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

An in vivo appraisal of Punica granatum peel extract's ultrastructural effect on cystic echinococcosis in mice

In the past decade, interest has significantly increased regarding the medicinal and nutritional benefits of pomegranate (Punica granatum) peel. This study examined the effects of using pomegranate peel extract (PGE) alone and in combination with albendazole (ABZ) on ultrastructural and immunological changes in cystic echinococcosis in laboratory-infected mice. Results revealed that the smallest hydatid cyst size and weight (0.48 ± 0.47mm, 0.17 ± 0.18 gm) with the highest drug efficacy (56.2%) was detected in the PGE + ABZ group, which also exhibited marked histopathological improvement. Ultrastructural changes recorded by transmission electron microscopy including fragmentation of the nucleus, glycogen depletion, and multiple lysosomes in vacuolated cytoplasm were more often observed in PGE + ABZ group. IFN-γ levels were significantly increased in the group treated with ABZ, with a notable reduction following PGE treatment, whether administered alone or in combination with ABZ. Thus, PGE enhanced the therapeutic efficiency of ABZ, with improvement in histopathological and ultrastructural changes.

Metabolic mechanism and pharmacological study of albendazole in secondary hepatic alveolar echinococcosis (HAE) model rats

Albendazole (ABZ) is the primary treatment for alveolar echinococcosis (AE); however, its limited solubility impacts oral bioavailability, affecting therapeutic outcomes. In this study, various ABZ-solubilizing formulations, including albendazole crystal dispersion system (ABZ-CSD), albendazole hydrochloride-hydroxypropyl methylcellulose phthalate composite (TABZ-HCl-H), and albendazole hydroxyethyl sulfonate-hydroxypropyl methylcellulose phthalate composite (TABZ-HES-H), were developed and evaluated. Physicochemical properties as well as liver enzyme activity were analyzed and their pharmacodynamics in an anti-secondary hepatic alveolar echinococcosis (HAE) rat model were investigated. The formulations demonstrated improved solubility, exhibiting enhanced inhibitory effects on microcysts in HAE model rats compared to albendazole tablets. However, altered hepatic drug-metabolizing enzymes in HAE model rats led to increased ABZ levels and reduced ABZ-SO production, potentially elevating drug toxicity. These findings emphasize the importance of dose adjustments in patient administration, considering the impact of alveolar echinococcosis on rat hepatic drug metabolism.

Investigation of patients with new infection of echinococcal cyst in Sardinia, Italy

Cystic Echinococcosis (CE) is a zoonotic disease caused by the larval stage of a tapeworm of Taeniidae family, genus Echinococcus and species Echinococcus granulosus sensu lato (s.l.). CE is a worldwide public health problem and is highly incident in all Mediterranean areas. Following clinical, image techniques and serological investigations all 83 subjects involved in the study were diagnosed for CE. General and clinical data were entered into a database and evaluated. The 43.37% were female and 56.63% male, mean age was 50.71 while the range most represented (22.7%) was between 61->70 years. The purposes of our survey were to investigate these 83 patients enrolled in the study and to deeply examine 20 (24.10%) patients that developed a new echinococcal cyst. Moreover, the causes at the basis of the onset of a new cyst were analysed, together with a possible correlation with different treatments related to primary infection corresponding to surgery (n=7), albendazole (n=6), PAIR (n=3) and watch and wait (n=4). A possible link with medical treatments of the primary infection was observed in the subjects who underwent surgery or PAIR and a likely correlation attributable to high environmental contamination in subjects managed with drugs or watch and wait was detected. Moreover, our analysis evidenced that patients with a new infection presented a more severe diagnosis along with a major mortality rate. Finally, these data may have an important contribution for an epidemiological point of view concerning the percentage of CE in a specific geographical endemic area, such as Sardinia.

Therapeutic effect of curcumin nanoemulsion on cystic echinococcosis in BALB/c mice: a computerized tomography (CT) scan and histopathologic study evaluation

BACKGROUND

This study aimed to determine the therapeutic efficacy of curcumin nanoemulsion (CUR-NE) in mice infected with Echinococcus granulosus sensu stricto protoscoleces.

METHODS

Forty-two inbred BALB/c mice were divided into seven groups of six animals each. Six groups were inoculated intra-peritoneally with 1500 viable E. granulosus protoscoleces, followed for six months and used as infected groups. The infected groups were named as: CEI1 to CEI6 accordingly. The 7th group was not inoculated and was named cystic echinococcosis noninfected group (CENI7). CEI1 and CEI2 groups received 40 mg/kg/day and 20 mg/kg/day curcumin nanoemulsion (CUR-NE), respectively. CEI3 received nanoemulsion without curcumin (NE-no CUR), CEI4 received curcumin suspension (CUR-S) 40 mg/kg/day, CEI5 received albendazole 150 mg/kg/day and CEI6 received sterile phosphate-buffered saline (PBS). CENI7 group received CUR-NE 40 mg/kg/day. Drugs administration was started after six months post-inoculations of protoscoleces and continued for 60 days in all groups. The secondary CE cyst area was evaluated by computed tomography (CT) scan for each mouse before treatment and on the days 30 and 60 post-treatment. The CT scan measurement results were compared before and after treatment. After the euthanasia of the mice on the 60th day, the cyst area was also measured after autopsy and, the histopathological changes of the secondary cysts for each group were observed. The therapeutic efficacy of CUR-NE in infected groups was evaluated by two methods: CT scan and autopsied cyst measurements.

RESULTS

Septal calcification in three groups of infected mice (CEI1, CEI2, and CEI4) was revealed by CT scan. The therapeutic efficacy of CUR-NE 40 mg/kg/day (CEI1 group) was 24.6 ± 26.89% by CT scan measurement and 55.16 ± 32.37% by autopsied cysts measurements. The extensive destructive effects of CUR-NE 40 mg/kg/day (CEI1 group) on the wall layers of secondary CE cysts were confirmed by histopathology.

CONCLUSION

The current study demonstrated a significant therapeutic effect of CUR-NE (40 mg/kg/day) on secondary CE cysts in BALB/c mice. An apparent septal calcification of several cysts revealed by CT scan and the destructive effect on CE cysts observed in histopathology are two critical key factors that suggest curcumin nanoemulsion could be a potential treatment for cystic echinococcosis.

Evaluation of the Protoscolicidal Activity of Humulus lupulus Methanolic Extracts on Echinococcus granulosus Sensu Stricto

The larval stage of the parasite Echinococcus granulosus sensu lato (s.l) is responsible for cystic echinococcosis (CE), a long-term infection affecting humans and animals worldwide, and constitutes a serious public health concern. If left untreated, CE can cause serious damage to multiple organs, especially the liver and lungs. Regarding the treatment, in the last few years, the use of pharmacological treatment has increased, suggesting that in the future, drug therapy may replace surgery for uncomplicated cysts. However, the only available anthelmintic drug to treat this infection is the albendazole, which has an efficacy that does not exceed 50%. On the basis of the above-mentioned evidence, new and improved alternative treatments are urgently needed. The use of natural products and their active fractions and components holds great promise as a valuable resource for the development of novel and effective therapies. Hop (Humulus lupulus L.) is a bittering agent in the brewing industry for which the sedative, digestive, anti-inflammatory, and antimicrobial effects have been reported. The purpose of this study was to assess the in vitro efficacy of methanolic extracts from the leaves of hop varieties against E. granulosus sensu stricto (s.s) protoscoleces. Varieties Mapuche and Victoria caused a stronger protoscolicidal effect compared to the Bullion, Cascade, and Traful varieties (P < 0.01), coinciding with their highest content of flavonoids, total polyphenols, and saponins. The viability of protoscoleces treated with the varieties Mapuche and Victoria decreased to approximately 50% at days 5 y 8, respectively, showing alterations such as soma contraction and impaired microtriches. After 18 days of treatment with both varieties, protoscoleces were completely altered both structurally and ultrastructurally. In conclusion, the methanolic extracts of the H. lupulus varieties Mapuche and Victoria demonstrated a marked in vitro effect against E. granulosus s.s. protoscoleces. The beer-making industry exclusively uses hop cones, leaving behind large amounts of hop leaves as an agricultural by-product that is not being utilized. On the basis of our study, we propose that hop leaves could also be used as a source of secondary metabolites with anthelmintic activity.

