Alchornea cordifolia (Euphorbiaceae) is a very prized plant among traditional healers in Africa. Its leaves are used for its antipyretic properties in traditional areas. The aim of our study is to determine the acute toxicity and the antipyretic activity of a methanolic extract of Alchornea cordifolia leaves. Acute toxicity was assessed by measuring mortality, changes in body weight, spontaneous movements, and normal rectal temperature in mice. Antipyretic activity was evaluated by brewer's yeast-induced hyperpyrexia in rats according to Teotino method (1963). The antipyretic effect of methanolicextract of Alchornea cordifolia leaves was compared with paracetamol (100 mg/kg bw) orally. Groups of mice treated with doses of 6500; 3250; 1625 and 812.5mg/kg of the extract did not show any mortality, nor significant alteration of body weight, nor alteration of spontaneous movements. However, incomplete reversed dose-dependent hypothermic activity was observed with doses of 50.78; 101.56; 203.12; 406.25; and 812.5 mg/kg p.o. of the extract, showing acute toxicity of this plant. In the antipyretic assay, the extract with doses of 50.78; 101.56; 203.12; 406.25; and 812.5 mg/kg p.o. exhibited a significant dose-dependent antipyretic activity similar to paracetamol (100 mg/kg bw) in rats. Thus Alchornea cordifolia may inhibit prostaglandins-biosynthesis from hypothalamus. Our results support claims on its traditional uses in management of fever. However Alchornea cordifolia may affect hypothalamus not only during fever but also when body temperature is normal.

RESUME L'écorce de racines de Dichrostachys cinerea (L.) Wight et Arn. (Fabaceae) est traditionnellement utilisée, par trituration aqueuse en instillations nasales, pour traiter l'asthme en Côte d'Ivoire. Des propriétés antispasmodiques sur la musculature lisse du tractus respiratoire d'une part, des propriétés antioxydante et analgésique d'autre part, d'un extrait hydro-éthanolique de cette partie de la plante, ont précédemment été mises en évidence. Les présentes investigations ont consisté en l'évaluation de paramètres cliniques, hématologiques et biochimiques au cours d'une étude de toxicité subaiguë des doses pharmacologiquement actives du même extrait de la drogue végétale. Les tests réalisés, par administration orale de l'extrait à 10, 100, et 1000 mg/kg pc chez des rats de souche Wistar, conformément aux lignes directrices de l'OCDE 407, n'ont pas mis en évidence d'effets toxiques significatifs ni sur les mensurations corporelles (température et poids), ni sur les éléments figurés du sang, ni sur les activités des transaminases ou sur les fonctions métaboliques glucidique et rénale. Ces résultats suggèrent que, dans l'usage antiasthmatique traditionnel de la crise d'asthme, l'extrait ne contient pas de substances mortelles sur 28 jours. Toutefois, des études de toxicité chronique seraient requises pour attester l'innocuité de l'écorce de racines de Dichrostachys cinerea dans un usage au long cours.

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Alchornea cordifolia is a medicinal plant, whose ethanolic and methanolic extracts have shown antioxidant activity which could confer hepatoprotective effect, knowing that liver cells are attacked by free radicals. The hepatoprotective effect of these extracts has been demonstrated in models of hepatotoxicity induced by paracetamol high doses in animals. However, anti-tubercular drugs at the usual dose present hepatotoxicity risk. Could Alchornea cordifolia help to limit hepatotoxicity induced by anti-tubercular drugs? This work aimed to evaluate the antioxidant activity and the hepatoprotective effect of an aqueous extract of A. cordifolia leaves (AEAC). The antioxidant activity of A. cordifolia leaves was studied in vitro by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals scavenging assay and by the iron reduction ability. A phytochemical screening was carried out to identify the chemical groups that could be responsible for this activity. The hepatoprotective effect was demonstrated in a model of hepatotoxicity induced by isoniazid and rifampicin in rats. Two hours after induction of hepatotoxicity, the animals were orally administered the AEAC at 200 mg/kg, 400 mg/kg, 800 mg/kg for 10 consecutive days. A blood sample was taken on the 11 th day for the evaluation of transaminases, markers of hepatic cytolysis. A totally of 96 rats were used in this study. AEAC showed dose-dependent antioxidant activity. Phytochemical screening revealed the presence of flavonoids, tannins and alkaloids. Administrated alone, aqueous extract of A. cordifolia leaves didn't modificate the transaminases, isoniazid and the isoniazid + rifampicin combination resulted in increasing transaminases (ALT and AST) by more than 48%. AEAC at 800 mg/kg reduced AST and ALT levels by more than 45%. AEAC at 200 mg/kg and 400 mg/kg decreased ALT more than 40%. Knowing that antioxidant activity protects liver, the AEAC may by its antioxidant activity, contribute to protect against the hepatotoxicity induced by an-