Effect of schistosome infection on hepatic drug metabolising enzymes

Schistosomiasis is a parasitic disease that affects over 200 million persons worldwide.' The disease is caused by infection with any one of several species that are known to affect humans. Infected persons are likely to be consuming a wide spectrum of xenobiotics such as drugs and environmental toxins. The drugs consumed would not only include praziquantel and other schistosomicides, but also those used for the treatment of other parasitic diseases such as antimalarials, anthelmintics and antibiotics. Experiments involving humans and experimental animals suggest that infection with schistosomes causes a reduction in the host's ability to metabolise and remove drugs from the b~dy.~.~ The metabolic fate of drugs is dependent to a large extent on the expression and activity of the microsomal drug metabolising enzyme^.^^^ These enzymes include the microsomal cytochrome P-450 dependent monooxygenase system and the uridine diphosphate glucuronosyl transferases as well as other cytosolic enzymes such as glutathione S-transferases. This article reviews the effects of experimental Schistosoma mansoni infection on hepatic drug metabolising enzyme activity.,Research Board, University of Zimbabwe, and the International Programs in the Chemical Sciences, Uppsala, Sweden