Protective effect of Traditional Chinese medicine Shuangwu Zhentong Capsule on collagen-induced arthritis in rats and possible mechanisms

The aim of this study was to investigate the protective effect of Traditional Chinese medicine Shuangwu Zhentong Capsule (SZC) on collagen-induced arthritis (CIA) and the possible mechanisms. Sixty rats were randomly divided into control and model: low-, medium-, and high-dose SZC and prednisone acetate (PA) groups, with 10 rats in each group. The CIA model was established in later 5 groups. The rats in low-, medium-, and high-dose SZC groups were intragastricallly administered with SZC, with dose of 0.5, 1, and 2 g/kg, respectively. The PA group was intragastricallly administered with 5 mg/kg PA. The treatment was performed for 3 weeks. Before treatment and after treatment, the paw swelling degree and polyarthritis index score of rats were measured. At the end of experiment, the serum tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and nitric oxide (NO) levels were determined. The expressions of Ras and Raf-1 protein in synovial tissue were detected. Results showed that, after treatment, compared with model group, in high-dose SZC and PA groups, the paw swelling degree, polyarthritis index score, serum TNF-α, IL-1β and NO levels, and synovial tissue Ras and Raf-1 protein levels were significantly decreased, respectively ( P  < 0.05). In conclusion, SZC has obvious protective effects on CIA in rats. The mechanisms may be related to its resistance of inflammatory reaction and down-regulation of Ras and Raf-l protein expressions in synovial tissue.