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Pannetier P, Gölz L, Pissarreira Mendes Fagundes MT, Knörr S, Behnstedt L, Coordes S, Matthiessen P, Morthorst JE, Vergauwen L, Knapen D, Holbech H, Braunbeck T, Baumann L. Development of the integrated fish endocrine disruptor test (iFEDT)-Part A: Merging of existing fish test guidelines. Integr Environ Assess Manag 2024; 20:817-829. [PMID: 37483114 DOI: 10.1002/ieam.4819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/21/2023] [Accepted: 07/20/2023] [Indexed: 07/25/2023]
Abstract
There has been increasing interest in endocrine-disrupting chemicals (EDCs) among scientists and public authorities over the last 30 years, notably because of their wide use and the increasing evidence of detrimental effects on humans and the environment. However, test systems for the detection of potential EDCs as well as testing strategies still require optimization. Thus, the aim of the present project was the development of an integrated test protocol that merges the existing OECD test guidelines (TGs) 229 (fish short-term reproduction assay) and 234 (fish sexual development test) and implements thyroid-related endpoints for fish. The integrated fish endocrine disruptor test (iFEDT) represents a comprehensive approach for fish testing, which covers reproduction, early development, and sexual differentiation, and will thus allow the identification of multiple endocrine-disruptive effects in fish. Using zebrafish (Danio rerio) as a model organism, two exposure tests were performed with well-studied EDCs: 6-propyl-2-thiouracil (PTU), an inhibitor of thyroid hormone synthesis, and 17α-ethinylestradiol (EE2), an estrogen receptor agonist. In part A of this article, the effects of PTU and EE2 on established endpoints of the two existing TGs are reported, whereas part B focuses on the novel thyroid-related endpoints. Results of part A document that, as expected, both PTU and EE2 had strong effects on various endocrine-related endpoints in zebrafish and their offspring. Merging of TGs 229 and 234 proved feasible, and all established biomarkers and endpoints were responsive as expected, including reproductive and morphometric changes (PTU and EE2), vitellogenin levels, sex ratio, gonad maturation, and histopathology (only for EE2) of different life stages. A validation of the iFEDT with other well-known EDCs will allow verification of the sensitivity and usability and confirm its capacity to improve the existing testing strategy for EDCs in fish. Integr Environ Assess Manag 2024;20:817-829. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
- Pauline Pannetier
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
- Laboratoire de Ploufragan-Plouzané-Niort, Site de Plouzané, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail, Plouzané, France
| | - Lisa Gölz
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | | | - Susanne Knörr
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Laura Behnstedt
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Sara Coordes
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | | | - Jane E Morthorst
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Lucia Vergauwen
- Department of Veterinary Sciences, Veterinary Physiology and Biochemistry, Zebrafishlab, University of Antwerp, Wilrijk, Belgium
| | - Dries Knapen
- Department of Veterinary Sciences, Veterinary Physiology and Biochemistry, Zebrafishlab, University of Antwerp, Wilrijk, Belgium
| | - Henrik Holbech
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Thomas Braunbeck
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Lisa Baumann
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
- Amsterdam Institute for Life and Environment (A-LIFE), Section Environmental Health and Toxicology, Vrije Universiteit Amsterdam, HV Amsterdam, The Netherlands
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Ramhøj L, Axelstad M, Baert Y, Cañas-Portilla AI, Chalmel F, Dahmen L, De La Vieja A, Evrard B, Haigis AC, Hamers T, Heikamp K, Holbech H, Iglesias-Hernandez P, Knapen D, Marchandise L, Morthorst JE, Nikolov NG, Nissen ACVE, Oelgeschlaeger M, Renko K, Rogiers V, Schüürmann G, Stinckens E, Stub MH, Torres-Ruiz M, Van Duursen M, Vanhaecke T, Vergauwen L, Wedebye EB, Svingen T. New approach methods to improve human health risk assessment of thyroid hormone system disruption-a PARC project. Front Toxicol 2023; 5:1189303. [PMID: 37265663 PMCID: PMC10229837 DOI: 10.3389/ftox.2023.1189303] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 05/05/2023] [Indexed: 06/03/2023] Open
Abstract
Current test strategies to identify thyroid hormone (TH) system disruptors are inadequate for conducting robust chemical risk assessment required for regulation. The tests rely heavily on histopathological changes in rodent thyroid glands or measuring changes in systemic TH levels, but they lack specific new approach methodologies (NAMs) that can adequately detect TH-mediated effects. Such alternative test methods are needed to infer a causal relationship between molecular initiating events and adverse outcomes such as perturbed brain development. Although some NAMs that are relevant for TH system disruption are available-and are currently in the process of regulatory validation-there is still a need to develop more extensive alternative test batteries to cover the range of potential key events along the causal pathway between initial chemical disruption and adverse outcomes in humans. This project, funded under the Partnership for the Assessment of Risk from Chemicals (PARC) initiative, aims to facilitate the development of NAMs that are specific for TH system disruption by characterizing in vivo mechanisms of action that can be targeted by in embryo/in vitro/in silico/in chemico testing strategies. We will develop and improve human-relevant in vitro test systems to capture effects on important areas of the TH system. Furthermore, we will elaborate on important species differences in TH system disruption by incorporating non-mammalian vertebrate test species alongside classical laboratory rat species and human-derived in vitro assays.
