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Guerrero-Limón G, Muller M. Exploring estrogen antagonism using CRISPR/Cas9 to generate specific mutants for each of the receptors. CHEMOSPHERE 2024; 364:143100. [PMID: 39159765 DOI: 10.1016/j.chemosphere.2024.143100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 07/19/2024] [Accepted: 08/13/2024] [Indexed: 08/21/2024]
Abstract
Endocrine disruptors are chemicals that have been in the spotlight for some time now. Their modulating action on endocrine signaling pathways made them a particularly interesting topic of research within the field of ecotoxicology. Traditionally, endocrine disrupting properties are studied using exposure to suspected chemicals. In recent years, a major breakthrough in biology has been the advent of targeted gene editing tools to directly assess the function of specific genes. Among these, the CRISPR/Cas9 method has accelerated progress across many disciplines in biology. This versatile tool allows to address antagonism differently, by directly inactivating the receptors targeted by endocrine disruptors. Here, we used the CRISPR/Cas9 method to knock out the different estrogen receptors in zebrafish and we assessed the potential effects this generates during development. We used a panel of biological tests generally used in zebrafish larvae to investigate exposure to compounds deemed as endocrine disrupting chemicals. We demonstrate that the absence of individual functional estrogen receptors (Esr1, Esr2b, or Gper1) does affect behavior, heart rate and overall development. Each mutant line was viable and could be grown to adulthood, the larvae tended to be morphologically grossly normal. A substantial fraction (70%) of the esr1 mutants presented severe craniofacial deformations, while the remaining 30% of esr1 mutants also had changes in behavior. esr2b mutants had significantly increased heart rate and significant impacts on craniofacial morphometrics. Finally, mutation of gper1 affected behavior, decreased standard length, and decreased bone mineralization as assessed in the opercle. Although the exact molecular mechanisms underlying these effects will require further investigations in the future, we added a new concept and new tools to explore and better understand the actions of the large group of endocrine disrupting chemicals found in our environment.
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Affiliation(s)
- Gustavo Guerrero-Limón
- Laboratory for Organogenesis and Regeneration, GIGA Institute, University of Liège, Liège, Belgium.
| | - Marc Muller
- Laboratory for Organogenesis and Regeneration, GIGA Institute, University of Liège, Liège, Belgium.
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2
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Peng W, Zhang Y, Song B, Yang P, Liu L. Developmental Delay and Male-Biased Sex Ratio in esr2b Knockout Zebrafish. Genes (Basel) 2024; 15:636. [PMID: 38790265 PMCID: PMC11121336 DOI: 10.3390/genes15050636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/27/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
The estrogen receptor signaling pathway plays an important role in vertebrate embryonic development and sexual differentiation. There are four major estrogen receptors in zebrafish: esr1, esr2a, esr2b and gper. However, the specific role of different estrogen receptors in zebrafish is not clear. To investigate the role of esr2b in zebrafish development and reproduction, this study utilized TALENs technology to generate an esr2b knockout homozygous zebrafish line. The number of eggs laid by esr2b knockout female zebrafish did not differ significantly from that of wild zebrafish. The embryonic development process of wild-type and esr2b knockout zebrafish was observed, revealing a significant developmental delay in the esr2b knockout zebrafish. Additionally, mortality rates were significantly higher in esr2b knockout zebrafish than in their wild-type counterparts at 24 hpf. The reciprocal cross experiment between esr2b knockout zebrafish and wild-type zebrafish revealed that the absence of esr2b resulted in a decline in the quality of zebrafish oocytes, while having no impact on sperm cells. The knockout of esr2b also led to an abnormal sex ratio in the adult zebrafish population, with a female-to-male ratio of approximately 1:7. The quantitative PCR (qPCR) and in situ hybridization results demonstrated a significant downregulation of cyp19ab1b expression in esr2b knockout embryos compared to wild-type embryos throughout development (at 2 dpf, 3 dpf and 4 dpf). Additionally, the estrogen-mediated induction expression of cyp19ab1b was attenuated, while the estradiol-induced upregulated expression of vtg1 was disrupted. These results suggest that esr2b is involved in regulating zebrafish oocyte development and sex differentiation.
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Affiliation(s)
- Wei Peng
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Yunsheng Zhang
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Bolan Song
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Pinhong Yang
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Liangguo Liu
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
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3
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Liu L, Miao J, Liu P, Zhao A, Yao L, Pan L. Comparison and quantification of estrogen receptor-mediated responsiveness to endocrine disruptors in bivalves by using complementary model and a novel yeast assay approach. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 323:121208. [PMID: 36738881 DOI: 10.1016/j.envpol.2023.121208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 01/20/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
Endocrine disrupting chemicals (EDCs) in estuaries and coastal habitats have been widely detected over the world and caused global concern. Bivalves have been shown to be vulnerable to endocrine disruption. However, estrogen receptors (ERs) sensitivity to steroids and EDCs has long been considered to be restricted to vertebrates. In the present study, a computational simulation docking model was applied to qualitatively predict the binding behavior of two bivalve ERs to estradiol and compared the docking activity with zebra fish ERa. A novel reconstituted yeast system was constructed by using transcriptional activator GAL-4 consists of ER-expressing plasmid and ERE (estrogen responsive element)-containing plasmid. The assays showed that bivalve ER specifically activate transcription in response to tested steroids and EDCs, but the activation ability is weaker compared to zebra fish ERa. The results corroborate the presence of an active ER in bivalve molluscs and provide a promising tool for screening of marine environmental pollutants active in disturbing ERs of bivalves, as well as understanding the underlying mechanism across taxonomic groups and phyla.
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Affiliation(s)
- Liru Liu
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Jingjing Miao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China.
| | - Peipei Liu
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Anran Zhao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Linlin Yao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Luqing Pan
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
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4
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Cohen A, Popowitz J, Delbridge-Perry M, Rowe CJ, Connaughton VP. The Role of Estrogen and Thyroid Hormones in Zebrafish Visual System Function. Front Pharmacol 2022; 13:837687. [PMID: 35295340 PMCID: PMC8918846 DOI: 10.3389/fphar.2022.837687] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/28/2022] [Indexed: 12/23/2022] Open
Abstract
Visual system development is a highly complex process involving coordination of environmental cues, cell pathways, and integration of functional circuits. Consequently, a change to any step, due to a mutation or chemical exposure, can lead to deleterious consequences. One class of chemicals known to have both overt and subtle effects on the visual system is endocrine disrupting compounds (EDCs). EDCs are environmental contaminants which alter hormonal signaling by either preventing compound synthesis or binding to postsynaptic receptors. Interestingly, recent work has identified neuronal and sensory systems, particularly vision, as targets for EDCs. In particular, estrogenic and thyroidogenic signaling have been identified as critical modulators of proper visual system development and function. Here, we summarize and review this work, from our lab and others, focusing on behavioral, physiological, and molecular data collected in zebrafish. We also discuss different exposure regimes used, including long-lasting effects of developmental exposure. Overall, zebrafish are a model of choice to examine the impact of EDCs and other compounds targeting estrogen and thyroid signaling and the consequences of exposure in visual system development and function.
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Affiliation(s)
- Annastelle Cohen
- Department of Biology, American University, Washington, DC, WA, United States
| | - Jeremy Popowitz
- Department of Biology, American University, Washington, DC, WA, United States
| | | | - Cassie J. Rowe
- Department of Biology, American University, Washington, DC, WA, United States,Center for Neuroscience and Behavior, American University, Washington, DC, WA, United States
| | - Victoria P. Connaughton
- Department of Biology, American University, Washington, DC, WA, United States,Center for Neuroscience and Behavior, American University, Washington, DC, WA, United States,*Correspondence: Victoria P. Connaughton,
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5
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Prim JH, Phillips MC, Lamm MS, Brady J, Cabral I, Durden S, Dustin E, Hazellief A, Klapheke B, Lamb AD, Lukowsky A, May D, Sanchez SG, Thompson KC, Tyler WA, Godwin J. Estrogenic signaling and sociosexual behavior in wild sex-changing bluehead wrasses, Thalassoma bifasciatum. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:24-34. [PMID: 34752686 DOI: 10.1002/jez.2558] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 12/28/2022]
Abstract
Estrogenic signaling is an important focus in studies of gonadal and brain sexual differentiation in fishes and vertebrates generally. This study examined variation in estrogenic signaling (1) across three sexual phenotypes (female, female-mimic initial phase [IP] male, and terminal phase [TP] male), (2) during socially-controlled female-to-male sex change, and (3) during tidally-driven spawning cycles in the protogynous bluehead wrasse (Thalassoma bifasciatum). We analyzed relative abundances of messenger RNAs (mRNAs) for the brain form of aromatase (cyp19a1b) and the three nuclear estrogen receptors (ER) (ERα, ERβa, and ERβb) by qPCR. Consistent with previous reports, forebrain/midbrain cyp19a1b was highest in females, significantly lower in TP males, and lowest in IP males. By contrast, ERα and ERβb mRNA abundances were highest in TP males and increased during sex change. ERβa mRNA did not vary significantly. Across the tidally-driven spawning cycle, cyp19a1b abundances were higher in females than TP males. Interestingly, cyp19a1b levels were higher in TP males close (~1 h) to the daily spawning period when sexual and aggressive behaviors rise than males far from spawning (~10-12 h). Together with earlier findings, our results suggest alterations in neural estrogen signaling are key regulators of socially-controlled sex change and sexual phenotype differences. Additionally, these patterns suggest TP male-typical sociosexual behaviors may depend on intermediate rather than low estrogenic signaling. We discuss these results and the possibility that an inverted-U shaped relationship between neural estrogen and male-typical behaviors is more common than presently appreciated.
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Affiliation(s)
- Julianna H Prim
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Marshall C Phillips
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Melissa S Lamm
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Jeannie Brady
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Itze Cabral
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Shelby Durden
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Elizabeth Dustin
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Allison Hazellief
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Brandon Klapheke
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - April D Lamb
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Alison Lukowsky
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Dianna May
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - Sidney G Sanchez
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Kelly C Thompson
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - William A Tyler
- Department of Biology, Indian River State College, Fort Pierce, Florida, USA
| | - John Godwin
- Department of Biological Sciences and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina, USA
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6
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Bernardo RC, Connaughton VP. Transient developmental exposure to tributyltin reduces optomotor responses in larval zebrafish (Danio rerio). Neurotoxicol Teratol 2022; 89:107055. [PMID: 34896240 PMCID: PMC8755603 DOI: 10.1016/j.ntt.2021.107055] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 02/06/2023]
Abstract
This study determined the effects of transient developmental exposure to tributyltin (TBT), a well-known anti-estrogenic environmental endocrine disrupting compound, on visual system development of larval zebrafish (Danio rerio). Zebrafish were exposed to either 0.2 μg/L or 20 μg/L TBT for 24 h when they were aged 24 h postfertilization (hpf), 72 hpf, or 7 days (d)pf. Immediately after exposure, larvae were transferred to system water for seven days of recovery followed by behavioral testing (startle and optomotor responses) and morphological assessment. TBT-treated larvae displayed age-dependent changes in morphology characterized by delayed/reduced growth and susceptibility to exposure. TBT exposure reduced the number of larvae displaying optomotor responses regardless of age of exposure; eye diameter was also decreased when exposure occurred at 24 hpf or 7 dpf. Startle responses were reduced only in TBT-treated larvae exposed when they were 24 hpf, suggesting transient TBT exposure during the early larval period may cause vision-specific effects.
