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Dong H, Friedman KP, Filiatreault A, Thomson EM, Wade MG. A high throughput screening assay for human Thyroperoxidase inhibitors. Toxicol In Vitro 2024; 101:105946. [PMID: 39349109 DOI: 10.1016/j.tiv.2024.105946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2024] [Revised: 09/20/2024] [Accepted: 09/26/2024] [Indexed: 10/02/2024]
Abstract
Rapid, human relevant assays are needed to assess potential hazards of the many chemicals in commerce. An assay of thyroid peroxidase (TPO) inhibition, using the substrate Amplex Ultra Red, was recently adapted for human TPO (AUR-hTPO). We tested a large number (788) of chemicals through this AUR-hTPO assay and compared performance with published results from an assay using enzyme from rat thyroid microsomes (AUR-rTPO). Coded chemicals, from the US EPA ToxCast Inventory, were tested in a tiered approach: 1) Initial screening at a single concentration; 2) Potency estimation for active chemicals with multiple concentrations; 3) Screening active chemicals for the non-specific activity. The assay gave consistent results for positive chemical methimazole and several positive and negative reference chemicals. hTPO inhibition was observed for 190 chemicals reported as positive in rTPO. Of these, 158 showed no confounding activity (interference due to fluorescence or non-specific protein inhibition). Comparison of all result with rTPO data and with evidence of TPO inhibition found in the literature suggest that the current assay has a higher rate of false negative but a much lower rate of false positive compared with the rTPO screen. These findings underscore the effectiveness of the AUR assay, using hTPO enzyme from engineered cell lines, to identify moderate to strong inhibitors but some improvements may be needed to detect weak TPO inhibitors.
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Affiliation(s)
- Hongyan Dong
- Hazard Identification Division, Environmental Health Science & Research Bureau, Health Canada, Ottawa, Ontario, Canada.
| | - Katie Paul Friedman
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA.
| | - Alain Filiatreault
- Hazard Identification Division, Environmental Health Science & Research Bureau, Health Canada, Ottawa, Ontario, Canada.
| | - Errol M Thomson
- Hazard Identification Division, Environmental Health Science & Research Bureau, Health Canada, Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
| | - Michael G Wade
- Hazard Identification Division, Environmental Health Science & Research Bureau, Health, Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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Gundacker C, Audouze K, Widhalm R, Granitzer S, Forsthuber M, Jornod F, Wielsøe M, Long M, Halldórsson TI, Uhl M, Bonefeld-Jørgensen EC. Reduced Birth Weight and Exposure to Per- and Polyfluoroalkyl Substances: A Review of Possible Underlying Mechanisms Using the AOP-HelpFinder. TOXICS 2022; 10:toxics10110684. [PMID: 36422892 PMCID: PMC9699222 DOI: 10.3390/toxics10110684] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/04/2022] [Accepted: 11/07/2022] [Indexed: 05/14/2023]
Abstract
Prenatal exposure to per- and polyfluorinated substances (PFAS) may impair fetal growth. Our knowledge of the underlying mechanisms is incomplete. We used the Adverse Outcome Pathway (AOP)-helpFinder tool to search PubMed for studies published until March 2021 that examined PFAS exposure in relation to birth weight, oxidative stress, hormones/hormone receptors, or growth signaling pathways. Of these 1880 articles, 106 experimental studies remained after abstract screening. One clear finding is that PFAS are associated with oxidative stress in in vivo animal studies and in vitro studies. It appears that PFAS-induced reactive-oxygen species (ROS) generation triggers increased peroxisome proliferator-activated receptor (PPAR)γ expression and activation of growth signaling pathways, leading to hyperdifferentiation of pre-adipocytes. Fewer proliferating pre-adipocytes result in lower adipose tissue weight and in this way may reduce birth weight. PFAS may also impair fetal growth through endocrine effects. Estrogenic effects have been noted in in vivo and in vitro studies. Overall, data suggest thyroid-damaging effects of PFAS affecting thyroid hormones, thyroid hormone gene expression, and histology that are associated in animal studies with decreased body and organ weight. The effects of PFAS on the complex relationships between oxidative stress, endocrine system function, adipogenesis, and fetal growth should be further explored.
