Evaluation of Therapeutic Efficacy of Mucus and Tissue Extracted from Biomphalaria alexandrina Snails on Mice Infected with Schistosoma mansoni

Abstract Schistosomiasis is a neglected tropical disease with considerable morbidity. Praziquantel though safe and efficacious does not prevent reinfection and the emergence of drug resistance is of great concern. This study was done to evaluate the therapeutic efficacy of mucus and nucleoproteins extracted from Biomphalaria alexandrina snails on miracidia, cercariae and Schistosomamansoni adults in vitro and assess their in vivo effect on mice experimentally infected with Schistosoma mansoni through parasitological, pathological and biochemical parameters.The in vitro study proved that the mucus had a better lethal effect on cercariae than miracidia, on contrast to NPs which was better on miracidia. The mucus effect surpassed the NPs as regard the lethal effect on adults in vitro. The effect of mucus on S. mansoni females and males was almost equivocal except for the effect after 72 hours where 80 µg/ml caused 100% lethal effect on adult females. The effect of NPs on S. mansoni adult females was better than adult males at the highest used concentration of 100 µl/ml after 72 hours with a 60% lethal effect. However, at 48 hours the same concentration had a better lethal impact on males (25%) than females (20%). The in vivostudy proved that the combined NPs or mucus to PZQ added to the effect of individual PZQ considering its effect on ova count, oogram pattern and granuloma parameters. The histopathological results denoted a relevant potential for NPs when compared to the rest of the groups and the control though, the PZQ still showed the best findings. The effect of PZQ alone or combined with mucus or NPs was equivocal resulting in 100% TWB reduction. As regard oxidative stress markers, NO decreased level was best shown by combined PZQ and NPs, while, as regard GSH level, the individual PZQ showed the best increased level. This study concluded that mucus and NPs had cercaricidal, miracidial and antischistosomal effect in vitro and that their combination could be considered as a sharing therapeutic adding to PZQ potentiality in vivo for the treatment of schistosomiasis for further investigations.