Abstract

Eric Woode , George K. Ainooson , Eric Boakye-Gyasi , Charles Ansah1 , David D. Obiri , George A Koffour , Abraham Mensah and Mahama Duwiejua

Newbouldia laevis (fam. Bignoniaceae) is used in traditional medicine for the treatment of various conditions. The stem bark is used for pain, ulcer, arthritis, rheumatism and other inflammatory conditions. The purpose of this study is to pharmacologically validate the use of N. laevis stem bark extracts in African traditional medicine for the management of inflammatory conditions such as arthritis. Ethanolic stem-bark extract of N. laevis (10 - 100 mg kg-1 ) exhibited anti-arthritic activity by inhibiting the polyarthritic phase edema by 25.30 ± 2.53 - 28.11 ± 2.02 % with no significant inhibition of the acute phase response of the rat adjuvant-induced arthritis. Phenols were detected in the total ethanolic extract. Though both the extract and ?-tocopherol produced a concentration-dependent increase in reducing power properties, the extract (EC50 2.8 ± 1.59) was six-fold more potent than ?-tocopherol (EC50 18.18 ± 4.29). In contrast the ability of the extract to de-colorize DPPH free radical solution (EC50 39.86 ± 3.33 X 10-2 ) and inhibit lipid peroxidation in rat brain homogenate (IC50 1499.00 ± 408. 22 X 10-3 ) was less than ?-tocopherol and n-propyl gallate. Overall, our results indicate that N. leavis has anti-arthritic and antioxidant properties.