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Kovács A, Szabó E, László K, Kertes E, Zagorácz O, Mintál K, Tóth A, Gálosi R, Berta B, Lénárd L, Hormay E, László B, Zelena D, Tóth ZE. Brain RFamide Neuropeptides in Stress-Related Psychopathologies. Cells 2024; 13:1097. [PMID: 38994950 PMCID: PMC11240450 DOI: 10.3390/cells13131097] [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: 04/29/2024] [Revised: 06/21/2024] [Accepted: 06/22/2024] [Indexed: 07/13/2024] Open
Abstract
The RFamide peptide family is a group of proteins that share a common C-terminal arginine-phenylalanine-amide motif. To date, the family comprises five groups in mammals: neuropeptide FF, LPXRFamides/RFamide-related peptides, prolactin releasing peptide, QRFP, and kisspeptins. Different RFamide peptides have their own cognate receptors and are produced by different cell populations, although they all can also bind to neuropeptide FF receptors with different affinities. RFamide peptides function in the brain as neuropeptides regulating key aspects of homeostasis such as energy balance, reproduction, and cardiovascular function. Furthermore, they are involved in the organization of the stress response including modulation of pain. Considering the interaction between stress and various parameters of homeostasis, the role of RFamide peptides may be critical in the development of stress-related neuropathologies. This review will therefore focus on the role of RFamide peptides as possible key hubs in stress and stress-related psychopathologies. The neurotransmitter coexpression profile of RFamide-producing cells is also discussed, highlighting its potential functional significance. The development of novel pharmaceutical agents for the treatment of stress-related disorders is an ongoing need. Thus, the importance of RFamide research is underlined by the emergence of peptidergic and G-protein coupled receptor-based therapeutic targets in the pharmaceutical industry.
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Affiliation(s)
- Anita Kovács
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Evelin Szabó
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Kristóf László
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Erika Kertes
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Olga Zagorácz
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Kitti Mintál
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Attila Tóth
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Rita Gálosi
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Bea Berta
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - László Lénárd
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Edina Hormay
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Bettina László
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Dóra Zelena
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (A.K.); (E.S.); (K.L.); (E.K.); (O.Z.); (K.M.); (A.T.); (R.G.); (B.B.); (L.L.); (E.H.); (B.L.)
| | - Zsuzsanna E. Tóth
- Department of Anatomy, Histology and Embryology, Semmelweis University, H1094 Budapest, Hungary
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Evans MC, Anderson GM. The Role of RFRP Neurons in the Allostatic Control of Reproductive Function. Int J Mol Sci 2023; 24:15851. [PMID: 37958834 PMCID: PMC10648169 DOI: 10.3390/ijms242115851] [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: 10/02/2023] [Revised: 10/30/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
Reproductive function is critical for species survival; however, it is energetically costly and physically demanding. Reproductive suppression is therefore a physiologically appropriate adaptation to certain ecological, environmental, and/or temporal conditions. This 'allostatic' suppression of fertility enables individuals to accommodate unfavorable reproductive circumstances and safeguard survival. The mechanisms underpinning this reproductive suppression are complex, yet culminate with the reduced secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus, which in turn suppresses gonadotropin release from the pituitary, thereby impairing gonadal function. The focus of this review will be on the role of RFamide-related peptide (RFRP) neurons in different examples of allostatic reproductive suppression. RFRP neurons release the RFRP-3 peptide, which negatively regulates GnRH neurons and thus appears to act as a 'brake' on the neuroendocrine reproductive axis. In a multitude of predictable (e.g., pre-puberty, reproductive senescence, and seasonal or lactational reproductive quiescence) and unpredictable (e.g., metabolic, immune and/or psychosocial stress) situations in which GnRH secretion is suppressed, the RFRP neurons have been suggested to act as modulators. This review examines evidence for and against these roles.
