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Su M, Zhong Y, Chen Y, Xiang J, Ye Z, Liao S, Ye S, Zhang J. Assessment of environmental exposure to betamethasone on the reproductive function of female Japanese medaka (Oryzias latipes). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 281:116651. [PMID: 38959790 DOI: 10.1016/j.ecoenv.2024.116651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/24/2024] [Accepted: 06/26/2024] [Indexed: 07/05/2024]
Abstract
Betamethasone has been extensively used in medicine in recent years and poses potential hazards to aquatic organisms. This study investigated the reproductive toxic effects of betamethasone exposure in fish, employing female Japanese medaka (Oryzias latipes) as a model. Betamethasone exposure at environmentally relevant concentrations (0, 20, 200, and 2000 ng/L) for a period of 15 weeks resulted in its high accumulation in the ovary, leading to abnormal oogenesis in female Japanese medaka. The production of gonadotropins (LH and FSH) in the pituitary gland was inhibited, and sex steroid biosynthesis in the ovary was significantly influenced at the transcriptional level. The imbalance of androgens and estrogens resulted in a decrease in the E2/T ratio and hepatic VTG synthesis, and the suppression of estrogen receptor signaling was also induced. Furthermore, betamethasone exposure delayed spawning and reduced fertility in the F0 generation, and had detrimental effects on the fertilization rate and hatchability of the F1 generation. Our results showed that environmental betamethasone had the potential to adversely affect female fertility and steroid hormone dynamics in fish.
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Affiliation(s)
- Maoliang Su
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Youling Zhong
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Yuru Chen
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Jiazhi Xiang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Zhiyin Ye
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Shujia Liao
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Shiyang Ye
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Junbin Zhang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China.
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2
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Royan MR, Hodne K, Nourizadeh-Lillabadi R, Weltzien FA, Henkel C, Fontaine R. Day length regulates gonadotrope proliferation and reproduction via an intra-pituitary pathway in the model vertebrate Oryzias latipes. Commun Biol 2024; 7:388. [PMID: 38553567 PMCID: PMC10980775 DOI: 10.1038/s42003-024-06059-y] [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: 06/22/2023] [Accepted: 03/16/2024] [Indexed: 04/01/2024] Open
Abstract
In seasonally breeding mammals and birds, the production of the hormones that regulate reproduction (gonadotropins) is controlled by a complex pituitary-brain-pituitary pathway. Indeed, the pituitary thyroid-stimulating hormone (TSH) regulates gonadotropin expression in pituitary gonadotropes, via dio2-expressing tanycytes, hypothalamic Kisspeptin, RFamide-related peptide, and gonadotropin-releasing hormone neurons. However, in fish, how seasonal environmental signals influence gonadotropins remains unclear. In addition, the seasonal regulation of gonadotrope (gonadotropin-producing cell) proliferation in the pituitary is, to the best of our knowledge, not elucidated in any vertebrate group. Here, we show that in the vertebrate model Japanese medaka (Oryzias latipes), a long day seasonally breeding fish, photoperiod (daylength) not only regulates hormone production by the gonadotropes but also their proliferation. We also reveal an intra-pituitary pathway that regulates gonadotrope cell number and hormone production. In this pathway, Tsh regulates gonadotropes via folliculostellate cells within the pituitary. This study suggests the existence of an alternative regulatory mechanism of seasonal gonadotropin production in fish.
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Affiliation(s)
- Muhammad Rahmad Royan
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Kjetil Hodne
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Rasoul Nourizadeh-Lillabadi
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Finn-Arne Weltzien
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Christiaan Henkel
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Romain Fontaine
- Department of Preclinical Science and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
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3
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Closs LE, Royan MR, Sayyari A, Mayer I, Weltzien FA, Baker DM, Fontaine R. Artificial light at night disrupts male dominance relationships and reproductive success in a model fish species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:166406. [PMID: 37597540 DOI: 10.1016/j.scitotenv.2023.166406] [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: 04/20/2023] [Revised: 08/04/2023] [Accepted: 08/16/2023] [Indexed: 08/21/2023]
Abstract
Environmental light is perceived and anticipated by organisms to synchronize their biological cycles. Therefore, artificial light at night (ALAN) disrupts both diurnal and seasonal biological rhythms. Reproduction is a complex physiological process involving integration of environmental signals by the brain, and release of endocrine signals by the pituitary that regulate gametogenesis and spawning. In addition, males from many species form a dominance hierarchy that, through a combination of aggressive and protective behavior, influences their reproductive success. In this study, we investigated the effect of ALAN and continuous daylight on the behavior and fitness of male fish within a dominance hierarchy using a model fish, the Japanese medaka. In normal light/dark cycles, male medaka establish a hierarchy with the dominant males being more aggressive and remaining closer to the female thus limiting the access of subordinate males to females during spawning. However, determination of the paternity of the progeny revealed that even though subordinate males spend less time with the females, they are, in normal light conditions, equally successful at producing progeny due to an efficient sneaking behavior. Continuous daylight completely inhibited the establishment of male hierarchy, whereas ALAN did not affect it. Nonetheless, when exposed to ALAN, subordinate males fertilize far fewer eggs. Furthermore, we found that when exposed to ALAN, subordinate males produced lower quality sperm than dominant males. Surprisingly, we found no differences in circulating sex steroid levels, pituitary gonadotropin levels, or gonadosomatic index between dominant and subordinate males, neither in control nor ALAN condition. This study is the first to report an effect of ALAN on sperm quality leading to a modification of male fertilization success in any vertebrate. While this work was performed in a model fish species, our results suggest that in urban areas ALAN may impact the genetic diversity of species displaying dominance behavior.
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Affiliation(s)
- Lauren E Closs
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
| | - Muhammad Rahmad Royan
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
| | - Amin Sayyari
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
| | - Ian Mayer
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Finn-Arne Weltzien
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
| | - Dianne M Baker
- Department of Biological Sciences, University of Mary Washington, Fredericksburg, VA, United States.
| | - Romain Fontaine
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway.
