Efficacy of maslinic acid and chloroquine on the co-infection of Plasmodium berghei and Trichinella zimbabwensis in Sprague-Dawley rats.
Many people living in Africa and elsewhere in the tropics suffer from combined malaria, soil-transmitted infections and tissue-dwelling nematodes. Most of these deaths are prevalent in sub-Saharan Africa (SSA) where the infections overlap, which often results in co-infection. Malaria and trichinellosis are one of the most important zoonotic diseases especially in sub-Saharan Africa caused by Plasmodium spp. and Trichinella spp., respectively. New drugs targeting malaria and trichinellosis have been examined with little success. The aim of our study was to determine and compare the efficacy of maslinic acid and chloroquine on the co-infection of muscle-dwelling larvae of Trichinella zimbabwensis and Plasmodium berghei in rats. Fifty-four Sprague-Dawley rats with an average weight of 150g and 200g for males and females respectively were infected with T. zimbabwensis and P. berghei. Infected rats were randomly assigned to nine groups which were subjected to treatments of maslinic acid and chloroquine and a combination of maslinic acid and chloroquine. Co-infected groups were infected with T. zimbabwensis on day 0, and then infected with P. berghei on day 30 post-infection (pi). Treatment was administered for 3 consecutive days on day 9 pi with P. berghei. Groups infected with P. berghei only were infected on day 0 and were treated on day 9 pi for 3 consecutive days. Groups infected with T. zimbabwensis only were infected on day 0 and treated on day 25 pi. Untreated control groups were a placebo (distilled water) on day 25 pi infected with T. zimbabwensis and from day 9 pi infected with P. berghei. In Trichinella-infected groups, the efficacy of each treatment measured by the rate of the reduction in muscle larvae was significant (P < 0.05) for both drugs compared to the untreated control group. In malaria-infected groups, the efficacy of each treatment, measured by the rate of reduction in parasitaemia, was significant (P < 0.05) for both drugs compared to the untreated control group. There was no apparent synergistic effect due to the combination of the two drugs in reducing the muscle larval burden and in reducing malaria parasitaemia. In all the treatment regimens, the reductions were significant when compared to the untreated control groups and not significant to each other (P > 0.05). From these results we can conclude that the efficacy of maslinic acid on the co-infection of T. zimbabwensis and P. berghei was comparable to that of chloroquine, making maslinic acid a promising drug to be used as an anthelmintic and anti-malaria against muscle larval stages of Trichinella spp. and malaria parasitaemia and no side effects were observed.