Evaluation of Moringa oleifera Aqueous Extract for Antinociceptive and Anti-Inflammatory Activities in Animal Models

Moringa oleifera L. (Moringaceae) is known to possess high nutritional value and is used in a folklore medicine to treat various ailments related to pain and inflammation. The aim of the present study was to evaluate the antinociceptive and anti-inflammatory effects of the aqueous extract of the leaves of M. oleifera in laboratory animals, using the writhing, hot-plate and formalin tests as the antinociceptive assays, and carrageenan-induced paw edema test as the anti-inflammatory assay. The extract (10, 30 and 100 mg/kg) exhibited significant (P < 0.05) antinociceptive activity, which occurred in a dose-dependent manner, in all tests used. The extract also exhibited significant (P < 0.05) anti-inflammatory activity in a dose-dependent manner. Furthermore, the extract antinociceptive activity was suggested to be modulated via opioid receptors at the central, but not peripheral, antinociceptive level, based on the ability of 5 mg/kg naloxone to reverse the extract activity in the hot-plate, but not the writhing test. In conclusion, M. oleifera leaves possess peripherally non-opioid mediated and centrally opioid mediated antinociceptive and anti-inflammatory activities. This study also confirms the traditional uses of M. oleifera in the treatment of ailments, particularly those related to pain and inflammation.