In vitro protoscolicidal effects of hypertonic glucose on protoscolices of hydatid cyst

Protoscolicidal effects of curcumin nanoemulsion against protoscoleces of Echinococcus granulosus

BACKGROUND

The aim of the present study was to assess in vitro protoscolicidal effects of curcumin nanoemulsion (CUR-NE) against protoscoleces of cystic echinococcosis (CE)/hydatid cysts.

METHODS

The CUR-NE was prepared via spontaneous emulsification of soybean as the oil phase, a mixture of Tween 80 and Tween 85 as the surfactant, ethanol as the co-surfactant and distilled water. Various concentrations of CUR-NE (156, 312, 625 and 1250 µg/ml) were exposed to collected protoscoleces of infected sheep liver hydatid cysts for 10, 20, 30, 60 and 120 min. Viability of the protoscoleces were assessed using eosin exclusion test. Morphological changes of the protoscoleces were observed using differential interference contrast (DIC) microscopy.

RESULTS

The mean particle size and zeta potential of CUR-NE included 60.4 ± 14.8 nm and - 16.1 ± 1.1 mV, respectively. Results showed that the viability of the protoscoleces decreased significantly with increases in CUR-NE concentrations (p < 0.001). The mortality rates of protoscoleces with exposure to concentrations of 1250 and 625 µg/ml of CUR-NE for 60 min were 94 and 73.33%, respectively. Mortality of the protoscoleces was 100% after 120 min of exposure to 1250 and 625 µg/ml concentrations of CUR-NE. Using NIC microscopy, extensively altered tegumental surface protoscoleces was observed after protoscoleces exposure to CUR-NE.

CONCLUSION

The findings of the present study revealed the in vitro protoscolicidal potential of CUR-NE. Therefore, CUR-NEs are addressed as novel protoscolicidal agents, which can be used as an alternative natural medicine to kill the protoscoleces, owing to their low toxicity and significant inhibition potency. However, further studies are necessary to investigate pharmacologic and pharmacokinetics of CUR-NEs.

Anti-hydatidosis Potential of Sodium Valproate: Evaluating New Therapeutic Potential for Sodium Valproate

Background: Larval stage of Echinococcus granulosus is the main cause of the hydatid cyst. Surgery, which is both aggressive and high-risk, is the most common treatment for this type of cyst. Some medicines, such as mebendazole, are also used as a complementary approach to preventing the recurrence of hydatid cysts. Objectives: Considering the approved antiparasitic effects of sodium valproate (VPA) on some parasites, this research intended to examine the potential of VPA against protoscolices and hydatid walls. Methods: Liver hydatid cysts caused by E. granulosus were collected from a slaughterhouse. Protoscolices and hydatid cysts were exposed to RPMI and dimethyl sulfoxide (DMSO) media (control groups) or different concentrations of VPA and mebendazole in vitro. The viability of protoscolices was evaluated via light microscopy. Also, tissue changes and expression of apoptotic caspase-3 were examined in hydatid cyst walls (HCWs) using histological and immunohistochemical methods, respectively. Results: The mortality rates of VPA-treated and mebendazole-treated protoscolices were dose- and time-dependent. There was a significant difference between the intervention and control groups (P < 0.05). Tissue changes and apoptosis were observed in VPA-treated and mebendazole-treated HCWs. Conclusions: Valproate and mebendazole had significant effects on protoscolices and HCWs, although VPA exerted its effects more rapidly. It seems that VPA can be a new promising protoscolicidal agent and anti-hydatid medicine.

In vitro protoscolicidal effects of lithocholic acid on protoscoleces of Echinococcus granulosus and its mechanism

Surgery has been found to be the best choice of treatment for hydatidosis. However, leakage of cyst contents during surgery is the foremost reason for recurrence of hydatidosis. In this study, we investigated the in vitro efficacy of lithocholic acid (LCA) against Echinococcus granulosus protoscoleces. The protoscoleces were divided into a control group, an albendazole (ABZ) positive control group and LCA intervention groups at concentrations of 0.5, 1, 2, and 3 mmol/L and stained with 0.1% eosin for observation using an inverted microscope; the protoscolecal ultrastructure was examined with SEM and TEM; the activities of ROS, SOD, and caspase-3 were investigated using an ROS kit, SOD kit, and caspase-3 kit, respectively; the contents of HO-1 and NQO-1 were analyzed by enzyme-linked immunosorbent assay; and the expression level of cytochrome c (Ctyc) was analyzed by western blotting. Results: As the concentration of LCA increased, the survival rate of protoscoleces gradually decreased. The microstructure shows that the external shape and internal structure were gradually deformed and collapse. SOD, GSH, HO-1 and NQO-1 decreased more significantly in the 3 mmol/L LCA group. However, ROS levels gradually increased. LCA treatment for 3 days at all concentrations significantly increased caspase-3 activity and expression in a dose-dependent manner. LCA decreased the level of Ctyc protein in vitro. LCA demonstrated a parasiticidal effect on the protoscoleces of Echinococcus granulosus in vitro. LCA may induce apoptosis of E. granulosus protoscoleces by oxidative stress and mitochondrial pathways.