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Affiliation(s)
- Louise Ramhøj
- Research Group for Molecular and Reproductive Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Marta Axelstad
- Research Group for Molecular and Reproductive Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Yoni Baert
- Department In Vitro Toxicology and Dermato-cosmetology (IVTD), Vrije Universiteit Brussel, Jette, Belgium
| | - Ana I. Cañas-Portilla
- Environmental Toxicology Unit from National Center for Environmental Health (CNSA), Endocrine Tumor Unit from UFIEC, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Frédéric Chalmel
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), Rennes, France
| | - Lars Dahmen
- Department Experimental Toxicology and ZEBET, German Centre for the Protection of Laboratory Animals (Bf3R), German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Antonio De La Vieja
- Environmental Toxicology Unit from National Center for Environmental Health (CNSA), Endocrine Tumor Unit from UFIEC, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Bertrand Evrard
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), Rennes, France
| | - Ann-Cathrin Haigis
- Zebrafishlab, Veterinary Physiology and Biochemistry, Department of Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
| | - Timo Hamers
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Kim Heikamp
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Centre for Health Protection (GZB), National Institute for Public Health and the Environment (RIVM), Bilthoven, Netherlands
| | - Henrik Holbech
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Patricia Iglesias-Hernandez
- Environmental Toxicology Unit from National Center for Environmental Health (CNSA), Endocrine Tumor Unit from UFIEC, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Dries Knapen
- Zebrafishlab, Veterinary Physiology and Biochemistry, Department of Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
| | - Lorna Marchandise
- Department In Vitro Toxicology and Dermato-cosmetology (IVTD), Vrije Universiteit Brussel, Jette, Belgium
| | - Jane E. Morthorst
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Nikolai Georgiev Nikolov
- Group for Chemical Risk Assessment and GMO, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ana C. V. E. Nissen
- Group for Chemical Risk Assessment and GMO, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Michael Oelgeschlaeger
- Department Experimental Toxicology and ZEBET, German Centre for the Protection of Laboratory Animals (Bf3R), German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Kostja Renko
- Department Experimental Toxicology and ZEBET, German Centre for the Protection of Laboratory Animals (Bf3R), German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Vera Rogiers
- Department In Vitro Toxicology and Dermato-cosmetology (IVTD), Vrije Universiteit Brussel, Jette, Belgium
| | - Gerrit Schüürmann
- UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Evelyn Stinckens
- Zebrafishlab, Veterinary Physiology and Biochemistry, Department of Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
| | - Mette H. Stub
- Research Group for Molecular and Reproductive Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Monica Torres-Ruiz
- Environmental Toxicology Unit from National Center for Environmental Health (CNSA), Endocrine Tumor Unit from UFIEC, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Majorie Van Duursen
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Tamara Vanhaecke
- Department In Vitro Toxicology and Dermato-cosmetology (IVTD), Vrije Universiteit Brussel, Jette, Belgium
| | - Lucia Vergauwen
- Zebrafishlab, Veterinary Physiology and Biochemistry, Department of Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
| | - Eva Bay Wedebye
- Group for Chemical Risk Assessment and GMO, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Terje Svingen
- Research Group for Molecular and Reproductive Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