Specialized Laparoscopic Devices in the Treatment of Hydatic Hepatic Cysts: A Retrospective Analysis and Review of the Literature

Background and objective While hydatid disease is associated with a high prevalence only in certain endemic areas, it can be encountered in any geographical region. The characteristics of this parasitic disease, and its implications during development, such as the risk of seeding, and the complications caused by cyst rupture, means that its therapeutic management should adhere to strict principles and may sometimes require approaches specially tailed for this type of pathology. In this study, we aimed to provide a comparative analysis of conventional laparoscopic techniques vs. treatment with specialized instrumentation in these patients. Methods Our study involved a retrospective evaluation of a cohort comprising 41 patients diagnosed with hepatic hydatid cysts, who underwent procedures with both conventional laparoscopic techniques and specialized instrumentation tailored for this particular pathology. Furthermore, we conducted a comprehensive review of the literature examining alternative types of laparoscopic instrumentation specifically crafted for the management of hydatid cysts. This review employed an extensive search utilizing PubMed and Google Scholar databases. Results The examination of cases within our study revealed a high prevalence of hydatid disease among male patients (63.41%) and a predominance of instances originating from rural regions necessitating emergent admissions (p<0.05). Notably, in 58.54% of cases, surgical interventions employed specialized instrumentation, with a notable discrepancy in conversion rates to open surgery favoring the standard approach: 12.2% vs. 2.44% (p=0.025). Additionally, the laparoscopic approach was associated with prolonged surgical durations compared to the dedicated technique (p=0.002), besides a higher incidence of postoperative complications (12.2% vs 7.32%). Furthermore, patients undergoing laparoscopic procedures with standard instrumentation experienced lengthier hospital stays (p=0.002). Our comprehensive review of the literature identified six distinct surgical methodologies utilizing specifically tailored instrumentation for addressing hydatid cysts. Analysis of these findings underscored a preference for single localizations and selective cases. Postoperative complication rates ranged from 6.66% to 22.22%, with conversion rates to open surgery reaching up to 23.33%, and recurrence rates observed to be as high as 7.81%. Conclusions The patented approach, which uses special trocars that provide stable anchorage and allow a safe puncture-aspiration, reaspiration, and fragmentation processes, has superior characteristics compared to the laparoscopic approach with standard instrumentation. Comparative analysis with other similar procedures described in the literature has shown similar results regarding the frequency of complications, with our technique being superior in terms of approaching multiple cysts and recurrence rate. It has been successfully applied even in unselected cases.

Laparoscopic Management of Multiple Liver, Omental, Mesenteric, Peritoneal, and Round Ligament Hydatid Cysts-A Rare Report of a Case and a Systematic Literature Review

Hydatid cyst disease is a parasitic ailment with an endemic nature, predominantly affecting geographical areas with a tradition in animal husbandry. The most common localization of hydatid disease is in the liver (60%), followed by the lungs, with other organ localizations comprising less than 10%. The surgical approach to this condition can be carried out through open surgery or laparoscopy. The coexistence of hepatic and intraperitoneal hydatidosis often leads to the preference for open surgery. We performed a literature review aiming to retrieve data regarding demographic characteristics, clinical features, preoperative management, and surgical approach concerning these unusual localizations of hydatid disease. It was observed that the mesenteric localization frequently presented with acute abdominal pain (p = 0.038) and that the open approach was preferred in 85.71% of cases. Furthermore, an interdependence was identified between the localization of the cysts and the type of surgical approach (p = 0.001), with mesenteric localizations being approached through laparotomy and excision (p = 0.037), while omental localizations, due to the easier approach, benefited from laparoscopy with excision in 14.29% of cases. Overall, the laparoscopic approach was less frequently used, but its utilization resulted in a lower number of complications and faster recovery. Additionally, we present a rare case of hepatic and intra-abdominal hydatidosis, resolved exclusively through a laparoscopic approach, including a review of the literature for these uncommon localizations of hydatid disease. A 45-year-old patient diagnosed with multiple hydatid cysts, both hepatic and intraperitoneal, underwent surgical intervention with exploratory laparoscopy. Laparoscopic excision of peritoneal, epiploic, mesenteric cysts, and round ligament, along with laparoscopic inactivation, evacuation, and pericystectomy of hepatic hydatid cysts, was performed. The patient's recovery was uneventful, and she was reevaluated at 3 and 9 months without signs of recurrence. The association of hepatic hydatid cysts with multiple intra-abdominal localizations is not commonly encountered. The treatment of choice is surgical and is predominantly conducted through open surgery. The presented case is unique due to the exclusive laparoscopic approach in the management of mixed hepatic and intra-abdominal hydatidosis.

Cystic Echinococcosis in the Early 2020s: A Review

Cystic echinococcosis (CE) is a zoonosis caused by metacestodes, the larval stage of Echinococcus granulosus. Although the World Health Organization (WHO) has defined CE as a neglected disease, it is the second most important foodborne parasitic disease, and it remains an important public health issue, considering its zonal endemicity and potential morbidity. The control and prevention of CE is a relevant WHO target, especially from a One Health perspective, as the disease affects not only animals and humans but also the food chain. Since not all countries have a CE surveillance strategy or reporting system and specific management guidelines, recent epidemiological data are relatively scarce, and research concerning the specific geographical distribution of the disease is ongoing. To add new information to the subject, we have analyzed and collected data from national guidelines and several medical databases. Out of the 751 research articles that were originally identified, only 52 were included in the investigation after applying specific inclusion and exclusion criteria. Notable international projects that have provided significant contributions and had a positive impact are presented. The available data were correlated with WHO recommendations on the subject, thus showcasing the measures taken and those that are still needed to properly control the disease's spread.

Ribonucleotide reductase as a therapeutic target for drug repurposing as anthelmintics

Visceral cestodiases, like echinococcoses and cysticercoses, are zoonoses of worldwide distribution and are responsible for public health problems in many countries, especially in underdeveloped regions. Current treatments have low efficiency and there are few drugs currently in use for chemotherapy, making the development of new anthelmintics an urgent matter. The nucleotide salvage pathways are the only ones available for nucleotide synthesis in cestodes and other parasitic helminths, and, here, we used in silico approaches to assess the potential of the enzymes in these pathways as targets for drug repurposing as anthelminthics. First, a genomic survey allowed to identify a repertoire of 28 enzymes of the purine and pyrimidine salvage pathways from the cestode Echinococcus granulosus sensu stricto. Regarding purines, the parasite relies on salvaging free bases rather than salvaging nucleosides. Pyrimidines, on the other hand, can be salvaged from both bases and nucleosides. Druggability of the parasite enzymes was assessed, as well as the availability of commercial inhibitors for them. Druggable enzymes were then ranked according to their potential for drug repurposing and the 17 most promising enzymes were selected for evolutionary analyses. The constructed phylogenetic trees allowed to assess the degree of conservation among ortholog enzymes from parasitic helminths and their mammalian hosts. Positive selection is absent in all assessed flatworm enzymes. A potential target enzyme for drug repurposing, ribonucleotide reductase (RNR), was selected for further assessment. RNR 3D-modelling showed structural similarities between the E. granulosus and the human orthologs suggesting that inhibitors of the human RNR should be effective against the E. granulosus enzyme. In line with that, E. granulosus protoscolices treated in vitro with the inhibitor hydroxyurea had their viability and DNA synthesis reduced. These results are consistent with nucleotide synthesis inhibition and confirm the potential of a nucleotide salvage inhibitors for repurposing as an anthelmintic.

Singab A. Botanicals against some important nematodal diseases: Ascariasis and hookworm infections

Ascariasis and intestinal parasitic nematodes are the leading cause of mass mortality infecting many people across the globe. In light of the various deleterious side effects of modern chemical-based allopathic drugs, our preferences have currently shifted towards the use of traditional plant-based drugs or botanicals for treating diseases. The defensive propensities in the botanicals against parasites have probably evolved during their co-habitation with parasites, humans and plants in nature and hence their combative interference in one another's defensive mechanisms has occurred naturally ultimately being very effective in treating diseases. This article broadly outlines the utility of plant-based compounds or botanicals prepared from various medicinal herbs that have the potential to be developed as effective therapies against the important parasites causing ascariasis and intestinal hookworm infections leading to ascariasis & infections and thereby human mortality, wherein allopathic treatments are less effective and causes enormous side-effects.

The efficiency of fabricated Ag/ZnO nanocomposite using Ruta chalepensis L. leaf extract as a potent protoscolicidal and anti-hydatid cysts agent

BACKGROUND

As a consequence of their eco-friendliness, simplicity and non-toxicity, the fabrication of metal and metal oxide nanoparticles using greener chemistry has been a highly attractive research area over the last decade.

AIM

In this study focused on the fabrication of silver-Zinc oxide nanocomposite (Ag-ZnO NCs) using Ruta chalepensis leaf extract and evaluating its potential biological activities, against Echinococcus granulosus in an in vitro and in vivo model using BALB/c mice.

METHODS

In this study, the synthesis of Ag-ZnO NCs was accomplished using local R. chalepensis leaf extracts. The synthesized nanocomposites were identified using UV-Vis, SEM-EDX, XRD, and FTIR. For a short-term assessment of acute toxicity, BALB/c mice were given the prepared NCs orally. Dual sets of mice were also intraperitoneally injected with protoscoleces for secondary echinococcosis infection. Furthermore, a blood compatibility test was carried out on the nanocomposites.

RESULTS

The synthesized Ag-ZnO NCs presented a surface plasmon peak at 329 and 422 nm. The XRD, SEM, and EDX confirmed the purity of the Ag-ZnO NCs. The FTIR spectra indicated the formation of Ag-ZnO NCs. Compared to the untreated infected mice, the treated-infected animals displayed an alteration in the appearance of the hepatic hydatid cysts from hyaline to whitish cloudy with a rough surface appearance. Lysis of RBCs at various doses of Ag-ZnONCs was significantly less than the positive contro,.