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Affiliation(s)
| | - Greg M. Anderson
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand;
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A mammalian gonadotropin-inhibitory hormone homolog RFamide-related peptide 3 regulates pain and anxiety in mice. Cell Tissue Res 2023; 391:159-172. [PMID: 36355189 DOI: 10.1007/s00441-022-03695-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 10/07/2022] [Indexed: 11/12/2022]
Abstract
RFamide-related peptide (RFRP) is a homologous neuropeptide to gonadotropin-inhibitory hormone (GnIH), which is a hypothalamic neuropeptide that negatively regulates the hypothalamic-pituitary-gonadal axis. RFRP/GnIH is thought to be the mediator of stress because various stressors increase RFRP/GnIH mRNA expression and/or RFRP/GnIH neuronal activities. RFRP/GnIH may also directly regulate behavior, because RFRP/GnIH neuronal fibers and RFRP/GnIH receptor are widely expressed in the brain. Here, we create a RFRP/GnIH knockout (GnIH-KO) mice and conduct various behavioral tests. Dense RFRP/GnIH neuronal fibers are located in the limbic system and broad areas in the thalamus, hypothalamus, and midbrain in wild-type mice but not in RFRP/GnIH-KO mice. Spatial working memory is not improved in GnIH-KO mice as shown by Y-maze test. GnIH-KO mice perform intensive wheel running exercise for several hours after light-off. Hot plate test shows that GnIH-KO mice have decreased sensitivity to pain and central administration of RFRP3 to GnIH-KO mice recovers pain sensitivity. Elevated plus maze test shows that GnIH-KO mice have decreased level of anxiety and central administration of RFRP3 to GnIH-KO mice recovers anxiety level. These results indicate that RFRP3 regulates pain and anxiety in mice. RFRP3 may be involved in the negative regulation of spontaneous activity in addition to negatively regulating the reproductive neuroendocrine axis in stressful conditions.
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Zhao X, Si L, Niu L, Wei M, Wang F, Liu X, Chen Z, Qiao Y, Cheng L, Yang S. Effects of RFRP‑3 on an ovariectomized estrogen‑primed rat model and HEC‑1A human endometrial carcinoma cells. Exp Ther Med 2022; 25:76. [PMID: 36684658 PMCID: PMC9842939 DOI: 10.3892/etm.2022.11775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 11/10/2022] [Indexed: 12/24/2022] Open
Abstract
The hypothalamic peptide gonadotropin inhibitory hormone (GnIH) is a relatively novel hypothalamic neuropeptide, identified in 2000. It can influence the hypothalamic-pituitary-gonadal axis and reproductive function through various neuroendocrine systems. The present study aimed to explore the effects and potential underlying molecular mechanism of RFamide-related peptide-3 (RFRP-3) injection on the uterine fluid protein profile of ovariectomized estrogen-primed (OEP) rats using proteomics. In addition, the possible effects of RFRP-3 on the viability and apoptosis of the human endometrial cancer cell line HEC-1A and associated molecular mechanism were investigated. The OEP rat model was established through injection with GnIH/RFRP-3 through the lateral ventricle. At 6 h after injection, the protein components of uterine fluid of rats in the experimental and control groups were analyzed using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). Differentially expressed proteins (DEPs) were analyzed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Protein-protein interactions (PPI) were investigated using the STRING database. PPI networks were then established before hub proteins were selected using OmicsBean software. The expression of one of the hub proteins, Kras, was then detected using western blot analysis. Cell Counting Kit-8, Annexin V-FITC/PI, reverse transcription-quantitative PCR and western blotting were also performed to analyze cell viability and apoptosis. In total, 417 DEPs were obtained using LC-MS/MS, including 279 upregulated and 138 downregulated proteins. GO analysis revealed that the majority of the DEPs were secretory proteins. According to KEGG enrichment analysis, the DEPs found were generally involved in tumor-associated pathways. In particular, five hub proteins, namely G protein subunit α (Gna)13, Gnaq, Gnai3, Kras and MMP9, were obtained following PPI network analysis. Western blot analysis showed that expression of the hub protein Kras was downregulated following treatment with 10,000 ng/ml RFRP-3. RFRP-3 treatment (10,000 ng/ml) also suppressed HEC-1A cell viability, induced apoptosis, downregulated Bcl-2 and upregulated Bax protein expression, compared with those in the control group. In addition, compared with those in the control group, RFRP-3 significantly reduced the mRNA expression levels of PI3K, AKT and mTOR, while upregulating those of LC3-II. Compared with those in the control group, RFRP-3 significantly decreased the protein expression levels of PI3K, AKT, mTOR and p62, in addition to decreasing AKT phosphorylation. By contrast, RFRP-3 significantly increased the LC3-II/I ratio and G protein-coupled receptor 147 (GPR147) protein expression. In conclusion, the present data suggest that RFRP-3 can alter the protein expression profile of the uterine fluid of OEP rats by upregulating MMP9 expression whilst downregulating that of key hub proteins Gna13, GnaQ, Gnai3 and Kras. Furthermore, RFRP-3 can inhibit HEC-1A cell viability while promoting apoptosis. The underlying molecular mechanism may involve activation of GPR147 receptor by the direct binding of RFRP-3, which further downregulates the hub protein Kras to switch on the PI3K/AKT/mTOR pathway. This subsequently reduces the Bcl-2 expression and promotes Bax expression to induce autophagy.
