Anti-Arthritic Activity of the Methanolic Leaf Extract of Urtica pilulifera L. on Albino Rats

Problem statement: Urtica pilulifera (Urticeacae) has been used in folk medicine to alleviate inflammation and arthritis. In this study the anti-arthritic effect of methanolic leaf extract of the plant was evaluated and compared to untreated control as well as ibuprofen-treated groups in a rat model of Complete Freund's Adjuvant (CFA)-induced arthritis. Approach: Arthritis was induced by injecting CFA subcutaneously into the right paw. The extract was given orally one day before CFA injection up to the completion of study (for 30 days). Two extract doses (1.33 and 2.0 g kg^-1) and ibuprofen (53 mg kg^-1) as a positive control were used. Paw volume was measured on alternate days up to 30 days. In addition, the effect of the extract on joint deformity, ankle swelling and inflammatory markers was evaluated. Results: The extract prevented arthritis-induced increase in paw volume and joint deformity dose-dependently as compared to control. Moreover, the extract showed significant increase in the packed cell volume [p<0.05]. No alteration of kidney or liver function tests was detected in rats during repeated dose treatment. Conclusion: This study supports the traditional use of U. pilulifera for the treatment of inflammatory disorders and rheumatoid arthritis and suggests further evaluation for its role in increasing red blood cells.