Spillage of cyst contents during surgical operation is the major cause of recurrence after hydatid cyst surgery. Instillation of a scolicidal agent into a hepatic hydatid cyst is the most commonly employed measure to prevent this complication. SB202190 is a pyridinyl imidazole derivative and is known to be a specific inhibitor of p38 MAPK. In the present study, the scolicidal effect of SB202190 was investigated. Freshly isolated Echinococcus granulosus protoscolices were subjected to SB202190 treatment (10, 20, 40, and 80 µM), and the effects on parasite viability were monitored by trypan blue staining. Corresponding effects were visualized by scanning and transmission electron microscopy. Dose-dependent protoscolex death within a few days of SB202190 treatment was observed. Although the in vitro scolicidal effect of SB202190 was satisfactory, the in vivo efficacy of this drug and also possible side effects remain to be further investigated.

Cystic echinococcosis is a severe parasitic disease that commonly affects the liver and causes abscesses or rupture into the surrounding tissues, leading to multiple complications, such as shock, severe abdominal pain, and post-treatment abscess recurrence. Currently, there are no efficient measures to prevent these complications. We previously confirmed that arsenic trioxide (As₂O₃) exhibited in vitro cytotoxicity against Echinococcus granulosus protoscoleces. In the present study, we aimed to explore the mechanism of As₂O₃-induced E. granulosus protoscoleces apoptosis. After exposing E. granulosus protoscoleces to 0, 4, 6, and 8 μM As₂O₃, reactive oxygen species (ROS) level was detected by fluorescence microscopy; superoxide dismutase (SOD), and caspase-3 activities were measured; intracellular Ca²⁺ was detected by flow cytometry; GRP-78 and caspase-12 protein levels were measured by western blot analysis. Our results showed that the expression of caspase-3 was gradually increased and the expression of SOD was gradually decreased in As₂O₃-treated groups of protoscoleces. Simultaneously, fluorescence microscopy and flow cytometry showed that the ROS level and the intracellular Ca²⁺ level were increased in a time- and dose-dependent manner. Western blot analysis showed that the expressions of GRP-78 and caspase-12 were higher in As₂O₃-treated groups than in the control group. These results suggest that As₂O₃-induced apoptosis in E. granulosus protoscoleces is related to elevation of ROS level, disruption of intracellular Ca²⁺ homeostasis, and endoplasmic reticulum stress. These mechanisms can be targeted in the future by safer and more effective drugs to prevent recurrence of cystic echinococcosis.

Spillage of cyst contents during surgery is the major cause of recurrences of hydatidosis, also called cystic echinococcosis (CE). Currently, many scolicidal agents are used for inactivation of the cyst contents. However, due to complications in the use of those agents, new and more-effective treatment options are urgently needed. The aim of this study was to investigate the in vitro efficacy of arsenic trioxide (ATO) against Echinococcus granulosus protoscolices. Protoscolices of E. granulosus were incubated in vitro with 2, 4, 6, and 8 μmol/liter ATO; viability of protoscolices was assessed daily by microscopic observation of movements and 0.1% eosin staining. A small sample from each culture was processed for scanning and transmission electron microscopy. ATO demonstrated a potent ability to kill protoscolices, suggesting that ATO may represent a new strategy in treating hydatid cyst echinococcosis. However, the in vivo efficacy and possible side effects of ATO need to be explored.