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Pereira IL, Lopes C, Rocha E, Madureira TV. Establishing brown trout primary hepatocyte spheroids as a new alternative experimental model-Testing the effects of 5α-dihydrotestosterone on lipid pathways. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 253:106331. [PMID: 36327687 DOI: 10.1016/j.aquatox.2022.106331] [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: 07/06/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Three-dimensional (3D) fish liver cultures mimic the in vivo cellular microenvironment, which is ideal for ecotoxicological research. Despite that, the application of these cultures to evaluate toxic effects in fish is scarce. A 3D model of brown trout (Salmo trutta f. fario) primary hepatocyte spheroids was optimized in this study by using DMEM/F-12 with 15 mM of HEPES, 10 mL/L of an antibiotic and antimycotic solution and FBS 10% (v/v), at 18 °C with ∼100 rpm. The selection of optimal conditions was based on a multiparametric characterization of the spheroids, including biometry, viability, microanatomy and immunohistochemistry. Biometric and morphologic stabilization of spheroids was reached within 12-16 days of culture. To our knowledge, this study is the first to culture and characterize viable spheroids from brown trout primary hepatocytes for over 30 days. Further, the 3D model was tested to explore the androgenic influences on lipidic target genes after 96 h exposures to control, solvent control, 10 and 100 µM of 5α-dihydrotestosterone (DHT), a non-aromatizable androgen. Spheroids exposed to 100 µM of DHT had decreased sphericity. DHT at 100 µM also significantly down-regulated Acox1-3I, PPARγ and fatty acid synthesis targets (i.e., ACC), and significantly up-regulated Fabp1. Acsl1 was significantly up-regulated after exposure to both 10 and 100 µM of DHT. The results support that DHT modulates distinct lipidic pathways in brown trout and show that this 3D model is a new valuable tool for physiological and toxicological mechanistic studies.
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Affiliation(s)
- Inês L Pereira
- Histomorphology, Physiopathology and Applied Toxicology Team, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Laboratory of Histology and Embryology, Department of Microscopy, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (U.Porto), Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Célia Lopes
- Histomorphology, Physiopathology and Applied Toxicology Team, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Laboratory of Histology and Embryology, Department of Microscopy, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (U.Porto), Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Eduardo Rocha
- Histomorphology, Physiopathology and Applied Toxicology Team, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Laboratory of Histology and Embryology, Department of Microscopy, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (U.Porto), Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Tânia V Madureira
- Histomorphology, Physiopathology and Applied Toxicology Team, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Laboratory of Histology and Embryology, Department of Microscopy, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (U.Porto), Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
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Wang Y, Liu Z, Liu C, Liu R, Yang C, Wang L, Song L. Cortisol modulates glucose metabolism and oxidative response after acute high temperature stress in Pacific oyster Crassostrea gigas. FISH & SHELLFISH IMMUNOLOGY 2022; 126:141-149. [PMID: 35561949 DOI: 10.1016/j.fsi.2022.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 05/03/2022] [Accepted: 05/08/2022] [Indexed: 06/15/2023]
Abstract
Cortisol is the main stress hormone that plays crucial roles in energy metabolism and immune response in vertebrates. In the present study, the homologues of 11β-hydroxysteroid dehydrogenase type 1 (designated Cg11β-HSD1) and 5α-reductase 1 (designated Cg5αR1), the key enzymes related to cortisol metabolism, were identified from Pacific oyster Crassostrea gigas. The Cg11β-HSD1 harbored a conserved SDR domain, and Cg5αR1 contained a Steroid_dh domain and three transmembrane domains. The mRNA transcripts of Cg11β-HSD1 and Cg5αR1 were constitutively expressed in all the examined tissues of oysters, with the highest expression level in haemocytes and labial palp, respectively. After acute high temperature stress (28 °C), the mRNA expression level of Cg11β-HSD1 in hepatopancreas significantly up-regulated at 6 h and 12 h, and that of Cg5αR1 significantly up-regulated at 6 h, compared with the Blank group (11 °C). The concentration of cortisol and glucose, as well as the activities of superoxide dismutase (SOD) and catalase (CAT) in hepatopancreas all significantly up-regulated after acute high temperature stress, while the glycogen concentration in adductor muscle decreased significantly at 6 h and 12 h. After the blockage of Cg11β-HSD1 with metyrapone, the cortisol concentration and the activities of SOD and CAT significantly decreased after acute high temperature stress, the glucose concentration in hepatopancreas significantly increased at 24 h, and the glycogen concentration in adductor muscle significantly increased at 6 h. These results collectively suggested that cortisol played a crucial role in regulating glucose metabolism and oxidative response in oysters upon acute high temperature stress.
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Affiliation(s)
- Yuting Wang
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Zhaoqun Liu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Chang Liu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
| | - Ranyang Liu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Chuanyan Yang
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Lingling Wang
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
| | - Linsheng Song
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
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Development of a Liquid Chromatography/Mass Spectrometry-Based Inhibition Assay for the Screening of Steroid 5-α Reductase in Human and Fish Cell Lines. Molecules 2021; 26:molecules26040893. [PMID: 33567691 PMCID: PMC7915527 DOI: 10.3390/molecules26040893] [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: 12/11/2020] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 11/22/2022] Open
Abstract
Steroid 5-α reductase (5AR) is responsible for the reduction of steroids to 5-α reduced metabolites, such as the reduction of testosterone to 5-α dihydrotestosterone (DHT). A new adverse outcome pathway (AOP) for 5AR inhibition to reduce female reproduction in fish (AOP 289) is under development to clarify the antiestrogenic effects of 5AR inhibitors in female fish. A sensitive method for the DHT analysis using chemical derivatization and liquid chromatography–tandem mass spectrometry was developed. A cell-based 5AR inhibition assay that utilizes human cell lines, a transient overexpression system, and fish cell lines was developed. The measured IC50 values of two well-known 5AR inhibitors, finasteride and dutasteride, were comparable in the different systems. However, the IC50 of dutasteride in the fish cell lines was lower than that in the human cell lines. Finasteride showed a higher IC50 against the RTG-2 cell line. These results demonstrated that 5ARs inhibition could differ in terms of structural characteristics among species. The assay has high sensitivity and reproducibility and is suitable for the application in 5AR inhibition screening for various endocrine disruption chemicals (EDCs). Future studies will continue to evaluate the quantitative inhibition of 5AR by EDCs to compare the endocrine-disrupting pathway in different species.
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Fontaine R, Royan MR, von Krogh K, Weltzien FA, Baker DM. Direct and Indirect Effects of Sex Steroids on Gonadotrope Cell Plasticity in the Teleost Fish Pituitary. Front Endocrinol (Lausanne) 2020; 11:605068. [PMID: 33365013 PMCID: PMC7750530 DOI: 10.3389/fendo.2020.605068] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/12/2020] [Indexed: 12/26/2022] Open
Abstract
The pituitary gland controls many important physiological processes in vertebrates, including growth, homeostasis, and reproduction. As in mammals, the teleost pituitary exhibits a high degree of plasticity. This plasticity permits changes in hormone production and secretion necessary to meet the fluctuating demands over the life of an animal. Pituitary plasticity is achieved at both cellular and population levels. At the cellular level, hormone synthesis and release can be regulated via changes in cell composition to modulate both sensitivity and response to different signals. At the cell population level, the number of cells producing a given hormone can change due to proliferation, differentiation of progenitor cells, or transdifferentiation of specific cell types. Gonadotropes, which play an important role in the control of reproduction, have been intensively investigated during the last decades and found to display plasticity. To ensure appropriate endocrine function, gonadotropes rely on external and internal signals integrated at the brain level or by the gonadotropes themselves. One important group of internal signals is the sex steroids, produced mainly by the gonadal steroidogenic cells. Sex steroids have been shown to exert complex effects on the teleost pituitary, with differential effects depending on the species investigated, physiological status or sex of the animal, and dose or method of administration. This review summarizes current knowledge of the effects of sex steroids (androgens and estrogens) on gonadotrope cell plasticity in teleost anterior pituitary, discriminating direct from indirect effects.
