Abstract
We investigated the protective effect of hyaluronic acid (HA) on the matrix of cultured chondrocytes. The cultured chondrocytes were exposed to pathological synovial fluid from patients with rheumatoid arthritis (RA) and with osteoarthritis (OA), and to interleukin-1β (IL-1β), tumour necrosis factor α (TNFα), or oxygen-derived free radicals (ODFR) in the presence or absence of HA. The effects were evaluated by the preservation of labelled 35Sproteoglycan (PG) and the release of 35S into culture medium. IL-1β and TNF α concentrations in the pathological synovial fluid were determined by double antibody technique with RIA systems.
The addition of the pathological synovial fluid to culture medium, especially RA synovial fluid, significantly enhanced 35S release from the matrix. Adding IL-1β, TNFα, or ODFR was also found to promote 35S release. But no correlation was observed between the 35S release by the pathological synovial fluid and the concentrations of IL-1β and TNF α in the same synovial fluid. On the other hand, the addition of HA together with pathological synovial fluid, IL-1β, TNFα, or ODFR preserved 35S-PG in the matrix and restrained 35S release into culture medium. These results indicated that HA could be effective in protecting the degradative effect of pathological synovial fluid, IL-1β, TNFα, and ODFR on the matrix of cultured chondrocytes and may suppress the destructive process in cartilage tissue.