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Affiliation(s)
- Claudia Gundacker
- Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
- Correspondence: ; Tel.: +43-1-40160-56503
| | - Karine Audouze
- Unit T3S, Université Paris Cité, Inserm U1124, 75006 Paris, France
| | - Raimund Widhalm
- Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Sebastian Granitzer
- Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Forsthuber
- Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Florence Jornod
- Unit T3S, Université Paris Cité, Inserm U1124, 75006 Paris, France
| | - Maria Wielsøe
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
| | - Manhai Long
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
| | - Thórhallur Ingi Halldórsson
- Faculty of Food Science and Nutrition, University of Iceland, 102 Reykjavík, Iceland
- Department of Epidemiology Research, Statens Serum Institut, 2300 Copenhagen, Denmark
| | - Maria Uhl
- Environment Agency Austria, 1090 Vienna, Austria
| | - Eva Cecilie Bonefeld-Jørgensen
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
- Greenland Center for Health Research, Greenland University, Nuuk 3905, Greenland
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Moroni L, Barbaro F, Caiment F, Coleman O, Costagliola S, Di Conza G, Elviri L, Giselbrecht S, Krause C, Mota C, Nazzari M, Pennington SR, Ringwald A, Sandri M, Thomas S, Waddington J, Toni R. SCREENED: A Multistage Model of Thyroid Gland Function for Screening Endocrine-Disrupting Chemicals in a Biologically Sex-Specific Manner. Int J Mol Sci 2020; 21:E3648. [PMID: 32455722 PMCID: PMC7279272 DOI: 10.3390/ijms21103648] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/04/2020] [Accepted: 05/14/2020] [Indexed: 12/12/2022] Open
Abstract
Endocrine disruptors (EDs) are chemicals that contribute to health problems by interfering with the physiological production and target effects of hormones, with proven impacts on a number of endocrine systems including the thyroid gland. Exposure to EDs has also been associated with impairment of the reproductive system and incidence in occurrence of obesity, type 2 diabetes, and cardiovascular diseases during ageing. SCREENED aims at developing in vitro assays based on rodent and human thyroid cells organized in three different three-dimensional (3D) constructs. Due to different levels of anatomical complexity, each of these constructs has the potential to increasingly mimic the structure and function of the native thyroid gland, ultimately achieving relevant features of its 3D organization including: 1) a 3D organoid based on stem cell-derived thyrocytes, 2) a 3D organoid based on a decellularized thyroid lobe stromal matrix repopulated with stem cell-derived thyrocytes, and 3) a bioprinted organoid based on stem cell-derived thyrocytes able to mimic the spatial and geometrical features of a native thyroid gland. These 3D constructs will be hosted in a modular microbioreactor equipped with innovative sensing technology and enabling precise control of cell culture conditions. New superparamagnetic biocompatible and biomimetic particles will be used to produce "magnetic cells" to support precise spatiotemporal homing of the cells in the 3D decellularized and bioprinted constructs. Finally, these 3D constructs will be used to screen the effect of EDs on the thyroid function in a unique biological sex-specific manner. Their performance will be assessed individually, in comparison with each other, and against in vivo studies. The resulting 3D assays are expected to yield responses to low doses of different EDs, with sensitivity and specificity higher than that of classical 2D in vitro assays and animal models. Supporting the "Adverse Outcome Pathway" concept, proteogenomic analysis and biological computational modelling of the underlying mode of action of the tested EDs will be pursued to gain a mechanistic understanding of the chain of events from exposure to adverse toxic effects on thyroid function. For future uptake, SCREENED will engage discussion with relevant stakeholder groups, including regulatory bodies and industry, to ensure that the assays will fit with purposes of ED safety assessment. In this project review, we will briefly discuss the current state of the art in cellular assays of EDs and how our project aims at further advancing the field of cellular assays for EDs interfering with the thyroid gland.
