Therapeutic Efficacy of Triple Regimen of Artemether, Lumefantrine and Hippocratea africana in the Treatment of Plasmodium berghei Infected Mice

Abstract

Combination therapy is fast replacing monotherapy in the treatment of infectious diseases and Plasmodium resistance to artemisinin–based combination therapies (ACTs) is an emerging challenge. Our study aimed to evaluate the therapeutic efficacy of combining Artemether-Lumefantrine with crude root bark extract of Hippocratea africana, on mice infected with Plasmodium berghei. Forty-five albino mice which weighed 30 - 38g were grouped into five with seven mice in each. The mice were inoculated intraperitoneally with Plasmodium berghei and kept for seven days for the parasitaemia to develop. A daily single dose of 200mg/Kg body weight of extract of H. africana was administered orally for ten days, while therapeutic dose of Artemether-lumefantrine was administered as daily single dose to the relevant groups on the last six days of treatment. A non-parasitized and parasitize untreated groups served as controls. The weights of the animals were recorded before and after treatment. The animals were sacrificed and blood obtained for determination of percentage parasitaemia and the erythrocytes count of the parasitized mice using standard methods. The results showed the mean body weight and percentage body weight changes of parasitized mice treated with combination of ACT plus H. africana not statistically different from those of non-parasitized untreated mice. Parasitized mice treated with ACT plus Extract had a significantly (p < 0.05) reduced percentage parasitaemia when compared with those treated with ACT only. Treatment with ACT plus Extract also showed a significant increase in parasite clearance (100%) when compared to mice treated with either ACT only (93.10%) or Extract only (82.15%). We concluded that combining artemether, lumefantrine and H. africana root bark extract exhibited a good therapeutic efficacy as demonstrated by body weight recovery, parasite clearance and reversion of clinical signs induced by Plasmodium berghei parasitaemia. The triple regimen was more efficacious than ACT alone, and therefore, may be a useful regimen in addressing the emerging problem of resistance of plasmodium species to standards ACTs.