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Affiliation(s)
- Romain Fontaine
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Muhammad Rahmad Royan
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kristine von Krogh
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Finn-Arne Weltzien
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Dianne M. Baker
- Department of Biological Sciences, University of Mary Washington, Fredericksburg, VA, United States
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Lopes C, Madureira TV, Gonçalves JF, Rocha E. Disruption of classical estrogenic targets in brown trout primary hepatocytes by the model androgens testosterone and dihydrotestosterone. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 227:105586. [PMID: 32882451 DOI: 10.1016/j.aquatox.2020.105586] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 07/13/2020] [Accepted: 07/28/2020] [Indexed: 06/11/2023]
Abstract
Estrogenic effects triggered by androgens have been previously shown in a few studies. Aromatization and direct binding to estrogen receptors (ERs) are the most proposed mechanisms. For example, previously, a modulation of vitellogenin A (VtgA) by testosterone (T), an aromatizable androgen, was reported in brown trout primary hepatocytes. The effect was reversed by an ER antagonist. In this study, using the same model the disruption caused by T and by the non-aromatizable androgen - dihydrotestosterone (DHT), was assessed in selected estrogenic targets. Hepatocytes were exposed (96 h) to six concentrations of each androgen. The estrogenic targets were VtgA, ERα, ERβ1 and two zona pellucida genes, ZP2.5 and ZP3a.2. The aromatase CYP19a1 gene and the androgen receptor (AR) were also included. Modulation of estrogenic targets was studied by quantitative real-time PCR and immunohistochemistry, using an HScore system. VtgA and ERα were up-regulated by DHT (1, 10, 100 μM) and T (10, 100 μM). In contrast, ERβ1 was down-regulated by DHT (10, 100 μM), and T (100 μM). ZP2.5 mRNA levels were increased by DHT and T (1, 10, 100 μM), while ZP3a.2 was up-regulated by DHT (100 μM) and T (10, 100 μM). Positive correlations were found between VtgA and ERα mRNA levels and ZPs and ERα, after exposure to both androgens. The mRNA levels of CYP19a1 were not changed, while AR expression tended to increase after micromolar DHT exposures. HScores for Vtg and ZPs corroborated the molecular findings. Both androgens triggered estrogen signaling through direct binding to ERs, most probably ERα.
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Affiliation(s)
- Célia Lopes
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, P 4450-208 Matosinhos, Portugal; Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - Tânia V Madureira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, P 4450-208 Matosinhos, Portugal; Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal.
| | - José F Gonçalves
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, P 4450-208 Matosinhos, Portugal; Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Department of Aquatic Production, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - Eduardo Rocha
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, P 4450-208 Matosinhos, Portugal; Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
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Rajakumar A, Senthilkumaran B. Steroidogenesis and its regulation in teleost-a review. FISH PHYSIOLOGY AND BIOCHEMISTRY 2020; 46:803-818. [PMID: 31940121 DOI: 10.1007/s10695-019-00752-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 12/23/2019] [Indexed: 06/10/2023]
Abstract
Steroid hormones modulate several important biological processes like metabolism, stress response, and reproduction. Steroidogenesis drives reproductive function wherein development and differentiation of undifferentiated gonads into testis or ovary, and their growth and maturation, are regulated. Steroidogenesis occurs in gonadal and non-gonadal tissues like head kidney, liver, intestine, and adipose tissue in teleosts. This process is regulated differently through multi-level modulation of promoter motif transcription factor regulation of steroidogenic enzyme genes to ultimately control enzyme activity and turnover. In view of this, understanding teleostean steroidogenesis provides major inputs for technological innovation of pisciculture. Unlike higher vertebrates, steroidal intermediates and shift in steroidogenesis is critical for gamete maturation in teleosts, more essentially oogenesis. Considering these characteristics, this review highlights the promoter regulation of steroidogenic enzyme genes by several transcription factors that are involved in teleostean steroidogenesis. It also addresses different methodologies involved in promoter regulation studies together with glucocorticoids and androgen relationship with reference to teleosts.
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Affiliation(s)
- Anbazhagan Rajakumar
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, Telangana, 500046, India
- Present Address: Section on Molecular Endocrinology, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, 20892,, USA
| | - Balasubramanian Senthilkumaran
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, Telangana, 500046, India.
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Oakes JA, Li N, Wistow BRC, Griffin A, Barnard L, Storbeck KH, Cunliffe VT, Krone NP. Ferredoxin 1b Deficiency Leads to Testis Disorganization, Impaired Spermatogenesis, and Feminization in Zebrafish. Endocrinology 2019; 160:2401-2416. [PMID: 31322700 DOI: 10.1210/en.2019-00068] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 07/13/2019] [Indexed: 01/08/2023]
Abstract
The roles of steroids in zebrafish sex differentiation, gonadal development, and function of the adult gonad are poorly understood. Herein, we used ferredoxin 1b (fdx1b) mutant zebrafish to explore such processes. Fdx1b is an essential electron-providing cofactor to mitochondrial steroidogenic enzymes, which are crucial for glucocorticoid and androgen production in vertebrates. Fdx1b-/- zebrafish mutants develop into viable adults in which concentrations of androgens and cortisol are significantly reduced. Adult fdx1b-/- mutant zebrafish display predominantly female secondary sex characteristics but may possess either ovaries or testes, confirming that androgen signaling is dispensable for testicular differentiation in this species, as previously demonstrated in androgen receptor mutant zebrafish. Adult male fdx1b-/- mutant zebrafish exhibit reduced characteristic breeding behaviors and impaired sperm production, resulting in infertility in standard breeding scenarios. However, eggs collected from wild-type females can be fertilized by the sperm of fdx1b-/- mutant males by in vitro fertilization. The testes of fdx1b-/- mutant males are disorganized and lack defined seminiferous tubule structure. Expression of several promale and spermatogenic genes is decreased in the testes of fdx1b-/- mutant males, including promale transcription factor sox9a and spermatogenic genes igf3 and insl3. This study establishes an androgen- and cortisol-deficient fdx1b zebrafish mutant as a model for understanding the effects of steroid deficiency on sex development and reproductive function. This model will be particularly useful for further investigation of the roles of steroids in spermatogenesis, gonadal development, and regulation of reproductive behavior, thus enabling further elucidation of the physiological consequences of endocrine disruption in vertebrates.