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Affiliation(s)
- Lorenzo Moroni
- MERLN Institute for Technology-Inspired Regenerative Medicine, Department of Complex Tissue Regeneration, Maastricht University, 6229ET Maastricht, The Netherlands;
| | - Fulvio Barbaro
- Department of Medicine and Surgery—DIMEC, Unit of Biomedical, Biotechnological and Translational Sciences (S.BI.BI.T.), Laboratory of Regenerative Morphology and Bioartificial Structures (Re.Mo.Bio.S. Lab.), University of Parma, 43121 Parma, Italy; (F.B.); (G.D.C.); (R.T.)
| | - Florian Caiment
- Toxicogenomics, Maastricht University, 6229ET Maastricht, The Netherlands; (F.C.); (M.N.)
| | - Orla Coleman
- Atturos Ltd., c/o Conway Research Institute, University College Dublin, Dublin 4, Ireland; (O.C.); (S.R.P.)
| | - Sabine Costagliola
- Institute of Interdisciplinary Research in Molecular Human Biology (IRIBHM), Université Libre de Bruxelles, 1050 Brussels, Belgium;
| | - Giusy Di Conza
- Department of Medicine and Surgery—DIMEC, Unit of Biomedical, Biotechnological and Translational Sciences (S.BI.BI.T.), Laboratory of Regenerative Morphology and Bioartificial Structures (Re.Mo.Bio.S. Lab.), University of Parma, 43121 Parma, Italy; (F.B.); (G.D.C.); (R.T.)
| | - Lisa Elviri
- Food and Drug Department, University of Parma, 43121 Parma, Italy;
| | - Stefan Giselbrecht
- MERLN Institute for Technology-Inspired Regenerative Medicine, Department of Instruct Biomaterials Engineering, Maastricht University, 6229ET Maastricht, The Netherlands;
| | | | - Carlos Mota
- MERLN Institute for Technology-Inspired Regenerative Medicine, Department of Complex Tissue Regeneration, Maastricht University, 6229ET Maastricht, The Netherlands;
| | - Marta Nazzari
- Toxicogenomics, Maastricht University, 6229ET Maastricht, The Netherlands; (F.C.); (M.N.)
| | - Stephen R. Pennington
- Atturos Ltd., c/o Conway Research Institute, University College Dublin, Dublin 4, Ireland; (O.C.); (S.R.P.)
- UCD Conway Institute, School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland;
| | | | - Monica Sandri
- Institute of Science and Technology for Ceramics, National Research Council of Italy (ISTEC-CNR), 48018 Faenza, Italy;
| | - Simon Thomas
- Cyprotex Discovery Ltd., No. 24 Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK;
| | - James Waddington
- UCD Conway Institute, School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland;
| | - Roberto Toni
- Department of Medicine and Surgery—DIMEC, Unit of Biomedical, Biotechnological and Translational Sciences (S.BI.BI.T.), Laboratory of Regenerative Morphology and Bioartificial Structures (Re.Mo.Bio.S. Lab.), University of Parma, 43121 Parma, Italy; (F.B.); (G.D.C.); (R.T.)
- Division of Endocrinology, Diabetes, and Metabolism, Tufts Medical Center - Tufts University School of Medicine, Boston, MA 02111, USA
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An overview of omics approaches to characterize the effect of perfluoroalkyl substances in environmental health. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2018.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Krause M, Frederiksen H, Sundberg K, Jørgensen FS, Jensen LN, Nørgaard P, Jørgensen C, Ertberg P, Petersen JH, Feldt-Rasmussen U, Juul A, Drzewiecki KT, Skakkebaek NE, Andersson AM. Maternal exposure to UV filters: associations with maternal thyroid hormones, IGF-I/IGFBP3 and birth outcomes. Endocr Connect 2018; 7:334-346. [PMID: 29362228 PMCID: PMC5820990 DOI: 10.1530/ec-17-0375] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 01/23/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Several chemical UV filters/absorbers ('UV filters' hereafter) have endocrine-disrupting properties in vitro and in vivo. Exposure to these chemicals, especially during prenatal development, is of concern. OBJECTIVES To examine maternal exposure to UV filters, associations with maternal thyroid hormone, with growth factor concentrations as well as to birth outcomes. METHODS Prospective study of 183 pregnant women with 2nd trimester serum and urine samples available. Maternal concentrations of the chemical UV filters benzophenone-1 (BP-1) and benzophenone-3 (BP-3) in urine and 4-hydroxy-benzophenone (4-HBP) in serum were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The relationships between 2nd trimester maternal concentrations of the three chemical UV filters and maternal serum concentrations of thyroid hormones and growth factors, as well as birth outcomes (weight, height, and head and abdominal circumferences) were examined. RESULTS Positive associations between maternal serum concentrations of 4-HBP and triiodothyronine (T3), thyroxine (T4), insulin-like growth factor I (IGF-I) and its binding protein IGFBP3 were observed in mothers carrying male fetuses. Male infants of mothers in the middle 4-HBP exposure group had statistically significantly lower weight and shorter head and abdominal circumferences at birth compared to the low exposure group. CONCLUSIONS Widespread exposure of pregnant women to chemical UV filters and the possible impact on maternal thyroid hormones and growth factors, and on fetal growth, calls for further studies on possible long-term consequences of the exposure to UV filters on fetal development and children's health.