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4
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Horie Y, Uaciquete D. Influence of phthalate and non-phthalate plasticizers on reproductive endocrine system-related gene expression profiles in Japanese medaka ( Oryzias latipes). JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2023; 58:954-962. [PMID: 37897219 DOI: 10.1080/10934529.2023.2273690] [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: 08/01/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023]
Abstract
Plasticizers containing phthalates have the potential to alter endocrine function in vertebrates. While non-phthalate plasticizers were previously considered to be environmentally friendly and safe, our research team discovered that bis-(2-ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC) disrupt thyroid hormones in Japanese medaka (Oryzias latipes). We assessed reproductive- and estrogen-responsive gene expression patterns in Japanese medaka to determine whether the phthalate plasticizers bis-(2-ethylhexyl) phthalate (DEHP, positive control) and the non-phthalate plasticizers DEHA and ATBC disrupt endocrine signaling. The results showed that the levels of choriogenin H (chgH) and vitellogenin (vtg) genes increased after exposure to DEHP and ATBC, suggesting that these plasticizers may have estrogenic activity. Exposure to DEHP and DEHA resulted in the upregulation of kisspeptin (kiss), gonadotropin-releasing hormone (gnrh), and follicle-stimulating hormone beta (fshβ) genes, suggesting that these plasticizers may interfere with reproductive function. To the best of our knowledge, this is the first study to demonstrate that the non-phthalate plasticizers DEHA and ATBC can disrupt reproduction-related hormonal activity in fish.
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Affiliation(s)
- Yoshifumi Horie
- Research Center for Inland Seas (KURCIS), Kobe University, Kobe, Japan
| | - Dorcas Uaciquete
- Research Center for Inland Seas (KURCIS), Kobe University, Kobe, Japan
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Su M, Zhong Y, Xiang J, Chen Y, Liu N, Zhang J. Reproductive endocrine disruption and gonadal intersex induction in male Japanese medaka chronically exposed to betamethasone at environmentally relevant levels. JOURNAL OF HAZARDOUS MATERIALS 2023; 455:131493. [PMID: 37156043 DOI: 10.1016/j.jhazmat.2023.131493] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 04/06/2023] [Accepted: 04/23/2023] [Indexed: 05/10/2023]
Abstract
The broad utilization of betamethasone in medical treatments may pose a significant ecotoxicological risk to aquatic organisms, yet its potential reproductive toxicity remains unclear. The present study examined the impacts of environmental exposure on male reproduction using Japanese medaka (Oryzias latipes). After 110 days of betamethasone exposure at environmentally relevant concentrations (0, 20 and 200 ng/L), LH/FSH synthesis and release in the pituitary was inhibited, and the production of sex hormones and their signaling pathways in the gonads of male medaka were greatly influenced. This synthetic glucocorticoid restrained testosterone (T) synthesis and gave rise to a significant increase in E2/T and E2/11-KT ratios. Furthermore, chronic betamethasone exposure (20 and 200 ng/L) led to the suppression of androgen receptor (AR) signaling and enhancement of estrogen receptors (ERs) signaling. An increase in hepatic vitellogenin contents was also detected, and testicular oocytes were observed in both 20 and 200 ng/L betamethasone-treated groups. It showed that 20 and 200 ng/L betamethasone could induce male feminization and even intersex, triggering abnormal spermatogenesis in medaka males. With its adverse effects on male fertility, betamethasone could potentially influence the fishery productivity and population dynamics in aquatic ecosystems.
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Affiliation(s)
- Maoliang Su
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Youling Zhong
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Jiazhi Xiang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Yuru Chen
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Nanxi Liu
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Junbin Zhang
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China.
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Horie Y, Nomura M, Ramaswamy BR, Harino H, Yap CK, Okamura H. Effects of non-phthalate plasticizer bis(2-ethylhexyl) sebacate (DEHS) on the endocrine system in Japanese medaka (Oryzias latipes). Comp Biochem Physiol C Toxicol Pharmacol 2023; 264:109531. [PMID: 36470400 DOI: 10.1016/j.cbpc.2022.109531] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/26/2022] [Accepted: 11/30/2022] [Indexed: 12/07/2022]
Abstract
Water pollution due to plasticizers is one of the most severe environmental problems worldwide. Phthalate plasticizers can act as endocrine disruptors in vertebrates. In this study, we investigated whether the non-phthalate bis(2-ethylhexyl) sebacate (DEHS) plasticizer can act as an endocrine disruptor by evaluating changes in the expression levels of thyroid hormone-related, reproduction-related, and estrogen-responsive genes of Japanese medaka (Oryzias latipes) exposed to the plasticizer. Following the exposure, the gene expression levels of thyroid-stimulating hormone subunit beta (tshβ), deiodinase 1 (dio1), and thyroid hormone receptor alpha (trα) did not change. Meanwhile, DEHS suppressed dio2 expression, did not induce swim bladder inflation, and eventually reduced the swimming performance of Japanese medaka. These findings indicate that DEHS can potentially disrupt the thyroid hormone-related gene expression and metabolism of these fish. However, exposure to DEHS did not induce changes in the gene expression levels of kisspeptin 1 (kiss1), gonadotropin-releasing hormone (gnrh), follicle-stimulating hormone beta (fshβ), luteinizing hormone beta (lhβ), choriogenin H (chgH), and vitellogenin (vtg) in a dose-dependent manner. This is the first report providing evidence that DEHS can disrupt thyroid hormone-related metabolism in fish.
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Affiliation(s)
- Yoshifumi Horie
- Research Center for Inland Seas (KURCIS), Kobe University, Fukaeminami-machi, Higashinada-ku, Kobe 658-0022, Japan.
| | - Miho Nomura
- Graduate School of Maritime Science, Kobe University, Fukaeminami-machi, Higashinada-ku, Kobe 658-0022, Japan
| | - Babu Rajendran Ramaswamy
- Research Center for Inland Seas (KURCIS), Kobe University, Fukaeminami-machi, Higashinada-ku, Kobe 658-0022, Japan; Department of Environmental Biotechnology, School of Environmental Sciences, Bharathidasan University, Tiruchirappalli 620024, India
| | - Hiroya Harino
- School of Human Sciences, Kobe College, 4-1 Okadayama, Nishinomiya, Hyogo, Iwate 662-8505, Japan
| | - Chee Kong Yap
- Department of Biology, Faculty of Science, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Hideo Okamura
- Research Center for Inland Seas (KURCIS), Kobe University, Fukaeminami-machi, Higashinada-ku, Kobe 658-0022, Japan
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7
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Ager-Wick E, Maugars G, von Krogh K, Fontaine R, Weltzien FA, Henkel C. An RNA-seq time series of the medaka pituitary gland during sexual maturation. Sci Data 2023; 10:62. [PMID: 36720883 PMCID: PMC9889309 DOI: 10.1038/s41597-023-01967-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 01/12/2023] [Indexed: 02/02/2023] Open
Abstract
Directing both organismal homeostasis and physiological adaptation, the pituitary is a key endocrine gland in all vertebrates. One of its major tasks is to coordinate sexual maturation through the production and release of hormones stimulating gonad development. In order to study its developmental dynamics in the model fish medaka (Oryzias latipes), we sampled both the pituitary and the ovaries of 68 female fish. Of these, 55 spanned the entire course of sexual maturation from prepubertal juveniles to spawning adults. An additional 13 showed either considerably faster or slower growth and development than the majority of fish. We used histological examination of the ovaries to determine a histological maturation stage, and analyzed the pituitary glands using RNA-seq optimized for low input. Taken together, these data reveal the timing of hormone production priorities, and form a comprehensive resource for the study of their regulation.