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Affiliation(s)
- James A Oakes
- Department of Oncology & Metabolism, School of Medicine, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Nan Li
- Department of Oncology & Metabolism, School of Medicine, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Belinda R C Wistow
- Department of Oncology & Metabolism, School of Medicine, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Aliesha Griffin
- Epilepsy Research Laboratory and Weill Institute for Neuroscience, Department of Neurologic Surgery, University of California, San Francisco, California
| | - Lise Barnard
- Department of Biochemistry, Stellenbosch University, Stellenbosch, Matieland, South Africa
| | - Karl-Heinz Storbeck
- Department of Biochemistry, Stellenbosch University, Stellenbosch, Matieland, South Africa
| | - Vincent T Cunliffe
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Nils P Krone
- Department of Oncology & Metabolism, School of Medicine, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
- Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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Porseryd T, Reyhanian Caspillo N, Volkova K, Elabbas L, Källman T, Dinnétz P, Olsson PE, Porsch-Hällström I. Testis transcriptome alterations in zebrafish (Danio rerio) with reduced fertility due to developmental exposure to 17α-ethinyl estradiol. Gen Comp Endocrinol 2018. [PMID: 29526718 DOI: 10.1016/j.ygcen.2018.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
17α-Ethinylestradiol (EE2) is a ubiquitous aquatic contaminant shown to decrease fish fertility at low concentrations, especially in fish exposed during development. The mechanisms of the decreased fertility are not fully understood. In this study, we perform transcriptome analysis by RNA sequencing of testes from zebrafish with previously reported lowered fertility due to exposure to low concentrations of EE2 during development. Fish were exposed to 1.2 and 1.6 ng/L (measured concentration; nominal concentrations 3 and 10 ng/L) of EE2 from fertilization to 80 days of age, followed by 82 days of remediation in clean water. RNA sequencing analysis revealed 249 and 16 genes to be differentially expressed after exposure to 1.2 and 1.6 ng/L, respectively; a larger inter-sample variation was noted in the latter. Expression of 11 genes were altered by both exposures and in the same direction. The coding sequences most affected could be categorized to the putative functions cell signalling, proteolysis, protein metabolic transport and lipid metabolic process. Several homeobox transcription factors involved in development and differentiation showed increased expression in response to EE2 and differential expression of genes related to cell death, differentiation and proliferation was observed. In addition, several genes related to steroid synthesis, testis development and function were differentially expressed. A number of genes associated with spermatogenesis in zebrafish and/or mouse were also found to be differentially expressed. Further, differences in non-coding sequences were observed, among them several differentially expressed miRNA that might contribute to testis gene regulation at post-transcriptional level. This study has generated insights of changes in gene expression that accompany fertility alterations in zebrafish males that persist after developmental exposure to environmental relevant concentrations of EE2 that persist followed by clean water to adulthood. Hopefully, this will generate hypotheses to test in search for mechanistic explanations.
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Affiliation(s)
- T Porseryd
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden.
| | - N Reyhanian Caspillo
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden
| | - K Volkova
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden
| | - L Elabbas
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden
| | - T Källman
- National Bioinformatics Infrastructure Sweden, Uppsala University, 75124 Uppsala, Sweden; Science for Life Laboratory and Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden
| | - P Dinnétz
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden
| | - P-E Olsson
- Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden
| | - I Porsch-Hällström
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden
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Liu YY, Hu XL, Bao YF, Yin DQ. Simultaneous determination of 29 pharmaceuticals in fish muscle and plasma by ultrasonic extraction followed by SPE-UHPLC-MS/MS. J Sep Sci 2018; 41:2139-2150. [DOI: 10.1002/jssc.201701360] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 01/27/2018] [Accepted: 01/28/2018] [Indexed: 12/30/2022]
Affiliation(s)
- You-yu Liu
- Key Laboratory of Yangtze River Water Environment; Ministry of Education; College of Environmental Science and Engineering; Tongji University; Shanghai P. R. China
| | - Xia-lin Hu
- Key Laboratory of Yangtze River Water Environment; Ministry of Education; College of Environmental Science and Engineering; Tongji University; Shanghai P. R. China
| | - Yi-fan Bao
- Key Laboratory of Yangtze River Water Environment; Ministry of Education; College of Environmental Science and Engineering; Tongji University; Shanghai P. R. China
| | - Da-qiang Yin
- Key Laboratory of Yangtze River Water Environment; Ministry of Education; College of Environmental Science and Engineering; Tongji University; Shanghai P. R. China
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10
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García-García M, Sánchez-Hernández M, García-Hernández MP, García-Ayala A, Chaves-Pozo E. Role of 5α-dihydrotestosterone in testicular development of gilthead seabream following finasteride administration. J Steroid Biochem Mol Biol 2017; 174:48-55. [PMID: 28739284 DOI: 10.1016/j.jsbmb.2017.07.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/17/2017] [Accepted: 07/19/2017] [Indexed: 02/04/2023]
Abstract
In teleosts, spermatogenesis is regulated by pituitary gonadotropins and sex steroids. 5α-dihydrotestosterone (DHT), derived from testosterone (T) through the action of 5α-reductase, has recently been suggested to play a physiologically important role in some fish species. In this study, gilthead seabream, Sparus aurata L., males received an implant of 1μgT/g body mass (bm) or vehicle alone and, 7days later, 1mg finasteride (FIN, an inhibitor of 5α-reductase)/kg bm or vehicle. Serum levels of T, 11-ketotestosterone (11KT), DHT and 17β-estradiol (E2), and the mRNA levels of the main enzymes involved in their synthesis, were analysed. T promoted a transient increase in the serum levels of T, 11KT and E2 but a decrease in those of DHT at day 15 following T injection, in accordance with the up-regulation of mRNA levels of the enzymes involved in T transformation to 11KT (coding genes: cyp11b1 and hsd11b) and the down-regulation of mRNA levels of the enzyme responsible for T transformation to DHT (coding gene: srd5a). Interestingly, a similar effect was observed when FIN was injected. However, when fish were injected with T and FIN successively (T+FIN), control levels were not recovered at the end of the experimental period (28days). DHT seems to regulate E2 serum levels via the down-regulation of mRNA levels of aromatase (coding gene: cyp19a1a), which is needed for the transformation of T into E2. The testis histology, together with the proliferative rates recorded upon T, FIN or T+FIN treatment, suggests that DHT is involved in the onset of the meiotic phase of spermatogenesis.
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Affiliation(s)
- M García-García
- Sección de Microscopía, Servicio de Apoyo a la Investigación Regional, Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia 30100, Spain
| | - M Sánchez-Hernández
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía, Puerto de Mazarrón, 30860, Spain
| | - M P García-Hernández
- Department of Cell Biology and Histology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, 30100, Spain
| | - A García-Ayala
- Department of Cell Biology and Histology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, 30100, Spain
| | - E Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía, Puerto de Mazarrón, 30860, Spain.
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11
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von Krogh K, Bjørndal GT, Nourizadeh-Lillabadi R, Hodne K, Ropstad E, Haug TM, Weltzien FA. Sex steroids differentially regulate fshb, lhb and gnrhr expression in Atlantic cod ( Gadus morhua). Reproduction 2017; 154:581-594. [PMID: 28780570 DOI: 10.1530/rep-17-0208] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 07/23/2017] [Accepted: 07/31/2017] [Indexed: 01/03/2023]
Abstract
Depending on the stage of gonad maturation, as well as other factors, gonadal steroids can exert either a positive or negative feedback at the brain and pituitary level. While this has been demonstrated in many teleost species, little is known about the nature of steroid feedback in Gadiform fish. Using an optimized in vitro model system of the Atlantic cod pituitary, the present study investigated the potential effects of two physiologically relevant doses of estradiol, testosterone (TS) or dihydrotestosterone (DHTS) on cell viability and gene expression of gonadotropin subunits (fshb/lhb) and two suggested reproduction-relevant gonadotropin-releasing hormone receptors (gnrhr1b/gnrhr2a) during three stages of sexual maturity. In general, all steroids stimulated cell viability in terms of metabolic activity and membrane integrity. Furthermore, all steroids affected fshb expression, with the effect depending on both the specific steroid, dose and maturity status. Conversely, only DHTS exposure affected lhb levels, and this occurred only during the spawning season. Using single-cell qPCR, co-transcription of gnrhr1b and gnrhr2a was confirmed to both fshb- and lhb- expressing gonadotropes, with gnrhr2a being the most prominently expressed isoform. While steroid exposure had no effect on gnrhr1b expression, all steroids affected gnrhr2a transcript levels in at least one maturity stage. These and previous results from our group point to Gnrhr2a as the main modulator of gonadotropin regulation in cod and that regulation of its gene expression level might function as a direct mechanism for steroid feedback at the pituitary level.