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Affiliation(s)
- Xueying Zhao
- Department of Immunology, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Lina Si
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Lin Niu
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Meng Wei
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Fengxia Wang
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Xiaochao Liu
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Zhihong Chen
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Yuebing Qiao
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China
| | - Luyang Cheng
- Department of Immunology, Chengde Medical University, Chengde, Hebei 067000, P.R. China,Correspondence to: Mrs. Luyang Cheng, Department of Immunology, Chengde Medical University, Anyuan Road, Shuangqiao, Chengde, Hebei 067000, P.R. China
| | - Songhe Yang
- Department of Human Anatomy, Chengde Medical University, Chengde, Hebei 067000, P.R. China,Correspondence to: Mrs. Luyang Cheng, Department of Immunology, Chengde Medical University, Anyuan Road, Shuangqiao, Chengde, Hebei 067000, P.R. China
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Singh P, Anjum S, Srivastava RK, Tsutsui K, Krishna A. Central and peripheral neuropeptide RFRP-3: A bridge linking reproduction, nutrition, and stress response. Front Neuroendocrinol 2022; 65:100979. [PMID: 35122778 DOI: 10.1016/j.yfrne.2022.100979] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/30/2021] [Accepted: 01/06/2022] [Indexed: 02/06/2023]
Abstract
This article is an amalgamation of the current status of RFRP-3 (GnIH) in reproduction and its association with the nutrition and stress-mediated changes in the reproductive activities. GnIH has been demonstrated in the hypothalamus of all the vertebrates studied so far and is a well-known inhibitor of GnRH mediated reproduction. The RFRP-3 neurons interact with the other hypothalamic neurons and the hormonal signals from peripheral organs for coordinating the nutritional, stress, and environmental associated changes to regulate reproduction. RFRP-3 has also been shown to regulate puberty, reproductive cyclicity and senescence depending upon the nutritional status. A favourable nutritional status and the environmental cues which are permissive for the successful breeding and pregnancy outcome keep RFRP-3 level low, whereas unfavourable nutritional status and stressful conditions increase the expression of RFRP-3 which impairs the reproduction. Still our knowledge about RFRP-3 is incomplete regarding its therapeutic application for nutritional or stress-related reproductive disorders.
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Affiliation(s)
- Padmasana Singh
- Department of Zoology, Indira Gandhi National Tribal University, Amarkantak, Anuppur 484886, MP, India
| | - Shabana Anjum
- Department of Chemical Engineering, American University of Sharjah, Sharjah 26666, United Arab Emirates
| | - Raj Kamal Srivastava
- Department of Zoology, Indira Gandhi National Tribal University, Amarkantak, Anuppur 484886, MP, India
| | - Kazuyoshi Tsutsui
- Department of Biology and Center for Medical Life Science, Waseda University, Kagamiyama 1-7-1, Higashi-Hiroshima University 739-8521, Japan
| | - Amitabh Krishna
- Department of Zoology, Banaras Hindu University, Varanasi 221005, UP, India.
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Regulation of stress response on the hypothalamic-pituitary-gonadal axis via gonadotropin-inhibitory hormone. Front Neuroendocrinol 2022; 64:100953. [PMID: 34757094 DOI: 10.1016/j.yfrne.2021.100953] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/16/2021] [Accepted: 10/24/2021] [Indexed: 11/21/2022]
Abstract
Under stressful condition, reproductive function is impaired due to the activation of various components of the hypothalamic-pituitaryadrenal (HPA) axis, which can suppress the activity of the hypothalamic-pituitary-gonadal (HPG) axis at multiple levels. A hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH) is a key negative regulator of reproduction that governs the HPG axis. Converging lines of evidence have suggested that different stress types and their duration, such as physical or psychological, and acute or chronic, can modulate the GnIH system. To clarify the sensitivity and reactivity of the GnIH system in response to stress, we summarize and critically review the available studies that investigated the effects of various stressors, such as restraint, nutritional/metabolic and social stress, on GnIH expression and/or its neuronal activity leading to altered HPG action. In this review, we focus on GnIH as the potential novel mediator responsible for stress-induced reproductive dysfunction.