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Affiliation(s)
- Eirill Ager-Wick
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Gersende Maugars
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway ,grid.9916.70000 0001 2173 1046Present Address: Stress Environnementaux et BIOsurveillance des milieux aquatiques UMR-I 02 SEBIO, Université Le Havre Normandie, Le Havre, France
| | - Kristine von Krogh
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Romain Fontaine
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Finn-Arne Weltzien
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Christiaan Henkel
- grid.19477.3c0000 0004 0607 975XPhysiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
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8
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Horie Y, Ramaswamy BR, Ríos JM, Yap CK, Okamura H. Effects of plasticizer diisobutyl adipate on the Japanese medaka (Oryzias latipes) endocrine system. J Appl Toxicol 2023. [PMID: 36647207 DOI: 10.1002/jat.4437] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/30/2022] [Accepted: 01/13/2023] [Indexed: 01/18/2023]
Abstract
Plasticizer pollution of the water environment is one of the world's most serious environmental issues. Phthalate plasticizers can disrupt endocrine function in vertebrates. Therefore, this study analyzed thyroid-related, reproduction-related, and estrogen-responsive genes in Japanese medaka (Oryzias latipes) to determine whether non-phthalate diisobutyl adipate (DIBA) plasticizer could affect endocrine hormone activity or not. Developmental toxicity during fish embryogenesis was also evaluated. At a concentration of 11.57 mg/l, embryonic exposure to DIBA increased the mortality rate. Although abnormal development, including body curvature, edema, and lack of swim bladder inflation, was observed at 3.54 and 11.57 mg/l DIBA, growth inhibition and reduced swimming performance were also observed. In addition, DIBA exposure increased the levels of thyroid-stimulating hormone beta-subunit (tshβ) and deiodinase 1 (dio1) but decreased the levels of thyroid hormone receptor alpha (trα) and beta (trβ). These results suggest that DIBA has thyroid hormone-disrupting activities in fish. However, kisspeptin (kiss1 and kiss2), gonadotropin-releasing hormone (gnrh1), follicle-stimulating hormone beta (fshβ), luteinizing hormone beta (lhβ), choriogenin H (chgH), and vitellogenin (vtg1) expression did not change dose-dependently in response to DIBA exposure, whereas gnrh2 and vtg2 expression was elevated. These results indicate that DIBA has low estrogenic activity and does not disrupt the endocrine reproduction system in fish. Overall, this is the first report indicating that non-phthalate DIBA plasticizer is embryotoxic and disrupt thyroid hormone activity in fish.
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Affiliation(s)
- Yoshifumi Horie
- Research Center for Inland Seas (KURCIS), Kobe University, Fukae Minamimachi, Higashinada-ku, Kobe, 658-0022, Japan
| | - Babu Rajendran Ramaswamy
- Research Center for Inland Seas (KURCIS), Kobe University, Fukae Minamimachi, Higashinada-ku, Kobe, 658-0022, Japan.,Department of Environmental Biotechnology, School of Environmental Sciences, Bharathidasan University, Tiruchirappalli, 620024, India
| | - Juan Manuel Ríos
- Laboratorio de Ecotoxicología, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU, CCT-CONICET), 5500, Mendoza, Argentina
| | - Chee Kong Yap
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - Hideo Okamura
- Research Center for Inland Seas (KURCIS), Kobe University, Fukae Minamimachi, Higashinada-ku, Kobe, 658-0022, Japan
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9
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Characterization of hormone-producing cell types in the teleost pituitary gland using single-cell RNA-seq. Sci Data 2021; 8:279. [PMID: 34711832 PMCID: PMC8553774 DOI: 10.1038/s41597-021-01058-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 09/09/2021] [Indexed: 11/08/2022] Open
Abstract
The pituitary is the vertebrate endocrine gland responsible for the production and secretion of several essential peptide hormones. These, in turn, control many aspects of an animal’s physiology and development, including growth, reproduction, homeostasis, metabolism, and stress responses. In teleost fish, each hormone is presumably produced by a specific cell type. However, key details on the regulation of, and communication between these cell types remain to be resolved. We have therefore used single-cell sequencing to generate gene expression profiles for 2592 and 3804 individual cells from the pituitaries of female and male adult medaka (Oryzias latipes), respectively. Based on expression profile clustering, we define 15 and 16 distinct cell types in the female and male pituitary, respectively, of which ten are involved in the production of a single peptide hormone. Collectively, our data provide a high-quality reference for studies on pituitary biology and the regulation of hormone production, both in fish and in vertebrates in general. Measurement(s) | RNA-seq gene expression profiling assay | Technology Type(s) | tag based single cell RNA sequencing | Factor Type(s) | sex | Sample Characteristic - Organism | Oryzias latipes | Sample Characteristic - Environment | fresh water aquarium |
Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.16592621
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10
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Royan MR, Siddique K, Csucs G, Puchades MA, Nourizadeh-Lillabadi R, Bjaalie JG, Henkel CV, Weltzien FA, Fontaine R. 3D Atlas of the Pituitary Gland of the Model Fish Medaka ( Oryzias latipes). Front Endocrinol (Lausanne) 2021; 12:719843. [PMID: 34497587 PMCID: PMC8419251 DOI: 10.3389/fendo.2021.719843] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 07/12/2021] [Indexed: 12/23/2022] Open
Abstract
In vertebrates, the anterior pituitary plays a crucial role in regulating several essential physiological processes via the secretion of at least seven peptide hormones by different endocrine cell types. Comparative and comprehensive knowledge of the spatial distribution of those endocrine cell types is required to better understand their physiological functions. Using medaka as a model and several combinations of multi-color fluorescence in situ hybridization, we present the first 3D atlas revealing the gland-wide distribution of seven endocrine cell populations: lactotropes, thyrotropes, Lh and Fsh gonadotropes, somatotropes, and pomca-expressing cells (corticotropes and melanotropes) in the anterior pituitary of a teleost fish. By combining in situ hybridization and immunofluorescence techniques, we deciphered the location of corticotropes and melanotropes within the pomca-expressing cell population. The 3D localization approach reveals sexual dimorphism of tshba-, pomca-, and lhb-expressing cells in the adult medaka pituitary. Finally, we show the existence of bi-hormonal cells co-expressing lhb-fshb, fshb-tshba and lhb-sl using single-cell transcriptomics analysis and in situ hybridization. This study offers a solid basis for future comparative studies of the teleost pituitary and its functional plasticity.
