Inhibitory effects of melittin on the production of lipopolysaccharide-induced matrix metalloproteinase 3 in human osteoarthritic chondrocytes.

In continuation of our previous study which explored the effect of bee venom (BV) on the global gene expression profiles in lipopolysaccharide (LPS)-treated human chondrosarcoma cells, we investigated herein the effect of melittin, a major component of BV, on the productions of matrix metalloproteinases (MMPs) 1, 3, and 13 in primary cultured human arthritic chondrocytes. Increased generations of MMPs 1, 3, and 13 were observed by MMPs stimulating agents LPS, tumor necrosis factor alpha (TNF-alpha), and interleukin 1beta (IL-1beta). The generations of LPS (1 microg/ml)-induced MMPs 1 and 13 were not decreased by melittin, whereas that of LPS-stimulated MMP 3 was significantly inhibited by melittin. IL-1beta (10ng/ml) and TNF-alpha (10ng/ml)-induced MMPs 1, 3 and 13, however, were not decreased by melittin. Immunoblot analysis revealed that melittin exerted no effect on the LPS-stimulated expression levels of MMPs 1 and 13 but attenuated the LPS-induced MMP 3, which is consistent with the enzyme-linked immunosorbent assay (ELISA) data. Taken together, these findings suggest melittin may exert its anti-arthritic effect, at least in part, by inhibiting LPS-stimulated MMP 3 production in human osteoarthritic chondrocytes.