Bile salt-mediated activation of a type-1 nuclear receptor of Fasciola gigantica (FgNR1).

Fascioliasis is a zoonotic disease in regard to public health, which is sporadically reported from different parts of the world. Adult worms infect the liver and bile ducts, but extrahepatic involvement and the development of parasitic myositis and muscle mass caused by Fasciola hepatica are uncommon and very rare. A 55-year-old Iranian female presented with a history of abdominal pain, epigastric tenderness without pallor and jaundice, along with significant weight loss for the past five months. Microscopic examination of the stool did not identify adult worms or parasite eggs. Laboratory findings were almost normal, while erythrocyte sedimentation rate (ESR) was 32mm/hour, triglyceride 330mg/dL and eosinophil 6%. Hepatitis B surface antigen (HBsAg) and anti-Hepatitis C virus (HCV) were non-reactive, whereas Hepatitis B surface antibody (HBsAb) was 260.7IU/L. Ultrasound of the tissue revealed a mass in the abdominal wall in the right upper quadrant. After her admission to the hospital, a flatworm emerged from the rectus abdominis muscle of the patient. Histopathological examination of the excised lesion showed parasite-induced myositis with abscess formation and a granulomatous foreign body reaction. Based on the morphological characteristics of the worm and serological assessment, the worm was identified as Fasciola hepatica. The patient was treated with triclabendazole and underwent clinical and paraclinical follow-up for 90days. This case highlights the importance of diagnosing Fasciola hepatica in the differential diagnosis of unexplained subcutaneous or intramuscular nodules, especially in patients with a history of travel to endemic areas. The current case is one of the rarest cases of extrahepatic involvement (muscular fascioliasis) reported in Iran, a country where Fasciola infection is endemic in its northern regions.

Gastrointestinal parasitic infections constitute a major constraint to equine health and productivity, particularly in tropical regions where climatic and environmental conditions favor parasite survival and transmission. In Côte d'Ivoire, epidemiological data regarding gastrointestinal parasites in horses remain limited, especially in urban and peri-urban settings such as the district of Abidjan. This study aimed to determine the prevalence, diversity, and associated risk factors of gastrointestinal parasites affecting horses in the study area. A descriptive and analytical cross-sectional study was conducted from September 2024 to February 2025 among 277 horses originating from 19 equine facilities, including 8 riding schools and 11 breeding farms, located in the district of Abidjan. Fresh fecal samples were collected and analyzed using four coprological techniques: direct examination, flotation, the simplified Ritchie concentration method, and Ziehl-Neelsen staining. Statistical analyses, including chi-square tests and logistic regression, were performed to identify factors significantly associated with parasitic infections at a significance threshold of p ≤ 0.05. The overall prevalence of gastrointestinal parasites was 88.80%, indicating widespread circulation of equine gastrointestinal parasites within the study area. Fifteen parasite species were identified, with predominance of Strongylus spp. (48.37%), Parascaris equorum (40.07%), cyathostomins (Cyathostominae) (30.68%), Fasciola hepatica (29.24%), and Cryptosporidium parvum (28.51%). Nematodes represented the predominant parasitic group. Significant associations were observed between parasitic infections and management-related factors, particularly feeding practices and type of equine activity. Horses from riding schools appeared more exposed to certain parasitic infections compared with horses raised on breeding farms. The high prevalence and diversity of gastrointestinal parasites observed among horses in the district of Abidjan highlight an important equine health concern in Côte d'Ivoire. These findings emphasize the need to strengthen integrated parasite control strategies, including regular parasitological monitoring, improved hygiene and management practices, rational use of anthelmintics to reduce the risk of resistance, and targeted deworming programs. Reinforcing veterinary surveillance and increasing awareness among horse owners and managers could substantially contribute to improving equine health and productivity in the study area.