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Morthorst JE, Holbech H, De Crozé N, Matthiessen P, LeBlanc GA. Thyroid-like hormone signaling in invertebrates and its potential role in initial screening of thyroid hormone system disrupting chemicals. Integr Environ Assess Manag 2023; 19:63-82. [PMID: 35581168 PMCID: PMC10083991 DOI: 10.1002/ieam.4632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/30/2022] [Accepted: 05/12/2022] [Indexed: 05/07/2023]
Abstract
This review examines the presence and evolution of thyroid-like systems in selected aquatic invertebrates to determine the potential use of these organisms in screens for vertebrate thyroid hormone axis disrupting chemicals (THADCs). Such a screen might support the phasing out of some vertebrate testing. Although arthropods including crustaceans do not contain a functional thyroid signaling system, elements of such a system exist in the aquatic phyla mollusks, echinoderms, tunicates, and cephalochordates. These phyla can synthesize thyroid hormone, which has been demonstrated in some groups to induce the nuclear thyroid hormone receptor (THR). Thyroid hormone may act in these phyla through interaction with a membrane integrin receptor. Thyroid hormone regulates inter alia metamorphosis but, unlike in vertebrates, this does not occur via receptor activation by the ligands triiodothyronine (T3) and thyroxine (T4). Instead, the unliganded nuclear receptor itself controls metamorphosis in mollusks, echinoderms, and tunicates, whereas the T3 derivative tri-iodothyroacetic acid (TRIAC) acts as a THR ligand in cephalochordates. In view of this, it may be possible to develop an invertebrate-based screen that is sensitive to vertebrate THADCs that interfere with thyroid hormone synthesis or metabolism along with interaction with membrane receptors. The review makes some recommendations for the need to develop an appropriate test method. Integr Environ Assess Manag 2023;19:63-82. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
| | - Henrik Holbech
- Department of BiologyUniversity of Southern DenmarkOdense MDenmark
| | - Noémie De Crozé
- Laboratoire Recherche Environnementale, L'ORÉAL Recherche & InnovationAulnay‐sous‐BoisFrance
| | | | - Gerald A. LeBlanc
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
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Aviles A, Hulgard K, Green JW, Duus A, Holbech B, Morthorst JE. Effects of sodium perchlorate and 6-propylthiouracil on metamorphosis and thyroid gland histopathology in the European common frog (Rana temporaria). Aquat Toxicol 2022; 244:106094. [PMID: 35134604 DOI: 10.1016/j.aquatox.2022.106094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
Several chemicals have been identified as thyroid hormone axis disrupting chemicals (THADCs) able to interfere with the thyroid hormone system during fetal life and early life stages, thereby impairing neurodevelopment in mammals and inducing development and growth disorders in fish and amphibians. However, identification of THADCs is particularly challenging, and thyroid modalities are currently only assessed in vivo by mammalian and amphibian tests. The aquatic African clawed frog (Xenopus laevis/tropicalis) is the model species of the amphibian test guidelines developed by the OECD and the United States Environmental Protection Agency, but as most European amphibians are semi-aquatic, concern has been raised whether the sensitivity of native European species is comparable to Xenopus. A shortened version of the OEDC test guideline 241 (Larval Amphibian Growth and Development Assay, LAGDA) was used to investigate the effects of two model THADCs on the metamorphosis and thyroid histopathology in the European common frog (Rana temporaria). R. temporaria eggs were collected on the field and exposed till metamorphic climax to sodium perchlorate (11.9-426.5 μg/L perchlorate concentrations) and 6-propylthiouracil (PTU: 1.23-47.7 mg/L). PTU severely delayed metamorphosis and affected several thyroid gland histopathological endpoints at slightly lower concentrations compared to Xenopus. As opposed to what was described in similar Xenopus studies, we observed no effect of perchlorate on the investigated endpoints. Interspecies differences may be linked to mechanisms of action.
