Antischistosomal Effects of Selected Methanolic Plant Extracts in Swiss Albino Mice Infected with Schistosoma mansoni

Aim: Schistosoma mansoni is a parasite of medical importance because it is the causative agent of intestinal schistosomiasis. The present study was designed to assess the in vivo antischistosomal effects of methanolic extracts of three food plants: Apple (Malus domestica), Lemon (Citrus limon) Original Research Article Muema et al.; EJMP, 9(1): 1-11, 2015; Article no.EJMP.16953 2 and Onion (Allium cepa) on Swiss Albino mice infected with Schistosoma mansoni. Study Design: Swiss albino mice were infected and randomized into groups of five for plant extract treated groups (high and low dosages), negative control were given a vehicle administered via intraperitoneal route twice daily for five days 7 weeks post-infection after which percentage worm reduction and glutathione levels were evaluated. Place and Duration of Study: The study was conducted at the Centre of Biotechnology Research and Development (Animal Facility), Kenya Medical Research Institute from July, 2013 to May, 2014. Methodology: Swiss albino mice infected with 90 cercariae each were administered with high and low dosages of plant extracts twice daily for five days (7 weeks post-infection) after which worm densities and hepatic oxidative stress were assessed. Results: In general, upon administration of increased concentration of the plant extracts, there was significant (P<0.05) reduction in worm densities with a concomitant increase in GSH activity. Malus domestica showed significant (P<0.05) antischistosomal activity at concentrations 300 mg/kg and 200 mg/kg giving 85.93% and 72.22% worm reduction respectively, Allium cepa at concentrations 500 mg/kg and 300 mg/kg gave 72.59% and 58.52% respectively, with least worm reduction resulting from treatment with Citrus limon at dosages of 200 mg/kg and 100 mg/kg (42.96% and 29.63% respectively). Conclusion: The data demonstrated that, treatment of mice with plant extracts ameliorated oxidative stress induced by Schistosomiasis as indicated by significant (P<0.05) improvement of GSH level compared to schistosome-infected control group. This is expected to have serious ramifications on the management of this tropical disease which hitherto is solely dependent on the use of drugs.