Study on the effect of an ion channel inhibitor "Fluralaner" on Echinococcus granulosus protoscolices and metacestode layers in vitro

Hydatid disease has a great impact on public health, causing high morbidity and mortality. Main lines of treatment include surgery, which mostly requires the installation of a scolicidal agent into hydatid cysts to prevent dissemination. Alternatively, medical treatment involves the use of benzimidazole drugs; however, the results are not satisfactory, and new drug compounds are urgently needed. Fluralaner is a potent inhibitor of GABA-gated chloride channels and L-glutamate-gated chloride channels (GluCls) providing immediate and persistent flea, tick and mite control in dogs after a single oral dose. Researches previously identified different genes encoding ion channels in Echinococcus granulosus, making ion channel inhibitors a promising target for treating hydatid disease. Thus, the present study aimed to evaluate the effect of fluralaner on protoscolices and metacestode layers. Parasite materials (Protoscolices, Metacestodes layers) were exposed to different concentrations of the drug ranging from "12.5-100 ug/ml" and examined for viability after 1, 6 and 24 h. Morphological and ultrastructural alterations were recorded by both light and electron microscopies. Immunohistochemical staining confirmed caspase-3 activation as an indicator of apoptosis- induced therapy. The treated protoscolices and metacestode layers showed loss of the viability, the formation of vacuoles and lipid droplets, separation of the germinal layer, and damage in the laminated layer; apoptosis was prominent after treatment. These findings revealed that fluralaner has a potent scolicidal activity and suggested its therapeutic potential against hydatid disease. Further evaluations for animals and human use in the treatment and prevention of hydatid disease are needed.

Genetic Diversity of Hepatic/Non-Hepatic Cystic Echinococcosis in Baqiyatallah Hospital, Tehran, Iran

BACKGROUND

Cystic echinococcosis (CE) is a worldwide zoonotic helminthic disease caused by the larval stage of Echinococcus granulosus. The infection is particularly important in terms of economic and medico-veterinary aspects in endemic areas including Iran. Considering the possibility of organ-tropism in E. granulosus strains, the present study was aimed to identify the genotypes of E. granulosus in different organs involved in patients, undergone surgery in Baqiyatallah Hospital, Tehran, Iran from 2005-2015.

METHODS

Overall, 29 formalin-fixed paraffin-embedded tissues (FFPT) from patients with histologically confirmed CE including liver (N: 14) lungs (N: 6) abdomen (N: 2), pancreas (N: 2) and each of spleen, gallbladder and, muscles (N: 1) plus unknown organs (N: 2) were used and genetically characterized using polymerase chain reaction, followed by partial sequencing of mitochondrial cytochrome c oxidase gene subunit 1(cox1) and analyzed.

RESULTS

Nineteen out of 29 isolates including liver (N: 6) lungs (N: 4) abdomen (N: 2), pancreas (N: 2) and each of spleen, gallbladder, and muscle (N: 1), unknown organs (N: 2) obtained from paraffin-embedded blocks of human CE created an acceptable sequence in two directions. All 19 isolates regardless of the organ involved were recognized as E. granulosus sensu stricto (G1).

CONCLUSION

The sequence alignments of the isolates displayed two profiles. All sequenced samples showed E. granulosus sensu stricto (G1) with no organ-related genotype.

Echinococcus Granulosus in Childhood: A Retrospective Study of 187 Cases and Newer Data

Echinococcus granulosus, first reported by Goeze in 1782, is the causative parasite of cystic echinococcosis (hydatidosis) especially for countries that are endemic areas. Since the 1970s, the incidence of echinococcosis in Greece has been very high. Nevertheless, with the implementation of special prevention measures in the 1980s, a large reduction in the incidence of hydatidosis meant that it reached European levels. Therefore, we analyzed the demographics, multiple organ localizations of the parasite, diagnosis, and conservative and optimal surgical treatment over a total period of 39 years, especially for pulmonary and hepatic echinococcosis in children. The higher incidence of pulmonary echinococcosis compared with other localizations, male predominance, wide range of age, and various cystic sizes were some of the main demographics. Because cystic echinococcosis remains a main public health problem, we advocate a meticulous clinical investigation and treatment methodology to bridge the gap between knowledge and awareness of this important disease.

