(Z)-5-(4-methoxybenzylidene) thiazolidine-2, 4-dione ameliorates the adjuvant-induced arthritis via inhibiting the migration of macrophage and down-regulating the cytokine mRNA expression

In our previous study, we have demonstrated that (Z)-5-(4-methoxybenzylidene) thiazolidine-2, 4-dione (SKLB010), a novel analogue of thiazolidinediones, showed protection against concanavalin A (Con A)-induced hepatitis via inhibiting the migration of macrophages and the expression of pro-inflammatory mediators. In present study, Transwell assay was applied to study the effects of SKLB010 on macrophage-like Raw264.7 cell migration and we investigated the effects of SKLB010 on NO generation in vitro. We also studied in vivo effects of SKLB010 on adjuvant-induced arthritis in Lewis rats by oral administration. It was proved that SKLB010 depressed cells migration and the production of NO in Raw264.7 cells in a dose-dependent way. Our results also indicated that oral administration of 50 mg/kg SKLB010 markedly resulted in a clear suppression of clinical signs compared to untreated groups, showing as markedly reduction of paw swelling and inhibition of body weight decreasing. The improvement in disease severity was accompanied by suppression of CD68-positive cells in knee joint and by inhibition of production in pro-inflammatory cytokines of TNF-α, IL-1β and IL-6 in serum. The elevated TNF-α, IL-1β and iNOS mRNA expression in tissue were down-regulated after treatment with SKLB010. SKLB010 also significantly inhibited the histological progress of RA. These data indicate that SKLB010 is a potent anti-inflammatory therapeutic agent targeting the inflammatory response of macrophages.

Research Highlights
► SKLB010 inhibits the migration of macrophages.
► Treatment of rheumatoid arthritis partly depends on the inhibition of macrophage migration.
► SKLB010 decreases the expression of inflammation mediators (TNF-α, ILβ, IL-6 and iNOS).