ABSTRACT
The toxicity of selenium on Biomphalaria alexandrina snails, the intermediate host for Schistosoma mansoni, was traced by studying its effect on the protein profile, free amino acids [FAA] and some urea cycle enzymes; namely, ornithine aminotransferase, argininosuccinate synthetase and arginase in hepatopancreas of snails. The results revealed that treatment with 15 ppm selenium dioxide [SeO2] caused an elevation in the protein content and a variation in the percentage and number of the different polypeptides as obtained by gel electrophoresis and a remarkable reduction in all FAA, except arginine alanine and threonine. On the other hand, the activity of ornithine aminotransferase was elevated, whereas that of arginase was reduced. The study was a trial to focus on some metabolic disorders caused by SeO2 on the physiological status of these intermediate host snails, which may greatly control parasite-host association. Thus, the life cycle of the parasite within its respective host may be disturbed
Subject(s)
Schistosomiasis mansoni/parasitology , Selenium/pharmacology , Nitrogen/metabolism , SnailsABSTRACT
In the present work, five antigenic fractions were prepared from Biomphalaria alexandrina snails. These antigens were immunized into five different groups of mice. The effect of these antigens on the serum enzyme activity levels, namely transaminase [GOT and GPT], alkaline phosphatase [alk-phase] and 5-nucleotidase [5- Nase], was studied and compared to those of non-immunized mice. In addition, the activity levels of these enzymes were also studied in control and immunized mice 10 weeks post infestation with cercariae of the Egyptian strain Schistosoma mansoni. Significant decreases were observed in the activity levels of GOT, GPT, Alk-phase and 5-Nase in the infested immunized mice as compared to the infested non-immunized mice. These results indicated the efficiency of these antigens in reducing the damaging effect caused by parasitic infestation