In-vitro evaluation of Nigella sativa and Punica granatum effect on protoscolices of hydatid cysts

Cystic echinococcosis (CE) are commonly found in the liver and lungs of affected hosts. The treatment approach is usually surgical, or giving drugs in conjunction before surgery to kill protoscolices, to avoid anaphylactic shock from leakage of hydatid fluid into the peritoneum and to decrease opportunities for recurrences. The present study was to evaluate the in vitro scolicidal efficacy of hydroalcoholic extract of Punica granatum peel and Nigella sativa, on the protoscolices of CE that collected from the lungs of infected camels. Different concentrations of extracts with different exposure times were used and a viability assay was applied to measure the scolicidal effect. N. sativa showed its highest scolicidal efficacy at 100 mg/mL and 10 mg/mL concentrations after 30 and 60 min. P. granatum peel extract showed its maximum scolicidal efficacy at 100 mg/mL concentration after 120 min. All experiments of the current study revealed that the extracts of both N. sativa and P. granatum had a scolicidal effects on the protoscolices of camel hydatid cysts. It could be concluded that N. sativa extract is more potent than P. granatum peel extract regarding scolicidal effect, but the efficacies of both extracts were of moderate significant correlation to exposure time and concentrations.

In Vitro Study on Protoscolicidal Effect of Methanolic Extract of Allium hirtifolium on Protoscoleces of Cystic Echinococcosis

BACKGROUND

Cystic echinococcosis/ hydatidosis is one of the most important parasitic zoonoses worldwide. Usually, surgery is used for the treatment of active cysts. Due to the risk of cyst rupture during surgery, a protoscolicidal agent is usually injected into the cyst before surgery to prevent secondary cyst formation in case of cyst rupture. Due to the side effects of chemical protoscolicidal agents attempts have been focused on herbal medicine. In this regard, Allium sativum has already been used; however, the protoscolicidal effect of Allium hirtifolium from Allium family has not been investigated, so far.

OBJECTIVE

The present study was conducted in order to assess the protoscolicidal effect of methanolic extract of Allium hirtifolium in different concentrations, temperature and exposure times. Cetrimide as a positive control and DMSO as a negative control were also used in this study.

METHODS

The viability of protoscoleces was determined by 0.1% eosin staining method.

RESULTS

The protoscolicidal effect of Allium hirtifolium on protoscoleces was as follows: The mean percent and standard deviation (SD) of protoscolicidal activity of 50 mg/ml concentration of Allium hirtifolium extract in room temperature at 10, 20, 30, 40 and 50 minutes of exposure was 5.88±2.39, 8.59±4.54, 11.82±5.81, 12.31±6.16and 16.96±8.42 respectively; while at 37°C it was 9.10±5.01, 11.52±7.36, 18.64±4.36, 27.07±6.57 and 38.15±12.80, respectively.

CONCLUSION

In conclusion, although Allium hirtifolium from Allium family is similar to Allium sativum; the protoscolicidal effect of its methanolic extract is not similar and less than A. sativum extract.

Protoscolicidal Effects of the Garlic Chloroformic Extract on the Protoscolices of Hydatid Cyst at a Short Exposure Time, up to Five Minutes

BACKGROUND

The treatment of choice for hydatidosis as an important zoonotic disease is surgery. Different agents are injected into the cyst to prevent secondary hydatidosis. To avoid the side effects of such protoscolicidal agents, considering the high protoscolicidal effects of the garlic extract, we conducted the present study on protoscolices in limited applicable times and compared the extract with some chemical agents.

METHODS

Sheep's liver and lung cysts were collected. Ninety tubes were selected and divided into 3 sets (for different exposure times), each one comprising 5 groups of 6 tubes. Each tube contained 3000-4000 protoscolices. The groups were 0.5% cetrimide (as positive control), 20% hypertonic sodium chloride, 0.5% silver nitrate, 0.9% normal saline (as negative control), and the garlic chloroformic extract (200 mg/mL). The viability of the protoscolices was assessed using 0.1% eosin. The ANOVA and LSD were used to compare the mean viability of the protoscolices after exposure to the different agents at different times and concentrations. The data were analyzed using SPSS software, version 17. A P<0.05 was considered significant.

RESULTS

Our findings showed that the protoscolicidal effects of the garlic extract at 1 (P<0.001) and 2 (P<0.001 and P=0.003) minutes of exposure were higher than those of sodium chloride and silver nitrate. At 5 minutes of exposure, there was no difference between the garlic extract and sodium chloride (P=0.36); however, the difference between these agents and silver nitrate was significant.