Multiple sclerosis (MS) is characterized by chronic neuroinflammation and progressive demyelination, with current therapies failing to adequately address both processes simultaneously. Helminth-derived excretory–secretory products (ESP) are immunomodulatory molecules that suppress host inflammation and are promising candidates for MS treatment. However, their capacity to promote remyelination remains poorly understood. This study investigated the effects of Fasciola hepatica ESP in the cuprizone-induced demyelination model. Male C57BL/6 mice were divided into four groups: control (CON), control + FES (CON + FES), cuprizone (CUP), and cuprizone + FES (CUP + FES). FES was administered intraperitoneally during the demyelination phase. Motor and cognitive functions were evaluated using open field, rotarod, wire grip, and shuttle box tests. Neuroinflammation was assessed by measuring TNF and IL-1β levels, while myelin-related changes were evaluated by MBP and Olig2 expression (ELISA and qPCR) and Luxol Fast Blue staining. FES treatment significantly reduced pro-inflammatory cytokines, increased MBP and Olig2 levels, improved myelin integrity, and enhanced motor and cognitive performance compared to untreated cuprizone mice, though full recovery to control levels was not achieved. These findings demonstrate that FES attenuates neuroinflammation and is associated with partial improvements in myelin-related outcomes in the cuprizone model, supporting the therapeutic potential of helminth-derived molecules for MS.

Analysis of pathological histochemical characteristics of yak pancreas induced by Fasciola hepatica.

Dynamic immune modulation in fasciolosis: From protective to permissive responses.

Age-dependent spatial patterns of gastrointestinal parasites in goats across an extensive mountainous system in Argentina.

Fascioliasis is a foodborne trematode infection caused by Fasciola hepatica and Fasciola gigantica. It is caused by ingestion of undercooked aquatic vegetation containing infective stage metacercariae. Symptoms in the acute stage include fever, abdominal pain and eosinophilia and in the chronic stage symptoms of biliary obstruction or cholangitis. Very few fascioliasis cases have been reported from India. In the last 1 year, we diagnosed six cases of fascioliasis who presented with acute stage symptoms. They were diagnosed by characteristic dietary history, liver abscess on imaging and eggs of Fasciola in stool. They were successfully treated with Triclabendazole or Nitazoxanide.

High-resolution climate modelling of fasciolosis risk in Australia: A One Health early-warning framework

The liver flukes Fasciola hepatica and Fasciola gigantica cause fasciolosis, a zoonotic disease of major health and livestock importance. To evade host immunity, these parasites secrete immunomodulatory molecules, including fatty acid-binding proteins (FABPs), which are essential for parasite survival by mediating fatty acid uptake and transport, and by exerting anti-inflammatory effects that promote immune evasion and chronic infection. This study investigates the roles of F.hepatica FABPs' in nutrient acquisition, immune modulation, and parasite survival, assessing their potential as vaccine, diagnostic, and therapeutic targets. We cloned all seven FhFABP isoforms and expressed six recombinantly in yeast. Gene expression analysis showed stage-specific patterns, with the highest levels in adult flukes. Isoform-specific analysis further highlighted stage-dependent expression dynamics, and functional characterization revealed distinct fatty acid-binding properties, suggesting adaptive roles in parasite survival. We assessed IgG responses in infected sheep, finding peak titer against FhFABP5 at 6-8weeks post-infection (WPI) and a strong, prolonged response to FhFABP4, lasting 6-12weeks. These results highlight FhFABPs as immunogenic targets for diagnostics or vaccines. Additionally, FhFABPs differentially modulated the activity of human monocyte-derived dendritic cells. Our findings emphasize the multifaceted roles of FhFABPs in nutrient acquisition and immune modulation, underscoring their potential as targets for vaccines, diagnostics, and anti-inflammatory therapies.