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Affiliation(s)
- Kristine von Krogh
- Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | | | | | - Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Erik Ropstad
- Department of Production Animal Clinical Sciences, Norwegian University of Life Science, Oslo, Norway
| | - Trude M Haug
- Department of Biosciences, University of Oslo, Oslo, Norway.,Department of Oral Biology, University of Oslo, Oslo, Norway
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway
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12
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Cleveland BM, Weber GM. Effects of steroid treatment on growth, nutrient partitioning, and expression of genes related to growth and nutrient metabolism in adult triploid rainbow trout (Oncorhynchus mykiss). Domest Anim Endocrinol 2016; 56:1-12. [PMID: 26905215 DOI: 10.1016/j.domaniend.2016.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 01/14/2016] [Accepted: 01/17/2016] [Indexed: 12/16/2022]
Abstract
The contribution of sex steroids to nutrient partitioning and energy balance during gonad development was studied in rainbow trout. Specifically, 19-mo old triploid (3N) female rainbow trout were fed treatment diets supplemented with estradiol-17β (E2), testosterone (T), or dihydrotestosterone at 30-mg steroid/kg diet for a 1-mo period. Growth performance, nutrient partitioning, and expression of genes central to growth and nutrient metabolism were compared with 3N and age-matched diploid (2N) female fish consuming a control diet not supplemented with steroids. Only 2 N fish exhibited active gonad development, with gonad weights increasing from 3.7% to 5.5% of body weight throughout the study, whereas gonad weights in 3N fish remained at 0.03%. Triploid fish consuming dihydrotestosterone exhibited faster specific growth rates than 3N-controls (P < 0.05). Consumption of E2 in 3N fish reduced fillet growth and caused lower fillet yield compared with all other treatment groups (P < 0.05). In contrast, viscera fat gain was not affected by steroid consumption (P > 0.05). Gene transcripts associated with physiological pathways were identified in maturing 2N and E2-treated 3N fish that differed in abundance from 3N-control fish (P < 0.05). In liver these mechanisms included the growth hormone/insulin-like growth factor (IGF) axis (igf1, igf2), IGF binding proteins (igfbp1b1, igfbp2b1, igfbp5b1, igfbp6b1), and genes associated with lipid binding and transport (fabp3, fabp4, lpl, cd36), fatty acid oxidation (cpt1a), and the pparg transcription factor. In muscle, these mechanisms included reductions in myogenic gene expression (fst, myog) and the proteolysis-related gene, cathepsin-L, suggesting an E2-induced reduction in the capacity for muscle growth. These findings suggest that increased E2 signaling in the sexually maturing female rainbow trout alters physiological pathways in liver, particularly those related to IGF signaling and lipid metabolism, to partition nutrients away from muscle growth toward support of maturation-related processes. In contrast, the mobilization of viscera lipid stores appear to be mediated less by E2 and more by energy demands associated with gonad development. These findings improve the understanding of how steroids regulate nutrient metabolism to meet the high energy demands associated with gonad development during sexual maturation.
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Affiliation(s)
- B M Cleveland
- National Center for Cool and Cold Water Aquaculture, USDA/ARS, Kearneysville, WV 25430, USA.
| | - G M Weber
- National Center for Cool and Cold Water Aquaculture, USDA/ARS, Kearneysville, WV 25430, USA
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13
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Collette TW, Skelton DM, Davis JM, Cavallin JE, Jensen KM, Kahl MD, Villeneuve DL, Ankley GT, Martinović-Weigelt D, Ekman DR. Metabolite profiles of repeatedly sampled urine from male fathead minnows (Pimephales promelas) contain unique lipid signatures following exposure to anti-androgens. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2016; 19:190-198. [PMID: 26810197 DOI: 10.1016/j.cbd.2016.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/10/2015] [Accepted: 01/03/2016] [Indexed: 11/16/2022]
Abstract
The purpose of this study was twofold. First, we sought to identify candidate markers of exposure to anti-androgens by analyzing endogenous metabolite profiles in the urine of male fathead minnows (mFHM, Pimephales promelas). Based on earlier work, we hypothesized that unidentified lipids in the urine of mFHM were selectively responsive to exposure to androgen receptor antagonists, which is otherwise difficult to confirm using established fish toxicity assays. A second goal was to evaluate the feasibility of non-lethally and repeatedly sampling urine from individual mFHMs over the time course of response to a chemical exposure. Accordingly, we exposed mFHM to the model anti-androgens vinclozolin or flutamide. Urine was collected from each fish at 48hour intervals over the course of a 14day exposure. Parallel experiments were conducted with mFHM exposed to bisphenol A or control water. The frequent handling/sampling regime did not cause apparent adverse effects on the fish. Endogenous metabolite profiling was conducted with gas chromatography-mass spectrometry (GC-MS), which exhibited lower variation for the urinary metabolome than was found in earlier work with nuclear magnetic resonance (NMR) spectroscopy. Specifically, for inter- and intra-individual variations, the median spectrum-wide relative standard deviation (RSD) was 32.6% and 33.3%, respectively, for GC-MS analysis of urine from unexposed mFHM. These results compared favorably with similar measurements of urine from other model species, including the Sprague Dawley rat. In addition, GC-MS allowed us to identify several lipids (e.g., certain saturated fatty acids) in mFHM urine as candidate markers of exposure to androgen receptor antagonists.
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Affiliation(s)
| | - David M Skelton
- U.S. EPA, National Exposure Research Laboratory, Athens, GA 30605, USA
| | - John M Davis
- U.S. EPA, National Exposure Research Laboratory, Athens, GA 30605, USA
| | - Jenna E Cavallin
- U.S. EPA, National Health and Environmental Effects Research Laboratory, Duluth, MN 55804, USA
| | - Kathleen M Jensen
- U.S. EPA, National Health and Environmental Effects Research Laboratory, Duluth, MN 55804, USA
| | - Michael D Kahl
- U.S. EPA, National Health and Environmental Effects Research Laboratory, Duluth, MN 55804, USA
| | - Daniel L Villeneuve
- U.S. EPA, National Health and Environmental Effects Research Laboratory, Duluth, MN 55804, USA
| | - Gerald T Ankley
- U.S. EPA, National Health and Environmental Effects Research Laboratory, Duluth, MN 55804, USA
| | | | - Drew R Ekman
- U.S. EPA, National Exposure Research Laboratory, Athens, GA 30605, USA
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14
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Ornostay A, Marr J, Loughery JR, Martyniuk CJ. Transcriptional networks associated with 5-alpha-dihydrotestosterone in the fathead minnow (Pimephales promelas) ovary. Gen Comp Endocrinol 2016; 225:23-32. [PMID: 26344943 DOI: 10.1016/j.ygcen.2015.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 09/02/2015] [Accepted: 09/02/2015] [Indexed: 11/17/2022]
Abstract
Androgens play a significant role in regulating oogenesis in teleost fishes. The androgen dihydrotestosterone (DHT) is a potent non-aromatizable androgen involved in sexual differentiation in mammals; however, its actions are not well understood in teleost fish. To better characterize the physiological role of DHT in the fathead minnow (FHM) ovary on a temporal scale, in vitro assays for 17β-estradiol (E2) production were conducted in parallel with microarray analysis. Ovarian explants were incubated at different concentrations of DHT (10(-6), 10(-7), and 10(-8)M DHT) in three separate experiments conducted at 6, 9, and 12h. DHT treatment resulted in a rapid and consistent increase in E2 production from the ovary at all three time points. Therefore, DHT may act to shift the balance of metabolites in the steroidogenic pathway within the ovary. Major biological themes affected by DHT in the ovary in one or more of the time points included those related to blood (e.g. vasodilation, blood vessel contraction, clotting), lipids (e.g. lipid storage, cholesterol metabolism, lipid degradation) and reproduction (e.g. hormone and steroid metabolism). Gene networks related to immune responses and calcium signaling were also affected by DHT, suggesting that this androgen may play a role in regulating these processes in the ovary. This study detected no change in mRNA levels of steroidogenic enzymes (cyp19a1, star, 11βhsd, 17βhsd, srd5a isoforms), suggesting that the observed increase in E2 production is likely more dependent on the pre-existing gene or protein complement in the ovary rather than the de novo expression of transcripts. This study increases knowledge regarding the roles of DHT and androgens in general in the teleost ovary and identifies molecular signaling pathways that may be associated with increased E2 production.