CONCLUSION

The garlic chloroformic extract in a short exposure time had high protoscolicidal effects and could substitute other agents.

Progress in the pharmacological treatment of human cystic and alveolar echinococcosis: Compounds and therapeutic targets

Human cystic and alveolar echinococcosis are helmintic zoonotic diseases caused by infections with the larval stages of the cestode parasites Echinococcus granulosus and E. multilocularis, respectively. Both diseases are progressive and chronic, and often fatal if left unattended for E. multilocularis. As a treatment approach, chemotherapy against these orphan and neglected diseases has been available for more than 40 years. However, drug options were limited to the benzimidazoles albendazole and mebendazole, the only chemical compounds currently licensed for treatment in humans. To compensate this therapeutic shortfall, new treatment alternatives are urgently needed, including the identification, development, and assessment of novel compound classes and drug targets. Here is presented a thorough overview of the range of compounds that have been tested against E. granulosus and E. multilocularis in recent years, including in vitro and in vivo data on their mode of action, dosage, administration regimen, therapeutic outcomes, and associated clinical symptoms. Drugs covered included albendazole, mebendazole, and other members of the benzimidazole family and their derivatives, including improved formulations and combined therapies with other biocidal agents. Chemically synthetized molecules previously known to be effective against other infectious and non-infectious conditions such as anti-virals, antibiotics, anti-parasites, anti-mycotics, and anti-neoplastics are addressed. In view of their increasing relevance, natural occurring compounds derived from plant and fungal extracts are also discussed. Special attention has been paid to the recent application of genomic science on drug discovery and clinical medicine, particularly through the identification of small inhibitor molecules tackling key metabolic enzymes or signalling pathways.

Human cystic and alveolar echinococcosis (CE and AE), caused by the larval stages of the helminths Echinococcus granulosus and E. multilocularis, respectively, are progressive and chronic diseases affecting more than 1 million people worldwide. Both are considered orphan and neglected diseases by the World Health Organization. As a treatment approach, chemotherapy is limited to the use of benzimidazoles, drugs that stop parasite growth but do not kill the parasite. To compensate this therapeutic shortfall, new treatment alternatives are urgently needed. Here, we present the state-of-the-art regarding the alternative compounds and new formulations of benzimidazoles assayed against these diseases until now. Some of these new and modified compounds, either alone or in combination, could represent a step forward in the treatment of CE and AE. Unfortunately, few compounds have reached clinical trials stage in humans and, when assayed, the design of these studies has not allowed evidence-based conclusions. Thus, there is still an urgent need for defining new compounds or improved formulations of those already assayed, and also for a careful design of clinical protocols that could lead to the draw of a broad international consensus on the use of a defined drug, or a combination of drugs, for the effective treatment of CE and AE.

Solidification of hydatid cyst fluid with an injectable chitosan/carboxymethylcellulose/β-glycerophosphate hydrogel for effective control of spillage during aspiration of hydatid cysts

Cystic echinococcosis (CE)/hydatid cyst is one of the most important helminthic diseases in the world. The treatment of hydatid cyst ranges from surgical intervention to chemotherapy, although the efficacy of chemotherapy is still unclear. Postoperative complication which results from the spillage of cysts during surgical operation is one of the most important concerns in surgical treatment of hydatid cyst. The aim of the current study was to solidify the hydatid cyst fluid (HCF) with an injectable and thermosensitive chitosan (CS)/carboxymethyl cellulose (CMC)/β-glycerol phosphate (BGP) hydrogel for effective control of spillage during the aspiration of hydatid cysts. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), water uptake, rheological analysis, and Alamar Blue cytotoxicity assay were employed to characterize the hydrogel. A five level with three times replication at the central point using a central composite design (CCD), which is a response surface methodology (RSM), was used to optimize the experimental conditions. Assessment of the produced hydrogel showed that the intermolecular interactions of amino groups of chitosan and hydrogen groups of CMC were correctively established and appreciable swelling with a good strength was obtained. Hydrogels morphology had a porous structure. Rheological analysis showed that CS/CMC/BGP blends had a phase transition (32-35 °C) of sol-gel close to the body temperature. Alamar Blue cytotoxicity assay showed that CS (1.75%)/CMC (1.4%)/BGP (2.9%) had IC50 values of 0.598, 0.235 and 0.138 (µg/µL) for 24, 48 and 72 h, which indicated that the produced polymer solution had no significant cytotoxic effect for human fibroblast cell line. In vitro injection of the polymer solution of CS/CMC/BGP with CS/CMC ratio of 1.75/1.4 was done on HCF (1 mL polymer solution to 3 mL of HCF) at 37 °C with a final concentration of 2.9% for BGP resulting in solidification of HCF in less than 45 min.