Lung cancer is one of the most fatal malignancies. The connection between parasitic infections and cancer development has become an interesting subject. This study evaluates the impact of Fasciola hepatica (F. hepatica) excretory-secretory (ES) antigens on various cellular processes, including cell viability, apoptosis, cell cycle progression, reactive oxygen species (ROS) production, and the expression of markers such as SOX-9, β-catenin, CD44, and CD133 in A549 lung cancer cells. F. hepatica was collected from sheep livers, washed, and cultured in RPMI medium for ES antigens preparation. A549 lung cancer cells were cultured and treated with varying concentrations of ES antigens. The cytotoxic effects of ES antigens on A549 cells were assessed with the MTT test. Apoptosis, necrosis, cell cycle, and ROS levels were quantified using flow cytometry. Real-time PCR was used to analyse the expression levels of SOX-9, β-catenin, CD44, and CD133 genes. The protein concentration of the antigens was between 60 and 270µg/ml after 24 and 48h. The MTT cytotoxicity assay revealed a complex dose-dependent relationship between F. hepatica ES antigens and cancer cell viability. Lower concentrations (45 to 150µg/mL) of these antigens were associated with decreased cancer cell viability, whereas higher concentrations (165 to 240µg/mL) unexpectedly enhanced cell survival. Treatment with 60, 90, and 255µg/mL of ES antigen enhanced apoptosis, whereas 135 and 195µg/mL reduced apoptosis rates compared with the control group. There was a significant reduction in the population of cells at the S phase of the cell cycle at 135 and 195µg/mL of ES antigen. In comparison, an increase in the population of cells in the S phase was observed at 255µg/mL, suggesting that antigen concentration affects cell cycle progression and apoptosis. Some concentrations (195 and 255µg/mL) of ES antigen were associated with increased expression of stem cell markers, including CD133, SOX9, and β-catenin. Notably, increased production of reactive oxygen species (ROS) was observed across all concentrations. F.hepatica ES antigens may play a dual role in lung cancer cells. These antigens may possess properties that might potentially protect cancer cells from apoptosis. Conversely, in different doses, the antigens may induce cytotoxic effects, increasing cell death. This controversial data highlights the complexity of F. hepatica antigen interactions with cancer cells, which may be related to time and dose-dependency of their antigen treatment.

Fasciola hepatica (F. hepatica) is a widely prevalent trematode responsible for parasitic infections and remains a major target for control interventions worldwide. Its ability to establish chronic infection relies on complex host-parasite interactions mediated by molecular mechanisms that regulate gene expression. Among these mechanisms, microRNAs (miRNAs), a class of non-coding RNAs, act as key post-transcriptional regulators and play important roles in immune modulation during infection. These molecules are increasingly investigated as potential diagnostic biomarkers and targets for novel vaccine strategies. However, accurate miRNA quantification by qRT-PCR requires stable endogenous normalizers to control for technical and biological variability, and such normalizers have not yet been validated for fasciolosis studies in ovine plasma. Therefore, this study aims to identify stable endogenous miRNA reference genes for RT-qPCR normalization in plasma samples from sheep experimentally infected with F. hepatica during the early stages of infection. We evaluated a panel of candidate miRNAs and ranked their expression stability using RefFinder, an integrative tool that combines several algorithms, including NormFinder, the ΔCt method, geNorm, and BestKeeper. Stability analysis identified hsa-let-7c-5p, bta-let-7f, and oar-miR-16b as the most stable miRNAs across all conditions. These miRNAs showed consistent expression across samples and time points, indicating minimal susceptibility to infection-related biological variation or technical bias. They are therefore suitable endogenous normalizers for plasma miRNA quantification in early fasciolosis. The geometric mean of these three miRNAs was employed for normalization to enable accurate and reproducible relative quantification of three target miRNAs whose expression patterns are associated with distinct stages of Fasciola infection. Temporal profiling revealed an early upregulation of oar‑miR‑133‑5p, a later peak of oar‑miR‑3957‑5p, and a decreasing trend of fhe‑miR‑novel‑11‑5p. Because we obtained these expression patterns after normalization with rigorously validated stable references, they are more likely to reflect true biological dynamics rather than technical variability. Together, these findings support the stage-specific diagnostic potential of the target miRNAs and further implicate their involvement in host-parasite interactions during infection. These findings highlight the value of validated miRNAs as endogenous reference genes of plasma-based studies in ovine fasciolosis. They also improve diagnostic sensitivity and specificity by establishing a robust methodological framework for biomarker discovery, as well as for subsequent functional analyses and large-scale evaluations.