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Affiliation(s)
- M Krause
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - H Frederiksen
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - K Sundberg
- Center of Fetal Medicine and PregnancyDepartment of Obstetrics, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - F S Jørgensen
- Fetal Medicine UnitDepartment of Obstetrics and Gynecology, Copenhagen University Hospital, Hvidovre, Denmark
| | - L N Jensen
- Center of Fetal Medicine and PregnancyDepartment of Obstetrics, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - P Nørgaard
- Fetal Medicine UnitDepartment of Obstetrics and Gynecology, Copenhagen University Hospital, Hvidovre, Denmark
| | - C Jørgensen
- Center of Fetal Medicine and PregnancyDepartment of Obstetrics, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - P Ertberg
- Fetal Medicine UnitDepartment of Obstetrics and Gynecology, Copenhagen University Hospital, Hvidovre, Denmark
| | - J H Petersen
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Section of BiostatisticsFaculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - U Feldt-Rasmussen
- Department of EndocrinologyRigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - A Juul
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - K T Drzewiecki
- Department of Plastic SurgeryBreast Surgery and Burns Treatment, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - N E Skakkebaek
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - A M Andersson
- Department of Growth and Reproduction & International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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Wegner S, Browne P, Dix D. Identifying reference chemicals for thyroid bioactivity screening. Reprod Toxicol 2016; 65:402-413. [PMID: 27589887 DOI: 10.1016/j.reprotox.2016.08.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 08/19/2016] [Accepted: 08/29/2016] [Indexed: 12/20/2022]
Abstract
Reference chemicals were selected based on thyroid bioactivity in 'Tier 1' screening assays used by the U.S. EPA's Endocrine Disruptor Screening Program. Active reference chemicals had significant effects on thyroid-responsive endpoints in the amphibian metamorphosis assay, and the male and female pubertal rat assays. In the absence of thyroid weight or histopathological effects, additional published studies providing mechanistic data on thyroid activity were required for active chemicals. Inactive reference chemicals had no significant effects on thyroid-responsive endpoints in Tier 1 assays, or in amphibian or rodent studies from several online databases. The 34 reference chemicals (29 active and five inactive) will be useful for performance-based validation of alternative, high throughput screening assays for thyroid bioactivity.
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Affiliation(s)
- Susanna Wegner
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN, United States.