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Affiliation(s)
- Amandine Aviles
- Department of Biology, University of Southern Denmark, Syddansk Universitet, Odense, Denmark
| | - Katrine Hulgard
- Department of Biology, University of Southern Denmark, Syddansk Universitet, Odense, Denmark
| | - John W Green
- John W Green Ecostatistical Consulting LLC, 372 Chickory Way, Newark, DE 19711, USA
| | - Annette Duus
- Department of Biology, University of Southern Denmark, Syddansk Universitet, Odense, Denmark
| | - Bente Holbech
- Department of Biology, University of Southern Denmark, Syddansk Universitet, Odense, Denmark
| | - Jane E Morthorst
- Department of Biology, University of Southern Denmark, Syddansk Universitet, Odense, Denmark.
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Morthorst JE, Mathiesen KK, Holbech H, Pedersen KL, Bjerregaard P. Vitellogenin concentrations in feral Danish brown trout have decreased: An effect of improved sewage treatment in rural areas? Environ Toxicol Chem 2018; 37:839-845. [PMID: 29078253 DOI: 10.1002/etc.4016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/02/2017] [Accepted: 10/25/2017] [Indexed: 06/07/2023]
Abstract
Feminization of male and juvenile fish because of exposure to estrogens or estrogenic chemicals in effluents from central wastewater treatment plants (WWTPs) is a worldwide issue of concern. Intersex and induction of the female yolk protein, vitellogenin, in male and juvenile fish are robust biomarkers for estrogenic exposure, and feminized fish have been observed downstream of WWTP outlets in many countries. Danish central WWTPs reduce effluent estrogenicity effectively by advanced sewage treatment, and feminizations have not been observed downstream of central WWTP outlets. However, between 2000 and 2004, investigations of Danish streams not receiving sewage from central WWTPs revealed a high variation in vitellogenin concentrations of male juvenile brown trout (Salmo trutta); some individuals had high concentrations, probably as a result of estrogenic point sources, and the plasma concentration was >50 ng mL-1 in 79% of the juvenile males. The streams were reinvestigated in 2010 to 2016, and the average male level had decreased to a hitherto unseen baseline level; in 2010 only 0.7% (one individual) of the males had a vitellogenin concentration >50 ng mL-1 , which could indicate that the estrogenicity of the streams decreased after 2004. We examined possible estrogenic sources in streams unaffected by central WWTP effluents, and found that the reduced vitellogenin levels are most likely explained by a national effort to improve on-site wastewater treatment in scattered houses not connected to central WWTPs. Environ Toxicol Chem 2018;37:839-845. © 2017 SETAC.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | | | - Henrik Holbech
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Knud L Pedersen
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Odense, Denmark
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Morthorst JE, Lund BF, Holbech H, Bjerregaard P. Two common mild analgesics have no effect on general endocrine mediated endpoints in zebrafish (Danio rerio). Comp Biochem Physiol C Toxicol Pharmacol 2018; 204:63-70. [PMID: 29180113 DOI: 10.1016/j.cbpc.2017.11.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/22/2017] [Accepted: 11/23/2017] [Indexed: 11/28/2022]
Abstract
Mild analgesics such as acetylsalicylic acid (ASA) and acetaminophen (APAP) exert their pain-relieving effect in humans by inhibition of prostaglandin synthesis. Prostaglandins play key roles in developmental and reproductive processes in vertebrates, and in recent years, it has been suggested that weak analgesics might also act as endocrine disrupters. In a set of experiments we investigated if ASA and APAP affect well-established endocrine endpoints in zebrafish (Danio rerio), which is a commonly used model organism in the investigation of endocrine disrupting chemicals. Zebrafish were exposed to APAP (0.22, 2.3, and 30mgL-1) or ASA (0.2, 0.5, 1.7, and 8.2mgL-1) from hatch to sexual maturity in a test design resembling the OECD Fish Sexual Development Test. No effects on sex ratio and vitellogenin levels were observed. Adult zebrafish were exposed to high concentrations (mgL-1) of ASA or APAP for eight or 14days. ASA reduced the levels of prostaglandin E2, but had no effect on the concentration of 11-ketotestosterone and vitellogenin. Overall, ASA decrease prostaglandin E2 concentrations, but well-established endpoints for endocrine disruption in zebrafish are generally not affected by aquatic exposure neither during development nor adulthood. According to the WHO/IPCS definition of an endocrine disrupter, the present results do not define APAP and ASA as endocrine disrupters.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark.