CONCLUSION

These findings revealed that the Ag-ZnO NCs didn't cause any adverse symptoms and no mortality was observed in all administered groups of mice. The obtained outcomes confirmed that concentrations of up to 40 μg/mL of the bio-fabricated Ag-ZnONCs induced no notable harm to the red blood cells.

Oral Delivery of Anti-Parasitic Agent-Loaded PLGA Nanoparticles: Enhanced Liver Targeting and Improved Therapeutic Effect on Hepatic Alveolar Echinococcosis

Background

Alveolar echinococcosis (AE) is a lethal parasitic disease caused by infection with the metacestode of the dog/fox tapeworm Echinococcus multilocularis, which primarily affects the liver. Although continued efforts have been made to find new drugs against this orphan and neglected disease, the current treatment options remain limited, with drug delivery considered a likely barrier for successful treatment.

Methods

Nanoparticles (NPs) have gained much attention in the field of drug delivery due to their potential to improve delivery efficiency and targetability. In this study, biocompatible PLGA nanoparticles encapsulating a novel carbazole aminoalcohol anti-AE agent (H1402) were prepared to promote the delivery of the parent drug to liver tissue for treating hepatic AE.

Results

H1402-loaded nanoparticles (H1402-NPs) had a uniform spherical shape and a mean particle size of 55 nm. Compound H1402 was efficiently encapsulated into PLGA NPs with a maximal encapsulation efficiency of 82.1% and drug loading content of 8.2%. An in vitro uptake assay demonstrated that H1402-NPs rapidly penetrated the in vitro cultured pre-cyst wall and extensively accumulated in the pre-cysts of E. multilocularis within only 1 h. The biodistribution profile of H1402-NPs determined through ex vivo fluorescence imaging revealed significantly enhanced liver distribution compared to unencapsulated H1402, which translated to improved therapeutic efficacy and reduced systemic toxicity (especially hepatotoxicity and cytotoxicity) in a hepatic AE murine model. Following a 30-day oral regimen (100 mg/kg/day), H1402-NPs significantly reduced the parasitic burden in both the parasite mass (liver and metacestode total weight, 8.8%) and average metacestode size (89.9%) compared to unmedicated infected mice (both p-values < 0.05); the treatment outcome was more effective than those of albendazole- and free H1402-treated individuals.

Conclusion

Our findings demonstrate the advantages of encapsulating H1402 into PLGA nanoparticles and highlight the potential of H1402-NPs as a promising liver-targeting therapeutic strategy for hepatic AE.

LncRNA Regulation Mechanism in Hepatic Alveolar Echinococcosis with Nanosecond Pulse

BACKGROUND

The mortality of patients infected with hepatic alveolar echinococcosis (HAE) was higher. The aim of this study was to investigate the therapeutic effect of nanosecond pulsed electric fields (nsPEFs) on HAE in rats and explore the related molecular mechanisms.

METHODS

Establishment of HAE rat model and the lesions were treated with nsPEFs. The RNA of lesions in the high voltage nsPEFs treatment group and model group were extracted, and lncRNA and mRNA sequence analyses was performed. After obtaining the differentially expressed lncRNAs and mRNAs between the two groups, enrichment analysis was performed for mRNAs. The target genes of lncRNAs were predicted through co-location and co-expression. The expression of important lncRNAs and target genes in lesions was detected by qPCR.

RESULTS

The HAE rat model was successfully established. After nsPEFs treatment, the size of lesions was improved significantly. Then, we identified 270 differentially expressed lncRNAs and 1659 differentially expressed mRNAs between the high voltage nsPEFs treatment group and model group. Enrichment analysis showed that the differentially expressed mRNAs were mainly enriched in metabolism and inflammation. Five important lncRNAs regulatory networks were identified, then Cpa1, Cpb1, Cel, Cela2a, and Cela3b were identified as key target genes. Importantly, the expression of 5 lncRNAs and 5 target genes was verified in the lesions.

CONCLUSIONS

Preliminary results had shown that HAE treatment with nsPEFs can inhibit the growth of lesions. NsPEFs treatment altered gene expression in the lesions, and some genes were regulated by lncRNAs. The therapeutic mechanism may involve metabolism and inflammation.

Introductory Chapter: Changes in Eco-System Change Echinococci - “One Health Concept” against Echinococci

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Killing Two Birds with One Stone: Discovery of Dual Inhibitors of Oxygen and Fumarate Respiration in Zoonotic Parasite, Echinococcus multilocularis

Ascofuranone (AF), a meroterpenoid isolated from various filamentous fungi, including Acremonium egyptiacum, has been reported as a potential lead candidate for drug development against parasites and cancer. In this study, we demonstrated that AF and its derivatives are potent anthelminthic agents, particularly against Echinococcus multilocularis, which is the causative agent of alveolar echinococcosis. We measured the inhibitory activities of AF and its derivatives on the mitochondrial aerobic and anaerobic respiratory systems of E. multilocularis larvae. Several derivatives inhibited complex II (succinate:quinone reductase [SQR]; IC₅₀ = 0.037 to 0.135 μM) and also complex I to III (NADH:cytochrome c reductase; IC₅₀ = 0.008 to 0.401 μM), but not complex I (NADH:quinone reductase), indicating that mitochondrial complexes II and III are the targets. In particular, complex II inhibition in the anaerobic pathway was notable because E. multilocularis employs NADH:fumarate reductase (fumarate respiration), in addition to NADH oxidase (oxygen respiration), resulting in complete shutdown of ATP synthesis by oxidative phosphorylation. A structure-activity relationship study of E. multilocularis complex II revealed that the functional groups of AF are essential for inhibition. Binding mode prediction of AF derivatives to complex II indicated potential hydrophobic and hydrogen bond interactions between AF derivatives and amino acid residues within the quinone binding site. Ex vivo culture assays revealed that AF derivatives progressively reduced the viability of protoscoleces under both aerobic and anaerobic conditions. These findings confirm that AF and its derivatives are the first dual inhibitors of fumarate and oxygen respiration in E. multilocularis and are potential lead compounds in the development of anti-echinococcal drugs.

Treatment of Cystic Echinococcosis in Children: A Single Center Experience

BACKGROUND

Cystic echinococcosis (CE) treatment is complicated, relying on cysts characteristics, host factors and possible treatment adverse events. We assessed childhood CE treatment characteristics.

METHODS

A retrospective cohort study, 2005-2021, which presents our experience with treating children with CE. We compared therapeutic interventions use in association with the location, size and number of cysts. Additionally, we assessed complications rate following those interventions.

RESULTS

Sixty six children had CE; 97% were Bedouins. Overall, 183 cysts were identified in 74 organs: liver (n = 47, 64%), lungs (n = 23, 31%), brain, para-ovarian, kidney and peritoneum (other-grouped, n = 4, 5%). Mean ± Standard deviation largest cyst size (per patient) was 6.6 ± 3.2 cm. Treatment with albendazole was administered to 94% of CE, while albendazole monotherapy was used in 27% (n = 18, including 4 cases with extra-hepatic cysts). Surgical interventions included drainage/puncture, aspiration, injection and reaspiration (PAIR; n = 20), mainly performed in hepatic-CE (40% vs. 4% in pulmonary-CE, and 0% in other-CE), excision and drainage (n = 34) and complete excision (n = 10), mainly done in other-CE (50% vs. 26% and 4% in pulmonary-CE and hepatic-CE, respectively). Larger cyst size was associated with complete excision compared with albendazole monotherapy. The number of cysts was not associated with the chosen intervention. Fever was recorded following 39% of surgical interventions. Local surgical complications were relatively rare.

CONCLUSIONS

Cysts location and size affected treatment choice among CE patients. Procedures with drainage had relatively higher rate of complications, including recurrence. Albendazole monotherapy may be a viable therapeutic option in selected CE cases.

Case Report: Amphotericin B and Mefloquine as a Salvage Treatment of Alveolar Echinococcosis

Alveolar echinococcosis is an emerging zoonotic disease caused by the parasite Echinococcus multilocularis. Most patients are diagnosed at a late stage, when lifelong treatment with benzimidazoles is required to stop disease progression. However, for patients who do not tolerate benzimidazole therapy, there are no alternatives. Here, we present a patient with advanced alveolar echinococcosis who was successfully treated with amphotericin B deoxycholate and mefloquine as a rescue therapy after he developed albendazole intolerance.

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.