| | - Patience Browne
- Office of Science Coordination and Policy (OSCP), Office of Chemical Safety and Pollution Prevention, U.S. EPA, Washington, D.C., United States
| | - David Dix
- Office of Science Coordination and Policy (OSCP), Office of Chemical Safety and Pollution Prevention, U.S. EPA, Washington, D.C., United States
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Phthalates Are Metabolised by Primary Thyroid Cell Cultures but Have Limited Influence on Selected Thyroid Cell Functions In Vitro. PLoS One 2016; 11:e0151192. [PMID: 26985823 PMCID: PMC4795645 DOI: 10.1371/journal.pone.0151192] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 02/24/2016] [Indexed: 11/19/2022] Open
Abstract
Phthalates are plasticisers added to a wide variety of products, resulting in measurable exposure of humans. They are suspected to disrupt the thyroid axis as epidemiological studies suggest an influence on the peripheral thyroid hormone concentration. The mechanism is still unknown as only few in vitro studies within this area exist. The aim of the present study was to investigate the influence of three phthalate diesters (di-ethyl phthalate, di-n-butyl phthalate (DnBP), di-(2-ethylhexyl) phthalate (DEHP)) and two monoesters (mono-n-butyl phthalate and mono-(2-ethylhexyl) phthalate (MEHP)) on the differentiated function of primary human thyroid cell cultures. Also, the kinetics of phthalate metabolism were investigated. DEHP and its monoester, MEHP, both had an inhibitory influence on 3'-5'-cyclic adenosine monophosphate secretion from the cells, and MEHP also on thyroglobulin (Tg) secretion from the cells. Results of the lactate dehydrogenase-measurements indicated that the MEHP-mediated influence was caused by cell death. No influence on gene expression of thyroid specific genes (Tg, thyroid peroxidase, sodium iodine symporter and thyroid stimulating hormone receptor) by any of the investigated diesters could be demonstrated. All phthalate diesters were metabolised to the respective monoester, however with a fall in efficiency for high concentrations of the larger diesters DnBP and DEHP. In conclusion, human thyroid cells were able to metabolise phthalates but this phthalate-exposure did not appear to substantially influence selected functions of these cells.
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Sriphrapradang C, Chailurkit LO, Aekplakorn W, Ongphiphadhanakul B. Association between bisphenol A and abnormal free thyroxine level in men. Endocrine 2013; 44:441-7. [PMID: 23377699 DOI: 10.1007/s12020-013-9889-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 01/19/2013] [Indexed: 10/27/2022]
Abstract
Bisphenol A (BPA) is a chemical that is used in a variety of consumer products, and exposure to BPA is widespread among the general population. Recent studies have suggested that BPA may affect the thyroid and related pathways. However, human studies are still limited. The aim of this study was to determine the relationship between BPA exposure and thyroid function. We obtained survey data and blood samples from The Thai National Health Examination Survey IV 2009, a nationally representative cross-sectional survey using a multistage, stratified sampling of the Thai population. A total of 2,340 subjects aged 18-94 years were sampled for the present study. Serum BPA, TSH, FT4, and related covariates were measured. BPA was log-transformed prior to analysis. BPA was detected in 52.8 % of serum samples with a median concentration of 0.33 (range 0-66.91) ng/mL. We excluded subjects who tested positive for thyroid autoantibody and then stratified the remaining subjects by gender; the analysis showed a significantly negative correlation between serum BPA and FT4 levels in males (r = -0.14, P < 0.001). In contrast, no association was observed in females. BPA was not associated with TSH in either gender. This gender-related discrepancy is possibly related to androgen-related differences in the metabolism of BPA. Our preliminary results provide evidence of a negative association between BPA and FT4 levels. Additional detailed studies are needed to investigate the temporal relationship and potential public health implications of such an association.