| | - Birgit F Lund
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark
| | - Henrik Holbech
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark
| | - Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark
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Morthorst JE. A field study of hemolymph yolk protein levels in a bivalve (Unio tumidus) and future considerations for bivalve yolk protein as endocrine biomarker. Comp Biochem Physiol C Toxicol Pharmacol 2017; 192:16-22. [PMID: 27890716 DOI: 10.1016/j.cbpc.2016.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/16/2016] [Accepted: 11/22/2016] [Indexed: 11/18/2022]
Abstract
Induction of yolk protein in male fish is a recognized biomarker for estrogenic exposure because the estrogen-dependent induction mechanism is well investigated and there is a clear difference in yolk protein levels of unexposed males and females. Attempts have been made to use induction of bivalve yolk protein as biomarker for estrogenic exposure. However, several biomarker validation criteria have not yet been investigated e.g. an in-depth understanding of the induction mechanism and background variability is needed and reliable detection assays are yet to be developed. To obtain background knowledge about yolk protein levels freshwater bivalves (Unio tumidus) were collected in an uncontaminated Danish lake over the course of a year (33 collection dates). The hemolymph yolk protein concentration of 569 individuals was determined by a species specific enzyme-linked immunosorbent assay (ELISA) and male and female gonadal development cycles were established. The average yolk protein levels of males and females collected at each sampling date overlapped in some periods; the male and female range was 66,946 - 169,692 ng/mL and 88,731 - 681,667 ng/mL, respectively. Because male and female hemolymph yolk protein levels overlap, great care should be taken if yolk protein induction in bivalve hemolymph is considered as endocrine biomarker.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5220, Odense M, Denmark.
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Morthorst JE, Korsgaard B, Bjerregaard P. Severe malformations of eelpout (Zoarces viviparus) fry are induced by maternal estrogenic exposure during early embryogenesis. Mar Environ Res 2016; 113:80-87. [PMID: 26613261 DOI: 10.1016/j.marenvres.2015.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 11/05/2015] [Accepted: 11/09/2015] [Indexed: 06/05/2023]
Abstract
Pregnant eelpout were exposed via the water to known endocrine disrupting compounds (EDCs) to clarify if EDCs could be causing the increased eelpout fry malformation frequencies observed in coastal areas receiving high anthropogenic input. The presence of a teratogenic window for estrogen-induced malformations was also investigated by starting the exposure at different times during eelpout pregnancy. Both 17α-ethinylestradiol (EE2) (17.8 ng/L) and pyrene (0.5 μg/L) significantly increased fry malformation frequency whereas 4-t-octylphenol (4-t-OP) up to 14.3 μg/L did not. Vitellogenin was significantly induced by EE2 (5.7 and 17.8 ng/L) but not by 4-t-OP and pyrene. A critical period for estrogen-induced fry malformations was identified and closed between 14 and 22 days post fertilization (dpf). Exposure to 17β-estradiol (E2) between 0 and 14 dpf caused severe malformations and severity increased the closer exposure start was to fertilization, whereas malformations were absent by exposure starting later than 14 dpf. Data on ovarian fluid volume and larval length supported the suggested teratogenic window. Larval mortality also increased when exposure started right after fertilization.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark.
| | - Bodil Korsgaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark.
| | - Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Denmark.