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Mohapatra SS, Mukherjee J, Banerjee D, Das PK, Ghosh PR, Das K. RFamide peptides, the novel regulators of mammalian HPG axis: A review. Vet World 2021; 14:1867-1873. [PMID: 34475710 PMCID: PMC8404114 DOI: 10.14202/vetworld.2021.1867-1873] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 06/10/2021] [Indexed: 01/04/2023] Open
Abstract
The RFamide-related peptides (RFRPs) are the group of neuropeptides synthesized predominantly from the hypothalamus that negatively affects the hypothalamo-hypophyseal-gonadal (hypothalamic–pituitary–gonadal [HPG]) axis. These peptides are first identified in quail brains and emerged as the mammalian orthologs of avian gonadotropin inhibitory hormones. The RFRP-3 neurons in the hypothalamus are present in several mammalian species. The action of RFRP-3 is mediated through a G-protein-coupled receptor called OT7T022. The predominant role of RFRP-3 is the inhibition of HPG axis with several other effects such as the regulation of metabolic activity, stress regulation, controlling of non-sexual motivated behavior, and sexual photoperiodicity in concert with other neuropeptides such as kisspeptin, neuropeptide-Y (NPY), pro-opiomelanocortin, orexin, and melanin. RFamide peptides synthesized in the granulosa cells, interstitial cells, and seminiferous tubule regulate steroidogenesis and gametogenesis in the gonads. The present review is intended to provide the recent findings that explore the role of RFRP-3 in regulating HPG axis and its potential applications in the synchronization of reproduction and its therapeutic interventions to prevent stress-induced amenorrhea.
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Affiliation(s)
- Smruti Smita Mohapatra
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
| | - Joydip Mukherjee
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
| | - Dipak Banerjee
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
| | - Pradip Kumar Das
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
| | - Prabal Ranjan Ghosh
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
| | - Kinsuk Das
- Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India
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Faykoo-Martinez M, Kalinowski LM, Holmes MM. Neuroendocrine regulation of pubertal suppression in the naked mole-rat: What we know and what comes next. Mol Cell Endocrinol 2021; 534:111360. [PMID: 34116130 DOI: 10.1016/j.mce.2021.111360] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/20/2021] [Accepted: 06/03/2021] [Indexed: 01/13/2023]
Abstract
Puberty is a key developmental milestone that marks an individual's maturation in several ways including, but not limited to, reproductive maturation, changes in behaviors and neural organization. The timing at which puberty occurs is variable both within individuals of the same species and between species. These variations can be aligned with ecological cues that delay or suppress puberty. Naked mole-rats are colony-living rodents where reproduction is restricted to a few animals; all other animals are pubertally-suppressed. Animals removed from suppressive colony cues can reproductively mature, presenting the unique opportunity to study adult-onset puberty. Recently, we found that RFRP-3 administration sustains pubertal delay in naked mole-rats removed from colony. In this review, we explore what is known about regulators that control puberty onset, the role of stress/social status in pubertal timing, the status of knowledge of pubertal suppression in naked mole-rats and what comes next.
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Affiliation(s)
| | | | - Melissa M Holmes
- Department of Cell and Systems Biology, University of Toronto, Canada; Department of Psychology, University of Toronto Mississauga, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Canada
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Thomas FSK, Higuchi Y, Ogawa S, Soga T, Parhar IS. Acute social defeat stress upregulates gonadotrophin inhibitory hormone and its receptor but not corticotropin-releasing hormone and ACTH in the Male Nile Tilapia (Oreochromis niloticus). Peptides 2021; 138:170504. [PMID: 33539873 DOI: 10.1016/j.peptides.2021.170504] [Citation(s) in RCA: 5] [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: 12/04/2020] [Revised: 01/14/2021] [Accepted: 01/19/2021] [Indexed: 12/30/2022]
Abstract
Stress impairs the hypothalamic-pituitary-gonadal (HPG) axis, probably through its influence on the hypothalamic-pituitary-adrenal (= interrenals in the teleost, HPI) axis leading to reproductive failures. In this study, we investigated the response of hypothalamic neuropeptides, gonadotropin-inhibitory hormone (GnIH), a component of the HPG axis, and corticotropin-releasing hormone (CRH) a component of the HPI axis, to acute social defeat stress in the socially hierarchical male Nile tilapia (Oreochromis niloticus). Localization of GnIH cell bodies, GnIH neuronal processes, and numbers of GnIH cells in the brain during acute social defeat stress was studied using immunohistochemistry. Furthermore, mRNA levels of GnIH and CRH in the brain together with GnIH receptor, gpr147, and adrenocorticotropic hormone (ACTH) in the pituitary were quantified in control and socially defeated fish. Our results show, the number of GnIH-immunoreactive cell bodies and GnIH mRNA levels in the brain and the levels of gpr147 mRNA in the pituitary significantly increased in socially defeated fish. However, CRH and ACTH mRNA levels did not change during social defeat stress. Further, we found glucocorticoid type 2b receptor mRNA in laser captured immunostained GnIH cells. These results show that acute social defeat stress activates GnIH biosynthesis through glucocorticoid receptors type 2b signalling but does not change the CRH and ACTH mRNA expression in the tilapia, which could lead to temporary reproductive dysfunction.