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Affiliation(s)
- Anna Ornostay
- Department of Biology and Canadian Rivers Institute, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - Joshua Marr
- Department of Biology and Canadian Rivers Institute, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - Jennifer R Loughery
- Department of Biology and Canadian Rivers Institute, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - Christopher J Martyniuk
- Department of Biology and Canadian Rivers Institute, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada; Department of Physiological Sciences and Center for Environmental and Human Toxicology, UF Genetics Institute, University of Florida, Gainesville, FL 32611, USA.
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15
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Bain PA, Papanicolaou A, Kumar A. Identification of Putative Nuclear Receptors and Steroidogenic Enzymes in Murray-Darling Rainbowfish (Melanotaenia fluviatilis) Using RNA-Seq and De Novo Transcriptome Assembly. PLoS One 2015; 10:e0142636. [PMID: 26599404 PMCID: PMC4658143 DOI: 10.1371/journal.pone.0142636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/23/2015] [Indexed: 11/18/2022] Open
Abstract
Murray-Darling rainbowfish (Melanotaenia fluviatilis [Castelnau, 1878]; Atheriniformes: Melanotaeniidae) is a small-bodied teleost currently under development in Australasia as a test species for aquatic toxicological studies. To date, efforts towards the development of molecular biomarkers of contaminant exposure have been hindered by the lack of available sequence data. To address this, we sequenced messenger RNA from brain, liver and gonads of mature male and female fish and generated a high-quality draft transcriptome using a de novo assembly approach. 149,742 clusters of putative transcripts were obtained, encompassing 43,841 non-redundant protein-coding regions. Deduced amino acid sequences were annotated by functional inference based on similarity with sequences from manually curated protein sequence databases. The draft assembly contained protein-coding regions homologous to 95.7% of the complete cohort of predicted proteins from the taxonomically related species, Oryzias latipes (Japanese medaka). The mean length of rainbowfish protein-coding sequences relative to their medaka homologues was 92.1%, indicating that despite the limited number of tissues sampled a large proportion of the total expected number of protein-coding genes was captured in the study. Because of our interest in the effects of environmental contaminants on endocrine pathways, we manually curated subsets of coding regions for putative nuclear receptors and steroidogenic enzymes in the rainbowfish transcriptome, revealing 61 candidate nuclear receptors encompassing all known subfamilies, and 41 putative steroidogenic enzymes representing all major steroidogenic enzymes occurring in teleosts. The transcriptome presented here will be a valuable resource for researchers interested in biomarker development, protein structure and function, and contaminant-response genomics in Murray-Darling rainbowfish.
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Affiliation(s)
- Peter A. Bain
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Land and Water, Urrbrae, South Australia, Australia
- * E-mail:
| | - Alexie Papanicolaou
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Land and Water, Black Mountain, Australian Capital Territory, Australia
| | - Anupama Kumar
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Land and Water, Urrbrae, South Australia, Australia
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16
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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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17
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Glinka CO, Frasca S, Provatas AA, Lama T, DeGuise S, Bosker T. The effects of model androgen 5α-dihydrotestosterone on mummichog (Fundulus heteroclitus) reproduction under different salinities. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 165:266-276. [PMID: 26141585 DOI: 10.1016/j.aquatox.2015.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 06/04/2023]
Abstract
Endocrine disrupting substances (EDSs) have the potential to disturb sensitive hormone pathways, particularly those involved in development and reproduction. Both fresh and estuarine water bodies receive inputs of EDSs from a variety of sources, including sewage effluent, industrial effluent and agricultural runoff. Based on current literature, freshwater species appear to respond to lower levels of EDSs than estuarine or marine species. Therefore, effects elicited by EDSs in freshwater teleosts may not be an accurate representation of how EDSs affect teleosts in estuarine and marine environments. To address this potential difference, a short-term reproductive bioassay was conducted under conditions of low and high salinity using mummichog (Fundulus heteroclitus), a euryhaline species that is native to the east coast of North America. The goals of this study were to determine the response of mummichog when exposed to an androgenic EDS and whether salinity affected the response. A model androgen, 5α-dihydrotestosterone (DHT), was selected for this experiment. Impacts on reproduction were evaluated at multiple biological levels, including physiological (sex steroid levels), organismal (gonad size and gonad morphology), and functional (egg production) endpoints. Under conditions of high salinity, egg production was significantly reduced at all exposure concentrations. Under conditions of low salinity, there were no significant differences based on DHT treatment; however, egg production in all treatment groups including the control were significantly reduced relative to the high salinity control group. Other reproductive endpoints, such as sex steroid production, showed stronger correlation to fecundity in females than males. This study demonstrates that mummichog fecundity is sensitive to androgenic endocrine disruption while also underscoring the importance of how changes in salinity, an environmental variable, can impact reproduction.
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Affiliation(s)
- Chelsea O Glinka
- Department of Natural Resources and the Environment, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT 06269, USA
| | - Salvatore Frasca
- Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT 06269, USA
| | - Anthony A Provatas
- Center for Environmental Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Tanya Lama
- Department of Natural Resources and the Environment, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT 06269, USA
| | - Sylvain DeGuise
- Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT 06269, USA
| | - Thijs Bosker
- Department of Natural Resources and the Environment, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT 06269, USA; Center for Environmental Science and Engineering, University of Connecticut, Storrs, CT 06269, USA.
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18
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Lee MR, Loux-Turner JR, Oliveira K. Evaluation of the 5α-reductase inhibitor finasteride on reproduction and gonadal development in medaka, Oryzias latipes. Gen Comp Endocrinol 2015; 216:64-76. [PMID: 25910435 DOI: 10.1016/j.ygcen.2015.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 04/11/2015] [Accepted: 04/11/2015] [Indexed: 11/19/2022]
Abstract
5-α reductase (5αR) inhibitors have an anti-androgenic effect in mammals because they inhibit the conversion of testosterone to the potent androgen, dihydrotestosterone. Finasteride is a type-2 5αR inhibitor that is used as a human pharmaceutical for the treatment of prostate cancer, benign prostate hyperplasia and male pattern baldness. This study evaluated the impacts of finasteride (50, 500 and 5000μg/L) on the development and reproduction of medaka (Oryzias latipes) exposed continuously over multiple generations (F0, F1 and F2). The exposure was initiated with reproductively mature fish (F0 generation) and continued until the hatching of the F2 generation. There were no significant effects on survival, fecundity or fertility in the F0 (50, 500, 5000μg/L) and F1 (50, 500μg/L) generations. The F1 generation exposed to 5000μg/L exhibited significant mortality. Histopathology of the gonads demonstrated that medaka and pre-clinical species respond similarly to finasteride exposure. Intersex condition and maldeveloped gonads were observed in F0 generation males exposed to 5000μg/L and F1 generation males exposed to 500μg/L. F1 generation males exposed to 500μg/L displayed reduced gonadosomatic index with an increased incidence of testicular degeneration. Males in both generations exhibited an increased incidence of Leydig cell hyperplasia at concentrations ⩾500μg/L. F0 generation females exposed to 5000μg/L exhibited increased gonadosomatic index. An increased prevalence of accelerated post-ovulatory follicle involution was observed in females at concentrations ⩾500μg/L in both generations. The gonadal changes induced by finasteride support the idea that 5-α reductase inhibition impacts androgen signaling in fish. Results from this study are discussed in the context of differential expression of the androgen receptor between species of fish.
