Anti-plasmodial and immunomodulatory activity of medicinal plants used in Burkina Faso to treat malaria

Plasmodium falciparum malaria is the most common cause of death in Burkina Faso. The persistence of drug resistance makes the disease difficult to control. The reliability of indigenous herbal drugs may be helpful. In Burkina Faso, the decoctions of Canthium henriquesianum Schum, Gardenia sokotensis Hutch. and Vernonia colorata Willd. are used to treat malaria. The study objective was to evaluate the antiplasmodial properties of these plant extracts and to check the relevance of their use. Decoctions of aerial parts were prepared and screened for antiplasmodial activity against both chloroquine-sensitive (D10) and resistant (W2) strains of P. falciparum. The aqueous extract from C. henriquesianum was the most active with IC50 of 103±44.2 and 66.8±21.6 μg/ml on D10 and W2, respectively. The ethyl acetate extract was even more potent with IC50 24.0±7.4 μg/ml. No toxicity was observed against mammalian cells, suggesting a good therapeutic index. The decoction of C. henriquesianum contains hydrolysable tannins and no alkaloids. Extracts of C. henriquesianum also inhibited the production of IL-1β, but not of TNFα, by human monocytes, thus confirming its traditional use as antipyretic. Attempts to identify the active principle for antiplasmodial and anti-inflammatory activities are ongoing. Financial support by EU18834AntiMal is acknowledged