Fullerene inhibited the decrease in cell proliferation ability of chondrocytes which is observed when cultured chondrocytes are treated with a cartilage degenerating factor (IL-1β or H2O2). Fullerene inhibited production of cartilage matrix-degrading enzymes (matrix metalloprotease (MMP)-1, 3 and 13) which is induced in cultured chondrocytes by cartilage degenerating factors. Fullerene restored the decrease in cartilage matrix (proteoglycan) synthesizing ability which is observed in treating cultured chondrocytes with cartilage degenerating factors. In an analysis using an osteoarthritis rabbit model, the progress of cartilage degeneration was reduced by administering fullerene. Moreover, the dynamic friction coefficient was decreased by adding fullerene to synovial fluid.