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Affiliation(s)
- Michael R Lee
- University of Massachusetts Dartmouth, 238 Old Westport Road, North Dartmouth, MA 02747, USA; Smithers Viscient, 790 Main Street, Wareham, MA 02571, USA.
| | | | - Kenneth Oliveira
- University of Massachusetts Dartmouth, 238 Old Westport Road, North Dartmouth, MA 02747, USA
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19
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Valero Y, Sánchez-Hernández M, García-Alcázar A, García-Ayala A, Cuesta A, Chaves-Pozo E. Characterization of the annual regulation of reproductive and immune parameters on the testis of European sea bass. Cell Tissue Res 2015; 362:215-29. [PMID: 25896883 DOI: 10.1007/s00441-015-2172-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 03/18/2015] [Indexed: 11/30/2022]
Abstract
The European sea bass, Dicentrarchus labrax L., is a seasonal gonochoristic species, the males of which are generally mature during their second year of life. It has been demonstrated that cytokines and immune cells play a key role in the testicular development. This reproductive-immune interaction might be very important in the sea bass since several pathogens are able to colonise the gonad and persist in this tissue, altering further reproductive functions and spreading disease. This study aims to investigate the reproductive cycle of 1-year European sea bass males by analysing cell proliferation and apoptosis and the expression profile of some reproductive and immune-related genes in the testis, as well as the serum sex steroid levels. Our data demonstrate that, in 1-year-old European sea bass males, the testis undergoes the spermatogenesis process and that the reproductive and immune parameters analysed varied during the reproductive cycle. In the testis, the highest proliferative rates were recorded at the spermatogenesis stage, while the highest apoptotic rates were recorded at the spawning stage. We have also analysed, for the first time in European sea bass males, the serum levels of 17β-estradiol (E2) and dihydrotestosterone and the gene expression profile of the enzymes implied in their production, determining that at least E2 might be involved in the regulation of the reproductive cycle. Some immune relevant genes, including cytokines, lymphocyte receptors, and anti-viral and anti-bacterial molecules were detected in the testis of naïve European sea bass specimens, and their expression profile was related to the stages of the reproductive cycle, suggesting an important role for the defence of the reproductive tissues.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Miriam Sánchez-Hernández
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alicia García-Alcázar
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alfonsa García-Ayala
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain.
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Rutherford R, Lister A, Hewitt LM, MacLatchy D. Effects of model aromatizable (17α-methyltestosterone) and non-aromatizable (5α-dihydrotestosterone) androgens on the adult mummichog (Fundulus heteroclitus) in a short-term reproductive endocrine bioassay. Comp Biochem Physiol C Toxicol Pharmacol 2015; 170:8-18. [PMID: 25634815 DOI: 10.1016/j.cbpc.2015.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 01/14/2015] [Accepted: 01/19/2015] [Indexed: 10/24/2022]
Abstract
Androgens originating from pulp mill processing, sewage treatment facilities and agricultural activities have the potential for discharge into aquatic receiving environments. To assess androgen effects on reproductive endocrine status in fish in estuarine environments, male and female adult northern mummichog (Fundulus heteroclitus macrolepidotus) were exposed to an aromatizable androgen (17α-methyltestosterone; MT) and a non-aromatizable androgen (5α-dihydrotestosterone; DHT) in a short-term reproductive endocrine bioassay. Fish were nominally exposed to 10 μg/L or 100 μg/L DHT, or 0.1 μg/L or 1 μg/L MT for 14 days during gonadal recrudescence. Actual concentrations of androgens, as measured by enzyme immunoassay (EIA), were 10-49% of nominal MT 0.1, 3-6% of nominal MT 1, 5-10% of nominal DHT 10 and 3-25% of nominal DHT 100. Female mummichog were impacted to a greater degree by androgen exposure, with increased plasma testosterone (T) at 100 μg/L DHT, depressed plasma 17β-estradiol (E2) at both DHT concentrations and at 1 μg/L MT, as well as depressed in vitro E2 at both MT concentrations and 100 μg/L DHT. Males had depressed plasma T in the 10 μg/L DHT treatment and depressed in vitro 11-ketotestosterone production for both MT concentrations and 10 μg/L DHT. Ovarian aromatase gene expression was induced in females exposed to 1 μg/L MT. DHT at 100 μg/L increased hepatic vitellogenin-1 (VTG1) expression in males and depressed VTG1 expression in females. The range of responses between sexes and among species provides evidence for modes of actions and potential impacts of androgens in aquatic receiving environments.
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Affiliation(s)
- Robert Rutherford
- Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON N2L 3C5, Canada.
| | - Andrea Lister
- Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON N2L 3C5, Canada
| | - L Mark Hewitt
- National Water Research Institute, Environment Canada, Burlington, ON L7R 4A6, Canada
| | - Deborah MacLatchy
- Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON N2L 3C5, Canada
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Bain PA, Ogino Y, Miyagawa S, Iguchi T, Kumar A. Differential ligand selectivity of androgen receptors α and β from Murray-Darling rainbowfish (Melanotaenia fluviatilis). Gen Comp Endocrinol 2015; 212:84-91. [PMID: 25644213 DOI: 10.1016/j.ygcen.2015.01.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/20/2015] [Accepted: 01/24/2015] [Indexed: 11/16/2022]
Abstract
Androgen receptors (ARs) mediate the physiological effects of androgens in vertebrates. In fishes, AR-mediated pathways can be modulated by aquatic contaminants, resulting in the masculinisation of female fish or diminished secondary sex characteristics in males. The Murray-Darling rainbowfish (Melanotaenia fluviatilis) is a small-bodied freshwater teleost used in Australia as a test species for environmental toxicology research. We determined concentration-response profiles for selected agonists and antagonists of rainbowfish ARα and ARβ using transient transactivation assays. For both ARα and ARβ, the order of potency of natural agonists was 11-ketotestosterone (11-KT)>5α-dihydrotestosterone>testosterone>androstenedione. Methyltestosterone was a highly potent agonist of both receptors relative to 11-KT. The relative potency of the veterinary growth-promoting androgen, 17β-trenbolone, varied by more than a factor of 5 between ARα and ARβ. The non-steroidal anti-androgen bicalutamide exhibited high inhibitory potency relative to the structurally related model anti-androgen, flutamide. The inhibitory potency of the agricultural fungicide, vinclozolin, was approximately 1.7-fold relative to flutamide for ARα, but over 20-fold in the case of ARβ. Fluorescent protein tagging of ARs showed that the rainbowfish ARα subtype is constitutively localised to the nucleus, while ARβ is cytoplasmic in the absence of ligand, an observation which agrees with the reported subcellular localisation of AR subtypes from other teleost species. Collectively, these data suggest that M. fluviatilis ARα and ARβ respond differently to environmental AR modulators and that in vivo sensitivity to contaminants may depend on the tissue distribution of the AR subtypes at the time of exposure.