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Affiliation(s)
- Muhammad Rahmad Royan
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Khadeeja Siddique
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Gergely Csucs
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Maja A. Puchades
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | | | - Jan G. Bjaalie
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Christiaan V. Henkel
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Finn-Arne Weltzien
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Romain Fontaine
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
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11
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Grønlien HK, Fontaine R, Hodne K, Tysseng I, Ager-Wick E, Weltzien FA, Haug TM. Long extensions with varicosity-like structures in gonadotrope Lh cells facilitate clustering in medaka pituitary culture. PLoS One 2021; 16:e0245462. [PMID: 33507913 PMCID: PMC7842944 DOI: 10.1371/journal.pone.0245462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 01/02/2021] [Indexed: 11/19/2022] Open
Abstract
Accumulating evidence indicates that some pituitary cell types are organized in complex networks in both mammals and fish. In this study, we have further investigated the previously described cellular extensions formed by the medaka (Oryzias latipes) luteinizing hormone gonadotropes (Lh cells). Extensions, several cell diameters long, with varicosity-like swellings, were common both in vitro and in vivo. Some extensions approached other Lh cells, while others were in close contact with blood vessels in vivo. Gnrh further stimulated extension development in vitro. Two types of extensions with different characteristics could be distinguished, and were classified as major or minor according to size, origin and cytoskeleton protein dependance. The varicosity-like swellings appeared on the major extensions and were dependent on both microtubules and actin filaments. Immunofluorescence revealed that Lhβ protein was mainly located in these swellings and at the extremity of the extensions. We then investigated whether these extensions contribute to network formation and clustering, by following their development in primary cultures. During the first two days in culture, the Lh cells grew long extensions that with time physically attached to other cells. Successively, tight cell clusters formed as cell somas that were connected via extensions migrated towards each other, while shortening their extensions. Laser photolysis of caged Ca2+ showed that Ca2+ signals originating in the soma propagated from the soma along the major extensions, being particularly visible in each swelling. Moreover, the Ca2+ signal could be transferred between densely clustered cells (sharing soma-soma border), but was not transferred via extensions to the connected cell. In summary, Lh gonadotropes in medaka display a complex cellular structure of hormone-containing extensions that are sensitive to Gnrh, and may be used for clustering and possibly hormone release, but do not seem to contribute to communication between cells themselves.
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Affiliation(s)
| | - Romain Fontaine
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kjetil Hodne
- Physiology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Isabelle Tysseng
- Department of Biosciences, Faculty of Natural Sciences, University of Oslo, Oslo, Norway
| | - Eirill Ager-Wick
- 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
| | - Trude Marie Haug
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
- * E-mail:
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12
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Santiago-Andres Y, Golan M, Fiordelisio T. Functional Pituitary Networks in Vertebrates. Front Endocrinol (Lausanne) 2021; 11:619352. [PMID: 33584547 PMCID: PMC7873642 DOI: 10.3389/fendo.2020.619352] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 12/07/2020] [Indexed: 11/13/2022] Open
Abstract
The pituitary is a master endocrine gland that developed early in vertebrate evolution and therefore exists in all modern vertebrate classes. The last decade has transformed our view of this key organ. Traditionally, the pituitary has been viewed as a randomly organized collection of cells that respond to hypothalamic stimuli by secreting their content. However, recent studies have established that pituitary cells are organized in tightly wired large-scale networks that communicate with each other in both homo and heterotypic manners, allowing the gland to quickly adapt to changing physiological demands. These networks functionally decode and integrate the hypothalamic and systemic stimuli and serve to optimize the pituitary output into the generation of physiologically meaningful hormone pulses. The development of 3D imaging methods and transgenic models have allowed us to expand the research of functional pituitary networks into several vertebrate classes. Here we review the establishment of pituitary cell networks throughout vertebrate evolution and highlight the main perspectives and future directions needed to decipher the way by which pituitary networks serve to generate hormone pulses in vertebrates.
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Affiliation(s)
- Yorgui Santiago-Andres
- Laboratorio de Neuroendocrinología Comparada, Departamento de Ecología y Recursos Naturales, Biología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Matan Golan
- Department of Poultry and Aquaculture, Institute of Animal Sciences, Agricultural Research Organization, Rishon Lezion, Israel
| | - Tatiana Fiordelisio
- Laboratorio de Neuroendocrinología Comparada, Departamento de Ecología y Recursos Naturales, Biología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
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13
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Fontaine R, Ager-Wick E, Hodne K, Weltzien FA. Plasticity in medaka gonadotropes via cell proliferation and phenotypic conversion. J Endocrinol 2020; 245:21-37. [PMID: 31977313 PMCID: PMC7040568 DOI: 10.1530/joe-19-0405] [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: 01/07/2020] [Accepted: 01/23/2020] [Indexed: 01/30/2023]
Abstract
Follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh) produced by the gonadotropes play a major role in control of reproduction. Contrary to mammals and birds, Lh and Fsh are mostly produced by two separate cell types in teleost. Here, we investigated gonadotrope plasticity, using transgenic lines of medaka (Oryzias latipes) where DsRed2 and hrGfpII are under the control of the fshb and lhb promotors respectively. We found that Fsh cells appear in the pituitary at 8 dpf, while Lh cells were previously shown to appear at 14 dpf. Similar to Lh cells, Fsh cells show hyperplasia from juvenile to adult stages. Hyperplasia is stimulated by estradiol. Both Fsh and Lh cells show hypertrophy during puberty with similar morphology. They also share similar behavior, using their cellular extensions to make networks. We observed bi-hormonal gonadotropes in juveniles and adults but not in larvae where only mono-hormonal cells are observed, suggesting the existence of phenotypic conversion between Fsh and Lh in later stages. This is demonstrated in cell culture, where some Fsh cells start to produce Lhβ, a phenomenon enhanced by gonadotropin-releasing hormone (Gnrh) stimulation. We have previously shown that medaka Fsh cells lack Gnrh receptors, but here we show that with time in culture, some Fsh cells start responding to Gnrh, while fshb mRNA levels are significantly reduced, both suggestive of phenotypic change. All together, these results reveal high plasticity of gonadotropes due to both estradiol-sensitive proliferation and Gnrh promoted phenotypic conversion, and moreover, show that gonadotropes lose part of their identity when kept in cell culture.
