EJMS

Abstract

The treatment of schistosomiasis relies on a single drug, praziquantel; hence, there is a need to develop new antischistosomal drugs. The purpose of the present study ia to assess the parasitological, histopathological and immunological changes in mice infected with Schistosoma mansoni. Mice were treated with parziquantel, myrrh and combined reduced doses od both drugs 49 days post infection. Two weeks post treatment mice were sacrificed. Results: Worm burden and distribution: Praziquantel was more effective in reduction of the total worm burden(% reduction was 99%) while myrrh produced the least observed changes in reduction of worm burden as only slight reduction in worm burden was observed (%reduction was 3.86%). As for worm distribution, complete disappearance of S. worms from portomesentric vasculature associated with marked reduction of hepatic worm load in mice treated with PZQ full dose, while in mice treated with myrrh full dose alone, there is no change in the hepatic worm load associated with slight portomesentric reduction. In the lat group treated with combined reduced dose, moderate reduction of both hepatic and portomesentric worm load was observed. Tissue egg load showed more reduction of the mean total tissue egg load(hepatic and intestinal) was found in PZQ full dose treated mice (% reduction was 63.6% and 94.2% respectively), while mice treated with combined reduced dose of both drugs, the tissue egg load % reduction was 44.8% and 89.9% in hepatic and intestinal egg load respectively. Myrrh did not cause significant reduction either hepatic or intestinal tissue egg load (% reduction in hepatic and intestinal egg load was 13.55 and 20.01% respectively). Oogram pattern changes shwoed: all stages of ova development were found in untreated control mice, similar finding was observed in mice treated with myrrh full dose (eggs of all developmental stages were observed). In contrast, PZQ full dose produced complete disappearance of immature ova, marked reduction of mature ova (%reduction was 94.5%) associated with marked increase of dead ova to 97.9% of all detected ova. Similar but less prominent findings were observed in mice treated with combined reduce dose of both PZQ and myrrh, as their was marked reduction (but not complete disappearance of immature ova associated with 72.3% reduction of mature ova with moderate increase of dead ova to 86.08%. Regarding Hepatic granuloma (number and diameter) The largest mean granuloma diameter was recorded in untreated control mice, while PZQ was more effective of both granuloma size and number (% reduction in granuloma size and number was 51.2% and 54.7% respectively) minimal insignificant changes was observed in mice treated with myrrh alone (%reduction in granuloma size and number was 13.6% ad 11.6% respectively). In Serological findings The level of antibodies, whether IgG, or IgM were shown to be significantly elevated in both PZQ and combined reduced dose treated mice groups( OD was 2.4 and 2.1 compared to 1.4 in untreated controls. In the last group treated with myrrh full dose, there is insignificant increase of OD level (OD was 1.8 compared to 1.4 in untrated controls).