Protoscolicidal effects of chenodeoxycholic acid on protoscoleces of Echinococcus granulosus.

Dissemination of protoscoleces-rich fluid during surgical operation for cystic echinococcosis is a major cause of its recurrence. Instillation of a scolicidal agent into hydatid cysts to reduce the risk of spillage of viable protoscoleces is an integral part of the surgical technique employed by many surgeons. In this study, the protoscolicidal effect of chenodeoxycholic acid (CDCA) was investigated. Freshly isolated protoscoleces were subjected to CDCA treatment (500, 1000, 2000, and 3000 μmol/L), and the effects on protoscoleces were investigated with the help of 0.1% eosin staining, electron microscopy, and colorimetric assay of caspase-3 like activity. Dose-dependent mortality of Echinococcus granulosus protoscoleces was observed within a few days of CDCA treatment. The treated protoscoleces showed loss of viability, and morphological changes such as contraction of the soma region, formation of blebs, rostellar disorganization, loss of hooks, destruction of microtriches, and formation of vesicles, lipid droplets, and lamellar bodies. Apoptosis was evident in the treated protoscoleces, as compared to the control group, which were cultivated for nearly 3 months. Our study indicates a therapeutic potential for CDCA as a protoscolicidal agent against E. granulosus. However, further studies are needed to test the long-term effects of CDCA in animal models.