Differential Activity of Human Leukocyte Extract on Systemic Immune Response and Cyst Growth in Mice with Echinococcus Multilocularis Infection After Oral, Subcutaneous and Intraperitoneal Routes of Administration

Alveolar echinococcosis (AE) caused by the larval stage of Echinococcus multilocularis is serious parasitic diseases associated with the host´s immunosuppression. The effects of human non-immune dialyzable leukocyte extract (DLE) on immune cells in blood and spleen and parasitic cysts weight in Balb/c mice after oral (PO), subcutaneous (SC) and intraperitoneal administration (IP) were compared. The reduction in cysts weight (p < 0.01) was recorded after PO route, whereas moderate reduction was found after SC and IP routes. The elevation of lymphoid populations in blood and spleen was found after PO administration (p < 0.01) in parallel with reduced myeloid population. Infection-elicited decline in B220+B cells was partially abolished by PO route, but DLE routes did not influence the CD3+ T cells. The proportions of CD3+CD4+Th lymphocytes were moderately upregulated, whereas CD3+CD8+Tc populations were reduced after all DLE routes (p < 0.01). PO administration increased CD11b+MHCII^high blood monocytes, CD11b-SigleF+ cell, but not CD11b+Si-glecF+ eosinophils in the blood, stimulated after SC and IP routes. DLE induced downregulation of NO production by LPS-stimulated adherent splenocytes ex vivo. Con A-triggered T lymphocyte proliferation was associated with the elevated IFN-γ production and transcription factor Tbet mRNA expression. The alleviation of Th2 (IL-4) and Treg (TGF-β) cytokine production by lymphocytes ex vivo paralleled with downregulation of gene transcription for cytokines, GATA and FoxP3. Reduction of myeloid cells with suppressive activity was found. The SC and IP routes affected partially the cysts weights, diminished significantly gene transcription, NO levels and Th2 and Treg cytokines production. Results showed that PO route of DLE administration was the most effective in ameliorating immunosuppression via stimulation of Th1 type, reducing Th2 and Treg type of immunity and CD3+CD8+Tc lymphocytes in the blood and spleens during E. multilocularis infection in mice.

Novel albendazole-glucan particles for enhancing intestinal absorption and improving hepatic targeting

Background

Glucan particles (GPs) are derived from the Saccharomyces cerevisiae cell wall. The hollow particles composed of β-1,3-D-glucan have been extensively studied in terms of immune regulation and macrophage-targeted drug delivery. Albendazole (ABZ) is a benzimidazole drug with good anti-parasitic activity and is the drug recommended by the World Health Organization for the first-line treatment of hydatid disease.

Methods

A dynamic light scatterometer, scanning electron microscope, and transmission electron microscope were used to characterize the ABZ-GPs. High-performance liquid chromatography (HPLC), laser scanning confocal microscope (LSCM) and an in vivo small animal imaging system were used to evaluate theability of ABZ-GPs to be recognized by macrophages, whether ABZ-GPs are more readily absorbed and eliminated in the blood than the original ABZ drug in rats, and the ability of ABZ-GPs to target the mouse liver.

Results

The ABZ-GPs were successfully constructed to achieve fluorescence, magnetic resonance imagining, and laser confocal microscopy imaging. The glucan shell effectively protects ABZ from enzymatic degradation and from being pumped out in the gastrointestinal tract. The analysis of ABZ and its major metabolite albendazole sulfoxide in the rat plasma and mouse liver showed that compared to the ABZ suspension group, the degradation of ABZ-GPSs in the blood was low, and the targeting of ABZ-GPSs in the liver was significantly enhanced.

Conclusions

In the oral treatment of hepatic hydatid disease, GPs can be used as carriers to achieve the targeted transport of ABZ, which in turn can be used for the targeted therapy of liver echinococcosis. Thus, ABZ-GPs may be a promising form of targeted therapy.

Experimental treatment of cystic echinococcosis: Combination therapy with carvacrol and thymol versus albendazole

Cystic echinococcosis is a worldwide zoonotic disease caused by Echinococcus granulosus sensu lato (s.l.), which produces serious health and economic problems. For human treatment, chemotherapy with albendazole (ABZ), a derivative of benzimidazoles, is widely used. However, due to its low efficacy and the lack of alternatives to ABZ, novel compounds are urgently needed. Aromatic plants exhibit powerful pharmacological activities, are accessible, have a relatively low cost, and have generally mild toxicities, making them an effective choice to traditional therapies. In particular, the pharmaceutical properties of aromatic plants are partially attributed to essential oils (EOs). The aim of the present study was to assess the in vitro and in vivo effects of the combined carvacrol and thymol against E. granulosus sensu stricto (s.s.). The greatest protoscolicidal effect was observed with the 9:1 and 5:5 (carvacrol:thymol) combinations which caused a marked decrease in viability after 6 days post-incubation, agreeing with the ultrastructural changes obtained. Permeation of the cysts and loss of turgidity was observed with the incubation with the different combinations of carvacrol:thymol. In the clinical efficacy study, the combination of thymol (40 mg/kg) and carvacrol (40 mg/kg) caused a tendency to diminish the weight of the cysts in comparison with the control group. On the other hand, the treatment of infected mice with ABZ, thymol or carvacrol, caused a significant decrease in the weight of the cysts. In conclusion, we here demonstrated the efficacy of different concentrations of combined carvacrol and thymol against E. granulosus s.s. protoscoleces and murine cysts, where short periods of treatment were sufficient to achieve a pharmacological effect. Moreover, we observed a reduction in the weight of the cysts in experimentally infected mice after treatment with carvacrol and thymol. The strategy used has an advantage over synthetic drugs because natural compounds are generally safe and non-toxic. Moreover, the combination of two drugs with different modes of action would cause a reduction in the doses and treatment times. Based on the promising results obtained in vitro, in the future, different doses of the combined drugs will be assayed in vivo to determine the potential of these compounds for the treatment of cystic echinococcosis.

Very low frequency waves as selective probe for Cysticercus tenuicollis, Hydatid cyst and Coenurus cerebralis bio-analysis using single cell-signal recording

Comparative electric behavior of Cysticercus tenuicollis, Hydatid cyst and Coenurus cerebralis at the Very Low Frequency (VLF) region has been studied in detail. This investigation could be significant, because of the economic and public health importance of these parasitic infections in domestic animals. In this report, a single cell signal recording technique has been adopted for comparison using a stainless steel (type: 316, diameter: ~ 300 µm, height: 2.00 cm) two identical electrode system, implanted on the surface of the tested cysts with inter electrode distance of 0.50 cm at a ~ 6.0 giga ohm (GΩ) sealed condition (based on the situation of the implanted electrode system). This process was achieved based on applying electrical interaction between the cysts and the VLF electrical signal. Relative to the measured time domain signal (Current-time diagram), the frequency domain (Current-frequency diagram) was estimated via applying a "Discrete Fast Fourier Transform" (DFFT) algorithm at a fixed time interval (5.0 min). Factors, having important influence on the sensitivity of the detection system including the type (waveform) of different alternating-current (AC) triggering stimulus signals (such as direct current, square wave, triangular, sin (t), etc.), the amplitude, as well as the frequency were optimized automatically through a written "Visual Basic 6" program by one-factor-at-a-time method. Direct applying this AC triggering VLF voltage to the cysts resulted in tracing an AC electrical current vs. time that considered as the time domain wave. However, this electrical current was decayed rapidly versus time during maximum 30.0 s time scale. Applying the DFFT algorithm to the measured time domain, resulted in accessing to the frequency domain at the selected frequency range between 2 and 5 kHz that was considered as the selected frequency for the selective differentiation of C. tenuicollis, Hydatid cyst and C. cerebralis. The related probable mechanism of this process may be attributed to the correlation between the triggering potential and the cyst's electrical surface charge (Zeta potential) as the current source under similar conditions. The results of this study may help to introduce a new detection system for in vivo recognition of the cysts in future.

Calcifying nanoparticles initiate the calcification process of mesenchymal stem cells in vitro through the activation of the TGF-β1/Smad signaling pathway and promote the decay of echinococcosis

The role of the calcifying nanoparticles (CNPs) in the calcification process of the outer cyst wall in hepatic cystic echinococcosis (HCE) remains unknown. CNPs were isolated from the tissues of the patients with HCE. Western blotting, alkaline phosphatase staining, and alizarin staining were performed to detect the cellular calcium ion deposition induced by the CNPs. CCK-8 and flow cytometry assays were conducted to determine the effect of CNPs on the apoptosis of mesenchymal stem cells (MSCs). Western blot experiments were performed to examine the expression levels of apoptosis-related factors and TGF-β1/Smad signaling pathway constituents. Treatment with CNPs induced the differentiation of MSCs. Calcium-related proteins, including OPN, BMP-2, and RUNX2, were upregulated after the CNP treatment. Similarly, CNP exposure increased the cellular calcium ion deposition in MSCs. In addition, the expression of Bax and Caspase-8 was elevated by the CNPs in MSCs. Treatment with CNPs promoted MSC apoptosis and inhibited the MSC growth. The TGF-β1/Smad signaling pathway was also activated after the CNP treatment. This study indicated that CNPs may play a critical role in initiating calcification of the outer cyst wall of HCE and promote the decay of echinococcosis, providing a new strategy for the treatment of hepatic echinococcosis.