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Affiliation(s)
- Romain Fontaine
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Eirill Ager-Wick
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kjetil Hodne
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Finn-Arne Weltzien
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
- Correspondence should be addressed to F-A Weltzien:
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14
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Fontaine R, Ciani E, Haug TM, Hodne K, Ager-Wick E, Baker DM, Weltzien FA. Gonadotrope plasticity at cellular, population and structural levels: A comparison between fishes and mammals. Gen Comp Endocrinol 2020; 287:113344. [PMID: 31794734 DOI: 10.1016/j.ygcen.2019.113344] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/27/2019] [Accepted: 11/26/2019] [Indexed: 12/22/2022]
Abstract
Often referred to as "the master gland", the pituitary is a key organ controlling growth, maturation, and homeostasis in vertebrates. The anterior pituitary, which contains several hormone-producing cell types, is highly plastic and thereby able to adjust the production of the hormones governing these key physiological processes according to the changing needs over the life of the animal. Hypothalamic neuroendocrine control and feedback from peripheral tissues modulate pituitary cell activity, adjusting levels of hormone production and release according to different functional or environmental requirements. However, in some physiological processes (e.g. growth, puberty, or metamorphosis), changes in cell activity may be not sufficient to meet the needs and a general reorganization of cell composition and pituitary structure may occur. Focusing on gonadotropes, this review examines plasticity at the cellular level, which allows precise and rapid control of hormone production and secretion, as well as plasticity at the population and structural levels, which allows more substantial changes in hormone production. Further, we compare current knowledge of the anterior pituitary plasticity in fishes and mammals in order to assess what has been conserved or not throughout evolution, and highlight important remaining questions.
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Affiliation(s)
- Romain Fontaine
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Elia Ciani
- Department of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Oslo, 0316 Oslo, Norway
| | - Trude Marie Haug
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway
| | - Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Eirill Ager-Wick
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Dianne M Baker
- Department of Biological Sciences, University of Mary Washington, VA22401 Fredericksburg, VA, USA
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway.
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15
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Hodne K, Fontaine R, Ager-Wick E, Weltzien FA. Gnrh1-Induced Responses Are Indirect in Female Medaka Fsh Cells, Generated Through Cellular Networks. Endocrinology 2019; 160:3018-3032. [PMID: 31621882 DOI: 10.1210/en.2019-00595] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/11/2019] [Indexed: 12/23/2022]
Abstract
Reproductive function in vertebrates is stimulated by GnRH that controls the synthesis and release of the two pituitary gonadotropins, FSH and LH. FSH and LH, which regulate different stages of gonadal development, are produced by two different cell types in the fish pituitary. This is in contrast to the situation in mammals and birds, and it enables investigation of their differential regulation. In the present study, we used fluorescence in situ hybridization to show that Lh cells in adult female medaka express Gnrh receptors, whereas Fsh cells do not. This result was confirmed by patch-clamp recordings and by cytosolic Ca2+ measurements on dispersed pituitary cells, where Lh cells, but not Fsh cells, responded to Gnrh1 by biphasic alteration in action-potential frequencies and cytosolic Ca2+ levels. In contrast, both Fsh and Lh cells are able to respond to Gnrh1 in brain-pituitary tissue slices both electrically and by elevating the cytosolic Ca2+ levels. Using Ca2+ uncaging in combination with patch-clamp recordings and cytosolic Ca2+ measurements, we show that Fsh and Lh cells form homotypic and heterotypic networks in the pituitary. Taken together, these results show that the effects of Gnrh1 on Fsh release in adult female medaka are indirect and probably mediated via Lh cells.
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Affiliation(s)
- Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Romain Fontaine
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Eirill Ager-Wick
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
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16
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Establishment of specific enzyme-linked immunosorbent assay (ELISA) for measuring Fsh and Lh levels in medaka ( Oryzias latipes), using recombinant gonadotropins. MethodsX 2019; 6:1473-1479. [PMID: 31293904 PMCID: PMC6594921 DOI: 10.1016/j.mex.2019.06.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 06/12/2019] [Indexed: 01/09/2023] Open
Abstract
The paucity of information on understanding the regulatory mechanisms that are involved in the control of piscine Fsh and Lh synthesis, secretion, and function, prompted the present work. Part of the problem is related to the molecular heterogeneity and the unavailability of Fsh and Lh assays for quantifying gonadotropins, in particular assays regarding the measurement of Fsh, and such assays are available today for only a few teleost species. The present study reports the development and validation of competitive ELISAs for quantitative determination of medaka Fsh and Lh by first producing medaka recombinant (md) gonadotropins mdFshβ, mdLhβ, mdFshβα, and mdLhβα by Pichia pastoris, generating specific antibodies against their respective β subunits, and their use within the development of ELISAs. The advantages of this protocol include: The reproducibility of the ELISA demonstrated was relatively high, as shown by reasonably low intra- (Fsh 2.7%, Lh 3%) and interassay CVs (Fsh 5.3%, Lh 5.7%). The high degree of parallelism between serial dilutions of the recombinant and native pituitary-derived Fsh and Lh, may be a sign of similar structures and immunologically similarity. Two new competitive ELISAs for the quantification of medaka Fsh and Lh were established for the first time.
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17
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Fontaine R, Ager-Wick E, Hodne K, Weltzien FA. Plasticity of Lh cells caused by cell proliferation and recruitment of existing cells. J Endocrinol 2019; 240:361-377. [PMID: 30594119 DOI: 10.1530/joe-18-0412] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 11/30/2018] [Indexed: 01/23/2023]
Abstract
Luteinizing hormone (Lh) and follicle-stimulating hormone (Fsh) control reproduction in vertebrates. Using a transgenic line of medaka, in which green fluorescent protein expression is controlled by the endogenous lhb promotor, we studied development and plasticity of Lh cells, comparing juveniles and adults of both genders. Confocal imaging and 3D reconstruction revealed hypertrophy and hyperplasia of Lh cells in both genders from juvenile to adult stages. We show that Lh cell hyperplasia may be caused by recruitment of existing pituitary cells that start to produce lhb, as evidenced by time lapse recordings of primary pituitary cell cultures, and/or through Lh cell proliferation, demonstrated through a combination of 5-bromo-2'-deoxyuridine incubation experiments and proliferating cell nuclear antigen staining. Proliferating Lh cells do not belong to the classical type of multipotent stem cells, as they do not stain with anti-sox2. Estradiol exposure in vivo increased pituitary cell proliferation, particularly Lh cells, whereas pituitary lhb and gpa expression levels decreased. RNA-seq and in situ hybridization showed that Lh cells express two estrogen receptors, esr1 and esr2b, and the aromatase gene cyp19a1b, suggesting a direct effect of estradiol, and possibly androgens, on Lh cell proliferation. In conclusion, our study reveals a high degree of plasticity in the medaka Lh cell population, resulting from a combination of recruitment and cell proliferation.
