Parasitological and histo-pathological studies on schistosomiasis mansoni infected mice and treated with praziquatel and/or oltipraz

Abstract

A total of 120 albino mice were divided into: G1 (80 infected with S. mansoni cercariae by tail immersion) and G2 (40 uninfected controls). Seven weeks after infection, G1 was subdivided into four subgroups of 20 mice each. Gla: Infected untreated control. G1b: treated with Praziquantel (PZQ) in a dose of 500 mg/kg for two consecutive days. G1c: treated with Oltipraz (Oz) in a dose of 500 mg/kg for three consecutive days. G1d: treated with combination of PZQ and Oz (1/3 therapeutic dose of both for two consecutive days. G2 was divided into 4 subgroups of ten mice each. G2a: non infected non treated. G2b: PZQ treated (PZQ control positive). G2c: Oz treated (Oz control positive). G2d: Drugs treated (PZQ and Oz control positive). The effect of drugs was done 2 weeks post-treatment, parasitologically to detect number of worms and the distribution in liver vasculature after perfusion of hepatic circulation of mice, and number of eggs per gram of liver tissue. Also, histopathological examination of liver samples with H& E and/or Masson's trichrome stains showed effect on granuloma and tissue. PZQ gave reduction of total worm burden to 0.22 + 0.01 (99%), while Oz gave 22.4 + 0.57 (3.6%). PZQ produced marked hepatic shift while Oz gave 6.14%efficacy. A decrease in egg number with PZQ was 63.69%. Oz gave 13.5%. Complete disappearance of immature ova with increase no. of dead ones was 97.89% of mature ova stage to 2.11% after PZQ. Oz gave 45% of all detected ova with slight increase of dead ones to 14.18% compared to 9.8% in infected control. Improvement of hepatic pathology in form of 51.2% reduction in granuloma size and 54.7% decrease in number with improvement of hepatocytes was after treatment with PZQ in contrary to Oz as reduction of size and number of granuloma was 13.6% and 21.6% respectively. Combination of reduced dose of both drugs produced moderate effect on all criteria less than that detected with full dose of PZQ, but much better that obtained after Oz.