Abstract
BACKGROUND Cartilage degeneration during osteoarthritis (OA) most adversely affects the quality of life by hindering the movement. The present study investigated the role of verbascoside in the protection of cartilage degeneration induced by osteoarthritis. MATERIAL AND METHODS The enzyme-linked immunosorbent (ELISA) and western blot assays were used for determination of inflammatory cytokine secretion in serum and cartilage tissues, respectively. RESULTS Treatment of the OA rats with verbascoside inhibited overproduction of interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and IL-1ß in serum as well as cartilage tissues. The expression of P2X7R and matrix metalloproteinase (MMP)-13 was much higher in the rats induced with OA. However, administration of verbascoside reversed the OA-induced upregulation of P2X7R and MMP-13 expression in the cartilage tissues. The OA-mediated increase in substance P (SP) and prostaglandin E2 (PGE2) expression was also reduced in the cartilage tissues by the verbascoside treatment. Western blot assay revealed that verbascoside treatment markedly decreased the activation of IkappaBalpha and NF-kappaB p65 in the OA rats. CONCLUSIONS Thus, verbascoside inhibited inflammatory cytokine secretion in the OA rats by targeting P2X7R expression, production of matrix metalloproteinase, PGE2 and downregulation of NF-kappaB signaling pathway. Therefore, verbascoside may be used as potent agent for osteoarthritis treatment.