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Affiliation(s)
- Rachel C. Bernardo
- Department of Biology, American University, Washington, DC 20016, USA.,Department of Health Studies, American University, Washington, DC 20016, USA
| | - Victoria P. Connaughton
- Department of Biology, American University, Washington, DC 20016, USA.,Corresponding author: VP Connaughton, Dept of Biology, American University, 4400 Massachusetts Ave, NW, Washington, DC 20016, 202-885-2188,
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7
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Roles of Estrogens in the Healthy and Diseased Oviparous Vertebrate Liver. Metabolites 2021; 11:metabo11080502. [PMID: 34436443 PMCID: PMC8398935 DOI: 10.3390/metabo11080502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/12/2022] Open
Abstract
The liver is a vital organ that sustains multiple functions beneficial for the whole organism. It is sexually dimorphic, presenting sex-biased gene expression with implications for the phenotypic differences between males and females. Estrogens are involved in this sex dimorphism and their actions in the liver of several reptiles, fishes, amphibians, and birds are discussed. The liver participates in reproduction by producing vitellogenins (yolk proteins) and eggshell proteins under the control of estrogens that act via two types of receptors active either mainly in the cell nucleus (ESR) or the cell membrane (GPER1). Estrogens also control hepatic lipid and lipoprotein metabolisms, with a triglyceride carrier role for VLDL from the liver to the ovaries during oogenesis. Moreover, the activation of the vitellogenin genes is used as a robust biomarker for exposure to xenoestrogens. In the context of liver diseases, high plasma estrogen levels are observed in fatty liver hemorrhagic syndrome (FLHS) in chicken implicating estrogens in the disease progression. Fishes are also used to investigate liver diseases, including models generated by mutation and transgenesis. In conclusion, studies on the roles of estrogens in the non-mammalian oviparous vertebrate liver have contributed enormously to unveil hormone-dependent physiological and physiopathological processes.
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8
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Hering I, Eilebrecht E, Parnham MJ, Weiler M, Günday-Türeli N, Türeli AE, Modh H, Heng PWS, Böhmer W, Schäfers C, Fenske M, Wacker MG. Microparticle formulations alter the toxicity of fenofibrate to the zebrafish Danio rerio embryo. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2021; 234:105798. [PMID: 33799113 DOI: 10.1016/j.aquatox.2021.105798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 02/27/2021] [Accepted: 03/03/2021] [Indexed: 06/12/2023]
Abstract
A wide variety of active pharmaceutical ingredients are released into the environment and pose a threat to aquatic organisms. Drug products using micro- and nanoparticle technology can lower these emissions into the environment by their increased bioavailability to the human patients. However, due to this enhanced efficacy, micro- and nanoscale drug delivery systems can potentially display an even higher toxicity, and thus also pose a risk to non-target organisms. Fenofibrate is a lipid-regulating agent and exhibits species-related hazards in fish. The ecotoxic effects of a fenofibrate formulation embedded into a hydroxypropyl methylcellulose microparticle matrix, as well as those of the excipients used in the formulation process, were evaluated. To compare the effects of fenofibrate without a formulation, fenofibrate was dispersed in diluted ISO water alone or dissolved in the solvent DMF and then added to diluted ISO water. The effects of these various treatments were assessed using the fish embryo toxicity test, acridine orange staining and gene expression analysis assessed by quantitative RT polymerase chain reaction. Exposure concentrations were assessed by chemical analysis. The effect threshold concentrations of fenofibrate microparticle precipitates were higher compared to the formulation. Fenofibrate dispersed in 20%-ISO-water displayed the lowest toxicity. For the fenofibrate formulation as well as for fenofibrate added as a DMF solution, greater ecotoxic effects were observed in the zebrafish embryos. The chemical analysis of the solutions revealed that more fenofibrate was present in the samples with the fenofibrate formulation as well as fenofibrate added as a DMF solution compared to fenofibrate dispersed in diluted ISO water. This could explain the higher ecotoxicity. The toxic effects on the zebrafish embryo thus suggested that the formulation as well as the solvent increased the bioavailability of fenofibrate.
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Affiliation(s)
- Indra Hering
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Theodor-Stern-Kai 7, 60596, Frankfurt/Main, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392, Schmallenberg, Germany; Goethe University Frankfurt am Main, Department Aquatic Ecotoxicology, Max-von-Laue-Str. 13, 60438, Frankfurt am Main, Germany.
| | - Elke Eilebrecht
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392, Schmallenberg, Germany
| | - Michael J Parnham
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Theodor-Stern-Kai 7, 60596, Frankfurt/Main, Germany
| | - Marc Weiler
- MyBiotech GmbH, Industriestraße 1B, 66802, Überherrn, Germany
| | | | | | - Harshvardhan Modh
- National University of Singapore, Department of Pharmacy, Faculty of Science, Wet Science Building (S9), 5 Science Drive 2, 117546, Singapore, Singapore
| | - Paul W S Heng
- National University of Singapore, GEA-NUS Pharmaceutical Processing Research Laboratory, Department of Pharmacy, Faculty of Science, 18 Science Drive 4, 117543, Singapore, Singapore
| | - Walter Böhmer
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392, Schmallenberg, Germany
| | - Christoph Schäfers
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392, Schmallenberg, Germany
| | - Martina Fenske
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Theodor-Stern-Kai 7, 60596, Frankfurt/Main, Germany.
| | - Matthias G Wacker
- National University of Singapore, Department of Pharmacy, Faculty of Science, Wet Science Building (S9), 5 Science Drive 2, 117546, Singapore, Singapore
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9
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Crowley-Perry M, Barberio AJ, Zeino J, Winston ER, Connaughton VP. Zebrafish Optomotor Response and Morphology Are Altered by Transient, Developmental Exposure to Bisphenol-A. J Dev Biol 2021; 9:jdb9020014. [PMID: 33918232 PMCID: PMC8167563 DOI: 10.3390/jdb9020014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/22/2021] [Accepted: 03/25/2021] [Indexed: 12/15/2022] Open
Abstract
Estrogen-specific endocrine disrupting compounds (EDCs) are potent modulators of neural and visual development and common environmental contaminants. Using zebrafish, we examined the long-term impact of abnormal estrogenic signaling by testing the effects of acute, early exposure to bisphenol-A (BPA), a weak estrogen agonist, on later visually guided behaviors. Zebrafish aged 24 h postfertilization (hpf), 72 hpf, and 7 days postfertilization (dpf) were exposed to 0.001 μM or 0.1 μM BPA for 24 h, and then allowed to recover for 1 or 2 weeks. Morphology and optomotor responses (OMRs) were assessed after 1 and 2 weeks of recovery for 24 hpf and 72 hpf exposure groups; 7 dpf exposure groups were additionally assessed immediately after exposure. Increased notochord length was seen in 0.001 μM exposed larvae and decreased in 0.1 μM exposed larvae across all age groups. Positive OMR was significantly increased at 1 and 2 weeks post-exposure in larvae exposed to 0.1 μM BPA when they were 72 hpf or 7 dpf, while positive OMR was increased after 2 weeks of recovery in larvae exposed to 0.001 μM BPA at 72 hpf. A time-delayed increase in eye diameter occurred in both BPA treatment groups at 72 hpf exposure; while a transient increase occurred in 7 dpf larvae exposed to 0.1 μM BPA. Overall, short-term developmental exposure to environmentally relevant BPA levels caused concentration- and age-dependent effects on zebrafish visual anatomy and function.
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Affiliation(s)
- Mikayla Crowley-Perry
- Department of Biology, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA; (M.C.-P.); (A.J.B.); (J.Z.); (E.R.W.)
- Department of Chemistry, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA
| | - Angelo J. Barberio
- Department of Biology, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA; (M.C.-P.); (A.J.B.); (J.Z.); (E.R.W.)
| | - Jude Zeino
- Department of Biology, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA; (M.C.-P.); (A.J.B.); (J.Z.); (E.R.W.)
| | - Erica R. Winston
- Department of Biology, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA; (M.C.-P.); (A.J.B.); (J.Z.); (E.R.W.)
| | - Victoria P. Connaughton
- Department of Biology, American University, 4400 Massachusetts Ave NW, Washington, DC 20016, USA; (M.C.-P.); (A.J.B.); (J.Z.); (E.R.W.)
- Correspondence: ; Tel.: +1-202-885-2188
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10
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Moraes AB, Giacomini ACVV, Genario R, Marcon L, Scolari N, Bueno BW, Demin KA, Amstislavskaya TG, Strekalova T, Soares MC, de Abreu MS, Kalueff AV. Pro-social and anxiolytic-like behavior following a single 24-h exposure to 17β-estradiol in adult male zebrafish. Neurosci Lett 2020; 747:135591. [PMID: 33359732 DOI: 10.1016/j.neulet.2020.135591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/30/2020] [Accepted: 12/18/2020] [Indexed: 01/06/2023]
Abstract
Estradiol (17β-estradiol, E2) is a crucial estrogen hormone that regulates sexual, cognitive, social and affective behaviors in various species. However, complex central nervous system (CNS) effects of E2, including its activity in males, remain poorly understood. The zebrafish (Danio rerio) is rapidly becoming a powerful novel model system in translational neuroscience research. Here, we evaluate the effects of a single 24-h exposure to 20 μg/L of E2 on behavioral and endocrine (cortisol) responses in adult male zebrafish. Overall, E2 exerted pro-social effect in the social preference test, reduced whole-body cortisol levels, elevated exploration in the novel tank test and increased the shoal size in the shoaling test, indicative of an anxiolytic-like profile of this hormone in male zebrafish. Supporting mounting human and rodent evidence on the role of E2 in behavioral regulation, the observed pro-social and anxiolytic-like effects of E2 in male zebrafish reinforce the use of this aquatic organism in studying steroid-mediated CNS mechanisms of complex affective and social behaviors.
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Affiliation(s)
- Andréia B Moraes
- Postgraduate Program in Environmental Sciences, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Ana C V V Giacomini
- Postgraduate Program in Environmental Sciences, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil; Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Rafael Genario
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Leticia Marcon
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Naiara Scolari
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Barbara W Bueno
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Konstantin A Demin
- Institute of Experimental Medicine, Almazov National Medcial Research Center, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia; Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia; Granov Russian Scientific Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia; Neuroscience Program, Sirius University, Sochi, Russia
| | - Tamara G Amstislavskaya
- Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia; Zelman Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
| | - Tatyana Strekalova
- Department of Psychiatry and Neuropsychology, Maastricht University, Netherlands; Laboratory of Psychiatric Neurobiology, Sechenov 1st Moscow State Medical University, Moscow, Russia; Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Marta C Soares
- CIBIO, Research Centre in Biodiversity and Genetic Resources, University of Porto, Vairão, Portugal
| | - Murilo S de Abreu
- The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA; Laboratory of Cell and Molecular Biology and Neurobiology, Moscow Institute of Physics and Technology, Moscow, Russia; Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil.
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Chongqing, China; Ural Federal University, Ekaterinburg, Russia.
