In vitro effects of hyaluronan on prostaglandin E2 induction by interleukin-1 in rabbit articular chondrocytes

Effects of hyaluronan (HA) on the prostaglandin E2 (PGE2) production induced by recombinant human interleukin-1 beta (rhIL-1 beta) in rabbit articular chondrocytes were studied in vitro. The rhIL-1 beta-induced PGE2 production was dose-dependently inhibited by HA. HA with the highest molecular weight (M(r) = 2.0 x 10(6)) exhibited an inhibitory effect that was statistically more significant than the same polymer of lower molecular weights (M(r) = 1.0 x 10(6), 0.5 x 10(6)). This effect was observed in both young and adult rabbit articular chondrocytes. Since PGE2 has been implicated as a mediator of inflammatory joint diseases, our observations suggest that HA may elicit an anti-inflammatory effect by inhibiting PGE2 production.