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Affiliation(s)
- Peter A Bain
- Land and Water Flagship, Commonwealth Scientific and Industrial Research Organisation, PMB 2, Glen Osmond, South Australia 5064, Australia.
| | - Yukiko Ogino
- Division of Molecular Environmental Endocrinology, National Institute for Basic Biology, Nishigonaka-38 Myodaijicho, Okazaki, Aichi Prefecture 444-0867, Japan
| | - Shinichi Miyagawa
- Division of Molecular Environmental Endocrinology, National Institute for Basic Biology, Nishigonaka-38 Myodaijicho, Okazaki, Aichi Prefecture 444-0867, Japan
| | - Taisen Iguchi
- Division of Molecular Environmental Endocrinology, National Institute for Basic Biology, Nishigonaka-38 Myodaijicho, Okazaki, Aichi Prefecture 444-0867, Japan
| | - Anupama Kumar
- Land and Water Flagship, Commonwealth Scientific and Industrial Research Organisation, PMB 2, Glen Osmond, South Australia 5064, Australia
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22
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González A, Fernandino JI, Somoza GM. Effects of 5α-dihydrotestosterone on expression of genes related to steroidogenesis and spermatogenesis during the sex determination and differentiation periods of the pejerrey, Odontesthes bonariensis. Comp Biochem Physiol A Mol Integr Physiol 2014; 182:1-7. [PMID: 25499236 DOI: 10.1016/j.cbpa.2014.12.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 11/28/2014] [Accepted: 12/01/2014] [Indexed: 10/24/2022]
Abstract
Sex steroid hormones are important players in the control of sex differentiation by regulating gonadal development in teleosts. Although estrogens are clearly associated with the ovarian differentiation in teleosts, the effects of androgens on early gonadal development are still a matter of debate. Traditionally, 11-ketotestosterone (11-KT) is considered the major androgen in fish; however, 5α-dihydrotestosterone (5α-DHT), the most potent androgen in tetrapods, was recently found in fish testis and plasma, but its physiological role is still unknown. In this context, the expression of genes associated with steroidogenesis and spermatogenesis, body growth and sex differentiation were assessed in Odontesthes bonariensis larvae fed with food supplemented with two doses of 5α-DHT (0.1 and 10μg/g of food) from hatching to 6weeks of age. At the lowest dose, 5α-DHT treated larvae showed an estrogenic gene expression pattern, with low hsd11b2 and high cyp19a1a and er2 expression levels with no differences in sex ratio. At the highest dose, 5α-DHT produced a male-shifted sex ratio and the larvae exhibited a gene expression profile characteristic of an advancement of spermatogenesis, with inhibition of amh and stimulation of ndrg3. No differences were observed in somatic growth. These results suggest that in this species, 5α-DHT could have a role on sex differentiation and its effects can differ according to the dose.
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Affiliation(s)
- Anelisa González
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH, CONICET-UNSAM), Av. Intendente Marino Km. 8.2 (B7130IWA), Chascomús, Buenos Aires, Argentina
| | - Juan I Fernandino
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH, CONICET-UNSAM), Av. Intendente Marino Km. 8.2 (B7130IWA), Chascomús, Buenos Aires, Argentina
| | - Gustavo M Somoza
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH, CONICET-UNSAM), Av. Intendente Marino Km. 8.2 (B7130IWA), Chascomús, Buenos Aires, Argentina.
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23
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Martyniuk CJ, Bissegger S, Langlois VS. Reprint of "Current perspectives on the androgen 5 alpha-dihydrotestosterone (DHT) and 5 alpha-reductases in teleost fishes and amphibians". Gen Comp Endocrinol 2014; 203:10-20. [PMID: 24954687 DOI: 10.1016/j.ygcen.2014.06.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The androgen 5 alpha-dihydrotestosterone (DHT) is a steroidogenic metabolite that has received little attention in non-mammalian species. DHT is produced by the reduction of the double-bond of testosterone by a group of enzymes called 5 alpha-reductases of which there can be multiple isoforms (i.e., srd5a1, srd5a2, and srd5a3). Data from amphibians suggest that the expression of the srd5a genes occurs in early development, and continues until adulthood; however insufficient data exist in fish species, where DHT is thought to be relatively biologically inactive. Here, we demonstrate that fathead minnow (FHM; Pimephales promelas) developing embryos and adults express srd5a enzyme isoforms. During FHM embryogenesis, both srd5a1 and srd5a3 mRNA levels were significantly correlated in expression levels while srd5a2 showed a more unique pattern of expression. In adult FHMs, males had significantly higher levels of srd5a2 in the liver and gonad compared to females. In the male and female liver, transcript levels for srd5a2 were more abundant compared to srd5a1 and srd5a3, suggesting a prominent role for srd5a2 in this tissue. Interestingly, the ovary expressed higher mRNA levels of srd5a3 than the testis. Thus, data suggest that srd5a isoforms can show sexually dimorphic expression patterns in fish. We also conducted a literature review of the biological effects observed in embryonic and adult fish and amphibians after treatments with DHT and DHT-related compounds. Treatments with DHT in teleost fishes and amphibians have resulted in unexpected biological responses that are characteristic of both androgens and anti-androgens. For example, in fish DHT can induce vitellogenin in vitro from male and female hepatocytes and can increase 17β-estradiol production from the teleost ovary. We propose, that to generate further understanding of the roles of DHT in non-mammals, studies are needed that (1) address how DHT is synthesized within tissues of fish and amphibians; (2) examine the full range of biological responses to endogenous DHT, and its interactions with other signaling pathways; and (3) investigate how DHT production varies with reproductive stage. Lastly, we suggest that the Srd5a enzymes can be targets of endocrine disruptors in fish and frogs, which may result in disruptions in the estrogen:androgen balance in aquatic organisms.
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Affiliation(s)
| | - Sonja Bissegger
- Chemistry and Chemical Engineering Department, Royal Military College of Canada, Kingston, ON K7K 7B4, Canada.
| | - Valérie S Langlois
- Chemistry and Chemical Engineering Department, Royal Military College of Canada, Kingston, ON K7K 7B4, Canada.
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24
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Feswick A, Ings JS, Doyle MA, Bosker T, Munkittrick KR, Martyniuk CJ. Transcriptomics profiling and steroid production in mummichog (Fundulus heteroclitus) testes after treatment with 5α-dihydrotestosterone. Gen Comp Endocrinol 2014; 203:106-19. [PMID: 24447443 DOI: 10.1016/j.ygcen.2014.01.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 12/20/2013] [Accepted: 01/08/2014] [Indexed: 01/08/2023]
Abstract
5α-Dihydrotestosterone (DHT) is a potent androgen in mammals with multiple roles; however the physiological actions of DHT in male fishes are not well known. To address this knowledge gap, male mummichog (Fundulus heteroclitus) were continuously exposed to 0, 5, and 50 μg/L DHT for 21 days. Following exposure, testes were separated for histology, ex vivo incubation to measure steroidogenic capacity, and gene expression analyses (real-time PCR and microarray). DHT significantly decreased ex vivo 11-ketotestosterone (11KT) production in males exposed to 50 μg/L DHT but not 5 μg/L DHT, and DHT exposure did not affect ex vivo testosterone production. Histological examination revealed that the amount of interlobular and connective tissue present in the testes was increased in the 50 μg/L DHT treatment. Despite reductions in the production of 11KT, DHT did not affect the expression of targeted genes in the steroidogenic pathway such as steroidogenic acute regulatory protein (star), P450 side chain cleavage (cyp11a1) and 11β-hydroxysteroid dehydrogenase (hsd11b3). Microarray analysis in the testes of individuals from control and 50 μg/L DHT revealed that males exposed to 50 μg/L DHT showed regulated transcriptional sub-networks that were related to immunity, regulation of blood flow, lipids and xenobiotic clearance, suggesting that DHT may be involved in the physiological regulation of these processes in the fish testes. A second objective of this study was to determine the feasibility of measuring mRNA levels in tissues used for ex vivo steroid production by comparing RNA integrity and transcript levels in testes of both immediately flash frozen tissue and incubated tissue. There was no significant difference in RNA quality between the two time points, indicating RNA integrity can remain intact for at least 18 h in ex vivo assays, thereby providing a viable option for researchers assessing multi-level biological reproductive endpoints when limited tissue is available. While the gene expression levels of actb, efla, rps12, rps18, star, and hsd11b3 remained unchanged, esr2a (esrba), esr2b (esrbb) and cyp11a1 were significantly lower in incubated tissue compared to flash frozen tissue. Therefore caution must be used as the steady-state levels of select genes may change over time. This study improves our understanding of DHT action in the teleostean testis and generates new hypotheses regarding cell processes that are regulated by this underexplored and potent androgen.
