In Vitro Scolicidal Effect of Urtica dioica and Pyrus boissieriana Extracts Against Protoscoleces of Echinococcus granulosus

Background: Cystic echinococcosis (CE) is one of the most important neglected diseases and a public health concern worldwide. Due to the poor efficacy of current drugs, novel therapeutic approaches are urgently needed. Objectives: This study evaluated the scolicidal effects of the hydroalcoholic extract of Urtica dioica and the chloroformic extract of Pyrus boissieriana on protoscoleces of CE cysts. Methods: Protoscoleces were aseptically aspirated from the livers of sheep naturally infected with CE cysts. To assess the scolicidal effect of these herbal extracts, various concentrations of both extracts (5, 10, 20, 40, and 80 mg/mL) were added to a suspension of 3 × 103 washed protoscoleces. After 10, 20, 30, 60, and 120 minutes of exposure, eosin stain was added to each tube, and the viability of protoscoleces was evaluated by flame cell motility under a light microscope, as well as impermeability to 0.1% eosin solution. All experiments were performed in triplicate. Results: The scolicidal effects of U. dioica extracts at a concentration of 80 mg/mL were 81% and 89% after 60 and 120 minutes of exposure, respectively. Almost the same results were obtained for P. boissieriana extracts at a concentration of 80 mg/mL (81.33% and 89% after 60 and 120 minutes of exposure, respectively), which were significantly different from the negative control group (P < 0.001). However, the extract of U. dioica exhibited stronger scolicidal effects compared to the extract of P. boissieriana at concentrations lower than 40 mg/mL (P < 0.001). Conclusions: The present findings indicate that both U. dioica and P. boissieriana extracts possess high protoscolicidal activities and could be used as alternative natural medicines in the treatment of CE. However, further studies are required to verify these findings through assessment in animal models and clinical subjects.