Antiparasitic Effects of Asteraceae Species Extracts on Echinococcus granulosus s.s

Cystic echinococcosis is a zoonotic disease caused by the parasite Echinococcus granulosus sensu lato (s.l.), which is worldwide distributed and causes long-lasting infections in animals and humans. The existing treatment is limited to the use of benzimidazoles, mainly albendazole (ABZ). However, it has unwanted side effects and its efficacy is about 50%. The Asteraceae family includes plants that have therapeutic applications (medicinal species) and has an important role in new drug development. The species belonging to a different genus of this family show a wide range of anti-inflammatory, antimicrobial, antioxidant, hepatoprotective, and antiparasitic activities, among others. The aim of the present study was to evaluate the in vitro efficacy of extracts of four Asteraceae species against protoscoleces of E. granulosus sensu stricto (s.s.). On the other hand, the Stevia aristata extract was assessed on the murine cyst of E. granulosus (s.s.) and the efficacy of S. aristata extract was investigated in a murine model of CE. Stevia satureiifolia, S. aristata, Grindelia pulchella, and G. chiloensis extracts at 100 μg/mL caused a decrease in protoscoleces viability; however, S. aristata extract produced the greatest in vitro protoscolicidal effect. After 20 days of treatment with the highest concentration (100 μg/mL) of S. aristata extract, protoscoleces viability decreased to 0%. The tegumental changes observed by scanning electron microscopy were consistent with the reduction in vitality. The collapse of the germinal layer was registered in 60 ± 5.8% and 83.3 ± 12.0% of cysts treated during 4 days with 50 and 100 μg/ml, respectively. The half maximal effective concentration (EC50) value of the S. aristata extract against E. granulosus (s.s.) cysts was 47.86 μg/mL (96 h). The dosage of infected animals with the 50 mg kg⁻¹ dose of S. aristata extract resulted in a significant reduction in cyst weight in comparison with the control group. In conclusion, S. aristata extract was demonstrated to exert a marked effect, both in vitro and in the murine model.

A systematic appraisal of the use of carvacrol-rich plants to treat hydatid cysts

Hydatid cysts occur in the larval stage of Echinococcus granulosus worms in vital organs such as the liver, lung, brain, kidney, heart and spleen. As a result, the formation of these cysts in humans and animals is considered one of the most catastrophic common infections in humans and animals. So far, there is no definitive effective treatment strategy for this disease in humans. Cyst eradication through surgery is the only treatment, which might be difficult or impossible in some cases. The most difficult aspect of cyst removal surgery is recurrence and anaphylactic shock. As a result, many scolicidal medications are ineffective at inactivating the content of hydatid cysts in vivo. Herbal medicines are now considered a potential treatment for the treatment of hydatid cysts due to their effective anti-cystic activities, minimal side effects, and ability to improve immunity. In the present review study, the anti-cystic role of carvacrol as one of the main constituents of the Lamiaceae family on hydatid cyst has been discussed. The results demonstrate that carvacrol-containing essential oils may be utilized as a hydatid cyst inhibitor. This study has also shown the synergistic activity of carvacrol, thymol and other active plant metabolites.

One-tube nested MGB Probe Real-time PCR assay for detection of Echinococcus multilocularis infection in plasma cell free DNA

INTRODUCTION

The main objective of this study was to develop a One-tube nested MGB probe real-time PCR Assay for detecting Echinococcus multilocularis infection in human plasma cell free DNA (cfDNA).

METHODS

cfDNA was extracted from 10 E.m.-infected patients using a NucleoSnap DNA Plasma Kit and characterized by genomic sequencing. We designed nested PCR primers and MGB probe for Echinococcus multilocularis detection. The specificity, sensitivity and reproducibility of this assay were analyzed, and its validity was confirmed in 13 early stage clinical samples.

RESULTS

Several Echinococcus multilocularis-specific sequences were detected in the cfDNA of E.m.-infected patients, and CBLO020001206.1 was selected as the candidate sequence. We designed the primers and probe for the one tube nested real-time PCR. No cross-reactions with E.g. were observed. The detection limit was as low as 1 copy for Echinococcus multilocularis. The coefficients of variation were lower than 5% in intra- and inter-assays. 11 out of 13 patients were positive with nested MGB Probe PCR Assay and 3 patients were positive without outer primer in early stage Alveolar Echinococcosis pateints.

CONCLUSION

The one-tube nested MGB probe real-time PCR assay is a simple, rapid, and cost-effective method for detection of Echinococcus multilocularis infection in patients' Plasma DNA.

Secretion into Milk of the Main Metabolites of the Anthelmintic Albendazole Is Mediated by the ABCG2/BCRP Transporter

Albendazole (ABZ) is an anthelmintic with a broad-spectrum activity, widely used in human and veterinary medicine. ABZ is metabolized in all mammalian species to albendazole sulfoxide (ABZSO), albendazole sulfone (ABZSO₂) and albendazole 2-aminosulphone (ABZSO₂-NH₂). ABZSO and ABZSO₂ are the main metabolites detected in plasma and all three are detected in milk. The ATP-binding cassette transporter G2 (ABCG2) is an efflux transporter that is involved in the active secretion of several compounds into milk. Previous studies have reported that ABZSO was in vitro transported by ABCG2. The aim of this work is to correlate the in vitro interaction between ABCG2 and the other ABZ metabolites with their secretion into milk by this transporter. Using in vitro transepithelial assays with cells transduced with murine Abcg2 and human ABCG2, we show that ABZSO₂ and ABZSO₂-NH₂ are in vitro substrates of both. In vivo assays carried out with wild-type and Abcg2^-/- lactating female mice demonstrated that secretion into milk of these ABZ metabolites was mediated by Abcg2. Milk concentrations and milk-to-plasma ratio were higher in wild-type compared to Abcg2^-/- mice for all the metabolites tested. We conclude that ABZ metabolites are undoubtedly in vitro substrates of ABCG2 and actively secreted into milk by ABCG2.

2-Deoxy-D-glucose and combined 2-Deoxy-D-glucose/albendazole exhibit therapeutic efficacy against Echinococcus granulosus protoscoleces and experimental alveolar echinococcosis

2-Deoxy-D-glucose (2-DG) is a glucose analog used as a promising anticancer agent. It exerts its effects by inhibiting the glycolytic energy metabolism to deplete cells of energy. The larval stage of Echinococcus relies on glycolysis for energy production. Therefore, in this study, we investigated the in vitro and in vivo efficacy of 2-DG against the larval stage of Echinococcus granulosus and E. multilocularis. 2-DG exhibited significant time- and dose-dependent effects against in vitro cultured E. granulosus protoscoleces and E. multilocularis metacestodes. A daily oral administration of 500 mg/kg 2-DG in E. multilocularis-infected mice effectively reduced the weight of metacestodes. Notably, the combination treatment, either 2-DG (500 mg/kg/day) + albendazole (ABZ) (200 mg/kg/day) or 2-DG (500 mg/kg/day) + half-dose of ABZ (100 mg/kg/day), exhibited a potent therapeutic effect against E. multilocularis, significantly promoting the reduction of metacestodes weight compared with the administration of 2-DG or ABZ alone. Furthermore, the combination significantly promoted apoptosis of the cells of metacestodes and inhibited glycolysis in metacestodes, compared with the administration of 2-DG or ABZ alone. In conclusion, 2-DG exerts an effective activity against the larval stage of Echinococcus. Thus, it may be a promising anti-Echinococcus drug, and its combination with ABZ may provide a new strategy for the treatment of echinococcosis in humans.

Echinococcosis is a serious but neglected helminthic zoonosis caused by the larval stage of Echinococcus granulosus and E. multilocularis. At present, clinical pharmacotherapy of echinococcosis, such as albendazole (ABZ) and mebendazole, has limited effectiveness. Thus, the development of novel therapeutic drugs for human echinococcosis is urgently needed. 2-Deoxy-D-glucose (2-DG) is a glucose analog used as a promising anticancer agent, and it exerts its effects by inhibiting the glycolytic energy metabolism to deplete cells of energy. Echinococcus in the host depends on glycolysis for energy production and glycolysis intermediates for other metabolic processes. Therefore, in this study, we investigated the efficacy of 2-DG against Echinococcus. 2-DG exerted an effective in vitro and in vivo activity against E. granulosus protoscoleces and E. multilocularis metacestodes, and the combination of this drug with ABZ further improved the therapeutic effect. Therefore, 2-DG can be developed as a promising anti-Echinococcus drug, and its combination with ABZ may provide a new strategy for the treatment of human echinococcosis in the future.