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Affiliation(s)
- Romain Fontaine
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Eirill Ager-Wick
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
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18
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Burow S, Fontaine R, von Krogh K, Mayer I, Nourizadeh-Lillabadi R, Hollander-Cohen L, Cohen Y, Shpilman M, Levavi-Sivan B, Weltzien FA. Medaka follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh): Developmental profiles of pituitary protein and gene expression levels. Gen Comp Endocrinol 2019; 272:93-108. [PMID: 30576646 DOI: 10.1016/j.ygcen.2018.12.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/30/2018] [Accepted: 12/16/2018] [Indexed: 02/06/2023]
Abstract
The two gonadotropins follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh) are of particular importance within the hypothalamic-pituitary-gonadal (HPG) axis of vertebrates. In the current study, we demonstrate the production and validation of Japanese medaka (Oryzias latipes) recombinant (md) gonadotropins Fshβ (mdFshβ), Lhβ (mdLhβ), Fshβα (mdFshβα), and Lhβα (mdLhβα) by Pichia pastoris, the generation of specific rabbit antibodies against their respective β subunits, and their use within the development and validation of competitive enzyme-linked immunosorbent assays (ELISAs) for quantification of medaka Fsh and Lh. mdFsh and mdLh were produced as single-chain polypeptides by linking the α subunit with mdFshβ or mdLhβ mature protein coding sequences to produce a "tethered" polypeptide with the β-chain at the N-terminal and the α-chain at the C-terminal. The specificity of the antibodies raised against mdFshβ and mdLhβ was determined by immunofluorescence (IF) for Fshβ and Lhβ on medaka pituitary tissue, while comparison with fluorescence in situ hybridization (FISH) for fshb and lhb mRNA was used for validation. Competitive ELISAs were developed using antibodies against mdFshβ or mdLhβ, and the tethered proteins mdFshβα or mdLhβα for standard curves. The standard curve for the Fsh ELISA ranged from 97.6 pg/ml to 50 ng/ml, and for the Lh ELISA from 12.21 pg/ml to 6.25 ng/ml. The sensitivity of the assays for Fsh and Lh was 44.7 and 70.8 pg/ml, respectively. A profile of pituitary protein levels of medaka Fsh and Lh comparing juveniles with adults showed significant increase of protein amount from juvenile group (body length from 12 mm to 16.5 mm) to adult group (body length from 21 mm to 26.5 mm) for both hormones in male medaka. Comparing these data to a developmental profile of pituitary mRNA expression of medaka fshb and lhb, the mRNA expression of lhb also increased during male maturation and a linear regression analysis revealed a significant increase of lhb expression with increased body length that proposes a linear model. However, fshb mRNA expression did not change significantly during male development and therefore was not correlated with body length. In summary, we have developed and validated homologous ELISA assays for medaka Fsh and Lh based on proteins produced in P. pastoris, assays that will be used to study the functions and regulations of Fsh and Lh in more detail.
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Affiliation(s)
- Susann Burow
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Romain Fontaine
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Kristine von Krogh
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Ian Mayer
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Rasoul Nourizadeh-Lillabadi
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Lian Hollander-Cohen
- Department of Animal Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 76100, Israel
| | - Yaron Cohen
- Department of Animal Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 76100, Israel
| | - Michal Shpilman
- Department of Animal Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 76100, Israel
| | - Berta Levavi-Sivan
- Department of Animal Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 76100, Israel
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway.
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19
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Ager-Wick E, Hodne K, Fontaine R, von Krogh K, Haug TM, Weltzien FA. Preparation of a High-quality Primary Cell Culture from Fish Pituitaries. J Vis Exp 2018. [PMID: 30222142 DOI: 10.3791/58159] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Primary cell culture is a powerful tool commonly used by scientists to study cellular properties and mechanisms of isolated cells in a controlled environment. Despite vast differences in the physiology between mammals and fish, primary cell culture protocols from fish are often based on mammalian culture conditions, often with only minor modifications. The environmental differences affect not only body temperature, but also blood serum parameters such as osmolality, pH, and pH buffer capacity. As cell culture media and similar working solutions are meant to mimic characteristics of the extracellular fluid and/or blood serum to which a cell is adapted, it is crucial that these parameters are adjusted specifically to the animal in question. The current protocol describes optimized primary culture conditions for medaka (Oryzias latipes). The protocol provides detailed steps on how to isolate and maintain healthy dissociated pituitary cells for more than one week and includes the following steps: 1. the adjustment of the osmolality to the values found in medaka blood plasma, 2. the adjustment of the incubation temperature to normal medaka temperature (here in the aquarium facility), and 3. the adjustment of the pH and bicarbonate buffer to values comparable to other fish species living at similar temperatures. The results presented using the described protocol promote physiologically meaningful results for medaka and can be used as a reference guide by scientists making primary cell cultures from other non-mammalian species.
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Affiliation(s)
- Eirill Ager-Wick
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences
| | - Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences
| | - Romain Fontaine
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences
| | - Kristine von Krogh
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences
| | - Trude M Haug
- Department of Oral Biology, Faculty of Dentistry, University of Oslo
| | - Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences;
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20
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Zhu B, Ge W. Genome editing in fishes and their applications. Gen Comp Endocrinol 2018; 257:3-12. [PMID: 28919449 DOI: 10.1016/j.ygcen.2017.09.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 08/15/2017] [Accepted: 09/13/2017] [Indexed: 12/18/2022]
Abstract
There have been revolutionary progresses in genome engineering in the past few years. The newly-emerged genome editing technologies including zinc-finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN) and clustered regularly interspaced short palindromic repeats associated with Cas9 (CRISPR/Cas9) have enabled biological scientists to perform efficient and precise targeted genome editing in different species. Fish represent the largest group of vertebrates with many species having values for both scientific research and aquaculture industry. Genome editing technologies have found extensive applications in different fish species for basic functional studies as well asapplied research in such fields as disease modeling and aquaculture. This mini-review focuses on recent advancements and applications of the new generation of genome editing technologies in fish species, with particular emphasis on their applications in understanding reproductive functions because the reproductive axis has been most systematically and best studied among others and its function has been difficult to address with reverse genetics approach.
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Affiliation(s)
- Bo Zhu
- Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Wei Ge
- Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Taipa, Macau, China.