BACKGROUND: Accurate discrimination between Fasciola hepatica and Fasciola gigantica is essential for surveillance and control of fascioliasis in endemic areas. ITS1 (internal transcribed spacer 1) is a widely used molecular marker, but computational approaches to ITS-based identification must account for data quality issues in public repositories and ensure reliable decision support. PURPOSE: We developed a leakage-safe, decision-oriented pipeline for ITS1-based species identification. A curated GenBank dataset of 527 ITS1 sequences was standardized to 1,000 bp, sanitized (A/C/G/T/N only), and clustered to identify near-duplicates. Cluster-aware train/validation/test splits prevented similarity leakage. We implemented ITSformer-RC, a compact reverse-complement-invariant 1D convolutional neural network paired with a lightweight ensemble, and compared it against BLAST and k-mer logistic regression baselines. Reliability evaluation included post-hoc calibration, robustness testing under realistic perturbations (substitutions, indels, masked spans), and conformal prediction for principled abstention. METHODS: We developed a leakage-safe, decision-oriented pipeline for ITS1-based species identification. A curated GenBank dataset of 527 ITS1 sequences was standardized to 1,000 bp, sanitized (A/C/G/T/N only), and clustered to identify near-duplicates. Cluster-aware train/validation/test splits prevented similarity leakage. We implemented ITSformer-RC, a compact reverse-complement-invariant 1D convolutional neural network paired with a lightweight ensemble, and compared it against BLAST and k-mer logistic regression baselines. Reliability evaluation included post-hoc calibration, robustness testing under realistic perturbations (substitutions, indels, masked spans), and conformal prediction for principled abstention. RESULTS: Both ITSformer-RC and k-mer logistic regression achieved 100% accuracy (95% Wilson CI 0.953–1.000) on the held-out cluster-aware test split (n=78), with ROC-AUC and average precision of 1.00. Forced BLAST achieved 97.4% accuracy, while strict BLAST achieved 35.9% coverage with 100% conditional accuracy among non-abstention cases. Vector/classwise temperature scaling improved probability calibration (NLL 0.00399, ECE 1.6×10⁻⁸). Under controlled perturbations, the ensemble demonstrated robust performance across substitutions (AURC 0.9981), indels (AURC 1.0000), and masked spans (AURC 0.9902). Interpretability analysis identified five localized ITS1 windows with concentrated species-discriminative signals. CONCLUSION: The pipeline provides a reproducible, leakage-aware framework for reliable ITS1-based Fasciola identification emphasizing decision readiness and robustness over raw accuracy alone. Both deep learning and simple statistical baselines saturate accuracy on the curated benchmark, indicating strong ITS1 separability under leakage controls. Calibrated probabilities, abstention mechanisms, and robustness characterization support practical diagnostic workflows. The results are presented as internal validation on a small public dataset; external validation across geographic regions, time periods, and laboratories is required before field deployment claims can be made.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by dysbiosis of the gut microbiota. Helminth infections are known to modulate host immunity and intestinal microbial composition; however, the therapeutic use of live parasites poses safety challenges. The recombinant Fasciola hepatica fatty acid-binding protein Fh15 is a helminth-derived molecule with anti-inflammatory effects in models of septic shock and dextran sulfate sodium (DSS)-induced colitis. Whether Fh15 also influences gut microbial composition during colitis remains unknown. Male C57BL/6 mice received 4% DSS in drinking water for 7 days to induce colitis and were treated intraperitoneally with Fh15 (2 mg/kg) on days 1, 3, and 5. Fecal samples were collected on days 2, 4, and 7 for 16S rRNA gene sequencing. Standard microbiota pipelines were used to evaluate community diversity. Acute DSS treatment disrupted gut microbial diversity and community structure compared with non-colitic controls. Fh15 treatment partially restored early microbial balance by shifting microbial composition toward that of healthy mice and reducing microbial dispersion, indicating enhanced community stability despite severe dysbiosis. Although alpha diversity did not return to control levels, Fh15 mitigated the expansion of pro-inflammatory genera (Enterococcus and Turicibacter) and preserved beneficial taxa, including Adlercreutzia.

