Abstract:
The root of Clematis chinensis Osbeck has been used widely in rheumatoid arthritis in Chinese
traditional medicine, and AR-6 is a triterpene saponin isolated from it. In this present study, we
investigated the in vivo effects of oral AR-6 in chronic rat with collagen-induced arthritis (CIA)
and possible molecular mechanism. CIA was induced by immunizing 56 female Sprague-Dawley
(SD) rats with chicken typeIIcollagen (CII). Following eighteen days, the immunization rats with
CIA were treated with AR-6 (32, 16, 8 mg/kg), cyclophosphamide (7 mg/kg), and TGP (Total
Glucosides of Paeonia) (180 mg/kg) for 7 days, and rats without CIA were given the same
volume of purified water. TNF-α and IL-1β levels in peripheral blood will be measured by ELISA,
and Western blot analysis will be used to detect the expression of NF-κB p65 subunits, TNF-α
and COX-2, in synovial membrane. We found that therapeutic treatment with AR-6 markedly
improves the paw swelling and histopathological changes. Moreover, the serum levels of proinflammatory cytokines TNF-α and IL-1β were markedly lowered, and the expression of NF-κB
p65 subunits, TNF-α and COX-2, in the synovial membrane of CIA rats was significantly inhibited
in the AR-6-treated groups. These results enable to prove that AR-6 has a potential antiinflammatory effect in CIA rats, and its mechanism may relate to the inhibition of the
expression of NF-κB p65 subunits, TNF-α and COX-2