Scolicidal agents for protoscolices of Echinococcus granulosus hydatid cyst: Review of literature

Hydatid cyst is the larval stage of dog tape worm Echinococcus granulosus. Protoscolices are parasite larvae that develop into adult worms in the final host intestine. During surgical treatment of human hydatidsosis spillage of live protoscolices is the major cause of hydatidosis recurrence. To prevent this problem scolicidal agent such as hypertonic salt are used to kill the protoscolices that may disseminate into the patient's tissues during surgery. However, they may have some unacceptable side effects. To find scolicidal agents with high efficacy, the effect of different compounds on protoscolices of hydatid cyst in vitro has been reviewed. Using PubMed, Scopus, Google Scholar, and SID databases articles about scolicidal effects of different agents on protoscolices of hydatid cyst in vitro were collected. Foeniculum vulgare after 5 min, metalonic extracts of Allium sativum and hypertonic saline after 10 min, and warm water after 2 min kill all alive protoscolices. The above agents that in minimum time and minimum concentration have 100% scolicidal activity, could be good candidates for further investigations.

Effects of trigonelline inhibition of the Nrf2 transcription factor in vitro on Echinococcus granulosus

The aim of this study was to investigate the impact of trigonelline (TRG) on Echinococcus granulosus, and to explore the inhibition impact of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway on E. granulosus protoscoleces. Echinococcus granulosus protoscoleces were incubated with various concentrations of TRG, and then Nrf2 protein expression and its localization in protoscoleces were detected by western blot analysis and immunofluorescence assay, respectively. Reactive oxygen species (ROS) level in protoscoleces was measured using ROS detection kit. Caspase-3 activity was measured using a caspase-3 activity assay kit, and NAD(P)H quinone oxidoreductase (NQO)-1 and heme oxygenase (HO)-1 activities in protoscoleces were measured by ELISA. The effect of TRG on protoscoleces viability was investigated using 0.1% eosin staining, and ultrastructural alterations in protoscoleces were examined by scanning electron microscopy (SEM). Immunolocalization experiment clearly showed that Nrf2 protein was predominantly present in cells of protoscoleces. TRG treatment reduced NQO-1 and HO-1 activities in protoscoleces, but could increase ROS level at early time. Protoscoleces could not survive when treated with 250 μM TRG for 12 days. SEM results showed that TRG-treated protoscoleces presented damage in the protoscoleces region, including hook deformation, lesions, and digitiform protuberance. Nrf2 protein expression was significantly decreased and caspase-3 activity was clearly increased in protoscoleces treated with TRG for 24 and 48 h, respectively, when compared with that in controls (P < 0.05). Our results demonstrated that TRG had scolicidal activity against E. granulosus protoscoleces. Nrf2 protein was mainly expressed in the cells and TRG could efficiently inhibit the Nrf2 signaling pathway in E. granulosus.

Chemical composition, efficacy and safety of Pistacia vera (var. Fandoghi) to inactivate protoscoleces during hydatid cyst surgery

At present, various scolicidal agents have been used for inactivation of protoscoleces during hydatid cyst surgery, however, they are associated with serious adverse side effects including sclerosing colangititis (biliary tract fibrosis), liver necrosis and methaemoglobinaemia. This investigation was designed to evaluate the chemical composition and in vitro scolicidal effects of Pistacia vera (var. Fandoghi) essential oil against protoscoleces of hydatid cysts and also its toxicity in mice model. The components of the P. vera essential oil were identified by gas chromatography/mass spectroscopy (GC/MS) analysis. Protoscoleces were aseptically aspirated from sheep livers having hydatid cysts. Various concentrations of the essential oil (25-200μl/mL) were used for 5-30min. Viability of protoscoleces was confirmed using eosin exclusion test (0.1% eosin staining). In addition, forty male NIH mice were used to determine the acute and sub-acute toxicity of P. vera essential oil for 2 and 14 days, respectively. The main components of P. vera essential oil were limonene (26.21%), α-pinene (18.07%), α-thujene (9.31%) and α-terpinolene (9.28%). Findings of the present study demonstrated that the P. vera essential oil at the concentrations of 100 and 200μl/mL killed 100% protoscoleces after 10 and 5min of exposure, respectively. The LD50 values of intraperitoneal injection of the P. vera essential oil was 2.69ml/kg body weight, and the maximum nonfatal doses were 1.94ml/kg body weight. No significant difference (P>0.05) was observed in the clinical chemistry and hematological parameters following oral administrations of P. vera essential oil at the doses 0.1, 0.2, and 0.4ml/kg for 14 days. The obtained findings demonstrated new chemical composition and promising scolicidal activity of the P. vera with no significant toxicity which might be used as a natural scolicidal agent in hydatid cyst surgery.