Anthelmintic activity of Stevia multiaristata extract against Echinococcus granulosus sensu stricto

Cystic echinococcosis is a zoonotic disease caused by the larval stage of the parasite Echinococcus granulosus sensu lato. The available anti-parasitic treatment is mostly limited to a continuous administration of albendazole. However, due to its numerous side-effects and efficacy of around 50%, there is a need to find new drugs to improve the treatment for this disease. In the current study, the in vitro and in vivo efficacy of a Stevia multiaristata extract against E. granulosus sensu stricto (s.s.) was demonstrated. Stevia multiaristata extract (100 and 50 μg mL−1) caused a quick viability decrease on protoscoleces which was consistent with the observed tegumental alterations. Loss of turgidity was detected in 95 ± 3.4% of cysts incubated with S. multiaristata extract during 2 days (100 μg mL−1) and the collapse of the germinal layer was observed in 60 ± 9.3% of cysts treated with 100 μg mL−1 of the S. multiaristata extract during 4 days. The half maximal effective concentration value was 69.6 μg mL−1 and the selectivity index for E. granulosus s.s. cysts was 1.9. In this clinical efficacy study, the treatment of infected mice with the S. multiaristata extract (50 mg kg−1) caused a significant decrease in the weight of the cysts compared with the control group. These results coincided with the tissue damage observed in the cysts at the ultrastructural level. In conclusion, we observed high protoscolicidal and cysticidal effects, and significant reduction in the weight of the cysts in experimentally infected mice following treatment with the S. multiaristata extract.

Autocrine osteopontin is involved in maintaining the growth and metastasis of Echinococcus multilocularis

Alveolar echinococcosis is a zoonotic disease that seriously endangers human health. This study aims to investigate the effects of osteopontin on the growth and intra- or extra-hepatic metastasis of Echinococcus multilocularis. Mice were randomly divided into untreated (control group, n = 25), PBS (n = 25), Lv3-NC (n = 25), and Lv-OPN-734 (n = 25) groups. Knockdown OPN by injecting lentivirus through the intraperitoneal portal vein, the metastatic lesions infected with Echinococcus multilocularis and adjacent liver tissues were observed, and the expression of osteopontin and epidermal growth factor receptor pathway-related molecules were studied. Gross observation of specimens suggested that there was no extra- hepatic metastasis, and mild intrahepatic invasion was observed in the Lv-OPN-734 group after 4 months of infection, and lung metastasis occurred in the Lv3-NC group. Western-blot and immunohistochemical staining results showed that the protein expression of OPN, phosphorylation of epidermal growth factor receptor and downstream molecules of the pathway decreased significantly after osteopontin knockdown, whereas the levels of non-phosphorylated proteins did not change significantly. In human tissues, through western-blot and immunohistochemical staining we found that compared with the control group, the expression of OPN in the liver tissues infected with Echinococcus multilocularis were higher than that in the control group. These findings indicate that osteopontin is involved in maintaining the growth and metastasis of Echinococcus multilocularis, suggesting that osteopontin may be a potential target for the treatment of alveolar echinococcosis.

The Recombinant Eg.P29-Mediated miR-126a-5p Promotes the Differentiation of Mouse Naive CD4+ T Cells via DLK1-Mediated Notch1 Signal Pathway

Cystic echinococcosis (CE) is a zoonotic parasitic disease spread worldwide caused by Echinococcus granulosus (Eg), which sometimes causes serious damage; however, in many cases, people are not aware that they are infected. A number of recombinant vaccines based on Eg are used to evaluate their effectiveness against the infection. Our previous report showed that recombinant Eg.P29 (rEg.P29) has a marvelous immunoprotection and can induce Th1 immune response. Furthermore, data of miRNA microarray in mice spleen CD4⁺ T cells showed that miR-126a-5p was significantly elevated 1 week after immunization by using rEg.P29. Therefore, in this perspective, we discussed the role of miR-126a-5p in the differentiation of naive CD4⁺ T cells into Th1/Th2 under rEg.P29 immunization and determined the mechanisms associated with delta-like 1 homolog (DLK1) and Notch1 signaling pathway. One week after P29 immunization of mice, we found that miR-126a-5p was significantly increased and DLK1 expression was decreased, while Notch1 pathway activation was enhanced and Th1 response was significantly stronger. The identical conclusion was obtained by overexpression of mmu-miR-126a-5p in primary naive CD4⁺ T cells in mice. Intriguingly, mmu-miR-126a-5p was significantly raised in serum from mice infected with protoscolex in the early stages of infection and markedly declined in the late stages of infection, while has-miR-126-5p expression was dramatically reduced in serum from CE patients. Taken together, we show that miR-126a-5p functions as a positive regulator of Notch1-mediated differentiation of CD4⁺ T cells into Th1 through downregulating DLK1 in vivo and in vitro. Hsa-miR-126-5p is potentially a very promising diagnostic biomarker for CE.

Salvage Therapy for Alveolar Echinococcosis—A Case Series

Benzimidazoles are the only approved drugs for the treatment of inoperable human alveolar echinococcosis but may be limited due to intolerance or, rarely, ineffectiveness. A medical second-line or salvage therapy is not available, though it is urgently needed. We report long-term follow-up data from 14 patients who underwent salvage therapy with repurposed drugs with cumulatively 53.25 patient-years. Treatment response was evaluated by both clinical outcome and image studies, preferably PET/CT. Eleven patients received amphotericin B, and 70% of evaluable cases showed some positive treatment response, but side effects often limited therapy. Five patients received nitazoxanide, of which two showed clear progression but one achieved a lasting stable disease. One patient was treated with mefloquine combination therapy in advanced disease, and overall, a positive treatment response could not be assessed. Furthermore, we report on one patient receiving pembrolizumab for a concomitant malignancy, which did not result in a reduction of echinococcal manifestation. In summary, current options of salvage therapy can sometimes induce persistent disease control, although with potentially significant side effects and high treatment costs, and mortality remains high. No clear recommendation for a salvage therapy can be given; treatment remains highly experimental, and non-pharmaceutical interventions have to be considered.

Evaluation of Eosinophilic Cationic Protein as a Marker of Alveolar and Cystic Echinococcosis

Echinococcosis is a neglected zoonotic disease and a worldwide public health problem caused by infection with the larval stages of taeniid cestodes of the genus Echinococcus. In vitro studies have demonstrated a protoscolecidal effect of eosinophilic cationic protein (ECP), a granule protein of eosinophilic granulocytes, against E. granulosus. Therefore, the main objective of this study was to evaluate ECP as a biomarker in the treatment of alveolar echinococcosis (AE) and cystic echinococcosis (CE). Data were collected retrospectively from the Vienna Echinococcosis Cohort over 7 years until December 2020. Altogether, 32 patients (16 AE and 16 CE) were included. In the selected patients, serum ECP values were compared before and after the beginning of an operative and/or benzimidazole (BMZ) therapy. Mean ECP serum levels before intervention were significantly (p < 0.05) elevated at 34.0 ± 22.9 μg/L in AE patients and at 38.6 ± 19.9 μg/L in CE patients compared to the control group. After the intervention, mean ECP levels decreased significantly (p < 0.05) to 20.4 ± 14.6 μg/L in AE patients and to 22.4 ± 8.3 μg/L in CE patients. Furthermore, ECP showed a significant (p < 0.05) correlation of k = 0.56 with PET–CTI. Based on the significant decrease after operative and/or BMZ treatment and the correlation with clinical markers such as PET–CTI, it is recommended to investigate ECP more intensively as a marker of AE and CE in prospective studies with larger cohorts.

Status and prospect of novel treatment options toward alveolar and cystic echinococcosis

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are the two most important global parasitic infectious diseases caused by species of Echinococcus granulosus and E. multilocularis, respectively. Although numerous trials have been performed in search of novel therapeutic options to curb the neglected zoonosis, no other nonsurgical options are currently available to replace the licensed anti echinococcal drugs albendazole (ABZ) and mebendazole (MBZ). A safer and more effective treatment plan for echinococcosis is therefore urgently needed to compensate for this therapeutic shortfall. Here, we present a review of the literature for state-of-the-art valuable anti-parasitic compounds and novel strategies that have proved effective against CE and AE, which includes details about the pharmaceutical type, practical approach, experimental plan, model application and protoscolecidal effects in vivo and in vitro. The content includes the current application of traditional clinical chemicals, the preparation of new compounds with various drug loadings, repurposing findings, combined programs, the prospects for Chinese herbal medicines, non-drug administrations and the exploration of target inhibitors based on open-source information for parasitic genes. Next the conventional experimental projects and pharmacodynamic evaluation methods are systematically summarized and evaluated. The demands to optimize the construction of the echinococcosis model and improve the dynamic monitoring method in vivo are also discussed given the shortcomings of in vivo models and monitoring methods.