Infections with Fasciola hepatica are most prevalent in south-western Sweden, but climate change may facilitate further spread, as both the parasite and its snail host thrive in humid, mild conditions. Sheep are particularly susceptible, resulting in decreased productivity and economic losses as well as clinical disease and death. Routine field diagnosis in Sweden currently relies on sedimentation of faecal samples, although semi-quantitative PCR and coproantigen ELISA (cELISA) are available alternatives. This study presents the first Swedish comparison of diagnostic performance using composite faecal samples - each representing three ewes - collected from 73 flocks in spring (N=47) and autumn (N=58). Sedimentation, quantitative PCR (qPCR), and cELISA (evaluated at 2% and 8% optical density thresholds) were compared for their ability to detect F. hepatica. Farmers' parasite control practices were also surveyed. Concordance among methods was assessed using Cohen's kappa (κ). Sedimentation and qPCR showed substantial agreement (κ=0.72), qPCR and cELISA 8% cut-off showed considerable agreement (κ=0.61), sedimentation and cELISA showed moderate agreement (κ=0.56), while cELISA 2% cut-off naturally identified more positive samples but did not correlate with the other methods. These findings suggest that cELISA has potential as an adjunct diagnostic tool, particularly for detecting early infections, but false-negative results in pooled samples limit its suitability as a replacement for sedimentation or qPCR in routine testing. Survey responses indicated that most farmers were aware of parasite risks and followed general sampling and deworming guidelines, though specific attention to fluke control was limited.

Veterinary practitioners' perspectives on pasture-transmitted parasites in Norwegian sheep and cattle: A questionnaire-based study.

Hepatic fascioliasis is a zoonotic infection caused by Fasciola hepatica. It is underdiagnosed due to its non-specific clinical presentation and limited diagnostic tools in many healthcare settings. Human infections, though uncommon, are rising in endemic areas. We report a 40-year-old South Asian female presenting with a 3-month history of vague right hypochondrial pain, nausea, and poor appetite. Laboratory tests showed cholestatic jaundice. Abdominal ultrasound revealed gallbladder sludge and a dilated common bile duct. ERCP was performed and revealed live Fasciola hepatica worms in the biliary tree. Post-extraction, she was treated with albendazole with complete resolution of symptoms and normalization of liver biochemistry. This case highlights the importance of considering hepatic fascioliasis in patients with atypical hepatobiliary symptoms, especially in endemic regions. ERCP played a pivotal role in both diagnosis and management.