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11
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Mushirobira Y, Niida M, Hotta T, Fujinami Y, Soyano K. Hepatic expression profiles of three subtypes of vitellogenin and estrogen receptor during vitellogenesis in cultured female yellowtail. Gen Comp Endocrinol 2020; 299:113612. [PMID: 32950579 DOI: 10.1016/j.ygcen.2020.113612] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 12/23/2022]
Abstract
Estradiol-17β (E2) promotes the transcription of vitellogenin (Vtg) via nuclear estrogen receptor (ER). Three Vtg (VtgAa, VtgAb, and VtgC) and ER subtypes (ERα, ERβ1, and ERβ2) have been reported in perciform fish; however, the relationship between the transcriptional regulation of Vtg and ER subtypes remains unclear. Molecular characterization was performed and the expression profiles of vtg and er subtypes were investigated to elucidate mechanisms of synthesis of vtg subtypes in yellowtail, Seriola quinqueradiata. Primary structures and promoter regions were revealed in three subtypes of vtg and er, and all the vtg subtypes and erα were presumed to be estrogen-responsive genes. When all vtg subtypes were expressed significantly in the liver, hepatic expression levels of all the er subtypes also increased. Conversely, although plasma E2 concentrations did not change significantly, the concentrations were high at the same time. Hepatic expression levels of all the vtg subtypes were highly correlated with hepatic erα, rather than with hepatic erβ subtypes and plasma E2. A high positive correlation was also observed between erβ1 and β2, which seemed to be highly expressed at the pre- and late-vitellogenic stages. The results of the present study suggest that the transcription of the three vtg subtypes are regulated by three ER subtypes jointly, and ERα is the key transcription factor regulating the three vtg subtypes in yellowtail.
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Affiliation(s)
- Yuji Mushirobira
- Institute for East China Sea Research, Organization for Marine Science and Technology, Nagasaki University, 1551-7, Taira-machi, Nagasaki 851-2213, Nagasaki, Japan
| | - Mitsuru Niida
- Institute for East China Sea Research, Organization for Marine Science and Technology, Nagasaki University, 1551-7, Taira-machi, Nagasaki 851-2213, Nagasaki, Japan; Graduate School of Fisheries and Environmental Sciences, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Nagasaki, Japan
| | - Takurou Hotta
- Goto Station, Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, 122-7 Nunoura, Goto 853-0508, Nagasaki, Japan
| | - Yuichiro Fujinami
- Goto Station, Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, 122-7 Nunoura, Goto 853-0508, Nagasaki, Japan
| | - Kiyoshi Soyano
- Institute for East China Sea Research, Organization for Marine Science and Technology, Nagasaki University, 1551-7, Taira-machi, Nagasaki 851-2213, Nagasaki, Japan.
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12
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Yan L, Feng H, Wang F, Lu B, Liu X, Sun L, Wang D. Establishment of three estrogen receptors (esr1, esr2a, esr2b) knockout lines for functional study in Nile tilapia. J Steroid Biochem Mol Biol 2019; 191:105379. [PMID: 31078694 DOI: 10.1016/j.jsbmb.2019.105379] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/06/2019] [Accepted: 05/08/2019] [Indexed: 12/25/2022]
Abstract
Estrogens play fundamental roles in regulating reproductive activities and they act through estrogen receptors (ESRs) in all vertebrates. To date, distinct roles of estrogen receptors have been characterized only in human and model organisms, including mouse, rat, zebrafish and medaka. Physiological role of estrogen/receptor signaling in reproduction remains poorly defined in non-model organisms. In the present study, we successfully generated esr1, esr2a and esr2b mutant lines in tilapia by CRISPR/Cas9 and examined their phenotypes. Surprisingly, the esr1 mutants showed no phenotypes of reproductive development and function in both females and males. The esr2a mutant females showed significantly delayed ovarian development and follicle growth at 90 and 180 dah, and the development caught up later at 360 dah. The esr2a mutant males showed no phenotypes at 90 dah, and displayed smaller gonads and efferent ducts, less spermatogonia and more abnormal sperms at 180 dah. In contrast, the esr2b mutants displayed abnormal development of ovarian ducts and efferent ducts which failed to connect to the genital orifice, and which in turn, resulted in infertility in female and male, respectively, although they produced gametes in their gonads. Taken together, our study provides evidence for differential functions of esr1, esr2a and esr2b in fish reproduction.
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Affiliation(s)
- Longxia Yan
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Haiwei Feng
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Feilong Wang
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Baoyue Lu
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Xingyong Liu
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Lina Sun
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China.
| | - Deshou Wang
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China.
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13
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Thitiphuree T, Nagasawa K, Osada M. Molecular identification of steroidogenesis-related genes in scallops and their potential roles in gametogenesis. J Steroid Biochem Mol Biol 2019; 186:22-33. [PMID: 30195968 DOI: 10.1016/j.jsbmb.2018.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 09/04/2018] [Accepted: 09/04/2018] [Indexed: 01/09/2023]
Abstract
Sex steroids are crucial for controlling gametogenesis and germ cell maturation in vertebrates. It has been proposed that Yesso scallop (Mizuhopecten yessoensis) has the same sex steroids as those animals, but the scallop biosynthetic pathway is unclear. In this study, we characterized several steroidogenesis-related genes in M. yessoensis and proposed a putative biosynthetic pathway for sex steroids that is similar to that of vertebrates. Specifically, we identified several steroidogenesis-related gene sequences that encode steroid metabolizing enzymes: StAR-related lipid transfer (START) protein, 17α-hydroxylase, 17,20-lyase (cyp17a), 17β-hydroxysteroid dehydrogenase (hsd17b), and 3β-hydroxysteroid dehydrogenase (hsd3b). We sampled adult scallops throughout their reproductive phase to compare their degree of maturation with their intensity of mRNA expression. Semi-quantitative RT-PCR analysis revealed a ubiquitous expression of transcripts for steroid metabolizing enzymes (i.e., star, cyp17a, hsd17b, and hsd3b) in peripheral and gonadal tissues. Real-time PCR analysis revealed a high level of expression of star3 and cyp17a genes in gonadal tissues at the early stage of cell differentiation in scallops. Interestingly, mRNA expression of hsd3b and hsd17b genes showed a synchronous pattern related to degree of gonad maturity. These results indicate that both hsd3b and hsd17b genes are likely involved in steroidogenesis in scallops. We therefore believe that these steroid-metabolizing enzymes allow scallops to endogenously produce sex steroids to regulate reproductive events.
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Affiliation(s)
- Tongchai Thitiphuree
- Laboratory of Aquacultural Biology, Graduate School of Agricultural Science, Tohoku University, 468-1Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Kazue Nagasawa
- Laboratory of Aquacultural Biology, Graduate School of Agricultural Science, Tohoku University, 468-1Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Makoto Osada
- Laboratory of Aquacultural Biology, Graduate School of Agricultural Science, Tohoku University, 468-1Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan.
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14
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Crowder CM, Romano SN, Gorelick DA. G Protein-Coupled Estrogen Receptor Is Not Required for Sex Determination or Ovary Function in Zebrafish. Endocrinology 2018; 159:3515-3523. [PMID: 30169775 PMCID: PMC6137278 DOI: 10.1210/en.2018-00685] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 08/17/2018] [Indexed: 01/22/2023]
Abstract
Estrogens regulate vertebrate development and function through binding to nuclear estrogen receptors α and β (ERα and ERβ) and the G protein-coupled estrogen receptor (GPER). Studies in mutant animal models demonstrated that ERα and ERβ are required for normal ovary development and function. However, the degree to which GPER signaling contributes to ovary development and function is less well understood. Previous studies using cultured fish oocytes found that estradiol inhibits oocyte maturation in a GPER-dependent manner, but whether GPER regulates oocyte maturation in vivo is not known. To test the hypothesis that GPER regulates oocyte maturation in vivo, we assayed ovary development and function in gper mutant zebrafish. We found that homozygous mutant gper embryos developed into male and female adults with normal sex ratios. Adult mutant fish exhibited normal secondary sex characteristics and fertility. Additionally, mutant ovaries were histologically normal. We observed no differences in the number of immature versus mature oocytes in mutant versus wild-type ovaries from both young and aged adults. Furthermore, expression of genes associated with sex determination and ovary function was normal in gper mutant ovaries compared with wild type. Our findings suggest that GPER is not required for sex determination, ovary development, or fertility in zebrafish.
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Affiliation(s)
- Camerron M Crowder
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Shannon N Romano
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Daniel A Gorelick
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Molecular and Cellular Biology, Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas
- Correspondence: Daniel A. Gorelick, PhD, Department of Molecular and Cellular Biology, Center for Precision Environmental Health, Baylor College of Medicine, Alkek Building, Suite N1317.02, One Baylor Plaza, BCM229, Houston, Texas 77030. E-mail:
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15
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Sarasquete C, Úbeda-Manzanaro M, Ortiz-Delgado JB. Toxicity and non-harmful effects of the soya isoflavones, genistein and daidzein, in embryos of the zebrafish, Danio rerio. Comp Biochem Physiol C Toxicol Pharmacol 2018; 211:57-67. [PMID: 29870789 DOI: 10.1016/j.cbpc.2018.05.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/28/2018] [Accepted: 05/30/2018] [Indexed: 02/05/2023]
Abstract
Based on the assumed oestrogenic and apoptotic properties of soya isoflavones (genistein, daidzein), and following the current OECD test-guidelines and principle of 3Rs, we have studied the potential toxicity of phytochemicals on the zebrafish embryos test (ZFET). For this purpose, zebrafish embryos at 2-3 h post-fertilisation (hpf) were exposed to both soya isoflavones (from 1.25 mg/L to 20 mg/L) and assayed until 96 hpf. Lethal and sub-lethal endpoints (mortality, hatching rates and malformations) were estimated in the ZFET, which was expanded to potential gene expression markers, determining the lowest observed effect (and transcriptional) concentrations (LOEC, LOTEC), and the no-observable effect (and transcriptional) concentrations (NOEC, NOTEC). The results revealed that genistein is more toxic (LC50-96 hpf: 4.41 mg/L) than daidzein (over 65.15 mg/L). Both isoflavones up-regulated the oestrogen (esrrb) and death receptors (fas) and cyp1a transcript levels. Most thyroid transcript signals were up-regulated by genistein (except for thyroid peroxidase/tpo), and the hatching enzyme (he1a1) was exclusively up-regulated by daidzein (from 1.25 mg/L onwards). The ZFET proved suitable for assessing toxicant effects of both isoflavones and potential disruptions (i.e. oestrogenic, apoptotic, thyroid, enzymatic) during the embryogenesis and the endotrophic larval period.
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Affiliation(s)
- Carmen Sarasquete
- Instituto de Ciencias Marinas de Andalucía-ICMAN-CSIC, Spain; Campus Universitario Rio San Pedro, Apdo oficial, 11510, Puerto Real, Cádiz, Spain.
| | - María Úbeda-Manzanaro
- Instituto de Ciencias Marinas de Andalucía-ICMAN-CSIC, Spain; Campus Universitario Rio San Pedro, Apdo oficial, 11510, Puerto Real, Cádiz, Spain
| | - Juan B Ortiz-Delgado
- Instituto de Ciencias Marinas de Andalucía-ICMAN-CSIC, Spain; Campus Universitario Rio San Pedro, Apdo oficial, 11510, Puerto Real, Cádiz, Spain
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16
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Hou ZS, Wen HS, Li JF, He F, Li Y, Tao YX. Expression of estrogen receptors in female rainbow trout (Oncorhynchus mykiss) during first ovarian development and under dense rearing condition. Gen Comp Endocrinol 2018; 259:1-11. [PMID: 29017850 DOI: 10.1016/j.ygcen.2017.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 09/07/2017] [Accepted: 10/06/2017] [Indexed: 10/18/2022]
Abstract
To study the expression of four estrogen receptor genes (erα1, erα2, erβ1, erβ2) of female rainbow trout (Oncorhynchus mykiss) during first ovarian development, trouts were sampled from different ovarian stages. Serum E2 (estradiol) was measured by ELISA and estrogen receptors mRNA expression were examined by qRT-PCR. Our results showed a close association between increased erα1 and vitellogenin mRNA expression during ovarian maturation and increased erα2 mRNA expression in mature ovarian stages. Correlation analysis revealed that a negative relationship between serum E2 and ovarian erβ1 (or hepatic erβ2), but ovarian erβ2 mRNA expression was relatively unchanged during first ovarian development. Trout were also reared in different densities as stocking density 1, 2 and 3 (SD1, 4.6-31.1 kg/m3; SD2, 6.6-40.6 kg/m3; SD3, 8.6-49.3 kg/m3) to elucidate effects of high density on estrogen receptor expression. Histology observation showed ovarian development of trout in higher densities were retard with a relatively early stage and fewer vitellogenin accumulation. Trout in high densities showed significantly decreased serum E2, erα mRNA expression and increasing trends of erβ mRNA expression. A noticeable increase of ovarian erβ2 mRNA expression was seen in trout when density is approaching to 50 kg/m3. In conclusion, we may hypothesize that increased erβ mRNA expression triggered by high density result in decreased erα mRNA expression and vitellogenesis. As a result, ovarian development in higher densities was retard.
