The protective effect of xanthan gum on interleukin-1β induced rabbit chondrocytes.

We have previously shown that intra-articular injection of xanthan gum (XG) could protect the joint cartilage and reduce osteoarthritis progression. In this study, we investigated the preliminary cytotoxicity of XG on chondrocytes, evaluated the effects of XG on the proliferation and the protein expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinase-1 (TIMP-1) in interleukin-1β (IL-1β)-induced rabbit chondrocytes. Primary rabbit chondrocytes were cultured. After treatment with various concentrations of XG with or without 10 ng/mL IL-1β, the proliferation of chondrocytes was evaluated using the MTT assay and the expression levels of MMPs and TIMP-1 were evaluated using ELISA. The results showed that XG alone displayed no adverse effects on cell viability and reversed significantly IL-1β-reduced cell proliferation in a dose-dependent manner. Furthermore, XG showed a dose-dependent inhibition in the IL-1β-induced release of MMPs while increasing TIMP-1 expression. These results strongly suggest that XG affords protection on IL-1β induced rabbit chondrocytes.