Résumé
Aim: Phyllanthus amarus Schum (Euphorbiaceae) is an annual herbal shrub which has been used in traditional medicine in Nigeria to treat some disease conditions. The aim of this study is to evaluate the anti-inflammatory and analgesic activities of the aqueous extract of Phyllanthus amarus in experimental animal models hence confirming its folkloric use. Study Design: Forty healthy white Wister strain albino rats (100–200g) and forty mice (15–30g) of either sex bred in the experimental animal house of the Faculty of Veterinary Medicine, University of Ibadan, Nigeria were used for the study. Forty rats were used for anti-inflammatory study while forty mice used for the analgesic study. In anti-inflammatory study, carrageenan and histamine-induced paw oedema were used while acetic acidinduced writhing test and formalin-induced paw lick test were deployed for analgesic test. Place and Duration of Study: Faculty of Veterinary Medicine, University of Ibadan, Nigeria; 2 months. Methodology: Soft drink extract (SDE) was prepared by dissolving ground plant materials (200g) in 1 L seven up (7 UP®) for 48 h, filtered, lyophilized and then used for the pharmacological investigations. Standard phytochemical methods were used to test for the presence of phytoactive compounds in the plant. Acute toxicity was carried out in mice to determine safe doses for use. The anti-inflammatory activities were conducted using carrageenan and histamine to induce oedema in rats while analgesic activities were embarked upon using acetic acid- induced writhing test and formalin-induced paw lick test. Results: The extract in doses of 100 and 200 mg/kg at 3 hr showed 15.1 and 16.4% inhibition of histamine induced-paw oedema respectively while ibuprofen caused 9.6% inhibition at the same period. In the case of carrageenan induced paw oedema, the extract in doses of 100 and 200 mg/kg at 4 hr showed 10.5 and 12.0% inhibition respectively while ibuprofen only caused 3% inhibition. In the acetic acid- induced writhing test, the extract showed a good analgesic activity characterized by a significant reduction in the number of writhes with 100 and 200 mg/kg doses used when compared to the control group. The result was also similar to the formalin-induced paw lick test. Conclusion: The soft drink leaf extract of Phyllanthus amarus has both analgesic and anti-inflammatory potential. The activities of this extract were comparable to that of ibuprofen, the reference drug used in this study.
Résumé
Margaritaria discoidea is a medicinal plant used for the treatment of various body pains in Central, Eastern and Southern Africa. The aqueous extract of its stem bark was investigated for its anti-inflammatory and analgesic activities in animal models. The extract at 50, 100 and 200mg/kg body weight reduced significantly the formation of oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract had a good analgesic effect characterized by a reduction in the number of writhes when compared to the control. Similarly, the extract caused dose-dependent decrease of licking time and licking frequency in rats injected with 2.5% formalin. These results were also comparable to those of indomethacin, the reference drug used in this study. Acute toxicity test showed that the plant may be safe for pharmacological uses. This study has provided some justification for the folkloric use of the plant in several communities for conditions such as stomachache, pain and inflammations. Rev. Biol. Trop. 57 (4): 1193-1200. Epub 2009 December 01.
Margaritaria discoidea es una planta medicinal usada para el tratamiento de varios dolores corporales en la parte sur, central y oriental de África. Se investigaron las propiedades analgésicas y antiinflamatorias de la extracción acuosa de la corteza de su tallo en modelos animales. Los extractos de 50, 100 y 200mg/kg de peso corporal redujeron significativamente la formación del edema inducido por la carragenina y la histamina. En el modelo de contracción abdominal inducida por ácido acético, el extracto mostró un buen efecto analgésico caracterizado por la reducción en el número de contracciones en comparación con el grupo control. El extracto causó una disminución dependiente de la dosis del tiempo y la frecuencia de lamido en las ratas inyectadas con formalina al 2.5%, lo cual evidencia su efecto analgésico. Estos resultados fueron comparables con los de la indometacina, la droga de referencia usada en este estudio. La prueba de toxicidad aguda mostró que la planta podría ser segura para usos farmacológicos. Este estudio proporciona justificación para el uso folclórico de esta plata en varias comunidades, con el objetivo de tratar padecimientos tales como dolor de estómago, dolor e inflamaciones.