Comparison of Scolicidal Effects of Amphotricin B, Silver Nanoparticles,_and Foeniculum vulgare Mill on Hydatid Cysts Protoscoleces

BACKGROUND

Surgery is the preferred treatment for hydatid cyst (cystic echinococcosis, CE). At present, various scolicidal agents have been used for inactivation of protoscoleces during surgery, but they are associated with adverse side effects. The aim of the present study was to evaluate the scolicidal effects of amphotricin B, Silver nano particles, Foeniculum vulgare Mill, essential oil and hypertonic saline against protoscoleces of hydatid cyst on an in vitro model.

METHODS

Protoscoleces were aseptically aspirated from the naturally infected livers of sheep and goats. Various concentrations of AmB (2.5-20 mg/ml), Ag-NPs (0.5-4 mg/ml), F. vulgare essential oil (0.125-1 mg/ml) and hypertonic saline (10-20%) were used for 5-60 min. Eosin exclusion test was used to determine the viability of protoscoleces.

RESULTS

Maximum protoscolicidal effect of AmB and Ag-NPs was found at concentrations of 20 and 4 mg/mL, resulting in only 82.3% and 71.6% of the protoscoleces after 60 min of incubation, respectively. In contrast, F. vulgare essential oil at concentration of 1 mg/ml and hypertonic saline 20% killed 100% protoscoleces after 5 and 10 min of exposure, respectively.

CONCLUSION

The results indicated weak scolicidal activity of AmB and Ag-NPs; whereas F. vulgare essential oil had potent scolicidal activity against protoscoleces of hydatid cyst that revealed the potential of F. vulgare as a natural source for the production of new scolicidal agent for use in hydatid cyst surgery. However, further studies will be needed to confirm these results by checking the essential oil and its active component in the in vivo model.

Scolicidal effects of black cumin seed (Nigella sativa) essential oil on hydatid cysts

Surgery remains the preferred treatment for hydatid cyst (cystic echinococcosis, CE). Various scolicidal agents have been used for inactivation of protoscolices during surgery, but most of them are associated with adverse side effects. The present study aimed to evaluate the in vitro scolicidal effect of Nigella sativa (Ranunculaceae) essential oil and also its active principle, thymoquinone, against protoscolices of hydatid cysts. Protoscolices were aseptically aspirated from sheep livers having hydatid cysts. Various concentrations of the essential oil (0.01-10 mg/ml) and thymoquinone (0.125-1.0 mg/ml) were used for 5 to 60 min. Viability of protoscolices was confirmed by 0.1% eosin staining. Furthermore, the components of the N. sativa essential oil were identified by gas chromatography/mass spectroscopy (GC/MS). Our study revealed that the essential oil of N. sativa at the concentration of 10 mg/ml and its main component, thymoquinone, at the concentration of 1 mg/ml had potent scolicidal activities against protoscolices of Echinococcus granulosus after 10 min exposure. Moreover, thymoquinone (42.4%), p-cymene (14.1%), carvacrol (10.3%), and longifolene (6.1%) were found to be the major components of N. sativa essential oil by GC/MS analysis. The results of this study indicated the potential of N. sativa as a natural source for production of a new scolicidal agent for use in hydatid cyst surgery. However, further studies will be needed to confirm these results by checking the essential oil and its active component in in vivo models.

In vitro lethal effects of various extracts of Nigella sativa seed on hydatid cyst protoscoleces

OBJECTIVES

There are several scolicidal agents for inactivation of hydatid cyst protoscolices during surgery, but most of them are associated with adverse side effects such as sclerosing cholangitis and liver necrosis. The present study was aimed to evaluate scolicidal effects of various extracts of Nigella sativa seeds against protoscoleces of hydatid cyst in an in vitro model.

MATERIALS AND METHODS

Protoscoleces were aseptically aspirated from naturally infected livers of sheep and goats. Various concentrations of the different extracts of N. sativa (5 to 50 mg/ml) were used for 5 to 60 min. Viability of protoscoleces was confirmed by 0.1% eosin staining.

RESULTS

The findings exhibited that methanolic extract at the concentration of 50 mg/ml after 10 min of incubation, and aqueous extract at the concentration of 50 mg/ml after 30 min of incubation can kill 100% of protoscoleces. In addition, all of experiments revealed dose-dependent and also time-dependent scolicidal effect of various extracts of N. sativa on the protoscoleces of hydatid cyst.

