Effects of shuangtengbitong tincture on collagen-induced arthritis in rats

Shuangtengbitong tincture (STBT), a clinical prescription from the Fujian University of Traditional Chinese Medicine (TCM) Affiliated People's Hospital (Fuzhou, China), has been used in the treatment of rheumatoid arthritis (RA) for similar to 10 years. The aim of the current study was to confirm the anti-RA effect of STBT and to evaluate the potential mechanisms underlying collagen-induced arthritis (CIA) in rats. CIA model Wistar rats were induced with bovine type II collagen. The rats were immunized with CIA and were treated with STBT (0.5 and 2 ml/injection) and votalin (similar to 1 cm/injection) continuously for similar to 1 month. Following treatment, the pathological sections of CIA rat joints were observed by hematoxylin and eosin staining, expression of toll-like receptor-4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear transcription factor-kappa B (NF-kappa B) were investigated by western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Following treatment, STBT significantly suppressed paw swelling (P<0.05) compared with the model group and increased body weight. STBT also reversed pathological changes, STBT-treated rats showed a significant improvement of synovial hyperplasia, inflammatory infiltration, and cartilage and bone destruction. The levels of protein and mRNA expression of TLR4, MyD88 and NF-kappa B were markedly suppressed in the synovial tissue of STBT- and votalin-treated rats. In addition, STBT showed marked inhibition of the levels of protein and mRNA expression of TLR4, MyD88 and NF-kappa B at an STBT volume ranging between 1 and 4 ml/day, indicating that the inhibition was volume dependent. These results show that STBT inhibits CIA and may be correlated with TLR4, MyD88 and NF-kappa B expression.