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Affiliation(s)
- Zhi-Shuai Hou
- Fisheries College, Ocean University of China, Qingdao 266003, China; Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, United States
| | - Hai-Shen Wen
- Fisheries College, Ocean University of China, Qingdao 266003, China.
| | - Ji-Fang Li
- Fisheries College, Ocean University of China, Qingdao 266003, China
| | - Feng He
- Fisheries College, Ocean University of China, Qingdao 266003, China
| | - Yun Li
- Fisheries College, Ocean University of China, Qingdao 266003, China
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, United States
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17
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Diotel N, Charlier TD, Lefebvre d'Hellencourt C, Couret D, Trudeau VL, Nicolau JC, Meilhac O, Kah O, Pellegrini E. Steroid Transport, Local Synthesis, and Signaling within the Brain: Roles in Neurogenesis, Neuroprotection, and Sexual Behaviors. Front Neurosci 2018; 12:84. [PMID: 29515356 PMCID: PMC5826223 DOI: 10.3389/fnins.2018.00084] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/02/2018] [Indexed: 01/18/2023] Open
Abstract
Sex steroid hormones are synthesized from cholesterol and exert pleiotropic effects notably in the central nervous system. Pioneering studies from Baulieu and colleagues have suggested that steroids are also locally-synthesized in the brain. Such steroids, called neurosteroids, can rapidly modulate neuronal excitability and functions, brain plasticity, and behavior. Accumulating data obtained on a wide variety of species demonstrate that neurosteroidogenesis is an evolutionary conserved feature across fish, birds, and mammals. In this review, we will first document neurosteroidogenesis and steroid signaling for estrogens, progestagens, and androgens in the brain of teleost fish, birds, and mammals. We will next consider the effects of sex steroids in homeostatic and regenerative neurogenesis, in neuroprotection, and in sexual behaviors. In a last part, we will discuss the transport of steroids and lipoproteins from the periphery within the brain (and vice-versa) and document their effects on the blood-brain barrier (BBB) permeability and on neuroprotection. We will emphasize the potential interaction between lipoproteins and sex steroids, addressing the beneficial effects of steroids and lipoproteins, particularly HDL-cholesterol, against the breakdown of the BBB reported to occur during brain ischemic stroke. We will consequently highlight the potential anti-inflammatory, anti-oxidant, and neuroprotective properties of sex steroid and lipoproteins, these latest improving cholesterol and steroid ester transport within the brain after insults.
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Affiliation(s)
- Nicolas Diotel
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
| | - Thierry D. Charlier
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Christian Lefebvre d'Hellencourt
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
| | - David Couret
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
- CHU de La Réunion, Saint-Denis, France
| | | | - Joel C. Nicolau
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Olivier Meilhac
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
- CHU de La Réunion, Saint-Denis, France
| | - Olivier Kah
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Elisabeth Pellegrini
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
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18
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J. M. Schaaf M. The First Fifteen Years of Steroid Receptor Research in Zebrafish; Characterization and Functional Analysis of the Receptors. NUCLEAR RECEPTOR RESEARCH 2017. [DOI: 10.11131/2017/101286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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19
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Lu H, Cui Y, Jiang L, Ge W. Functional Analysis of Nuclear Estrogen Receptors in Zebrafish Reproduction by Genome Editing Approach. Endocrinology 2017; 158:2292-2308. [PMID: 28398516 DOI: 10.1210/en.2017-00215] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/03/2017] [Indexed: 01/09/2023]
Abstract
Estrogens signal through both nuclear and membrane receptors with most reported effects being mediated via the nuclear estrogen receptors (nERs). Although much work has been reported on nERs in the zebrafish, there is a lack of direct genetic evidence for their functional roles and importance in reproduction. To address this issue, we undertook this study to disrupt all three nERs in the zebrafish, namely esr1 (ERα), esr2a (ERβII), and esr2b (ERβI), by the genome-editing technology clustered regularly interspaced short palindromic repeats and its associated nuclease (CRISPR/Cas9). Using this loss-of-function genetic approach, we successfully created three mutant zebrafish lines with each nER knocked out. In addition, we also generated all possible double and triple knockouts of the three nERs. The phenotypes of these mutants in reproduction were analyzed in all single, double, and triple nER knockouts in both females and males. Surprisingly, all three single nER mutant fish lines display normal reproductive development and function in both females and males, suggesting functional redundancy among these nERs. Further analysis of double and triple knockouts showed that nERs, especially Esr2a and Esr2b, were essential for female reproduction, and loss of these two nERs led to an arrest of folliculogenesis at previtellogenic stage II followed by sex reversal from female to male. In addition, the current study also revealed a unique role for Esr2a in follicle cell proliferation and transdifferentiation, follicle growth, and chorion formation. Taken together, this study provides the most comprehensive genetic analysis for differential functions of esr1, esr2a, and esr2b in fish reproduction.
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Affiliation(s)
- Huijie Lu
- Centre of Reproduction, Development, and Aging (CRDA), Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Yong Cui
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Wei Ge
- Centre of Reproduction, Development, and Aging (CRDA), Faculty of Health Sciences, University of Macau, Taipa, Macau, China
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20
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Nikoleris L, Hultin CL, Hallgren P, Hansson MC. 17α-Ethinylestradiol (EE2) treatment of wild roach (Rutilus rutilus) during early life development disrupts expression of genes directly involved in the feedback cycle of estrogen. Comp Biochem Physiol C Toxicol Pharmacol 2016; 180:56-64. [PMID: 26689641 DOI: 10.1016/j.cbpc.2015.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 10/01/2015] [Accepted: 12/07/2015] [Indexed: 12/11/2022]
Abstract
Fish are more sensitive to introduced disturbances from synthetic endocrine disrupting compounds during early life phases compared with mature stages. 17α-Ethinylestradiol (EE2), which is the active compound in human oral contraceptives and hormone replacement therapies, is today ever present in the effluents from sewage treatment plants. EE2 targets and interacts with the endogenous biological systems of exposed vertebrates resulting in to large extents unknown short- and long-term effects. We investigated how EE2 exposure affects expression profiles of a large number of target genes during early life of roach (Rutilus rutilus). We exposed fertilized roach eggs collected from a lake in Southern Sweden to EE2 for 12weeks together with 1+-year-old roach in aquaria. We measured the gene expression of the estrogen receptor (esr)1/2a/2b, androgen receptor (ar), vitellogenin, cytochrome P450 (cyp)19a1a/1b in fertilized eggs; newly hatched larvae; 12-week-old fry; and juvenile wild roach (1+-year-old). Results shows that an EE2 concentration as low as 0.5ng/L significantly affects gene expression during early development. Gene expression responses vary both among life stages and molecular receptors. We also show that the gene profile of the estrogen feedback cycle to a large extent depends on the relationship between the three esr genes and the two cyp19a1 genes, which are all up-regulated with age. Results indicate that a disruption of the natural activity of the dominant esr gene could lead to detrimental biological effects if EE2 exposure occurs during development, even if this exposure occurred for only a short period.
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Affiliation(s)
- Lina Nikoleris
- Centre for Environmental and Climate Research (CEC), Lund University, SE-223 62 Lund, Sweden; Section for Biodiversity, Department of Biology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
| | - Cecilia L Hultin
- Centre for Environmental and Climate Research (CEC), Lund University, SE-223 62 Lund, Sweden
| | - Per Hallgren
- Section for Aquatic Ecology, Department of Biology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
| | - Maria C Hansson
- Centre for Environmental and Climate Research (CEC), Lund University, SE-223 62 Lund, Sweden.
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21
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Tokarz J, Möller G, Hrabě de Angelis M, Adamski J. Steroids in teleost fishes: A functional point of view. Steroids 2015; 103:123-44. [PMID: 26102270 DOI: 10.1016/j.steroids.2015.06.011] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/11/2015] [Accepted: 06/15/2015] [Indexed: 01/23/2023]
Abstract
Steroid hormones are involved in the regulation of a variety of processes like embryonic development, sex differentiation, metabolism, immune responses, circadian rhythms, stress response, and reproduction in vertebrates. Teleost fishes and humans show a remarkable conservation in many developmental and physiological aspects, including the endocrine system in general and the steroid hormone related processes in particular. This review provides an overview of the current knowledge about steroid hormone biosynthesis and the steroid hormone receptors in teleost fishes and compares the findings to the human system. The impact of the duplicated genome in teleost fishes on steroid hormone biosynthesis and perception is addressed. Additionally, important processes in fish physiology regulated by steroid hormones, which are most dissimilar to humans, are described. We also give a short overview on the influence of anthropogenic endocrine disrupting compounds on steroid hormone signaling and the resulting adverse physiological effects for teleost fishes. By this approach, we show that the steroidogenesis, hormone receptors, and function of the steroid hormones are reasonably well understood when summarizing the available data of all teleost species analyzed to date. However, on the level of a single species or a certain fish-specific aspect of physiology, further research is needed.
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Affiliation(s)
- Janina Tokarz
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Experimental Genetics, Genome Analysis Center, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Gabriele Möller
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Experimental Genetics, Genome Analysis Center, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Experimental Genetics, Genome Analysis Center, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany; Lehrstuhl für Experimentelle Genetik, Technische Universität München, 85350 Freising-Weihenstephan, Germany; Member of German Center for Diabetes Research (DZD), Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Jerzy Adamski
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Experimental Genetics, Genome Analysis Center, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany; Lehrstuhl für Experimentelle Genetik, Technische Universität München, 85350 Freising-Weihenstephan, Germany; Member of German Center for Diabetes Research (DZD), Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany.