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Affiliation(s)
- Chutintorn Sriphrapradang
- Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
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9
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Murk AJ, Rijntjes E, Blaauboer BJ, Clewell R, Crofton KM, Dingemans MML, Furlow JD, Kavlock R, Köhrle J, Opitz R, Traas T, Visser TJ, Xia M, Gutleb AC. Mechanism-based testing strategy using in vitro approaches for identification of thyroid hormone disrupting chemicals. Toxicol In Vitro 2013; 27:1320-46. [PMID: 23453986 DOI: 10.1016/j.tiv.2013.02.012] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 02/07/2013] [Accepted: 02/18/2013] [Indexed: 11/16/2022]
Abstract
The thyroid hormone (TH) system is involved in several important physiological processes, including regulation of energy metabolism, growth and differentiation, development and maintenance of brain function, thermo-regulation, osmo-regulation, and axis of regulation of other endocrine systems, sexual behaviour and fertility and cardiovascular function. Therefore, concern about TH disruption (THD) has resulted in strategies being developed to identify THD chemicals (THDCs). Information on potential of chemicals causing THD is typically derived from animal studies. For the majority of chemicals, however, this information is either limited or unavailable. It is also unlikely that animal experiments will be performed for all THD relevant chemicals in the near future for ethical, financial and practical reasons. In addition, typical animal experiments often do not provide information on the mechanism of action of THDC, making it harder to extrapolate results across species. Relevant effects may not be identified in animal studies when the effects are delayed, life stage specific, not assessed by the experimental paradigm (e.g., behaviour) or only occur when an organism has to adapt to environmental factors by modulating TH levels. Therefore, in vitro and in silico alternatives to identify THDC and quantify their potency are needed. THDC have many potential mechanisms of action, including altered hormone production, transport, metabolism, receptor activation and disruption of several feed-back mechanisms. In vitro assays are available for many of these endpoints, and the application of modern '-omics' technologies, applicable for in vivo studies can help to reveal relevant and possibly new endpoints for inclusion in a targeted THDC in vitro test battery. Within the framework of the ASAT initiative (Assuring Safety without Animal Testing), an international group consisting of experts in the areas of thyroid endocrinology, toxicology of endocrine disruption, neurotoxicology, high-throughput screening, computational biology, and regulatory affairs has reviewed the state of science for (1) known mechanisms for THD plus examples of THDC; (2) in vitro THD tests currently available or under development related to these mechanisms; and (3) in silico methods for estimating the blood levels of THDC. Based on this scientific review, the panel has recommended a battery of test methods to be able to classify chemicals as of less or high concern for further hazard and risk assessment for THD. In addition, research gaps and needs are identified to be able to optimize and validate the targeted THD in vitro test battery for a mechanism-based strategy for a decision to opt out or to proceed with further testing for THD.
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Affiliation(s)
- AlberTinka J Murk
- Wageningen University, Sub-department of Toxicology, Tuinlaan 5, 6703 HE Wageningen, The Netherlands.
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10
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Song M, Song MK, Choi HS, Ryu JC. Monitoring of deiodinase deficiency based on transcriptomic responses in SH-SY5Y cells. Arch Toxicol 2013; 87:1103-13. [PMID: 23397585 DOI: 10.1007/s00204-013-1018-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 01/22/2013] [Indexed: 12/20/2022]
Abstract
Iodothyronine deiodinase types I, II, and III (D1, D2, and D3, respectively), which constitute a family of selenoenzymes, activate and inactivate thyroid hormones through the removal of specific iodine moieties from thyroxine and its derivatives. These enzymes are important in the biological effects mediated by thyroid hormones. The expression of activating and inactivating deiodinases plays a critical role in a number of cell systems, including the neuronal system, during development as well as in adult vertebrates. To investigate deiodinase-disrupting chemicals based on transcriptomic responses, we examined differences in gene expression profiles between T3-treated and deiodinase-knockdown SH-SY5Y cells using microarray analysis and quantitative real-time RT-PCR. A total of 1,558 genes, consisting of 755 upregulated and 803 downregulated genes, were differentially expressed between the T3-treated and deiodinase-knockdown cells. The expression levels of 10 of these genes (ID2, ID3, CCL2, TBX3, TGOLN2, C1orf71, ZNF676, GULP1, KLF9, and ITGB5) were altered by deiodinase-disrupting chemicals (2,3,7,8-tetrachlorodibenzo-p-dioxin, polychlorinated biphenyls, propylthiouracil, iodoacetic acid, methylmercury, β-estradiol, methimazole, 3-methylcholanthrene, aminotriazole, amiodarone, cadmium chloride, dimethoate, fenvalerate, octylmethoxycinnamate, iopanoic acid, methoxychlor, and 4-methylbenzylidene-camphor). These genes are potential biomarkers for detecting deiodinase deficiency and predicting their effects on thyroid hormone production.
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Affiliation(s)
- Mee Song
- Cellular and Molecular Toxicology Laboratory, Center for Integrated Risk Research, Korea Institute of Science and Technology (KIST), P.O. Box 131, Cheongryang, Seoul, Republic of Korea
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Song M, Kim YJ, Park YK, Ryu JC. Changes in thyroid peroxidase activity in response to various chemicals. ACTA ACUST UNITED AC 2012; 14:2121-6. [DOI: 10.1039/c2em30106g] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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