CONCLUSION

The results of the present study demonstrated that N. sativa may be a natural source for the production of new scolicidal agent for use in hydatid cyst surgery. However, further studies will be required to evaluate scolicidal effects of N. sativa in the in vivo model.

Scolicidal effects of biogenic selenium nanoparticles against protoscolices of hydatid cysts

Cystic echinococcosis (hydatid cyst, CE) as a zoonotic parasitic infection caused by the larval stage of the dog tapeworm Echinococcus granulosus is still an important economic and public health concern in the world. One of the treatment options for CE is surgical removal of the cysts combined with chemotherapy using albendazole and/or mebendazole before and after surgery. Currently, many scolicidal agents, which have some complications, have been used for inactivation of the cyst contents. Therefore the development of new scolicidal agents with low side effects and more efficacies is an urgent need for surgeons. The present study was aimed to investigate the in vitro scolicidal effect of selenium nanoparticles biosynthesized by a newly isolated marine bacterial strain Bacillus sp. MSh-1 against protoscoleces of E. granulosus. Protoscolices were aseptically aspirated from sheep livers having hydatid cysts. Various concentrations (50-500 μg/ml) of Se NPs (in size range of about 80-220 nm) were used for 10-60 min. Viability of protoscoleces was confirmed by 0.1% eosin staining. The results indicated that biogenic Se NPs at all concentrations have potent scolicidal effects especially at concentrations 500 and 250 μg/ml after 10 and 20 min of application, respectively. In conclusion, the findings of present study proven that Se NPs have potent scolicidal effects, therefore may be used in CE surgery. However, the in vivo efficacy of these NPs remains to be explored.

Study of Protoscolicidal Effects of Hypertonic Glucose on Protoscolices of Hydatid Cyst at Different Concentrations and Exposure Times

Surgical operation is the treatment of choice for hydatid cyst. To date, many protoscolicidal substances have been used for inactivation of hydatid cyst contents but most of these compounds may produce several side effects. The aim of this study was to evaluate the protoscolicidal effects of hypertonic glucose on protoscolices of hydatid cyst at different concentrations and exposure times. Protoscolices were obtained aseptically from the livers of slaughtered sheep at Qazvin abattoir, Iran. Protoscolices were exposed to different concentrations of hypertonic glucose (10%, 15%, 20%, 25%, 30%, 40%, and 50%) at different times (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, and 60 min). Viability of protoscolices was evaluated by 0.1% eosin and the movement of protoscolices flame cells. The highest protoscolicidal effect (100%) of hypertonic glucose was obtained at concentrations 40% and 50% following 40 and 20 min exposure times, respectively. Some protoscolicidal agents show a variety of dangerous complications such as biliary tract fibrosis and liver necrosis; however, hypertonic glucose especially at a concentration of 40% may demonstrate less side effects compared with glucose 50%. Further in vivo investigations are suggested.

In vitro protoscolicidal effects of high-intensity focused ultrasound enhanced by a superabsorbent polymer

Echinococcus granulosus, the etiologic agent of cystic echinococcosis in humans and other animal hosts, is distributed worldwide. Echinococcosis is an increasing public health and socioeconomic concern. The present work evaluated whether or not a superabsorbent polymer (SAP) could enhance the damage efficacy of high-intensity focused ultrasound (HIFU) on the viability of E. granulosus protoscolices in vitro. HIFU of 100 W acoustic power and 0.01 g superabsorbent polymer were used to treat 5,000 protoscolices in 2-ml protoscolices suspension. After different HIFU exposure time (5, 10, 20, 30, 40, 50, and 60 s, respectively), the temperature of protoscolices suspension was taken, and the treated protoscolices were stained by trypan-blue exclusion assay, and their structures were observed by light microscopy. To better understand the biological mechanisms responsible for the deaths of protoscolices, the activity of succinate dehydrogenase (SDH) of the protoscolices treated with HIFU was examined. The temperature of protoscolices suspension treated with HIFU rose slowly, and the death rate of protoscolices was 73.7 % in the group of HIFU treatment time of 40 s; however, with the same HIFU treatment time of 40 s, the temperature of protoscolices suspension in the group of HIFU combined with SAP rose quickly, and the death rate of protoscolices was 100 %. The same protoscolicidal effect (100 %) of HIFU of 100 W acoustic power combined with SAP was also observed in the groups of HIFU treatment time of 50 and 60 s, respectively. The dead protoscolices were stained to blue, shrunken and black calcareous corpuscles, and disordered and decreasing hooks though of intact membrane, as well as some protoscolices lost hooks and tore open on membrane were observed. In the group of HIFU combined with SAP, it was found that the superabsorbent polymer was surrounded by the spoiled, and the destruction of protoscolices was much stronger than in the group of HIFU. The dead protoscolices exhibited the reduction or absence of SDH staining intensity in the parenchymal cell and calcareous corpuscles after HIFU irradiation, where a large number of necrotic cells were evident. These results suggested that HIFU could induce the damage and loss of viability of protoscolices; SAP could enhance the HIFU energy focused and cause more severe destruction efficacy on protoscolices; and mitochondrial energetic function is involved in the regulation of cell-death pathways of protoscolices.

