Febuxostat mitigates IL-18-induced inflammatory response and reduction of extracellular matrix gene.

Background Osteoarthritis (OA) is a disease commonly diagnosed in the elderly population. It is reported that the reduction of extracellular matrix and infiltrated inflammation are two main factors responsible for the pathogenesis of OA. This investigation aims to explore the potential protective effects of Febuxostat against IL-18-induced insults in chondrocytes, as well as the possible mechanism. Materials and methods The viability of chondrocytes was evaluated using the MTT assay. QRT-PCR and ELISA were used to measure the expressions and concentrations of IL-6, TNF-α, and CCL5, respectively. The accumulation of glycosaminoglycans (GAGs) was measured using Alcian blue assay. The chondrocytes were transfected with siRNA against Sox-9 in order to establish the Sox-9 knock-down chondrocytes. The expressions of iNOS, Col2a1, Acan, and Sox-9 were measured using qRT-PCR. The production of NO was measured using Diaminofluorescein-FM diacetate (DAF-FM DA) staining. Results The up-regulated expressions of IL-6, TNF-α, CCL5, iNOS, and NO stimulated by IL-18 were down-regulated by the introduction of Febuxostat. The expressions of Col2a1, Acan, and Sox-9 were significantly reduced by IL-18 but greatly promoted by Febuxostat. The increased gene expressions of Col2a1 and Acan induced by Febuxostat were abolished by knocking down Sox-9 in the chondrocytes. Conclusion Febuxostat might mitigate IL-18-induced inflammatory response and reduction of the extracellular matrix gene mediated by Sox-9.