Evaluation of the combination of Uvaria chamae (P. Beauv.) and amodiaquine in murine malaria.

Ethnopharmacological relevance: The leaf and fruit of Uvaria chamae P. Beauv (Annonaceae) are used in antimalarial ethnomedical preparations. Therefore, they were investigated for antimalarial activities as well as possible herb-drug interaction with amodiaquine (AQ).Materials and methods: The methanol extracts of the leaf (UCL) and fruit (UCF) were administered orally at 100-800 mg/kg/day in mice infected with chloroquine (CQ)-sensitive Plasmodium berghei NK65 using the four-day, curative and prophylactic antimalarial test models. The UCL was further evaluated at 100-800 mg/kg as twice-daily doses and combinations of UCL+AQ using the four-day test. Mice infected with CQ-resistant P. berghei ANKA were treated with UCL at 400 mg/kg and AQ at 10 mg/kg [UCL400+AQ10] mg/kg in the four-day and curative test models.Result: At 800 mg/kg/day, UCL, UCF gave chemosuppression of 42, 28% (four-day test), parasite clearance of 36.3, 49.5% on day 5 (curative test) and 64.3, 82.6% (prophylactic test), respectively. The twice-daily dose of UCL at 800 mg/kg showed activity of 51.50% while the combination of [UCL200-FAQ5] mg/kg exhibited chemosuppression of 91.66%, which was not significantly different (p > 0.05) from AQ at 10 mg/kg (85.41%). In the CQ-resistant P. berghei experiment, the combination gave a chemosuppression of 45.80%, significantly lower (p < 0.05) than AQ (78.40%) while the parasite clearance was not significantly different from AQ (curative test).Conclusion: The leaf extract showed moderate chemosuppressive activity. The lower-dose combination of the leaf extract and amodiaquine had better antimalarial activity in CQ-sensitive murine malaria. However, the tested combination had no beneficial antimalarial effect in CQ-resistant murine malaria. (C) 2016 Elsevier Ireland Ltd. All rights reserved.