to separate the compounds; IL-1beta, TNF and #945;, PGE2, and MMP-13 were determined by ELISA; the docking with COX-2 was investigated by AutoDock 4.2 software. Results: Murrangatin and murracarpin both significantly down-regulated the expressions of IL-1beta, TNF and #945;, PGE2 in the rat osteoarthritis (OA) serum and PGE2 and MMP-13 in the OA chandrocytes cultured solution. The docking results showed that they shared a similar binding conformation with that of Indomethacin. Murrangatin and murracarpin both had lower affinity with COX-2, probably due to lack of carboxyl group coordinating to Arg120. Conclusions: Both murrangatin and murracarpin show chondroprotective activity by downregulation of IL-1beta, TNF and #945;, PGE2, and MMP-13, and both of them might be a new backbone for developing inhibitors of COX-2. [J Intercult Ethnopharmacol 2013; 2(2.000): 91-98