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Morthorst JE, Brande-Lavridsen N, Korsgaard B, Bjerregaard P. 17β-estradiol causes abnormal development in embryos of the viviparous eelpout. Environ Sci Technol 2014; 48:14668-14676. [PMID: 25380199 DOI: 10.1021/es5046698] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Elevated frequencies of malformations among the offspring of Baltic eelpout (Zoarces viviparus) have been observed in aquatic environments receiving high anthropogenic input suggesting that manmade chemicals could be the causative agent. However, causal links between exposure to chemicals and abnormal development have never been confirmed in laboratory experiments. The purpose of this study was to investigate if exposure to 17β-estradiol (E2) causes abnormal development in larvae of the viviparous eelpout. Wild female eelpout were collected immediately after fertilization and exposed to E2 concentrations ranging from 5.7 to 133 ng L(-1) for 6 weeks in a flow through test system. The experiment shows that E2 concentrations of 53.6 and 133 ng L(-1) cause severe abnormal development among eelpout embryos. Reduced amount of ovarian fluid and increased weight of the ovarian sac indicate disturbance of ovarian function. Female plasma concentrations of E2 and vitellogenin increase in a monotonic concentration-response relationship with significant induction in the low concentration range. Our findings support the plausibility that the abnormal development among eelpout embryos encountered in monitoring programs may actually be caused by exposure to chemicals in the environment.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark , Campusvej 55, Odense M, DK-5230, Denmark
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Morthorst JE, Holbech H, Jeppesen M, Kinnberg KL, Pedersen KL, Bjerregaard P. Evaluation of yolk protein levels as estrogenic biomarker in bivalves; comparison of the alkali-labile phosphate method (ALP) and a species-specific immunoassay (ELISA). Comp Biochem Physiol C Toxicol Pharmacol 2014; 166:88-95. [PMID: 25066673 DOI: 10.1016/j.cbpc.2014.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 06/12/2014] [Accepted: 07/17/2014] [Indexed: 12/26/2022]
Abstract
Altered concentration of the vertebrate yolk protein precursor vitellogenin is a recognized biomarker for endocrine disruption in fish, and within recent years yolk protein alteration has also been associated with endocrine disruption in bivalves. Species-specific, direct and sensitive methods for quantification of vitellogenin in fish have been available for years whereas bivalve yolk protein levels have been estimated indirectly by alkali-labile phosphate (ALP) liberated from high molecular weight proteins because the sequence and biochemical structure of most bivalve yolk proteins are unknown. By applying a species-specific enzyme-linked immunosorbent assay (ELISA) for accurate determination of yolk protein level the impact of 17β-estradiol (57, 164 and 512 ng/L) on the freshwater bivalve Unio tumidus was investigated and compared with ALP estimations. Seven weeks of exposure during the pre-spawning and spawning period had no consistent effect on yolk protein concentration in hemolymph, and ALP levels in hemolymph also remained unchanged in both males and females. Further, basal male and female ALP levels were indistinguishable whereas the ELISA demonstrated that yolk protein levels of females exceeded male levels at the time of sampling, although male basal levels were high compared to fish. Altogether it is shown that individual ALP levels do not reflect yolk protein levels and hence hemolymph ALP levels cannot serve as biomarker for estrogenic exposure during the pre-spawning and spawning period in U. tumidus. The necessity of sensitive and validated biomarkers for reliable interpretation of data and the utility of ALP and yolk protein levels as biomarkers in bivalves are discussed.
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Affiliation(s)
- Jane E Morthorst
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Henrik Holbech
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Morten Jeppesen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Karin L Kinnberg
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Knud L Pedersen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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Morthorst JE, Lister A, Bjerregaard P, Van Der Kraak G. Ibuprofen reduces zebrafish PGE(2) levels but steroid hormone levels and reproductive parameters are not affected. Comp Biochem Physiol C Toxicol Pharmacol 2013; 157:251-7. [PMID: 23247296 DOI: 10.1016/j.cbpc.2012.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 02/02/2023]
Abstract
Prostaglandins are important regulators of reproductive function in fish. Analgesics like aspirin and ibuprofen are prostaglandin inhibitors and have been detected in freshwater systems at ng/L-μg/L levels. We investigated whether ibuprofen would affect prostaglandin and sex steroid hormone levels in adult zebrafish (Danio rerio) and if expression levels of genes involved in steroidogenesis and prostaglandin synthesis were affected. Zebrafish were exposed to moderate concentrations of ibuprofen (21, 201 or 506 μg/L) for 7 days in a semi-static test system. Ibuprofen concentrations were close to nominal levels and decreased by a maximum of 12-13% over 24 h. Prostaglandin E(2) (PGE(2)) levels in whole body homogenates of males and ovaries of females decreased in a monotonic dose-response relationship whereas male 11-ketotestosterone levels and ovarian 17β-estradiol levels remained unchanged. Ibuprofen did not have an influence on vitellogenin levels, female gonadosomatic index or cumulative egg production and no dose-response relationship in ovarian and testicular expression levels of the investigated genes was observed. This study shows that ibuprofen reduces PGE(2) levels in male and female zebrafish but has no consistent effects on other investigated reproductive parameters.