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21
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Strandabø RAU, Grønlien HK, Ager-Wick E, Nourizadeh-Lillabadi R, Hildahl JP, Weltzien FA, Haug TM. Identified lhb-expressing cells from medaka (Oryzias latipes) show similar Ca(2+)-response to all endogenous Gnrh forms, and reveal expression of a novel fourth Gnrh receptor. Gen Comp Endocrinol 2016; 229:19-31. [PMID: 26899720 DOI: 10.1016/j.ygcen.2016.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 02/15/2016] [Accepted: 02/16/2016] [Indexed: 01/12/2023]
Abstract
We have previously characterized the response to gonadotropin-releasing hormone (Gnrh) 2 in luteinizing hormone (lhb)-expressing cells from green fluorescent protein (Gfp)-transgenic medaka (Oryzias latipes), with regard to changes in the cytosolic Ca(2+) concentration. In the current study we present the corresponding responses to Gnrh1 and Gnrh3. Ca(2+) imaging revealed three response patterns to Gnrh1 and Gnrh3, one monophasic and two types of biphasic patterns. There were few significant differences in the shape of the response patterns between the three Gnrh forms, although the amplitude of the Ca(2+) signal was considerably lower for Gnrh1 and Gnrh3 than for Gnrh2, and the distribution between the two different biphasic patterns differed. The different putative Ca(2+) sources were examined by depleting intracellular Ca(2+) stores with thapsigargin, or preventing influx of extracellular Ca(2+) by either extracellular Ca(2+) depletion or the L-type Ca(2+)-channel blocker verapamil. Both Gnrh1 and 3 relied on Ca(2+) from both intracellular and extracellular sources, with some unexpected differences in the relative contribution. Furthermore, gene expression of Gnrh-receptors (gnrhr) in whole pituitaries was studied during development from juvenile to adult. Only two of the four identified medaka receptors were expressed in the pituitary, gnrhr1b and gnrhr2a, with the newly discovered gnrhr2a showing the highest expression level at all stages as analyzed by quantitative PCR. While both receptors differed in expression level according to developmental stage, only the expression of gnrhr2a showed a clear-cut increase with gonadal maturation. RNA sequencing analysis of FACS-sorted Gfp-positive lhb-cells revealed that both gnrhr1b and gnrhr2a were expressed in lhb-expressing cells, and confirmed the higher expression of gnrhr2a compared to gnrhr1b. These results show that although lhb-expressing gonadotropes in medaka show similar Ca(2+) response patterns to all three endogenous Gnrh forms through the activation of two different receptors, gnrhr1b and gnrhr2a, the differences observed between the Gnrh forms indicate activation of different Ca(2+) signaling pathways.
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Affiliation(s)
- Rønnaug A U Strandabø
- University of Oslo, Department of Biosciences, P.O. Box 1066 Blindern, N-0316 Oslo, Norway
| | - Heidi K Grønlien
- Østfold University College, Faculty of Health and Social Studies, P.O. 700, N-1757 Halden, Norway
| | - Eirill Ager-Wick
- Norwegian University of Life Sciences, Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep, N-0033 Oslo, Norway
| | - Rasoul Nourizadeh-Lillabadi
- Norwegian University of Life Sciences, Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep, N-0033 Oslo, Norway
| | - Jon P Hildahl
- University of Oslo, Department of Biosciences, P.O. Box 1066 Blindern, N-0316 Oslo, Norway
| | - Finn-Arne Weltzien
- Norwegian University of Life Sciences, Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep, N-0033 Oslo, Norway
| | - Trude M Haug
- University of Oslo, Department of Biosciences, P.O. Box 1066 Blindern, N-0316 Oslo, Norway; Atlantis Medical University College, P.O. Box 509, N-1411 Kolbotn, Norway.
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22
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Ager-Wick E, Henkel CV, Haug TM, Weltzien FA. Using normalization to resolve RNA-Seq biases caused by amplification from minimal input. Physiol Genomics 2014; 46:808-20. [PMID: 25228281 DOI: 10.1152/physiolgenomics.00196.2013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RNA-Seq has become a widely used method to study transcriptomes, and it is now possible to perform RNA-Seq on almost any sample. Nevertheless, samples obtained from small cell populations are particularly challenging, as biases associated with low amounts of input RNA can have strong and detrimental effects on downstream analyses. Here we compare different methods to normalize RNA-Seq data obtained from minimal input material. Using RNA from isolated medaka pituitary cells, we have amplified material from six samples before sequencing. Both synthetic and real data are used to evaluate different normalization methods to obtain a robust and reliable pipeline for analysis of RNA-Seq data from samples with very limited input material. The analysis outlined here shows that quantile normalization outperforms other more commonly used normalization procedures when using amplified RNA as input and will benefit researchers employing low amounts of RNA in similar experiments.
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Affiliation(s)
- Eirill Ager-Wick
- Weltzien Laboratory, Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Christiaan V Henkel
- Weltzien Laboratory, Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway; Institute of Biology, Leiden University, Leiden, The Netherlands; and
| | - Trude M Haug
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Finn-Arne Weltzien
- Weltzien Laboratory, Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway
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23
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Horie Y, Shimizu A, Adachi S, Kobayashi T. Expression and localization of gonadotropic hormone subunits (Gpa, Fshb, and Lhb) in the pituitary during gonadal differentiation in medaka. Gen Comp Endocrinol 2014; 204:173-80. [PMID: 24859259 DOI: 10.1016/j.ygcen.2014.04.036] [Citation(s) in RCA: 13] [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: 07/05/2013] [Revised: 04/03/2014] [Accepted: 04/25/2014] [Indexed: 11/16/2022]
Abstract
To clarify the appearance of and chronological changes in two different gonadotropic hormone (Gth) cells, we examined the dynamics of Gth cells in detail during gonadal differentiation and development in the d-rR strain of medaka (Oryzias latipes). Expression of the sex-determining gene Dmy was evident in gonadal somatic cells at 5 days post-fertilization (dpf). Glycoprotein-α (Gpa)-positive cells first appeared in the pituitary at 4 dpf, regardless of genetic sex, while follicle-stimulating hormone-β (Fshb)-positive cells was detected in XX and XY embryos at 5 and 6 dpf, respectively. In contrast, luteinizing hormone-β (Lhb)-positive cells were observed in both sexes of medaka after 70 days post-hatching (dph). The density of Fshb-positive cells in the pituitary was significantly and transiently higher in XX than in XY fry at 0 dph, and thereafter no significant differences were detected before sexual maturation. In this study, temporal expression of Fshb was observed, indicating that Fsh cells become differentiated before hatching and that sexual dimorphism in Fsh cells occurs transiently after sex determination in medaka.
