Chemotherapeutic efficacy of a natural combination in the treatment of mansonic schistosomiasis: an experimental study

Rashad Abdul-Ghani¹, Naguiba Loutfy², Manal Sheta³, Azza Hassan^2
1Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; ²Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, Egypt

Purpose: Combination chemotherapy of Schistosoma mansoni has been studied previously, with praziquantel being the basis of combination. Artemether and myrrh are compounds of a natural origin that have been investigated experimentally and clinically against schistosomiasis. Artemether is used as an antimalarial drug, and has been used as a chemoprophylactic drug against Schistosoma japonica in China whereas myrrh extract is manufactured and prescribed as an antischistosomal drug in Egypt. The present study investigated the experimental efficacy of combining artemether and myrrh using three different protocols in mice infected with the Egyptian strain of S. mansoni.
Methods: Experiments were performed on 40 eight-week-old female Swiss albino mice divided into three experimental groups and one control group. Assessment of efficacy was based on a suite of parasitologic and histopathologic parameters. Parasitologic parameters included reductions in total and female worm burdens, reductions in hepatic and intestinal wall tissue egg loads, and alterations in oogram patterns in the experimental groups compared to the infected untreated control. Histopathologic parameters comprised microscopic examination of liver sections stained with hematoxylin and eosin to study the reductions in the mean counts and diameters of hepatic granulomas as well as their healing ratios compared to the control.
Results: Reductions of 43.9%–58.2% in total worm burdens and 42.4%–63.7% in female worm burdens were induced. Meanwhile, significant reductions of 63.1%–77.8% in eggs per gram of small intestinal tissue and of 56.5%–66.3% in eggs per gram of liver tissue were also observed. The combination also caused alterations in the oogram pattern as well as amelioration of hepatic lesions as evidenced by increased ratios of healed granulomas in the treated groups compared to the control.
Conclusion: The experimental efficacy of the artemether–myrrh combination against the Egyptian strain of S. mansoni was evident, but not to an extent that would warrant clinical trials in humans.

Keywords: Schistosoma mansoni, combination chemotherapy, artemether, myrrh, natural drugs