Abstract
The foodborne trematodiases refer to a cluster of zoonotic neglected tropical diseases caused by trematodes, with transmission involving ingestion of contaminated plants, fishes, and crustaceans. Over 40 million people are infected with foodborne trematodes and 750 million are at risk of infection. From a public health point of view, important species include Clonorchis sinensis, Opisthorchis viverrini, Opisthorchis felineus, Fasciola hepatica, and Fasciola gigantica. Infection with C. sinensis and O. viverrini is classified as a group 1 biological carcinogen and a major risk factor for cholangiocarcinoma. The carcinogenic potential of the infection with O. felineus is less clear but recent biochemical and histopathological findings revealed that opisthorchiasis felinea also fits this pattern. By contrast, evidence of carcinogenic potential of infection with F. hepatica or F. gigantica, close phylogenetics relatives of Opisthorchis, is less certain. Oxysterols have been essentially described in animal model of opisthorchiasis and associated cholangiocarcinoma. Several oxysterol-like metabolites have been detected not only on developmental stages of O. viverrini and O. felineus but also on biofluids from experimentally infected hamsters as products of the activities of the liver flukes. These sterol derivatives are metabolized to active quinones that can modify host DNA. We have postulated that helminth parasite–associated sterols might induce tumor-like phenotypes in biliary epithelia, the cells of origin of liver fluke infection–associated cholangiocarcinoma, through the formation of DNA adducts, dysregulation of apoptosis, and other homeostatic pathways. Here we review, interpret, and discuss findings of oxysterol-like metabolites detected in liver flukes and their role in carcinogenesis, aiming to enhance understanding the pathogenesis of foodborne trematodiasis caused by Opisthorchis and Fasciola species. In future, further investigations will be necessary in order to comprehend relationship between liver flukes’ oxysterols and their role in infection-associated diseases in humans.
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Abbreviations
- BilIN:
-
Biliary intraepithelial neoplasia (BilIN)
- CCA:
-
Cholangiocarcinoma
- CYP:
-
Cytochrome P450
- LC-MS/MS:
-
Liquid chromatography mass spectrometry
- MS:
-
Mass spectra (MS)
- NTD:
-
Neglected tropical diseases
- ROS/RNS:
-
Reactive oxygen species/reactive nitrative species
- WHO:
-
World Health Organization
- 8-oxodG:
-
8-Oxo-7,8-hydro-2′-deoxyguanosine
- 8-NG:
-
8-Nitroguanine
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Acknowledgments
NV thanks FCT by IF position and Fundação Manuel António da Mota (FMAM, Portugal) by support Nuno Vale Lab. PJB acknowledges support from award CA164719 from the National Cancer Institute, National Institutes of Health (NIH), USA. The contents of this report are solely the responsibility of the authors and do not necessarily represent the official views of the FCT, FMAM, or the NIH.
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This work was financed by FEDER - Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 - Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia, in the framework of the project “Institute for Research and Innovation in Health Sciences” (POCI-01-0145-FEDER-007274). This work was also financed by FCT and FEDER (European Union), through project IF/00092/2014/CP1255/CT0004.
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Vale, N., Gouveia, M.J., Gärtner, F. et al. Oxysterols of helminth parasites and pathogenesis of foodborne hepatic trematodiasis caused by Opisthorchis and Fasciola species. Parasitol Res 119, 1443–1453 (2020). https://doi.org/10.1007/s00436-020-06640-4
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DOI: https://doi.org/10.1007/s00436-020-06640-4