Amelioration of oxidative stress in the joint tissue may be the basis for the antiarthritic activity of Terminalia arjuna bark extract

Aim: In this study we have evaluated the antioxidant and antiarthritic activity of Terminalia arjuna bark extract (TABE) in collagen-induced arthritis (CIA) in rats.

Methods: Arthritis was induced in rats by intradermal injection of the collagen-complete Freund's adjuvant emulsion. Right hind paw thickness was measured as a primary marker for severity of arthritis. Biochemical parameters such as tissue levels of superoxide dismutase (SOD), catalase, reduced glutathione (GSH), nitrites and thiobarbituric acid reactive substances (TBARS) were measured to determine the effect of treatment on antioxidant defenses. Articular elastase (ELA) level in the arthritic tissue was measured as a marker for neutrophil infiltration.

Result: Terminalia arjuna bark extract administration significantly inhibited the increase in paw thickness induced by immunization with collagen as compared to CIA-control animals. Further, it attenuated the fall in tissue SOD and GSH levels and mitigated the increase in tissue nitrites and TBARS levels as compared to CIA-control animals. Tissue ELA levels, which were significantly increased in the CIA-control animals as compared to normal animals were also significantly reduced by TABE administration.

Conclusion: Results of our study demonstrate the antioxidant and antiarthritic activity of TABE in CIA in rats. We believe that TABE could find clinical application in the management of rheumatoid arthritis and associated disorders.