Effect of praziquantel treatment on the activities of some liver microsomal enzymes in mice infected with Schistosoma mansoni.

One of the most commonly used drugs for clinical management of schistosomiasis is praziquantel (PZQ, CAS 55268-74-1). Now, PZQ is recognized, world wide, as a powerful therapeutic agent for the control of schistosomiasis. Previous studies have shown decreased activities of some of the microsomal drug-metabolizing enzymes in the livers of S. mansoni-infected mice. Consequently, this work was initiated in order to investigate the effect of PZQ treatment (in a total dose of 1000 mg/kg given on two consecutive days each of 500 mg/kg body weight) administered to mice with or without previous S. mansoni infection on selected liver microsomal drug-metabolizing enzymes. The effect of these factors on liver function was also studied. The drug was given orally seven weeks after infection with 80 Egyptian strains of S. mansoni cercariae/mouse. The activities of aminopyrine-N-demethylase, aniline hydroxylase and the hepatic glutathione content as well as the concentrations of gamma-glutamyl transferase were measured after different time intervals following the second dose of PZQ treatment. The results indicated a meaningful decrease in the activities of aminopyrine-N-demethylase and aniline hydroxylase and a high elevation in the concentrations of gamma-glutamyl transferase and the contents of hepatocellular glutathione in mice infected with S. mansoni compared with their corresponding control groups. After two weeks following the praziquantel treatment, there was an improvement in the activities of these enzymes towards the control values. Collectively, the present findings point to the importance of initiating more studies in this discipline and careful deliberation of results in order to fully understand the possible interactions of antibilharzial drugs with the liver microsomal drug-metabolizing enzymes.