Scolicidal effects of Olea europaea and Satureja khuzestanica extracts on protoscolices of hydatid cysts

Treatment of hydatid disease is mainly surgical, with medical treatment being reserved as a coadjuvant treatment. Use of effective scolicidal agents during surgery of cystic echinococcosis is essential to reduce the recurrence rate. The goal of this study was to evaluate the in vitro scolicidal effects of hydroalcoholic extracts of Satureja khuzestanica leaves and aqueous extracts of Olea europaea leaves on hydatid cyst protoscolices. Echinococcus granulosus protoscolices were collected from the liver of sheep infected with the hydatid cyst. Various concentrations of plant extracts were used in different exposure times for viability assay of protoscolices. Among the olive leaf extracts tested, 0.1% and 0.01% concentrations had strong scolicidal effects in 120 min. S. khuzestanica 0.1% had very strong scolicidal effects in 30, 60, and 120 min of exposure times and the mortality rate decreased with the lower concentration. The finding have shown that the scolicidal activity of S. khuzestanica against cystic echinococosis protoscolices were more effective, while the O. europaea extract showed less effects.

Evaluation of different chemical agents on the germinative layer of sheep hydatid cyst after implantation to peritoneal cavity of BALB/c

In spite of the use of protoscolocidal agents during hydatid cyst surgery, a notable rate of disease recurrence in postoperation patients is still observed. The question remains whether living protoscolices lead to recurrence or the recurrence is due to the remainder of the germinative layer in the peritoneal cavity. The aim of this study was in vivo evaluation of different chemical (protoscolicidal) solutions on the germinative layer of the hydatid cyst. The germinative layer of sheep hydatid cyst was separated under sterile condition, divided into 0.25-cm(2) parts, and exposed to 0.5% cetrimide, 0.5% silver nitrate, 20% hypertonic saline, 15% dextrose and 25% dextrose, and normal saline as negative control for 2 min. The exposed germinative layers were implanted into the peritoneal cavity of 90 Balb/C mice (15 mice in each group). After nine months, the peritoneum was evaluated macroscopically as well as microscopically for the presence of any hydatid cyst. No hydatid cyst was observed in the peritoneal cavity of the exposed mice. The role of the germinative layer for inducing hydatid cysts in mice is questionable. However, the present study showed that the germinative layer had no role in the induction of hydatid cyst in these laboratory animals.

Echinococcus granulosus: protoscolicidal effect of high intensity focused ultrasound

High intensity focused ultrasound (HIFU) is a new non-invasive technique which can cause cell death and tissue necrosis by focusing high-energy ultrasonic waves on a single location. The aim of our work is to investigate the damaging effect of HIFU on Echinococcus granulosus protoscolices, as well as its inhibitory effect on growth of hydatid cysts derived from protoscolices. The damaging effect of HIFU on protoscolices was investigated by following parasite mortality after irradiation, while the inhibitory effect was investigated by infection experiments in vivo. The results demonstrated that HIFU was able to damage protoscolices and the protoscolicidal effect was dose-dependent and showed late-onset. The growth of protoscolices that survived the exposure to HIFU was obviously suppressed in vitro, and the mean weight of hydatid cysts resulting from such protoscolices in the experimental group was less than that in controls. Evidences including the protoscolicidal effect, fragmentized protoscolices and low post exposure temperatures, suggest that cavitation may contribute to the protoscolicidal effect of HIFU. In addition, the structure of the germinal membrane in cysts developing from the irradiated protoscolices was not as normal or intact as that from non-irradiated ones, and morphological changes related to degeneration were observed, suggesting that HIFU could prevent protoscolices from developing normal germinal membrane and consequently stop the proliferation of secondary hydatid cysts. HIFU demonstrated damaging effect on protoscolices, inhibited the growth of protoscolices in vitro and in vivo, and could be a possible therapeutic option for cystic echinococcosis.