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Sun L, Zuo Z, Chen M, Chen Y, Wang C. Reproductive and transgenerational toxicities of phenanthrene on female marine medaka (Oryzias melastigma). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 162:109-116. [PMID: 25805703 DOI: 10.1016/j.aquatox.2015.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 03/15/2015] [Accepted: 03/18/2015] [Indexed: 05/26/2023]
Abstract
Phenanthrene (PHE) is one of the most abundant polycyclic aromatic hydrocarbons in the aquatic environment and often results from oil spills. To assess the effects of PHE on fish, marine medaka (Oryzias melastigma) was exposed to PHE at 0.06, 0.6, 6 and 60 μg/L. The reproductive functions and transgenerational effects were investigated. After 80 days exposure, the percentage of previtellogenic and vitellogenic oocytes in the ovary showed a significant decrease in the 0.06 and 60 μg/L groups. The mRNA levels of salmon-type gonadotropin releasing hormone, the follicle-stimulating hormone FSHβ, and the luteinizing hormone LHβ in the brain; the cytochrome P450 aromatase gene CYP19A and the estrogen receptor α (ERα) in the ovary; and ERα and vitellogenin VTG1 and 2 in the liver all exhibited significant down-regulation in the 0.06 and 60 μg/L groups, but did not significantly change in the 6 μg/L group compared to the control, which was quite consistent with development of the oocytes. A significant elevation of PHE accumulation in the brain in the 0.06 and 60 μg/L groups gave a reasonable explanation for the nonmonotonic dose-response and also elucidated the action pathway via the brain-pituitary-gonadal axis. The reduction of the time to hatch and the increased cardiac rhythm of embryos were in accord with the PHE accumulative levels in the eggs. The results demonstrated that exposure to PHE at both low and high concentrations can inhibit ovary development. In addition, PHE can be maternally transferred to embryos and influence the health and sustainability of the next generation.
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Affiliation(s)
- Lingbin Sun
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Zhenghong Zuo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Meng Chen
- Key Laboratory of Ministry of Education for Subtropical Wetland Ecosystem Research, Xiamen University, Xiamen, PR China
| | - Yixin Chen
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Chonggang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, PR China.
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23
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Transcripts involved in steroid biosynthesis and steroid receptor signaling are expressed early in development in the fathead minnow (Pimephales promelas). Comp Biochem Physiol B Biochem Mol Biol 2015; 182:64-72. [DOI: 10.1016/j.cbpb.2014.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/15/2014] [Accepted: 12/16/2014] [Indexed: 01/02/2023]
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24
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Zhao J, Zhu X, Xu T, Yin D. Structure-dependent activities of polybrominated diphenyl ethers and hydroxylated metabolites on zebrafish retinoic acid receptor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:1723-1730. [PMID: 25077655 DOI: 10.1007/s11356-014-3364-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 07/21/2014] [Indexed: 06/03/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs), a group of potential endocrine-disrupting chemicals (EDCs) have been shown to disrupt retinoid homeostasis in different species in both laboratory and field studies. However, the molecular mechanisms of interactions with the retinoic acid receptor (RAR) are not fully understood. Zebrafish have proven useful for investigating mechanisms of chemical toxicity. In the present study, a reporter gene assay was used to investigate the activities of 11 PBDEs and six OH-PBDEs with different degrees of bromination on zebrafish RAR. All tested OH-PBDEs induced RAR transcriptional activity; however, of the 11 PBDEs examined, only BDE28 and BDE154 affected the RAR transcriptional activity. Homology modeling and molecular docking were employed to simulate the interactions of PBDEs/OH-PBDEs with zebrafish RARs and to identify binding affinities to analyze the specialization of the interaction between RARs and PBDEs/OH-PBDEs. The results showed that although these compounds could bind with RARs, the effects of PBDEs/OH-PBDEs on RAR transcriptional activity did not depend on their RAR-binding abilities. The present study is the first attempt to demonstrate that OH-PBDEs could induce RAR transcriptional activity by binding directly with RAR; these effects are possibly related to the structure of the compounds, especially their hydroxylation and bromination. Most of the PBDEs could not directly interact with the RAR.
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Affiliation(s)
- Jing Zhao
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Technology, Tongji University, Shanghai, 200092, China
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25
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Yamaguchi A, Kato K, Arizono K, Tominaga N. Induction of the estrogen-responsive genes encoding choriogenin H and L in the liver of male medaka (Oryzias latipes) upon exposure to estrogen receptor subtype-selective ligands. J Appl Toxicol 2014; 35:752-8. [DOI: 10.1002/jat.3063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 01/20/2023]
Affiliation(s)
- Akemi Yamaguchi
- Department of Chemical and Biological Engineering; Ariake National College of Technology; 150 Higashihagio-machi Omuta Fukuoka 836-8585 Japan
| | - Keisuke Kato
- Faculty of Pharmaceutical Sciences; Toho University; 2-2-1 Miyama Funabashi Chiba 274-8510 Japan
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences; Prefectural University of Kumamoto; 3-1-10 Tsukide Kumamoto 862-8502 Japan
| | - Nobuaki Tominaga
- Department of Chemical and Biological Engineering; Ariake National College of Technology; 150 Higashihagio-machi Omuta Fukuoka 836-8585 Japan
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26
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Cohen SP, LaChappelle AR, Walker BS, Lassiter CS. Modulation of estrogen causes disruption of craniofacial chondrogenesis in Danio rerio. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 152:113-120. [PMID: 24747083 DOI: 10.1016/j.aquatox.2014.03.028] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Revised: 03/30/2014] [Accepted: 03/31/2014] [Indexed: 06/03/2023]
Abstract
Estrogen is a steroid hormone that is ubiquitous in vertebrates, but its role in cartilage formation has not been extensively studied. Abnormalities of craniofacial cartilage and bone account for a large portion of birth defects in the United States. Zebrafish (Danio rerio) have been used as models of human disease, and their transparency in the embryonic period affords additional advantages in studying craniofacial development. In this study, zebrafish embryos were treated with 17-β estradiol (E2) or with an aromatase inhibitor and observed for defects in craniofacial cartilage. Concentrations of E2 greater than 2μM caused major disruptions in cartilage formation. Concentrations below 2μM caused subtle changed in cartilage morphology that were only revealed by measurement. The angles formed by cartilage elements in fish treated with 1.5 and 2μM E2 were increasingly wide, while the length of the primary anterior-posterior cartilage element in these fish decreased significantly from controls. These treatments resulted in fish with shorter, flatter faces as estrogen concentration increased. Inhibition of aromatase activity also resulted in similar craniofacial disruption indicating that careful control of estrogen signaling is required for appropriate development. Further investigation of the phenomena described in this study could lead to a better understanding of the etiology of craniofacial birth defects and endocrine disruption of cartilage formation.
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Affiliation(s)
- Sarah P Cohen
- Department of Biology, Roanoke College, 221 College Lane, Salem, VA 24153, USA
| | - Adam R LaChappelle
- Department of Biology, Roanoke College, 221 College Lane, Salem, VA 24153, USA
| | - Benjamin S Walker
- Department of Biology, Roanoke College, 221 College Lane, Salem, VA 24153, USA
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27
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Bondesson M, Hao R, Lin CY, Williams C, Gustafsson JÅ. Estrogen receptor signaling during vertebrate development. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:142-51. [PMID: 24954179 DOI: 10.1016/j.bbagrm.2014.06.005] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/09/2014] [Accepted: 06/10/2014] [Indexed: 01/03/2023]
Abstract
Estrogen receptors are expressed and their cognate ligands produced in all vertebrates, indicative of important and conserved functions. Through evolution estrogen has been involved in controlling reproduction, affecting both the development of reproductive organs and reproductive behavior. This review broadly describes the synthesis of estrogens and the expression patterns of aromatase and the estrogen receptors, in relation to estrogen functions in the developing fetus and child. We focus on the role of estrogens for the development of reproductive tissues, as well as non-reproductive effects on the developing brain. We collate data from human, rodent, bird and fish studies and highlight common and species-specific effects of estrogen signaling on fetal development. Morphological malformations originating from perturbed estrogen signaling in estrogen receptor and aromatase knockout mice are discussed, as well as the clinical manifestations of rare estrogen receptor alpha and aromatase gene mutations in humans. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
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Affiliation(s)
- Maria Bondesson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, TX, USA.
| | - Ruixin Hao
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, USA; DuPont Haskell Global Centers for Health and Environmental Sciences, Newark, DE, USA
| | - Chin-Yo Lin
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, TX, USA
| | - Cecilia Williams
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, TX, USA
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, TX, USA; Department of Biosciences and Nutrition, Karolinska Institutet, 14183 Huddinge, Sweden
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28
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Nagasawa K, Presslauer C, Kirtiklis L, Babiak I, Fernandes JMO. Sexually dimorphic transcription of estrogen receptors in cod gonads throughout a reproductive cycle. J Mol Endocrinol 2014; 52:357-71. [PMID: 24647045 DOI: 10.1530/jme-13-0187] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The role of sex steroid regulation in gonadal maturation is a very complex process that is far from being fully understood. Hence, we have investigated seasonal changes in gonadal expression of estrogen receptors (ERs) in Atlantic cod (Gadus morhua L.), a batch spawner, throughout the annual reproductive cycle. Three nuclear ER partial cDNA sequences (esr1, esr2a, and esr2b) were cloned and all esr transcripts were detected mainly in liver and gonads of fish of both sexes. In situ hybridization of esrs along with germ cell (vasa) and gonadal somatic cell markers (gonadal soma-derived factor (gsdf), 3β-hydroxysteroid dehydrogenase (3βhsd), and anti-Müllerian hormone (amh) for testicular, or gsdf for ovarian somatic cells) showed that all three esrs were preferentially localized within interstitial fibroblasts composed of immature and mature Leydig cells in testis, whereas they were differentially expressed in both follicular cells and oocytes in ovary. Quantitative real-time PCR analysis revealed a sexually dimorphic expression pattern of the three esr paralogs in testis and ovary. A significant increase in esr2a expression was identified in testis and of esr2b in ovary, whereas esr1 transcripts were elevated in both testis and ovary in February and March before the spawning period. The localization and sexually dimorphic expression of esr genes in gonads indicate a direct function of estrogen via ERs in gonadal somatic cell growth and differentiation for Leydig cell in testis and follicular cells in ovary throughout the annual reproductive cycle in Atlantic cod.
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Affiliation(s)
- Kazue Nagasawa
- Faculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland
| | - Christopher Presslauer
- Faculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland
| | - Lech Kirtiklis
- Faculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, PolandFaculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland
| | - Igor Babiak
- Faculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland
| | - Jorge M O Fernandes
- Faculty of Biosciences and AquacultureUniversity of Nordland, 8049 Bodø, NorwayDepartment of ZoologyFaculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland
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29
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Hao R, Bondesson M, Singh AV, Riu A, McCollum CW, Knudsen TB, Gorelick DA, Gustafsson JÅ. Identification of estrogen target genes during zebrafish embryonic development through transcriptomic analysis. PLoS One 2013; 8:e79020. [PMID: 24223173 PMCID: PMC3819264 DOI: 10.1371/journal.pone.0079020] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 09/17/2013] [Indexed: 12/26/2022] Open
Abstract
Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post fertilization (dpf), harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP)). Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database). The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific.