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Affiliation(s)
- Jane E Morthorst
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
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12
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Morthorst JE, Holbech H, Bjerregaard P. Trenbolone causes irreversible masculinization of zebrafish at environmentally relevant concentrations. Aquat Toxicol 2010; 98:336-43. [PMID: 20363039 DOI: 10.1016/j.aquatox.2010.03.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2010] [Revised: 03/05/2010] [Accepted: 03/08/2010] [Indexed: 05/16/2023]
Abstract
Feminization of fish caused by certain estrogenic compounds e.g. 17 alpha-ethinylestradiol (EE2) has been shown to be partly reversible. So far it has not been studied if this applies for androgenic compounds too. The androgenic steroid trenbolone acetate (TbA) is used as growth promoter in beef cattle in the United States, South America, and Australia. TbA metabolites are stable in animal waste and have been detected in surface waters associated with feedlot areas and studies on both fish and mammals have demonstrated a strong androgenic effect of those metabolites. Zebrafish (Danio rerio) were exposed to environmentally relevant concentrations of the TbA metabolite 17beta-trenbolone from 0 to 60 days post-hatch (dph) and either sacrificed at 60 dph, transferred to clean water for 170 days or kept in exposure for 170 days. At 60 dph gonadal histology and vitellogenin analyses revealed all-male populations in groups exposed to 15.5 and 26.2 ng/L, and at 9.2 ng/L a skewed sex ratio towards males was observed. After the depuration period no sign of reversibility was observed. Environmentally relevant concentrations of 17beta-trenbolone cause a strong and irreversible masculinization of zebrafish and that raises concern about the effects of androgenic discharges in the aquatic environment. In addition this study also aids in understanding of the so far unknown sex determination process in zebrafish.
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Affiliation(s)
- Jane E Morthorst
- Institute of Biology, University of Southern Denmark, Campusvej 55, Odense M, Denmark.
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Jørgensen A, Nielsen JE, Nielsen BF, Morthorst JE, Bjerregaard P, Leffers H. Expression of prostaglandin synthases (pgds and pges) during zebrafish gonadal differentiation. Comp Biochem Physiol A Mol Integr Physiol 2010; 157:102-8. [PMID: 20362066 DOI: 10.1016/j.cbpa.2010.03.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Revised: 03/16/2010] [Accepted: 03/22/2010] [Indexed: 10/19/2022]
Abstract
The present study aimed at elucidating whether the expression pattern of the membrane bound form of prostaglandin E2 synthase (pges) and especially the lipocalin-type prostaglandin D2 synthase (pgds) indicates involvement in gonadal sex differentiation in zebrafish as has previously been found in other species. In mice and chicken, the lipocalin-type Pgds is specifically expressed in pre-Sertoli cells just after Sry and Sox9 and is involved in masculinisation of the developing testis. Furthermore, Pges are implicated in female reproduction including follicular development and ovulation. In this study, a sexually dimorphic expression of pgds was found in gonads of adult zebrafish with expression in testis but not in ovaries. To determine whether the sex-specific expression pattern of pgds was present in gonads of juvenile zebrafish and therefore could be an early marker of sex in zebrafish, we microdissected gonads from four randomly selected individual zebrafish for every second day in the period 2-20 days post hatch (dph) and 0-1 dph. The temporal expression of pgds and pges was investigated in the microdissected gonads, however, no differential expression that could indicate sex-specific difference between individual juvenile zebrafish was observed.
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Affiliation(s)
- Anne Jørgensen
- Department of Science, Systems and Models, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark.
