[Effect of a Harpagophytum procumbens DC extract on matrix metalloproteinases in human chondrocytes in vitro].

Inflammatory articular cartilage diseases such as arthritis and osteoarthritis are characterized by a loss of articular cartilage due to an imbalance between synthesis and degradation of the extracellular cartilage matrix. These diseases are accompanied by an increased induction of cytokines such as interleukin 1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha). The increased release of cytokines leads to an enhanced production of matrix-degrading enzymes e.g. the matrix metalloproteinases (MMPs). In this study the direct antirheumatic effects of an extract of the secondary root of the African devil's claw (Harpagophytum procumbens DC) on the production of MMPs in IL-1beta-stimulated human chondrocytes were examined. A detailed evaluation by immunomorphological methods and Western blot analysis showed that the extracts of Harpagophytum decreased significantly the production of MMPs (MMP-1, MMP-3, MMP-9) in chondrocytes. The IL-1beta-induced production of MMPs was also significantly reduced by both a JM-extract (Jucurba) containing 210 mg dry extract and JF-extract (Jucurba forte) containing 480 mg dry extract. After all it could be shown that the effect of JF-extract on the MMP-synthesis was more pronounced in untreated and cytokine-stimulated chondrocytes when compared with the effect of the JM-extract. The capability of the JM-extract to suppress the MMP-production via the inhibition of the synthesis of inflammatory cytokines could explain its therapeutic effect in arthritic inflammations. In these in vitro experiments the JF-extract showed a higher efficacy than the JM-extract.