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Affiliation(s)
- Ruixin Hao
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Maria Bondesson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
- * E-mail:
| | - Amar V. Singh
- National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, United States of America
| | - Anne Riu
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Catherine W. McCollum
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Thomas B. Knudsen
- National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, United States of America
| | - Daniel A. Gorelick
- Department of Embryology, Carnegie Institute for Science, Baltimore, Maryland, United States of America
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
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30
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Griffin LB, January KE, Ho KW, Cotter KA, Callard GV. Morpholino-mediated knockdown of ERα, ERβa, and ERβb mRNAs in zebrafish (Danio rerio) embryos reveals differential regulation of estrogen-inducible genes. Endocrinology 2013; 154:4158-69. [PMID: 23928376 PMCID: PMC3800766 DOI: 10.1210/en.2013-1446] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Genetically distinct estrogen receptor (ER) subtypes (ERα and ERβ) play a major role in mediating estrogen actions in vertebrates, but their unique and overlapping functions are not entirely clear. Although mammals have 1 gene of each subtype (ESR1 and ESR2), teleost fish have a single esr1 (ERα) and 2 esr2 (ERβa and ERβb) genes. To determine the in vivo role of different ER isoforms in regulating estrogen-inducible transcription targets, zebrafish (Danio rerio) embryos were microinjected with esr-specific morpholino (MO) oligonucleotides to disrupt splicing of the exon III/intron III junction in the DNA-binding domain. Each MO knocked down its respective normal transcript and increased production of variants with a retained intron III (esr1 MO) or a deleted or mis-spliced exon III (esr2a and esr2b MOs). Both esr1 and esr2b MOs blocked estradiol induction of vitellogenin and ERα mRNAs, predominant hepatic genes, but esr2b was the only MO that blocked induction of cytochrome P450 aromatase B mRNA, a predominant brain gene. Knockdown of ERβa with the esr2a MO had no effect on estrogen induction of the 3 mRNAs but, when coinjected with esr1 MO, attenuated the effect of ERα knockdown. Results indicate that ERα and ERβb, acting separately or cooperatively on specific gene targets, are positive transcriptional regulators of estrogen action, but the role of ERβa, if any, is unclear. We conclude that MO technology in zebrafish embryos is an advantageous approach for investigating the interplay of ER subtypes in a true physiological context.
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Affiliation(s)
- Lucinda B Griffin
- Department of Biology, Boston University, 5 Cummington Mall, Boston, Massachusetts 02215.
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31
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Nelson ER, Habibi HR. Estrogen receptor function and regulation in fish and other vertebrates. Gen Comp Endocrinol 2013; 192:15-24. [PMID: 23583769 DOI: 10.1016/j.ygcen.2013.03.032] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 03/27/2013] [Accepted: 03/31/2013] [Indexed: 01/08/2023]
Abstract
Estrogens, steroid hormones critically involved in reproductive processes of vertebrates, signal primarily through their intracellular estrogen receptors (ERs). The ERs belong to a superfamily of nuclear receptors that act as ligand inducible transcription factors. Herein, we review what is known about ER structure, subtypes, mechanism(s) of action and auto-regulation by estrogens. Focus is placed on the ER in fish but comparisons are made to mammals and other vertebrates. Finally, we provide context and a proposed model integrating our knowledge on autoregulation of the receptor and its functions in the liver. Future areas of study are suggested, along with cautions when designing experiments, especially for the detection of endocrine disruptors.
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Affiliation(s)
- Erik R Nelson
- Pharmacology and Cancer Biology, Duke University School of Medicine, LSRC Bldg, Research Drive, Durham, NC 27710, United States.
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32
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Mu W, Wen H, Shi D, Yang Y. Molecular cloning and expression analysis of estrogen receptor betas (ERβ1 and ERβ2) during gonad development in the Korean rockfish, Sebastes schlegeli. Gene 2013; 523:39-49. [DOI: 10.1016/j.gene.2013.03.109] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 03/20/2013] [Accepted: 03/25/2013] [Indexed: 10/26/2022]
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33
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Raingeard D, Bilbao E, Cancio I, Cajaraville MP. Retinoid X receptor (RXR), estrogen receptor (ER) and other nuclear receptors in tissues of the mussel Mytilus galloprovincialis: Cloning and transcription pattern. Comp Biochem Physiol A Mol Integr Physiol 2013; 165:178-90. [DOI: 10.1016/j.cbpa.2013.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 02/25/2013] [Accepted: 03/02/2013] [Indexed: 01/11/2023]
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34
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Huang GY, Ying GG, Liang YQ, Liu YS, Liu SS. Effects of steroid hormones on reproduction- and detoxification-related gene expression in adult male mosquitofish, Gambusia affinis. Comp Biochem Physiol C Toxicol Pharmacol 2013; 158:36-43. [PMID: 23665278 DOI: 10.1016/j.cbpc.2013.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 05/02/2013] [Accepted: 05/02/2013] [Indexed: 12/30/2022]
Abstract
The molecular mechanisms that mediate fish reproduction and detoxification in response to steroid hormones were studied by using adult male western mosquitofish (Gambusia affinis) as sentinel species. The expression patterns of three vitellogenins (VtgA, VtgB and VtgC), two estrogen receptors (ERα and ERβ), two androgen receptors (ARα and ARβ), metallothionein (MT) and cytochrome P450 1A (CYP1A) in the liver and testis of adult male mosquitofish were assessed through exposure treatments with progesterone (P), testosterone (T) and 17β-estradiol (E2), alone and in combination for eight days. The results showed that expression patterns of Vtg subtype, ER subtype, AR subtype, MT and CYP1A genes in male mosquitofish varied according to tissue and specific hormone stress. Vtg subtype mRNA expression was induced in the liver in E2-added treatments, and an up-regulation of ERα mRNA expression was also observed. In addition, hormone treatments increased three Vtg subtype mRNA expression levels in the testis, at least to some extent. All hormone treatments significantly inhibited ERα, ERβ and ARβ mRNA expression in the testis. Some of hormone treatments could affect MT and CYP1A gene expression in mosquitofish. In general, multiple hormone treatments showed different effects on target gene expression compared with corresponding hormone alone. The results from the present study provided valuable information on the toxicological effects of steroid hormones in mosquitofish.
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Affiliation(s)
- Guo-Yong Huang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
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35
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Li W, Zhang J, Mu W, Wen H. Cloning, characterization and expression of estrogen receptor beta in the male half-smooth tongue sole, Cynoglossus semilaevis. FISH PHYSIOLOGY AND BIOCHEMISTRY 2013; 39:671-682. [PMID: 23053612 DOI: 10.1007/s10695-012-9729-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 09/25/2012] [Indexed: 06/01/2023]
Abstract
A full-length sequence encoding the estrogen receptor beta was isolated from half-smooth tongue sole, Cynoglossus semilaevis (hstsERβ) using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends procedures. The hstsERβ cDNA clone was found to contain 1,791 nucleotides including an open reading frame that encodes 578 amino acids. The deduced hstsERβ protein consisted of six nuclear receptor-characteristic domains. Based on a phylogenetic analysis, the hstsERβ C and E domains are highly conserved compared to other fishes. The potential phosphorylation sites for PKC, CK-2 and PTK are also found in this protein. Highest amino acid identities were found for hstsERβ with common carp (Cyprinus carpio) ERβ (76 %) and Japanese flounder (Paralichthys olivaceus) ERβ (76 %). Tissue expression analysis confirmed that the hstsERβ was widely distributed and predominantly expressed in testis, brain and liver. Seasonal changes in the testis, brain and liver expression profiles of hstsERβ were examined by RT-PCR; the present results suggest that level of hstsERβ in brain increased to the highest then decreases with gonadal growth; whereas in the testis and liver, the hstsERβ mRNA level dropped to lowest then slightly increased.
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Affiliation(s)
- Wenge Li
- Fisheries College, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
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36
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Pinto PIS, Teodósio R, Socorro S, Power DM, Canário AVM. Structure, tissue distribution and estrogen regulation of splice variants of the sea bream estrogen receptor α gene. Gene 2012; 503:18-24. [PMID: 22579469 DOI: 10.1016/j.gene.2012.04.081] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 04/15/2012] [Accepted: 04/26/2012] [Indexed: 01/27/2023]
Abstract
Estrogen actions are mainly mediated by specific nuclear estrogen receptors (ERs), for which different genes and a diversity of transcript variants have been identified, mainly in mammals. In this study, we investigated the presence of ER splice variants in the teleost fish gilthead sea bream (Sparus auratus), by comparison with the genomic organization of the related species Takifugu rubripes. Two exon2-deleted ERα transcript variants were isolated from liver cDNA of estradiol-treated fish. The ΔE2 variant lacks ERα exon 2, generating a premature termination codon and a putative C-terminal truncated receptor, while the ΔE2,3* variant contains an in-frame deletion of exon 2 and part of exon 3 and codes for a putative ERα protein variant lacking most of the DNA-binding domain. Both variants were expressed at very low levels in several female and male sea bream tissues, and their expression was highly inducible in liver by estradiol-17β treatment with a strong positive correlation with the typical wild-type (wt) ERα response in this tissue. These findings identify novel estrogen responsive splice variants of fish ERα, and provide the basis for future studies to investigate possible modulation of wt-ER actions by splice variants.
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Affiliation(s)
- P I S Pinto
- University of Algarve, Campus de Gambelas, Faro, Portugal.
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Spachmo B, Arukwe A. Endocrine and developmental effects in Atlantic salmon (Salmo salar) exposed to perfluorooctane sulfonic or perfluorooctane carboxylic acids. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2012; 108:112-124. [PMID: 22265611 DOI: 10.1016/j.aquatox.2011.07.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 07/25/2011] [Accepted: 07/29/2011] [Indexed: 05/31/2023]
Abstract
In this study, we have investigated the effect of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) on endocrine signalling, growth and development in Atlantic salmon (Salmo salar) embryos and larvae. Expression of genes related to the hypothalamic-pituitary-thyroid (HPT) axis, growth-hormone/insulin-like growth factor (GH/IGF) axis and the steroid hormone axis were used as indicators of endocrine disruption. We also studied bone development in larvae, both by observing skeletal structure formation and by investigating expression of genes involved in ossification process. Atlantic salmon embryos, kept in plastic tanks at 5-7°C, were exposed to 100 μg/L PFOA or PFOS from egg stage for a period of 52 days, followed by one-week recovery period. Sampling was performed at day 21, 35, 49 and 56 representing age 549, 597, 679 and 721 dd (dd or day degrees = number of days × temperature in degree Celsius:°C). Note that day 56 or 721 dd is the end of the 1-week recovery period. Larvae were divided into designated head and body regions for the purpose of gene expression analysis, except for genes that regulate ossification that were analyzed in whole larvae. Expression of thyroid receptor α and β (TRα and TRβ), thyroid-stimulating hormone β (TSHβ), T(4) outer-ring deiodinase (T(4)ORD), growth hormone (GH), insulin-like growth factor-I and II (IGF-I and II), insulin-like growth factor I receptor (IGF-IR), and estrogen receptor α and β (ERα and ERβ) were investigated using quantitative PCR. Both PFOS and PFOA exposure produced non-significant alterations in larvae weight (except after the recovery period when a decrease was observed), while larvae length was unaffected. PFOS and PFOA exposure produced body- and head region-specific alterations in expression of all the investigated gene transcripts. Expression of IGF-I and IGF-IR paralleled that of GH, indicating that perturbation of GH expression is a possible end point for disruption of the GH-IGF axis. We did not observe developmental changes related to angiogenesis, ossification and chondrogenesis after exposure to PFOS and PFOA. Transcriptional abnormalities may serve as indicators of chronic exposure, although the concrete mechanisms causing the observed effects remain ambiguous. The implications of these findings for the complete lifecycle, including other developmental and/or reproductive damage, are areas of future study.