The expression of cytokeratin and apoptosis-related molecules in echinococcosis related liver injury

The study aimed to investigate the expression of cytokeratin and apoptosis-related molecules in the livers of two types of hepatic echinococcosis mice models and to preliminarily explore the relationship between the expression of cytokeratin and apoptosis in echinococcosis related liver injury. We established a mouse model infected by Echinococcus granulosus and Echinococcus multilocularis and observed the expression of cytokeratin and apoptosis related proteins in the two types of hepatic echinococcosis tissues during different stages by immunohistochemical staining. A co-culture model was established using normal hepatocytes and different concentrations of E. granulosus and E. multilocularis protoscoleces. Cell Counting Kit-8 was used to detect cell proliferation, flow cytometry was used to detect hepatocyte apoptosis, and western blot was used to quantify cytokeratin and apoptosis-related proteins, such as caspase3, caspase9, Bcl-2, and Bax. Surgical specimens were obtained from patients with hepatic echinococcosis to analyze the expressions of cytokeratin, caspase3, caspase9, Bcl-2, and Bax by western blot. The expressions of cytokeratin and caspase3 were analyzed by immunohistochemistry. The qRT-PCR method was used to determine the expression of CK8 and CK18 in the liver tissues. In vivo experiments showed that compared to that in the control group, the cytokeratin and caspase3 proteins in the liver tissues of the two types of hepatic echinococcosis were strongly expressed around the lesions of liver echinococcosis; there was a difference between cytokeratin expression of the two different echinococcosis parasites in the liver. Echinococcus granulosus and Echinococcus multilocularis in the co-culture model in vitro could promote the expression of CK, caspase3, caspase9, and Bax protein, decrease the expression of Bcl-2, promote hepatocyte apoptosis, and inhibit cell proliferation; in clinical samples, we found that compared with that in the normal tissues, the expression of cytokeratin, caspase3, caspase9, and Bax in echinococcus tissues was high, but that in Bcl-2 was low. Furthermore, the expression of CK8 and CK18 mRNA were higher in echinococcus tissues than that in the normal tissues and immunohistochemistry analysis also showed that cytokeratin and caspase3 levels were higher in echinococcus tissues than that in the normal tissues. The expression of cytokeratin and apoptosis-related molecules, reflecting liver damage, is high in the liver and is caused due to hepatic echinococcosis. This study provides the first evidence of cytokeratin could be useful for evaluating liver tissue damage caused by echinococcus infection.

Role of Cytokines on the Progression of Liver Fibrosis in Mice Infected with Echinococcus multilocularis

Background

Liver fibrosis is a significant pathological change of Echinococcus multilocularis (E. multilocularis) infection. This study aimed to explore the role of cytokines on the progression of liver fibrosis in mice infected with E. multilocularis.

Methods

Liver histopathological features at 2, 8, 30, 90 and 180 d were quantified by inflammatory severity score. The expression levels of inflammatory cytokines, fibrosis-related cytokines and hepatic cell apoptosis were measured using qRT-PCR and immunohistochemistry.

Results

At the early stage of infection, parasite stimulation triggers the rapid recruitment of immune cells, such as macrophages and neutrophils. These infiltrated immune cells then produce a large number of cytokines, such as iNOS (inducible nitric oxide synthase), a pro-inflammatory cytokine; TGF-β (transforming growth factor) activated HSCs (hepatic stellate cells) to promote the proliferation of fibroblasts and secretion of ECM (extracellular matrix); MMP9 (matrix metalloproteinase 9) degraded basal ECM and facilitated its replacement by a highly dense interstitial matrix. At the middle and late stages of infection, the expression of IL-10 (interleukin-10) with general inhibitory effect was increased. The imbalance of fiber formation and degradation aggravated liver fibrosis. Meanwhile, the whole process of E. multilocularis infection was accompanied by the necrosis and apoptosis of hepatic cells.

Conclusion

Along with the expansion of parasitic infection, dynamic changes in cytokine expression were observed on the liver fibrosis progression, which is helpful to provide some new ideas for the prevention and treatment of liver fibrosis in mice infected with E. multilocularis.

Assessment of the Therapeutic Efficacy of Silver Nanoparticles against Secondary Cystic Echinococcosis in BALB/c Mice

Background: Cystic echinococcosis (CE) is a highly prevalent parasitic disease resulting from the hydatid cyst of Echinococcus granulosus. It is also described as a zoonotic disease and considered a neglected tropical infection. Aim: This study assessed the antiparasitic activity of silver nanoparticles (AgNPs), against E. granulosus infection in BALB/c mice. Methods: The green synthesis of AgNPs was accomplished using Zizyphus spina-christi leaves. AgNPs were orally administered to BALB/c mice for acute short-term toxicity evaluation, in doses of 50 mg, 100 mg, 200 mg, and 300 mg/kg, and observations for toxic signs were carried out at 24, 48 h, and 14 days, continuously. Moreover, a total of 20 mice divided into two groups were intraperitoneally administered with 1500 viable protoscoleces for secondary hydatidosis infection. Results: The results showed that AgNPs did not induce any adverse effects or signs and no death, in either group of mice. The histopathological findings in the liver, kidneys, and intestine of the mice administered with AgNPs revealed mild histological effects compared with the control ones. The treated-infected mice showed a change in the appearance of the liver hydatid cysts from hyaline to milky cloudy compared with the untreated infected mice. Conclusion: Biosynthesized AgNPs showed anti-hydatic effects and are suggested as anti-echinococcal cyst treatment.

The combination of carvacrol and albendazole enhanced the efficacy of monotherapy in experimental alveolar echinococcosis

Alveolar echinococcosis is a helminthic zoonosis caused by the larval stage of Echinococcus multilocularis. When surgical resection of the parasite is not feasible, pharmacological treatment with albendazole is the only option. Due to the difficulties in achieving the success of treatment, it is necessary to find new drugs to improve the treatment of this disease. In the present work, the efficacy of carvacrol alone or combined with albendazole was evaluated against E. multilocularis metacestodes. The association of carvacrol with albendazole produced a greater in vitro effect than the compounds incubated separately. The most effective treatment was the combination of 10 μg/ml of carvacrol and 1 μg/ml of albendazole. In the clinical efficacy study, treatment of infected mice with carvacrol (40 mg/kg) and albendazole (25 mg/kg) reduced the weight of metacestodes by 29 % and 50 %, respectively; while the combination of drugs had an efficacy of 83 %. These results coincided with the tissue damage observed at the ultrastructural level. In conclusion, carvacrol and albendazole combination enhanced the efficacy of monotherapy. This strategy would allow to improve the efficacy of the treatment without increasing the doses of albendazole or lengthen the treatment period, reducing the occurrence of adverse effects.

Triphase contrast-enhanced CT to evaluate indications for autologous liver transplantation in patients with end-stage hepatic alveolar echinococcosis

Autologous liver transplantation (ALT) to cure end-stage hepatic alveolar echinococcosis (HAE) requires that hepatobiliary surgeons understand the invasion of intrahepatic structure and adjacent tissues or organs. Triphase contrast-enhanced CT of the liver has been widely used for diagnosis and preoperative evaluation of HAE. Three-dimensional (3D) reconstruction allows for accurate measurement of remnant liver volume (RLV). The objective of the study was to evaluate value of triphase contrast-enhanced CT together with 3D reconstruction in preoperative evaluation of indications for ALT in patients with end-stage HAE. This cohort include twenty-one consecutive patients with end-stage HAE, who preoperatively underwent triphase enhanced CT together with 3D reconstruction for ALT. To depict the indications, the 2D image data were reviewed statistically focusing on porta hepatis invasion, retrohepatic vena cava (RHVC) involvement and degrees of intrahepatic vessel invasion, and the 3D reconstruction was performed to obtain ratio of RLV to standard liver volume (SLV). The results showed that 95.24% patients (20/21) had porta hepatis invasion. When lesions located in right liver lobe, porta hepatis invasion occurred most commonly in the second and third porta hepatis (7/10), whereas the first, second and third porta hepatis were most commonly invaded by lesions in the right and caudate / left medial liver lobes (7/11) (P < 0.05). The mean value of longitudinal invasion of RHVC was 8.0 cm, and 95.2% (20/21) of patients had RHVC invasion with ≥ 180° circumferential invasion. As for the important vascular events, moderate and severe invasion occurred most commonly in the right hepatic vein, right branch of portal vein and RHVC each in 95.2% (20/21) patients (P < 0.05). We also found that preoperative CT had a good agreement with intraoperative findings in assessing intrahepatic vascular involvement by HAE (kappa index = 0.77). The estimated average ratio of RLV to SLV was 0.95 (range, 0.43–1.62). In conclusion, the 2D contrast-enhanced CT could well depict anatomic location and size of HAE, and invasion of porta hepatis and vascular by this disease, and involvement of other adjacent organs and tissues. Above all, 3D reconstruction could accurately measure RLV in patients with end-stage HAE for ALT.

In vitro and in vivo efficacy of thiacloprid against Echinococcus multilocularis

BACKGROUND

Alveolar echinococcosis (AE) is a chronic zoonosis caused by the larval form of Echinococcus multilocularis (E. multilocularis). Current chemotherapy against AE has relied on albendazole and mebendazole, which only exhibit parasitostatic and not parasiticidal efficacy. Therefore, novel compounds for the treatment of this disease are needed.

