Echinococcus granulosus: In vitro effectiveness of warm water on protoscolices

Hydatid disease is one of the most important helminthic diseases worldwide. Hydatid cysts may be found anywhere in the body. The most effective treatment of hydatid cyst is surgical operation. Spillage of live protoscolices during the operation is the major cause of recurrence. Instillation of scolicidal agent into hydatid cyst is the most commonly employed measure to prevent this complication. To date, many scolicidal agents have been used for inactivation of the hydatid cyst content, however, most common scolicidal agents may cause unacceptable side-effects, limiting their use. In this study the scolicidal effect of warm water (45, 50, 55, and 60 °C) at different exposure times (1, 2, 3, 4, 5, 6, 8, 10, 12, and 15 min) is investigated. Protoscolices were collected aseptically from sheep livers containing hydatid cyst. Viability of protoscolices was determined by 0.1% eosin staining. Even though the highest scolicidal activity of warm water at 45 °C was 40.4% at the end of 15 min, the best scolicidal effect (100%) of warm water at 50, 55, and 60 °C was obtained after 5, 2, and 1 min, respectively. The results of this in vitro study showed that warm water at 50–60 °C can be regarded as an effective scolicidal agent. Warm water is commonly available, easily prepared, and inexpensive. In vivo scolicidal activity of warm water and also the possible side effects need further investigation.     

In vitro Scolicidal effects of Androctonus crassicauda (Olivier, 1807) venom against the protoscolices of Echinococcus granulosus

Hydatidosis is a zoonotic disease that commonly occurs in several places around the world, especially in the Middle East, due to infection by the larval stage of Echinococcus granulosus. This disease impacts an immense effect on the economic and public health of both humans and animals. Despite their effectiveness, the unacceptable side effects and progressive resistance to scolicidal agents may limit their use. According to their biopharmaceutical activity and benefits, numerous studies have reported that scorpion venom and its derivatives represent important resources for therapeutic applications. Therefore, this study was designed to investigate the in vitro scolicidal consequences of the crude venom of Androctonus crassicauda on E. granulosus. For this purpose, protoscolices from infected organs of camel containing hydatid cysts were collected, separated, and washed. The scolicidal impacts of three different concentrations of the crude venom (20, 50, and 100 µg/mL) were tested at different times of exposure (30, 60, 120, and 240 min). Particularly, eosin exclusion test was used to examine the viability of the protoscolices. The study results showed that the crude venom at 100 μg/mL destroys all protoscolices after 240 min incubation. Also, the scolicidal activity of venom increased significantly according to the time of exposure. In conclusion, the crude venom of A. crassicauda demonstrated high scolicidal activity in vitro against protoscolices of hydatid cysts in low concentration and short exposure time. However, the efficacy of scorpion venom remains to be evaluated in vivo for the treatment of hydatidosis in both humans and domesticated animals.     

Efficacy of thymol against Echinococcus granulosus protoscoleces

The aim of the present work was to determine the in vitro protoscolicidal effect of thymol against Echinococcus granulosus. Protoscoleces of E. granulosus were incubated with thymol at concentrations of 10, 5 and 1 μg/ml. The first signs of thymol-induced damage were observed between 1 and 4 days post-incubation. The maximum protoscolicidal effect was found with thymol at 10 μg/ml, viability reduced to 53.5 ± 11.9% after 12 days of incubation. At day 42, viability was 11.5 ± 15.3% and, reached 0% after 80 days. Thymol at concentrations of 5 and 1 μg/ml provoked a later protoscolicidal effect. Results of viability tests were consistent with the tissue damage observed at the ultrastructural level. The primary site of damage was the tegument of the parasite. The morphological changes included contraction of the soma region, formation of blebs on the tegument, rostellar disorganization, loss of hooks and destruction of microtriches. The data reported in this article demonstrate a clear in vitro effect of thymol against E. granulosus protoscoleces.