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Affiliation(s)
- Bård Spachmo
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
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38
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Jeng SR, Pasquier J, Yueh WS, Chen GR, Lee YH, Dufour S, Chang CF. Differential regulation of the expression of cytochrome P450 aromatase, estrogen and androgen receptor subtypes in the brain-pituitary-ovarian axis of the Japanese eel (Anguilla japonica) reveals steroid dependent and independent mechanisms. Gen Comp Endocrinol 2012; 175:163-72. [PMID: 22107840 DOI: 10.1016/j.ygcen.2011.11.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 10/31/2011] [Accepted: 11/04/2011] [Indexed: 11/15/2022]
Abstract
This study aimed at investigating the role of sexual steroids in the regulation of the expression of the single aromatase gene and steroid receptor subtypes in the brain-pituitary-ovarian axis of the Japanese eel. Unlike other teleosts, which possess duplicated genes for aromatase, cyp19a1a and cyp19a1b, expressed in the gonads and in the brain, respectively, eel species possess a single cyp19a1. Phylogenetic analysis indicated that eel brain/gonadal cyp19a1 branches at the basis of both teleost gonadal cyp19a1a and brain cyp19a1b clades. Female eels treated with catfish pituitary homogenate (CPH) to induce sexual maturation showed an increase in the expression of cyp19a1 and aromatase enzymatic activity in the brain and in the ovaries. Treatments with sex steroids (estradiol-17β, E(2) or testosterone, T) revealed that the increase in cyp19a1 expression in the brain may result from E(2)-specific induction. In contrast, the increase in cyp19a1 expression in the ovaries of CPH-treated eels is a result of steroid-independent control, probably from a direct effect of gonadotropins contained in the pituitary extract. Analysis of the expression of estrogen and androgen receptor subtypes, esr-α, esr-β, ar-α and ar-β, in eels treated with CPH or sex steroids revealed differential regulations. In CPH-treated eels, the expression of esr-α and ar-α was significantly increased in the brain, while the expression of ar-α and ar-β was increased in the ovaries. No change was observed in esr-β in any organ. Steroid treatments induced an upregulation by E(2) of esr-α, but not esr-β expression, in the brain, pituitary and ovaries, while no autoregulation by T of its own receptors could be observed. These results reveal both steroid-dependent and -independent mechanisms in the regulation of cyp19a1 and steroid receptor subtype expression in the eel.
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Affiliation(s)
- Shan-Ru Jeng
- Department of Aquaculture, National Kaohsiung Marine University, Kaohsiung 811, Taiwan.
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39
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Pri-Tal BM, Blue S, Pau FKY, Podrabsky JE. Hormonal components of altered developmental pathways in the annual killifish, Austrofundulus limnaeus. Gen Comp Endocrinol 2011; 174:166-74. [PMID: 21906598 DOI: 10.1016/j.ygcen.2011.08.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 08/18/2011] [Accepted: 08/21/2011] [Indexed: 10/17/2022]
Abstract
The annual killifish, Austrofundulus limnaeus, typically enters embryonic diapause at two distinct points of development, termed diapause II and III. This study explores the role of maternal and embryonic steroid hormones, including 17-β-estradiol (E2), androstenedione (A4) and testosterone (T), in regulating the developmental decision to enter or escape diapause II. Steroid hormone levels were measured in tissues isolated from adult female killifish during the normal lifespan of this species and in individuals of the same age that were producing either high or low proportions of escape embryos. Levels of steroid hormones were also measured during early development and in fertilized eggs that were predicted to be on either an escape or diapausing developmental trajectory. Decreases in maternal E2 levels associated with age are correlated with decreasing escape embryo production. Maternal production of escape embryos is correlated with increased ratios of E2 to T in adult ovary tissue. Interestingly, neither hormone is significantly different in fish producing embryos on different developmental pathways when examined independently. Levels of steroid hormones in fertilized eggs are not correlated with entry or escape from diapause II, though levels of A4 tend to be higher in escape embryos. Escape embryos exhibit faster hormone metabolism and earlier hormone synthesis than embryos that will enter diapause II. Incubation of embryos in exogenous E2 is associated with a 7-fold increase in escape embryo production, and significantly elevated A4 levels. These data suggest that steroid hormones may be critical factors involved in determining developmental pathways in embryos of A. limnaeus.
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Affiliation(s)
- Benjamin M Pri-Tal
- Department of Biology, Portland State University, P.O. Box 751, Portland, OR 97207-0751, USA
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40
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Rüegg J, Cai W, Karimi M, Kiss NB, Swedenborg E, Larsson C, Ekström TJ, Pongratz I. Epigenetic regulation of glucose transporter 4 by estrogen receptor β. Mol Endocrinol 2011; 25:2017-28. [PMID: 22016564 DOI: 10.1210/me.2011-1054] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Glucose transporter 4 (Glut4) is an important regulator of cellular glucose uptake in adipose tissue and skeletal muscle. The estrogen receptors α and β (ERα and ERβ) have been shown to regulate Glut4. However, the regulatory mechanisms are unclear, and there are conflicting results about the effects of the two ER isoforms on Glut4 activity. In this study we investigated how the lack of either ER isoform affects Glut4 expression in differentiated mouse embryonic fibroblasts. Our results demonstrate that Glut4 transcription is markedly reduced in cells lacking ERβ, both basally and upon induction by liver X receptor. These changes in Glut4 expression could not be explained by the lack of ERβ as ligand-activated transcription factor. They were rather brought about by hypermethylation of one single CpG in the Glut4 promoter in the ERβ-deficient cells. This CpG is part of an Sp1-binding site, and Sp1 binding was reduced by its methylation. Treatment with Sp1 inhibitor diminished Glut4 expression in wild-type, but not in ERβ-deficient cells, suggesting that reduced recruitment of Sp1 to the Glut4 promoter is responsible for the differences in Glut4 expression. Reintroduction of ERβ into ERβ-deficient cells partly restored Glut4 transcription and stabilized low DNA methylation after treatment with the DNA demethylating agent 5-Aza-2'-deoxycytidine. Our findings demonstrate the involvement of DNA methylation in Glut4 regulation and imply a novel function for ERβ in mediating epigenetic events and thereby regulating gene expression.
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Affiliation(s)
- Joëlle Rüegg
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, 141 57 Sweden.
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41
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Chen H, Zhang Y, Li S, Lin M, Shi Y, Sang Q, Liu M, Zhang H, Lu D, Meng Z, Liu X, Lin H. Molecular cloning, characterization and expression profiles of three estrogen receptors in protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides). Gen Comp Endocrinol 2011; 172:371-81. [PMID: 21473869 DOI: 10.1016/j.ygcen.2011.03.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 03/18/2011] [Accepted: 03/27/2011] [Indexed: 11/29/2022]
Abstract
Estrogen plays key roles in vertebrate reproductive system via estrogen receptors (ERs) as mediating pathways. In the present study, three full-length ERs cDNA sequences were isolated from a protogynous teleost, the orange-spotted grouper (Epinephelus coioides), and were 2235bp for gERα, 1967bp for gERβ1 and 2158bp for gERβ2, respectively. Phylogenetic and amino acid alignment analyses showed that each gER was clustered in the corresponding taxonomic groups of the perciformes and exhibited high evolutional conservation in functional domains. RT-PCR revealed that gERs expressed at different levels in all the obtained tissues. gERα highly expressed in mature ovaries, gERβ1 mainly expressed in immature ovaries and gERβ2 varied greatly during ovarian development. During female to male sex reversal induced by 17α-methyltestosterone (MT) implantation, gERα decreased gradually, gERβ1 increased gradually, and gERβ2 decreased firstly and recovered subsequently in male stage. The present study speculated the potential roles of gERs during female maturation and female to male sex reversal induced by MT in the protogynous grouper E. coioides.
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Affiliation(s)
- Huapu Chen
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou, Guangdong, China
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42
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Abstract
Estrogens regulate a diverse range of physiological processes and affect multiple tissues. Estrogen receptors (ERs) regulate transcription by binding to DNA at conserved estrogen response elements, and such elements have been used to report ER activity in cultured cells and in transgenic mice. We generated stable, transgenic zebrafish containing five consecutive elements upstream of a c-fos minimal promoter and green fluorescent protein (GFP) to visualize and quantify transcriptional activation in live larvae. Transgenic larvae show robust, dose-dependent estrogen-dependent fluorescent labeling in the liver, consistent with er gene expression, whereas ER antagonists inhibit GFP expression. The nonestrogenic steroids dexamethasone and progesterone fail to activate GFP, confirming ER selectivity. Natural and synthetic estrogens activated the transgene with varying potency, and two chemicals, genistein and bisphenol A, preferentially induce GFP expression in the heart. In adult fish, fluorescence was observed in estrogenic tissues such as the liver, ovary, pituitary gland, and brain. Individual estrogen-responsive neurons and their projections were visualized in the adult brain, and GFP-positive neurons increased in number after 17β-estradiol exposure. The transgenic estrogen-responsive zebrafish allow ER signaling to be monitored visually and serve as in vivo sentinels for detection of estrogenic compounds.
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Affiliation(s)
- Daniel A Gorelick
- Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive, Baltimore, Maryland 21218, USA.
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43
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Celeghin A, Benato F, Pikulkaew S, Rabbane MG, Colombo L, Dalla Valle L. The knockdown of the maternal estrogen receptor 2a (esr2a) mRNA affects embryo transcript contents and larval development in zebrafish. Gen Comp Endocrinol 2011; 172:120-9. [PMID: 21199655 DOI: 10.1016/j.ygcen.2010.12.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 12/21/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
Abstract
In zebrafish, ovulated oocytes are loaded with maternal estrogen receptor 2a (esr2a) mRNA which is spread as granular and filamentous structures throughout the central ooplasm and is promptly relocated inside the blastodisc area at the 1-cell stage (0.2h post-fertilization, hpf), as shown by in situ hybridization. This transcript is available for translation until its sharp decline from 4 to 8 hpf, being replaced by low levels of zygotic esr2a mRNA mainly localized in the head region and around the yolk sac from 24 hpf until hatching at 48 hpf. To test the functional role of the maternal esr2a mRNA, 1- or 2-cell embryos were injected with 10.3 ng each of morpholino (MO) to knockdown translation (MO2-esr2a) of both maternal and zygotic esr2a transcripts, with a missplicing MO (MO3-esr2a) to effectively block post-transcriptionally the zygotic transcript alone, and with a non-specific MO-control. Treatment with MO2-esr2a increased apoptosis in embryos, especially in the brain, and caused severe malformations in 63% of 1-5 dpf larvae, as compared to 10-11% in those treated with MO3-esr2a and MO-control. Defects included body growth delay with curved shape, persistent yolk sac with reduced sub-intestinal veins and swollen yolk extension, abnormal brain and splanchnocranium development, smaller eyes and otic vesicles, pericardial oedema, uninflated swim bladder and rudimentary caudal fin with aberrant circular swimming. Affected larvae could survive for only 12-14 days. The MO2-esr2a phenotype was rescued with co-injection of 30 pg/embryo of mutated zebrafish esr2a mRNA encoding the full length of Esr2a, but containing eight silent mutations in the region recognised by MO2-esr2a. A lower dosage (15 pg) failed to recover mortality and abnormality. Raising the dosage to 60 and 90 pg increased abnormality, but not mortality, whereas with 120 pg both mortality and abnormality worsened, indicating a strict quantitative requirement of Esr2a. Co-injection of an anti-p53 MO failed to rescue the MO2-esr2a phenotype, eliminating the possibility of off-target effects. Pangenomic microarray analysis revealed that 240 and 219 significantly expressed transcripts were up- and down-regulated, respectively, by maternal Esr2a protein deficiency in 8-hpf MO2-esr2a embryos. Also at 48 hpf, 162 and 120 presumably zygotic transcripts were up- and down-regulated, respectively, but only 18 were in common with each of the 8-hpf sets. In total, the transcripts from 705 genes were affected by Esr2a knockdown. These findings suggest the involvement of maternal esr2a mRNA, presumably transactivated by maternal 17β-estradiol stored in the oocyte from enveloping granulosa cells, in the epigenetic programming of zebrafish development.