METHODS

Phosphoglucose isomerase (PGI) assays were used for compound screening of seven neonicotinoids. The anti-parasitic effects of thiacloprid were then evaluated on E. multilocularis metacestode vesicles, germinal cells and protoscoleces in vitro. Human foreskin fibroblasts (HFF) and Reuber rat hepatoma (RH) cells were used to assess cytotoxicity. Glucose consumption in E. multilocularis protoscoleces and germinal cells was assessed by measuring uptake of 2-deoxyglucose (2-DG). Molecular docking was used to evaluate the potential binding sites of thiacloprid to acetylcholine receptors. In vivo efficacy of thiacloprid was evaluated in mice by secondary infection with E. multilocularis. In addition, ELISA and flow cytometry were used to evaluate the effects of cytokines and T lymphocyte subsets after thiacloprid treatment. Furthermore, collagen deposition and degradation in the host lesion microenvironment were evaluated.

RESULTS

We found that thiacloprid is the most promising compound, with an IC50 of 4.54 ± 1.10 μM and 2.89 ± 0.34 μM, respectively, against in vitro-cultured E. multilocularis metacestodes and germinal cells. Thiacloprid was less toxic for HFF and RH mammalian cell lines than for metacestodes. In addition, thiacloprid inhibited the acetylcholinesterase activity in protoscoleces, metacestodes and germinal cells. Thiacloprid inhibited glucose consumption by protoscoleces and germinal cells. Subsequently, transmission electron microscopy revealed that treatment with thiacloprid damaged the germinal layer. In vivo, metacestode weight was significantly reduced following oral administration of thiacloprid at 15 and 30 mg/kg. The level of CD4+ T lymphocytes in metacestodes and spleen increased after thiacloprid treatment. Anti-echinococcosis-related cytokines (IL-2, IL-4, IL-10) were significantly increased. Furthermore, thiacloprid inhibited the expression of matrix metalloproteinases (MMPs 1, 3, 9, 13) and promoted collagen deposition in the host lesion microenvironment.

CONCLUSIONS

The results demonstrated that thiacloprid had parasiticidal activity against E. multilocularis in vitro and in vivo, and could be used as a novel lead compound for the treatment of AE.

Hepatic Alveolar Echinococcosis

Hepatic alveolar echinococcosis (HAE) is a rare but severe zoonosis caused by the pseudotumoral intrahepatic development of the larval stage of the tapeworm Echinococcus multilocularis. HAE is present only in the Northern Hemisphere, predominantly in China. Currently, there is a significant resurgence of cases in historically endemic areas associated with emergence of HAE in countries not previously concerned. Today, in European countries, HAE is often discovered by chance; however, clinicians should be made aware of opportunistic infections that progressively emerged recently as a result of therapeutic or pathological immunosuppression. Ultrasonography is the key first-line diagnostic procedure, with specific serology providing confirmation in 95% of the cases. Albendazole, only parasitostatic, is the mainstay for treatment. Surgical resection, if feasible, is the gold standard for treatment, and more patients are currently eligible for this option because of an earlier diagnosis. The prognosis has considerably improved but remains poor in countries where access to care is less favorable.

In vivo and in vitro efficacy of crocin against Echinococcus multilocularis

Background

Alveolar echinococcosis (AE) is a fatal zoonosis caused by the larvae of Echinococcus multilocularis. However, current chemotherapy treatment options are based on benzimidazoles [albendazole (ABZ) and mebendazole], which have limited efficacy. Therefore, novel drugs are necessary for the treatment of this disease.

Methods

The anthelmintic effects of crocin were tested on E. multilocularis metacestodes, germinal cells and protoscoleces in vitro. Human foreskin fibroblasts (HFFs) and Reuber rat hepatoma (RH) cells were used to assess cytotoxicity. The in vivo efficacy of crocin was investigated in mice following secondary infection with E. multilocularis. Furthermore, collagen deposition and degradation in host tissues around the metacestodes were evaluated.

Results

In vitro, crocin had a median effective concentration of 11.36 μM against cultured E. multilocularis metacestodes, while it reduced germinal cell viability at a median inhibitory concentration of 10.05 μM. Crocin was less toxic to HFFs and RH mammalian cell lines than to metacestodes. Transmission electron microscopy revealed that crocin treatment resulted in structural damage in the germinal layer. In addition, 60.33 ± 3.06% of protoscoleces were killed by treatment with 10 μM crocin for 7 days, indicating that crocin has a parasiticidal effect. In vivo, the metacestode weight was significantly reduced after the administration of crocin at 50 mg/kg and 100 mg/kg (55.1 and 68.1%, respectively). Metacestode pathology showed structural disruption of the germinal and laminated layers after crocin treatment. The crocin- and ABZ-treated groups presented significant increases in the levels of interleukin (IL)-2 and IL-4. Furthermore, crocin inhibited the expression of matrix metalloproteinases (MMPs) (MMP2 and MMP9) and promoted collagen deposition in the metacestode.

Conclusions

Crocin was demonstrated to exert parasiticidal activity against E. multilocularis in vitro and in vivo, and can be developed as a novel drug for the treatment of AE.

Graphical abstract

Supplementary information

The online version contains supplementary material available at 10.1186/s13071-021-04866-4.

Epidemiological and Clinical Characteristics of Alveolar Echinococcosis: An Emerging Infectious Disease in Alberta, Canada

Human alveolar echinococcosis (AE) is a zoonotic cestode infection which is usually fatal in the absence of treatment. Treatment involves major surgery or indefinite antiparasitic therapy. The incidence is rising in Europe and Asia, with an increased risk observed in immunocompromised individuals. Previously, AE acquisition in North America was extremely rare, except for one remote Alaskan Island. Recent studies have demonstrated a new European-like strain of Echinococcus multilocularis (Em) in wildlife and in human AE in western Canada. We report the experience of all AE patients diagnosed in Alberta. Each was diagnosed by histopathology, serology, and PCR-confirmed by a reference laboratory. Seventeen cases of human AE, aged 19-78 years, nine females, were diagnosed between 2013 and 2020: all definitely or probably acquired in Alberta. Six lived in urban areas, and 14 had kept dogs. In eight, the lesions were found incidentally on abdominal imaging performed for other indications. Six were immunocompromised to varying degrees. Six were first diagnosed at surgery. All have been recommended benzimidazole therapy. One died of surgical complications. Clinicians should be aware of this diagnostic possibility in patients presenting with focal nonmalignant hepatic mass lesions. Greater urbanization of coyotes, the predominant definitive host of Em in Alberta, and growing numbers of immune suppressed individuals in the human population may lead to increasing recognition of AE in North America.

In vivo efficacy of combination therapy with albendazole and atovaquone against primary hydatid cysts in mice

Alveolar echinococcosis (AE) is caused by the larval stage of Echinococcus multilocularis. Chemotherapy for AE involves albendazole (ABZ), which has shown insufficient efficacy. More effective chemotherapy for AE is needed. Previously, we have demonstrated that atovaquone (ATV), an antimalarial, inhibits mitochondrial complex III of E. multilocularis and restricts the development of larval cysts in in vivo experiments. Therefore, in this study, we evaluated the efficacy of ABZ and ATV combination therapy on E. multilocularis in culture and in vivo experiments. Protoscoleces were treated with 50 μM ABZ and/or ATV in the medium; the duration of parasite elimination was determined under aerobic and anaerobic culture. In the in vivo experiment, the effects of ABZ and ATV combination treatment in BALB/c mice infected orally with eggs from the feces of an adult-stage E. multilocularis-infected dog were compared with those of standard oral ABZ therapy. In the culture assay, the duration of elimination associated with ABZ and ATV combination treatment was shorter than that associated with ATV alone under aerobic conditions. Protoscolex viability progressively reduced owing to the combination treatment under anaerobic conditions; however, either drug used singly did not exhibit antiparasitic effects under hypoxia. Furthermore, compared with ABZ alone, the combination treatment significantly reduced the growth of the primary cyst in the liver of mice infected orally with parasite eggs (P = .011). ATV enhances the effect of ABZ in the treatment of AE in mice.

Emerging human alveolar echinococcosis in Hungary (2003-2018): a retrospective case series analysis from a multi-centre study

Background

Human alveolar echinococcosis (AE) caused by Echinococcus multilocularis is an underreported, often misdiagnosed and mistreated parasitic disease mainly due to its low incidence. The aim of this study was to describe the epidemiological and clinical characteristics of human AE patients in Hungary for the first time.

Method

Between 2003 and 2018, epidemiological and clinical data of suspected AE patients were collected retrospectively from health database management systems.

Results

This case series included a total of 16 AE patients. The mean age of patients was 53 years (range: 24–78 years). The sex ratio was 1:1. Four patients (25%) revealed no recurrence after radical surgery and adjuvant albendazole (ABZ) therapy. For five patients (31.3%) with unresectable lesions, a stabilization of lesions with ABZ treatment was achieved. In seven patients (43.8%), progression of AE was documented. The mean diagnostic delay was 33 months (range: 1–122 months). Three AE related deaths (fatality rate 18.8%) were recorded.

Conclusions

AE is an emerging infectious disease in Hungary with a high fatality rate since based on our results, almost every fifth AE patient died in the study period. Differential diagnosis and appropriate surgical and medical therapy for AE is an urging challenge for clinicians in Hungary, as well as in some other European countries where E. multilocularis is prevalent.