title: Zebrafish eleutheroembryos provide a suitable vertebrate model for screening chemicals that impair thyroid hormone synthesis.
abstract: Thyroxine-immunofluorescence quantitative disruption test (TIQDT) was designed to provide a simple, rapid, alternative bioassay for assessing the potential of chemical pollutants and drugs to disrupt thyroid gland function. This study demonstrated that zebrafish eleutheroembryos provided a suitable vertebrate model, not only for screening the potential thyroid disrupting effect of molecules, but also for estimating the potential hazards associated with exposure to chemicals directly impairing thyroxine (T4) synthesis. Amitrole, potassium perchlorate, potassium thiocyanate, methimazole (MMI), phloroglucinol, 6-propyl-2-thiouracil, ethylenethiourea, benzophenone-2, resorcinol, pyrazole, sulfamethoxazole, sodium bromide, mancozeb, and genistein were classified as thyroid gland function disruptors. Concordance between TIQDT on zebrafish and mammalian published data was very high and the physiological relevance of T4-intrafollicular content was clearly higher than regulation at the transcriptional level of tg or slc5a5. Moreover, concentration-response analysis provided information about the thyroid disrupting potency and hazard of selected positive compounds. Finally, the effect of perchlorate, but not MMI, was completely rescued by low-micromolar amounts of iodide. TIQDT performed on zebrafish eleutheroembryos is an alternative whole-organism screening assay that provides relevant information for environmental and human risk assessments.
authors.affiliation: Institute of Environmental Assessment and Water Research, IDÆA-CSIC, Jordi Girona 18, 08034 Barcelona, Spain.
authors.forename: Benedicte
authors.initials: B
authors.lastname: Thienpont
authors.forename: Angèle
authors.initials: A
authors.lastname: Tingaud-Sequeira
authors.forename: Eva
authors.initials: E
authors.lastname: Prats
authors.forename: Carlos
authors.initials: C
authors.lastname: Barata
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Babin
authors.forename: Demetrio
authors.initials: D
authors.lastname: Raldúa
mesh_terms: D000818:Animals; D013956:Antithyroid Agents / Q000494:pharmacology*; D001681:Biological Assay / Q000379:methods; D002648:Child; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D007454:Iodides / Q000378:metabolism; D008713:Methimazole / Q000494:pharmacology; D023421:Models, Animal; D010472:Perchlorates / Q000494:pharmacology; D017680:Potassium Compounds / Q000494:pharmacology; D011247:Pregnancy; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000187:drug effects* / Q000378:metabolism*; D013963:Thyroid Hormones / Q000096:biosynthesis*; D014874:Water Pollutants, Chemical / Q000494:pharmacology*; D015027:Zebrafish / Q000196:embryology / Q000378:metabolism
chemical_list: D013956:Antithyroid Agents; D007454:Iodides; D010472:Perchlorates; D017680:Potassium Compounds; D013963:Thyroid Hormones; D014874:Water Pollutants, Chemical; C009006:potassium perchlorate; D008713:Methimazole