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Jørgensen A, Nielsen JE, Morthorst JE, Bjerregaard P, Leffers H. Laser capture microdissection of gonads from juvenile zebrafish. Reprod Biol Endocrinol 2009; 7:97. [PMID: 19747405 PMCID: PMC2755477 DOI: 10.1186/1477-7827-7-97] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 09/14/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Investigating gonadal gene expression is important in attempting to elucidate the molecular mechanism of sex determination and differentiation in the model species zebrafish. However, the small size of juvenile zebrafish and correspondingly their gonads complicates this type of investigation. Furthermore, the lack of a genetic sex marker in juvenile zebrafish prevents pooling gonads from several individuals. The aim of this study was to establish a method to isolate the gonads from individual juvenile zebrafish allowing future investigations of gonadal gene expression during sex determination and differentiation. METHODS The laser capture microdissection technique enables isolation of specific cells and tissues and thereby removes the noise of gene expression from other cells or tissues in the gene expression profile. A protocol developed for laser microdissection of human gonocytes was adjusted and optimised to isolate juvenile zebrafish gonads. RESULTS The juvenile zebrafish gonad is not morphologically distinguishable when using dehydrated cryosections on membrane slides and a specific staining method is necessary to identify the gonads. The protocol setup in this study allows staining, identification, isolation and subsequent RNA purification and amplification of gonads from individual juvenile zebrafish thereby enabling gonadal gene expression profiling. CONCLUSION The study presents a protocol for isolation of individual juvenile zebrafish gonads, which will enable future investigations of gonadal gene expression during the critical period of sex differentiation. Furthermore, the presented staining method is applicable to other species as it is directed towards alkaline phosphatase that is expressed in gonocytes and embryonic stem cells, which is conserved among vertebrate species.
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Affiliation(s)
- Anne Jørgensen
- Department of Science, Systems and Models, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - John E Nielsen
- University Department of Growth and Reproduction, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen ∅, Denmark
| | - Jane E Morthorst
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Poul Bjerregaard
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Henrik Leffers
- University Department of Growth and Reproduction, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen ∅, Denmark
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Jørgensen A, Morthorst JE, Andersen O, Rasmussen LJ, Bjerregaard P. Expression profiles for six zebrafish genes during gonadal sex differentiation. Reprod Biol Endocrinol 2008; 6:25. [PMID: 18590525 PMCID: PMC2500022 DOI: 10.1186/1477-7827-6-25] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 06/30/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The mechanism of sex determination in zebrafish is largely unknown and neither sex chromosomes nor a sex-determining gene have been identified. This indicates that sex determination in zebrafish is mediated by genetic signals from autosomal genes. The aim of this study was to determine the precise timing of expression of six genes previously suggested to be associated with sex differentiation in zebrafish. The current study investigates the expression of all six genes in the same individual fish with extensive sampling dates during sex determination and -differentiation. RESULTS In the present study, we have used quantitative real-time PCR to investigate the expression of ar, sox9a, dmrt1, fig alpha, cyp19a1a and cyp19a1b during the expected sex determination and gonadal sex differentiation period. The expression of the genes expected to be high in males (ar, sox9a and dmrt1a) and high in females (fig alpha and cyp19a1a) was segregated in two groups with more than 10 times difference in expression levels. All of the investigated genes showed peaks in expression levels during the time of sex determination and gonadal sex differentiation. Expression of all genes was investigated on cDNA from the same fish allowing comparison of the high and low expressers of genes that are expected to be highest expressed in either males or females. There were 78% high or low expressers of all three "male" genes (ar, sox9a and dmrt1) in the investigated period and 81% were high or low expressers of both "female" genes (fig alpha and cyp19a1a). When comparing all five genes with expected sex related expression 56% show expression expected for either male or female. Furthermore, the expression of all genes was investigated in different tissue of adult male and female zebrafish. CONCLUSION In zebrafish, the first significant peak in gene expression during the investigated period (2-40 dph) was dmrt1 at 10 dph which indicates involvement of this gene in the early gonadal sex differentiation of males.
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Affiliation(s)
- Anne Jørgensen
- Department of Science, Systems and Models, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Jane E Morthorst
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Ole Andersen
- Department of Science, Systems and Models, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark
| | - Lene J Rasmussen
- Department of Science, Systems and Models, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark
| | - Poul Bjerregaard
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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