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MESH Headings
- Animals
- Animals, Genetically Modified
- Cartilage/embryology
- Cartilage/growth & development
- Cartilage/metabolism
- Embryo, Nonmammalian/chemistry
- Embryo, Nonmammalian/metabolism
- Epigenesis, Genetic/physiology
- Estrogen Receptor beta
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Gene Knockdown Techniques
- Larva/genetics
- Larva/growth & development
- Larva/metabolism
- Microarray Analysis
- Phenotype
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Messenger, Stored/antagonists & inhibitors
- RNA, Messenger, Stored/genetics
- Receptors, Estrogen/antagonists & inhibitors
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Validation Studies as Topic
- Zebrafish/embryology
- Zebrafish/genetics
- Zebrafish/growth & development
- Zebrafish/metabolism
- Zebrafish Proteins/antagonists & inhibitors
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism
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Affiliation(s)
- Andrea Celeghin
- Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy
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44
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Hunter SE, Jung D, Di Giulio RT, Meyer JN. The QPCR assay for analysis of mitochondrial DNA damage, repair, and relative copy number. Methods 2010; 51:444-51. [PMID: 20123023 PMCID: PMC2912960 DOI: 10.1016/j.ymeth.2010.01.033] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Accepted: 01/26/2010] [Indexed: 11/25/2022] Open
Abstract
The quantitative polymerase chain reaction (QPCR) assay allows measurement of DNA damage in the mitochondrial and nuclear genomes without isolation of mitochondria. It also permits measurement of relative mitochondrial genome copy number. Finally, it can be used for measurement of DNA repair in vivo when employed appropriately. In this manuscript we briefly review the methodology of the QPCR assay, discuss its strengths and limitations, address considerations for measurement of mitochondrial DNA repair, and describe methodological changes implemented in recent years. We present QPCR assay primers and reaction conditions for five species not previously described in a methods article: Caenorhabditis elegans, Fundulus heteroclitus, Danio rerio, Drosophila melanogaster, and adenovirus. Finally, we illustrate the use of the assay by measuring repair of ultraviolet C radiation-induced DNA damage in the nuclear but not mitochondrial genomes of a zebrafish cell culture.
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Affiliation(s)
- Senyene E Hunter
- Nicholas School of the Environment, Duke University, Durham, NC 27708-0328, USA
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45
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Marlatt VL, Lakoff J, Crump K, Martyniuk CJ, Watt J, Jewell L, Atkinson S, Blais JM, Sherry J, Moon TW, Trudeau VL. Sex- and tissue-specific effects of waterborne estrogen on estrogen receptor subtypes and E2-mediated gene expression in the reproductive axis of goldfish. Comp Biochem Physiol A Mol Integr Physiol 2010; 156:92-101. [DOI: 10.1016/j.cbpa.2010.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 12/31/2009] [Accepted: 01/02/2010] [Indexed: 01/06/2023]
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Smolinsky AN, Doughman JM, Kratzke LTC, Lassiter CS. Zebrafish (Danio rerio) androgen receptor: sequence homology and up-regulation by the fungicide vinclozolin. Comp Biochem Physiol C Toxicol Pharmacol 2010; 151:161-6. [PMID: 19818413 DOI: 10.1016/j.cbpc.2009.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 10/01/2009] [Accepted: 10/02/2009] [Indexed: 11/24/2022]
Abstract
Steroid hormones regulate gene expression in organisms by binding to receptor proteins. These hormones include the androgens, which signal through androgen receptors (ARs). Endocrine disrupters (EDCs) are chemicals in the environment that adversely affect organisms by binding to nuclear receptors, including ARs. Vinclozolin, a fungicide used on fruit and vegetable crops, is a known anti-androgen, a type of EDC that blocks signals from testosterone and its derivatives. In order to better understand the effects of EDCs, further research on androgen receptors and other hormone signaling pathways is necessary. In this study, we demonstrate the evolutionary conservation between the genomic structure of the human and zebrafish ar genes and find that ar mRNA expression increases in zebrafish embryos exposed to vinclozolin, which may be evolutionarily conserved as well. At 48 and 72 h post-fertilization, vinclozolin-treated embryos express ar mRNA 8-fold higher than the control level. These findings suggest that zebrafish embryos attempt to compensate for the presence of an anti-androgen by increasing the number of androgen receptors available.
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47
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Christen V, Hickmann S, Rechenberg B, Fent K. Highly active human pharmaceuticals in aquatic systems: A concept for their identification based on their mode of action. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 96:167-81. [PMID: 20053463 DOI: 10.1016/j.aquatox.2009.11.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Revised: 10/29/2009] [Accepted: 11/03/2009] [Indexed: 05/13/2023]
Abstract
Widespread occurrence of traces of pharmaceuticals (ng/L to microg/L) has been reported in aquatic systems. However, their effects on the environment and their environmental risks remain elusive. Generally, the acute toxicity towards non-target organisms has been assessed in laboratory experiments, but chronic toxicity studies have been performed only rarely. The guideline issued by the European Medicines Agency in 2006 is aimed at estimating the potential environmental risks of human pharmaceuticals by a tiered approach. The predicted environmental concentration (PEC) of a compound is estimated in phase I, and pharmaceuticals having a PEC above or equal 10ng/L undergo phase II testing. Otherwise they are not expected to pose a risk to the environment. Because some highly active compounds (HC) such as 17-alpha-ethinylestradiol, equine estrogens, trenbolone and the progestin levonorgestrel display adverse effects at concentrations below 10ng/L the question arises, whether additional HC compounds exist, and how they can be identified for undergoing environmental risk assessment. We addressed this question by searching for HC in the literature, and by developing a concept for identification of HC. The suggested mode of action concept is based on (i) the mode of action of the pharmaceutical taking the available toxicological information into account, (ii) the degree of sequence homology between the human drug target and the potential target in aquatic organisms and (iii) the importance of pathways affected by the pharmaceutical. We evaluated the mode of action concept by comparison to existing approaches, the fish plasma model (Huggett et al., 2003) and a QSAR model, called VirtualTox Lab (www.biograf.ch). All concepts result in similar classifications of the selected pharmaceuticals. However, there are some differences not only in the model assumptions, but also in its results. Our study leads to the conclusion that the mode of action concept is most suitable for the identification of HC. A refinement can be achieved by complementing this concept by the QSAR model (VirtualTox Lab), whereas the fish plasma model seemed to be less suitable due to the necessity of environmental concentration above 10ng/L for the identification of a risk.
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Affiliation(s)
- Verena Christen
- University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland
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48
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Mouriec K, Lareyre JJ, Tong SK, Le Page Y, Vaillant C, Pellegrini E, Pakdel F, Chung BC, Kah O, Anglade I. Early regulation of brain aromatase (cyp19a1b) by estrogen receptors during zebrafish development. Dev Dyn 2010; 238:2641-51. [PMID: 19718764 DOI: 10.1002/dvdy.22069] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Early expression of estrogen receptors (esr) and their role in regulating early expression of cyp19a1b encoding brain aromatase were examined in the brain of zebrafish. Using in toto hybridization and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), a significant increase in the expression of esr1, esr2a, and esr2b was observed between 24 and 48 hours postfertilization (hpf). In toto hybridization demonstrated that esr2a and esr2b, but not esr1, are found in the hypothalamus. Using real-time RT-PCR, an increase in cyp19a1b mRNAs occurs between 24 and 48 hpf, indicating that expression of cyp19a1b is temporally correlated with that of esr. This increase is blocked by the pure anti-estrogen ICI182,780. Furthermore, E2 treatment of cyp19a1b-GFP (green fluorescent protein) transgenic embryos results in appearance of GFP expression in the brain as early as 25 hpf. These results indicate that basal expression of cyp19a1b expression in the brain of developing zebrafish most likely relies upon expression of esr that are fully functional before 25 hpf.
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Affiliation(s)
- K Mouriec
- Neurogenesis And OEstrogens, UMR CNRS 6026, IFR 140, Université de Rennes 1, Rennes, France
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49
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Pikulkaew S, De Nadai A, Belvedere P, Colombo L, Dalla Valle L. Expression analysis of steroid hormone receptor mRNAs during zebrafish embryogenesis. Gen Comp Endocrinol 2010; 165:215-20. [PMID: 19576895 DOI: 10.1016/j.ygcen.2009.06.024] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Revised: 05/14/2009] [Accepted: 06/28/2009] [Indexed: 11/27/2022]
Abstract
We have analyzed by qRT-PCR and/or RT-PCR the abundance and degradation rate of maternal mRNAs for nine steroid hormone receptors and their possible replacement by corresponding embryonic transcripts in both ovulated oocytes and embryos of zebrafish collected at 0, 1, 2, 4, 8, 12, 24 and 48 h post-fertilization (hpf). The mRNAs encoded the nuclear receptors for progesterone (pr), androgen (ar), estrogen (er alpha, er beta 1 and er beta 2), glucocorticoids (gr), mineralocorticoids (mr) and the membrane progestin receptor-alpha and beta (mpr alpha and beta). gr mRNA was the most abundant maternal transcript in oocytes and early embryos followed by er beta 2 and ar mRNAs. They declined during the first 8 hpf, being replaced, thereafter, by the embryonic messengers. er beta 1 and mr transcript levels were low until 8 hpf, but increased steadily during embryonic transcription from 24 to 48 hpf. pr transcripts were detectable only in ovulated oocytes and at 24 and 48 hpf. At these stages, there was a slight increase of er alpha mRNA that initially was very low. mPr alpha and beta mRNAs were expressed in ovulated oocytes and faintly persisted during the first 4 hpf. There was no subsequent embryonic expression of these transcripts. The possible involvement of maternal mRNAs for glucocorticoid and sex hormone receptors in the programming of early zebrafish development is intriguing, since they mainly occur at stages in which gene replication predominates over transcription.
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Affiliation(s)
- S Pikulkaew
- Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy
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50
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Single nucleotide polymorphisms within the estrogen receptor beta gene are linked with reproductive indices in Japanese flounder, Paralichthys olivaceus. Comp Biochem Physiol B Biochem Mol Biol 2009; 154:62-7. [PMID: 19427917 DOI: 10.1016/j.cbpb.2009.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 05/02/2009] [Accepted: 05/02/2009] [Indexed: 11/23/2022]
Abstract
The objectives of this study were to characterize polymorphisms within the coding region of estrogen receptor beta (ERbeta) gene in a population of 57 female Japanese flounder (Paralichthys olivaceus) and to analyze the association of ERbeta polymorphisms with reproductive indices by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). Two single nucleotide polymorphisms (SNPs), SNP1 (c.577delC) and SNP2 [c.A891T (p.Gln114Leu)], were identified in the ERbeta gene. A one-way ANOVA revealed that SNP1 was significantly associated with the gonadosomatic index (GSI) in female Japanese flounder (P < 0.05). And SNP2 was significantly associated with the serum 17beta-estradiol (E2) level and GSI (P < 0.05). Individuals with genotype AB of SNP2 had significantly higher serum E2 level and GSI than those of genotype AA (P < 0.05). Moreover, the hepatosomatic index (HSI), a marker for genetic effects, was significantly higher for diplotype D2 compared with the other three diplotypes (P < 0.05). These results obtained in this study suggested that SNP2 could influence reproductive endocrinology of female Japanese flounder and be useful as a potential candidate genetic marker for the selection of reproductive indices in female Japanese flounder.
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