title: Zebrafish embryos as a screen for DNA methylation modifications after compound exposure.
abstract: Modified epigenetic programming early in life is proposed to underlie the development of an adverse adult phenotype, known as the Developmental Origins of Health and Disease (DOHaD) concept. Several environmental contaminants have been implicated as modifying factors of the developing epigenome. This underlines the need to investigate this newly recognized toxicological risk and systematically screen for the epigenome modifying potential of compounds. In this study, we examined the applicability of the zebrafish embryo as a screening model for DNA methylation modifications. Embryos were exposed from 0 to 72 h post fertilization (hpf) to bisphenol-A (BPA), diethylstilbestrol, 17α-ethynylestradiol, nickel, cadmium, tributyltin, arsenite, perfluoroctanoic acid, valproic acid, flusilazole, 5-azacytidine (5AC) in subtoxic concentrations. Both global and site-specific methylation was examined. Global methylation was only affected by 5AC. Genome wide locus-specific analysis was performed for BPA exposed embryos using Digital Restriction Enzyme Analysis of Methylation (DREAM), which showed minimal wide scale effects on the genome, whereas potential informative markers were not confirmed by pyrosequencing. Site-specific methylation was examined in the promoter regions of three selected genes vasa, vtg1 and cyp19a2, of which vasa (ddx4) was the most responsive. This analysis distinguished estrogenic compounds from metals by direction and sensitivity of the effect compared to embryotoxicity. In conclusion, the zebrafish embryo is a potential screening tool to examine DNA methylation modifications after xenobiotic exposure. The next step is to examine the adult phenotype of exposed embryos and to analyze molecular mechanisms that potentially link epigenetic effects and altered phenotypes, to support the DOHaD hypothesis.
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Manon C
authors.initials: MC
authors.lastname: Bouwmeester
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Sander
authors.initials: S
authors.lastname: Ruiter
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Tobias
authors.initials: T
authors.lastname: Lommelaars
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Josefine
authors.initials: J
authors.lastname: Sippel
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Hennie M
authors.initials: HM
authors.lastname: Hodemaekers
authors.affiliation: Center for Environmental Quality, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Evert-Jan
authors.initials: EJ
authors.lastname: van den Brandhof
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands.
authors.forename: Jeroen L A
authors.initials: JL
authors.lastname: Pennings
authors.affiliation: Institute for Environmental Studies (IVM), VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Jorke H
authors.initials: JH
authors.lastname: Kamstra
authors.affiliation: Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA, USA.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Jelinek
authors.affiliation: Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA, USA; Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jean-Pierre J
authors.initials: JP
authors.lastname: Issa
authors.affiliation: Institute for Environmental Studies (IVM), VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Juliette
authors.initials: J
authors.lastname: Legler
authors.affiliation: Center for Health Protection, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands. Electronic address: leo.van.der.ven@rivm.nl.
authors.forename: Leo T M
authors.initials: LT
authors.lastname: van der Ven
mesh_terms: D000818:Animals; D001559:Benzhydryl Compounds / Q000633:toxicity; D019175:DNA Methylation / Q000187:drug effects* / Q000502:physiology; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004625:Embryo, Nonmammalian; D044127:Epigenesis, Genetic / Q000187:drug effects / Q000502:physiology; D019216:Metals, Heavy / Q000633:toxicity; D010636:Phenols / Q000633:toxicity; D013256:Steroids / Q000633:toxicity; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000096:biosynthesis / Q000235:genetics*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D019216:Metals, Heavy; D010636:Phenols; D013256:Steroids; D029961:Zebrafish Proteins; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: DNA methylation; Environmental contaminant exposure; Epigenetics; Screening; Zebrafish embryo