Fasciola hepatica (liver fluke) imposes major productivity and welfare costs on ruminant systems and is increasing in temperate regions such as the UK. In the absence of vaccines, control on sheep farms remains heavily dependent on flukicides, particularly triclabendazole (TCBZ), despite widespread reports of reduced efficacy and resistance. Thus, understanding how farmers perceive and manage fasciolosis risk is critical to improving sustainable control. Between October 2023 and October 2024, semi-structured, in-depth interviews were conducted with farmers from 16 sheep farms across Wales, U.K. purposively recruited through farmer networks and social media. Interviews (mean length 52 min) were audio-recorded, transcribed, and analysed using an inductive thematic approach. Despite heterogeneous farm types, farmers described fasciolosis as a "high stakes, low certainty" problem characterised by diagnostic ambiguity, limited confidence in test results, and difficulty distinguishing fluke impacts from other causes of ill-thrift. This uncertainty promoted risk-averse practises, with flukicide use functioning as "treatment as agency" and as habitual "insurance", often substituting for diagnostics due to cost, logistics, and turnaround time. Concerns about TCBZ resistance added further complexity but tended to influence behaviour after perceived treatment failure. A third theme, "making it fit", highlighted how control strategies were shaped by farm-specific geography, labour constraints, economics, and variable access to trusted veterinary support, limiting uptake of non-chemical measures and targeted treatment. Sheep farmers manage fasciolosis through pragmatic, risk-averse reliance on flukicides in the face of perceived diagnostic and advisory limitations. Interventions that improve practical access to reliable diagnostics, farm-specific risk profiling, and trusted, implementable guidance may reduce prophylactic treatment and support greater integration of non-chemical control, helping to mitigate flukicide resistance and improve sustainable fasciolosis management.

The identification of a transient receptor potential ion channel of the melastatin subfamily activated by praziquantel (TRPMPZQ) has opened new opportunities for target-based schistosomiasis drug discovery. In this study, eight new 1H-1,2,3-triazole derivatives of praziquantel (PZQ), and their synthetic intermediates, were prepared and evaluated for their schistosomicidal activity on schistosomula, juvenile, and adult Schistosoma mansoni. Their ability to activate schistosome wild-type (WT) and mutant TRPMPZQ (Sm.TRPMPZQ), as well as a schistosome TRPM channel activated by meclonazepam (Sm.TRPMMCLZ), and TRPMPZQ from Fasciola hepatica (Fh.TRPMPZQ) and Echinococcus granulosus (Eg.TRPMPZQ), was also assessed. Initial screening of schistosomula identified six compounds significantly affecting parasite motility/morphology at 25-50 μM. Compounds 3, 4, and 5e were active against juveniles by two orthogonal methods. All compounds impaired adult worm motility, with 4 being the most potent in males (EC50: 1.3-2.3 μM) and 5e being the most potent in females (EC50: 3.1-3.9 μM). Compound 5e showed the highest selectivity indexes (75 for females and 155 for males) when compared with the HepG2 human cell line. Compounds 2, 3, 4, and 5e activated WT (EC50: 0.9-13.5 μM), and mutant Sm.TRPMPZQ showing a similar activation profile to PZQ. Like PZQ, they did not activate Fh.TRPMPZQ or Sm.TRPMMCLZ at the tested concentrations but activated Eg.TRPMPZQ with similar potencies to Sm.TRPMPZQ. Molecular modeling studies suggest that the PZQ binding site on Sm.TRPMPZQ may accommodate extended substituents on position 9 of the pyrazinoisoquinoline ring due to a conformational flexibility of the Y1517 side chain. This feature could be explored to design new PZQ analogues with improved drug metabolism and pharmacokinetic properties.

Fascioliasis, a globally prevalent zoonosis, severely threatens public health and livestock security. Current diagnostic approaches, hindered by the need for sophisticated instrumentation and specialized expertise, are inadequate for on-site surveillance in resource-constrained settings. This study developed a rapid, visual detection assay for Fasciola hepatica via recombinase-aided amplification (RAA) integrated with CRISPR/Cas12b, addressing critical equipment and operational constraints. Targeting a specific mitochondrial DNA fragment of F. hepatica, recombinant plasmid standards were constructed, RAA primers and sgRNA optimized, and three detection modalities (real-time fluorescence, UV lamp, test strip) integrated. Clinical validation against PCR demonstrated 45 min turnaround time, F. hepatica-specific positivity, and real-time fluorescence sensitivity of 2.6 copies/μL. Results showed high concordance with PCR and qPCR, with substantially reduced assay duration and streamlined workflow. This highly sensitive, specific, multi-visualized method overcomes limitations of conventional techniques, offering an efficient, field-deployable tool for fascioliasis surveillance and control in grassroots and pastoral regions.