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Affiliation(s)
- Yoshifumi Horie
- Laboratory of Molecular Reproductive Biology, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Akio Shimizu
- Research Center for Aquatic Genomes, National Research Institute of Fisheries Science, Fisheries Research Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan
| | - Shinji Adachi
- Division of Marine Life Sciences, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan
| | - Tohru Kobayashi
- Laboratory of Molecular Reproductive Biology, Institute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan; Laboratory of Molecular Reproductive Biology, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
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Horie Y, Kobayashi T. Relationships between gonadal and gonadotrophic differentiation during early gonadal sex differentiation in several strains from the Southern population of Japanese medaka (Oryzias latipes). ACTA ACUST UNITED AC 2014; 321:472-7. [DOI: 10.1002/jez.1879] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 05/14/2014] [Accepted: 06/06/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Yoshifumi Horie
- Laboratory of Molecular Reproductive Biology; Graduate School of Integrated Pharmaceutical and Nutritional Sciences; University of Shizuoka; Shizuoka Japan
| | - Tohru Kobayashi
- Laboratory of Molecular Reproductive Biology; Institute for Environmental Sciences; University of Shizuoka; Shizuoka Japan
- Laboratory of Molecular Reproductive Biology; Graduate Division of Nutritional and Environmental Sciences; University of Shizuoka; Shizuoka Japan
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Weltzien FA, Hildahl J, Hodne K, Okubo K, Haug TM. Embryonic development of gonadotrope cells and gonadotropic hormones--lessons from model fish. Mol Cell Endocrinol 2014; 385:18-27. [PMID: 24145126 DOI: 10.1016/j.mce.2013.10.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 09/30/2013] [Accepted: 10/11/2013] [Indexed: 01/05/2023]
Abstract
Pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), are key regulators of vertebrate reproduction. The differential regulation of these hormones, however, is poorly understood and little is known about gonadotrope embryonic development. The different cell types in the vertebrate pituitary develop from common progenitor cells just after gastrulation. Proper development and merging of the anterior and posterior pituitary is dependent upon carefully regulated cell-to-cell interactions, and a suite of signaling pathways with precisely organized temporal and spatial expression patterns, which include transcription factors and their co-activators and repressors. Among the pituitary endocrine cell types, the gonadotropes are the last to develop and become functional. Although much progress has been made during the last decade regarding details of gonadotrope development, the coordinated program for their maturation is not well described. FSH and LH form an integral part of the hypothalamo-pituitary-gonad axis, the main regulator of gonad development and reproduction. Besides regulating gonad development, pre- and early post-natal activity in this axis is thought to be essential for proper development, especially of the central nervous system in mammals. As a means to investigate early functions of FSH and LH in more detail, we have developed a stable transgenic line of medaka with the LH beta subunit gene (lhb) promoter driving green fluorescent protein (Gfp) expression to characterize development of lhb-expressing gonadotropes. The lhb gene is maternally expressed early during embryogenesis. lhb-Expressing cells are initially localized outside the primordial pituitary in the developing gut tube as early as 32 hpf. At hatching, lhb-Gfp is clearly detected in the gut epithelium and in the anterior digestive tract. lhb-Gfp expression later consolidates in the developing pituitary by 2 weeks post-fertilization. This review discusses status of knowledge regarding pituitary morphology and development, with emphasis on gonadotrope cells and gonadotropins during early development, comparing main model species like mouse, zebrafish and medaka, including possible developmental functions of the observed extra pituitary expression of lhb in medaka.
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Affiliation(s)
- Finn-Arne Weltzien
- Department of Basic Sciences and Aquatic Medicine, Weltzien Laboratory, Norwegian School of Veterinary Science, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway.
| | - Jon Hildahl
- Department of Basic Sciences and Aquatic Medicine, Weltzien Laboratory, Norwegian School of Veterinary Science, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway
| | - Kjetil Hodne
- Department of Basic Sciences and Aquatic Medicine, Weltzien Laboratory, Norwegian School of Veterinary Science, Oslo, Norway
| | - Kataaki Okubo
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Trude M Haug
- Department of Biosciences, University of Oslo, Oslo, Norway
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Golan M, Biran J, Levavi-Sivan B. A novel model for development, organization, and function of gonadotropes in fish pituitary. Front Endocrinol (Lausanne) 2014; 5:182. [PMID: 25379037 PMCID: PMC4206999 DOI: 10.3389/fendo.2014.00182] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/08/2014] [Indexed: 11/24/2022] Open
Abstract
The gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are key regulators of the reproductive axis in vertebrates. Despite the high popularity of zebrafish as a model organism for studying reproductive functions, to date no transgenic zebrafish with labeled gonadotropes have been introduced. Using gonadotropin regulatory elements from tilapia, we generated two transgenic zebrafish lines with labeled gonadotropes. The tilapia and zebrafish regulatory sequences were highly divergent but several conserved elements allowed the tilapia promoters to correctly drive the transgenes in zebrafish pituitaries. FSH cells reacted to stimulation with gonadotropin releasing hormone by proliferating and showing increased transgene fluorescence, whereas estrogen exposure caused a decrease in cell number and transgene fluorescence. Transgene fluorescence reflected the expression pattern of the endogenous fshb gene. Ontogenetic expression of the transgenes followed typical patterns, with FSH cells appearing early in development, and LH cells appearing later and increasing dramatically in number with the onset of puberty. Our transgenic lines provide a powerful tool for investigating the development, anatomy, and function of the reproductive axis in lower vertebrates.
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Affiliation(s)
- Matan Golan
- Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Jakob Biran
- Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Berta Levavi-Sivan
- Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
- *Correspondence: Berta Levavi-Sivan, Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University, P.O. Box 12, Rehovot 76100, Israel e-mail:
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Strandabø RAU, Hodne K, Ager-Wick E, Sand O, Weltzien FA, Haug TM. Signal transduction involved in GnRH2-stimulation of identified LH-producing gonadotropes from lhb-GFP transgenic medaka (Oryzias latipes). Mol Cell Endocrinol 2013; 372:128-39. [PMID: 23562421 DOI: 10.1016/j.mce.2013.03.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 02/21/2013] [Accepted: 03/26/2013] [Indexed: 12/28/2022]
Abstract
We have characterized the response to gonadotropin-releasing hormone 2 (GnRH2) in luteinizing hormone producing cells from gfp-transgenic medaka. Teleosts have separate cells producing the two types of gonadotropins, enabling us for the first time to study the intracellular signaling that controls secretion of each gonadotropin separately. Pituitary cell cultures were prepared, and lhb-producing cells were selected by their GFP expression. Cytosolic Ca(2+) imaging revealed three response patterns to GnRH2, one monophasic and two types of biphasic patterns. The Ca(2+) sources were examined by depleting intracellular Ca(2+) stores and preventing influx of extracellular Ca(2+). Both treatments reduced response amplitude, and affected latency and time to peak. Blocking L-type Ca(2+) channels reduced amplitude and time to peak, but did not remove extracellular Ca(2+) contribution. Patch-clamp recordings showed spontaneous action potentials in several cells, and GnRH2 increased the firing frequency. Presence of Ca(2+)-activated K(+) channels was revealed, BK channels being the most prominent.
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