Inhibitory effect of TRK-530 on inflammatory cytokines in bone marrow of rats with adjuvant arthritis

TRK-530 is a novel synthetic bisphosphonate compound which exhibits inhibitory activity in the rat Adjuvant arthritis (AA) model. We found that, during AA development, the concentrations of cytokine-induced neutrophil chemoattractant-1 (CINC-1) and tumor necrosis factor alpha (TNF-alpha) in the bone marrow increased, and that administration of TRK-530 decreased the concentrations of these cytokines. The suppression of these concentration increases paralleled the inhibition of paw edema. Paw edema inhibition by TRK-530 in rat AA may be the result of decreasing CINC-1 and TNF-alpha concentrations.