Therapeutic effects of total steroid saponin extracts from the rhizome of Dioscorea zingiberensis C.H.Wright in Freund's complete adjuvant induced arthritis in rats

The aim of our present study is to explore the anti-arthritic potential effect of total steroid saponins (TSSNs) extracted from the rhizome of Dioscorea zingiberensis C.H.Wright (DZW) and to investigate the underlying mechanisms. This work was performed using adjuvant-induced arthritis (AIA) rats in vivo and lipopolysaccharide (LPS) simulated 264.7 macrophage cells in vitro. In AIA-induced arthritic rats, TSSN significantly alleviated the arthritic progression through evaluating arthritic score, immune organ indexes, paw swelling, and body weight. This phenomenon was well correlated with significant suppression of the overproduction of inflammation cytokines (IL-1, IL-1β, IL-6, and TNF-α), oxidant stress makers (MDA and NO), eicosanoids (LTB4 and PGE2), and inflammatory enzymes (5-LOX and COX-2) versus the AIA rats without treatment. On the contrary, the release of SOD and IL-10 was profoundly increased. What's more, TSSN could obviously ameliorate the translocation of NF-κB to the nucleus through phosphorylation of the p65 and IκBα in vivo and in vitro. The current findings demonstrated that TSSN could protect the injured ankle joint from further deterioration and exert its satisfactory anti-arthritis properties through anti-inflammatory and anti-oxidant effects via inactivating the NF-κB signal pathway. This research implies that DZW may be a useful therapeutic agent for the treatment of human arthritis.