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Affiliation(s)
- A Feswick
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - J S Ings
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - M A Doyle
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - T Bosker
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - K R Munkittrick
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
| | - C J Martyniuk
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada.
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25
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Martyniuk CJ, Bissegger S, Langlois VS. Current perspectives on the androgen 5 alpha-dihydrotestosterone (DHT) and 5 alpha-reductases in teleost fishes and amphibians. Gen Comp Endocrinol 2013; 194:264-74. [PMID: 24095809 DOI: 10.1016/j.ygcen.2013.09.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/23/2013] [Accepted: 09/26/2013] [Indexed: 11/29/2022]
Abstract
The androgen 5 alpha-dihydrotestosterone (DHT) is a steroidogenic metabolite that has received little attention in non-mammalian species. DHT is produced by the reduction of the double-bond of testosterone by a group of enzymes called 5 alpha-reductases of which there can be multiple isoforms (i.e., srd5a1, srd5a2, and srd5a3). Data from amphibians suggest that the expression of the srd5a genes occurs in early development, and continues until adulthood; however insufficient data exist in fish species, where DHT is thought to be relatively biologically inactive. Here, we demonstrate that fathead minnow (FHM; Pimephales promelas) developing embryos and adults express srd5a enzyme isoforms. During FHM embryogenesis, both srd5a1 and srd5a3 mRNA levels were significantly correlated in expression levels while srd5a2 showed a more unique pattern of expression. In adult FHMs, males had significantly higher levels of srd5a2 in the liver and gonad compared to females. In the male and female liver, transcript levels for srd5a2 were more abundant compared to srd5a1 and srd5a3, suggesting a prominent role for srd5a2 in this tissue. Interestingly, the ovary expressed higher mRNA levels of srd5a3 than the testis. Thus, data suggest that srd5a isoforms can show sexually dimorphic expression patterns in fish. We also conducted a literature review of the biological effects observed in embryonic and adult fish and amphibians after treatments with DHT and DHT-related compounds. Treatments with DHT in teleost fishes and amphibians have resulted in unexpected biological responses that are characteristic of both androgens and anti-androgens. For example, in fish DHT can induce vitellogenin in vitro from male and female hepatocytes and can increase 17β-estradiol production from the teleost ovary. We propose, that to generate further understanding of the roles of DHT in non-mammals, studies are needed that (1) address how DHT is synthesized within tissues of fish and amphibians; (2) examine the full range of biological responses to endogenous DHT, and its interactions with other signaling pathways; and (3) investigate how DHT production varies with reproductive stage. Lastly, we suggest that the Srd5a enzymes can be targets of endocrine disruptors in fish and frogs, which may result in disruptions in the estrogen:androgen balance in aquatic organisms.
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26
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Rand-Weaver M, Margiotta-Casaluci L, Patel A, Panter GH, Owen SF, Sumpter JP. The read-across hypothesis and environmental risk assessment of pharmaceuticals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:11384-95. [PMID: 24006913 PMCID: PMC3864244 DOI: 10.1021/es402065a] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 09/04/2013] [Accepted: 09/05/2013] [Indexed: 05/18/2023]
Abstract
Pharmaceuticals in the environment have received increased attention over the past decade, as they are ubiquitous in rivers and waterways. Concentrations are in sub-ng to low μg/L, well below acute toxic levels, but there are uncertainties regarding the effects of chronic exposures and there is a need to prioritise which pharmaceuticals may be of concern. The read-across hypothesis stipulates that a drug will have an effect in non-target organisms only if the molecular targets such as receptors and enzymes have been conserved, resulting in a (specific) pharmacological effect only if plasma concentrations are similar to human therapeutic concentrations. If this holds true for different classes of pharmaceuticals, it should be possible to predict the potential environmental impact from information obtained during the drug development process. This paper critically reviews the evidence for read-across, and finds that few studies include plasma concentrations and mode of action based effects. Thus, despite a large number of apparently relevant papers and a general acceptance of the hypothesis, there is an absence of documented evidence. There is a need for large-scale studies to generate robust data for testing the read-across hypothesis and developing predictive models, the only feasible approach to protecting the environment.
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Affiliation(s)
- Mariann Rand-Weaver
- Biosciences, School
of Health Sciences and Social Care, Brunel University, Uxbridge, Middlesex, UB8 3PH, United Kingdom
- (M.R.-W.) Phone: +44(0)1895
266297; fax: +44(0)1895 273545; e-mail:
| | | | - Alpa Patel
- Biosciences, School
of Health Sciences and Social Care, Brunel University, Uxbridge, Middlesex, UB8 3PH, United Kingdom
- Institute
for the Environment, Brunel University, Uxbridge, Middlesex, UB8 3PH, United Kingdom
| | - Grace H. Panter
- AstraZeneca, Brixham Environmental Laboratory, Freshwater
Quarry, Brixham, Devon, TQ5 8BA, United Kingdom
| | - Stewart F. Owen
- AstraZeneca, Brixham Environmental Laboratory, Freshwater
Quarry, Brixham, Devon, TQ5 8BA, United Kingdom
| | - John P. Sumpter
- Institute
for the Environment, Brunel University, Uxbridge, Middlesex, UB8 3PH, United Kingdom
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Balaguer P, Boussioux AM, Demirpence E, Nicolas JC. Reporter cell lines are useful tools for monitoring biological activity of nuclear receptor ligands. LUMINESCENCE 2001; 163:97-101. [PMID: 11312541 DOI: 10.1016/j.aquatox.2015.03.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/26/2015] [Accepted: 03/29/2015] [Indexed: 05/15/2023]
Abstract
To characterize the specificity of synthetic compounds for nuclear receptors, we established stable cell lines expressing the luciferase gene and different wild-type or chimaeric receptors. MCF-7 cells, which express the oestrogen receptor alpha (ER alpha), and HeLa cells, which do not express the oestrogen receptor, were transfected with a plasmid containing the luciferase gene downstream from a minimum promoter (beta-globin) and an oestrogen-responsive element, generating the MELN and the HELN cell lines, respectively. MELN cells enabled the detection of compounds that bind to the ER alpha or interfere with its pathway. HELN cells were used to establish stable transfectants expressing different nuclear receptors containing the DNA-binding domain of the oestrogen receptors. We thus established ER alpha or ER beta reporter cell lines by transfecting ER alpha or ER beta expression plasmids, and also retinoic acid receptor alpha, beta or gamma reporter cell lines by transfecting the chimaeric RAR gene, in which the DNA-binding domain was replaced by the ER alpha DNA-binding domain.
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Affiliation(s)
- P Balaguer
- INSERM U439, 70 Rue de Navacelles, 34090 Montpellier, France.
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