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Affiliation(s)
- Felix Suresh Kevin Thomas
- Brain Research Institute, Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia
| | - Yuki Higuchi
- Brain Research Institute, Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia
| | - Satoshi Ogawa
- Brain Research Institute, Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia
| | - Tomoko Soga
- Brain Research Institute, Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia.
| | - Ishwar S Parhar
- Brain Research Institute, Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia
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Ibos KE, Bodnár É, Bagosi Z, Bozsó Z, Tóth G, Szabó G, Csabafi K. Kisspeptin-8 Induces Anxiety-Like Behavior and Hypolocomotion by Activating the HPA Axis and Increasing GABA Release in the Nucleus Accumbens in Rats. Biomedicines 2021; 9:112. [PMID: 33503835 PMCID: PMC7911394 DOI: 10.3390/biomedicines9020112] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/18/2021] [Accepted: 01/22/2021] [Indexed: 12/11/2022] Open
Abstract
Kisspeptins (Kp) are RF-amide neuropeptide regulators of the reproductive axis that also influence anxiety, locomotion, and metabolism. We aimed to investigate the effects of intracerebroventricular Kp-8 (an N-terminally truncated octapeptide) treatment in Wistar rats. Elevated plus maze (EPM), computerized open field (OF), and marble burying (MB) tests were performed for the assessment of behavior. Serum LH and corticosterone levels were determined to assess kisspeptin1 receptor (Kiss1r) activation and hypothalamic-pituitary-adrenal axis (HPA) stimulation, respectively. GABA release from the nucleus accumbens (NAc) and dopamine release from the ventral tegmental area (VTA) and NAc were measured via ex vivo superfusion. Kp-8 decreased open arm time and entries in EPM, and also raised corticosterone concentration, pointing to an anxiogenic effect. Moreover, the decrease in arm entries in EPM, the delayed increase in immobility accompanied by reduced ambulatory activity in OF, and the reduction in interactions with marbles show that Kp-8 suppressed exploratory and spontaneous locomotion. The increase in GABA release from the NAc might be in the background of hypolocomotion by inhibiting the VTA-NAc dopaminergic circuitry. As Kp-8 raised LH concentration, it could activate Kiss1r and stimulate the reproductive axis. As Kiss1r is associated with hyperlocomotion, it is more likely that neuropeptide FF receptor activation is involved in the suppression of locomotor activity.
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Affiliation(s)
- Katalin Eszter Ibos
- Department of Pathophysiology, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (É.B.); (Z.B.); (K.C.)
| | - Éva Bodnár
- Department of Pathophysiology, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (É.B.); (Z.B.); (K.C.)
| | - Zsolt Bagosi
- Department of Pathophysiology, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (É.B.); (Z.B.); (K.C.)
| | - Zsolt Bozsó
- Department of Medical Chemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (Z.B.); (G.T.)
| | - Gábor Tóth
- Department of Medical Chemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (Z.B.); (G.T.)
| | - Gyula Szabó
- Office of International Affairs, Budapest Campus, McDaniel College, H-1071 Budapest, Hungary;
| | - Krisztina Csabafi
- Department of Pathophysiology, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (É.B.); (Z.B.); (K.C.)
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11
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Bédécarrats GY, Hanlon C, Tsutsui K. Gonadotropin Inhibitory Hormone and Its Receptor: Potential Key to the Integration and Coordination of Metabolic Status and Reproduction. Front Endocrinol (Lausanne) 2021; 12:781543. [PMID: 35095760 PMCID: PMC8792613 DOI: 10.3389/fendo.2021.781543] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/02/2021] [Indexed: 12/18/2022] Open
Abstract
Since its discovery as a novel gonadotropin inhibitory peptide in 2000, the central and peripheral roles played by gonadotropin-inhibiting hormone (GnIH) have been significantly expanded. This is highlighted by the wide distribution of its receptor (GnIH-R) within the brain and throughout multiple peripheral organs and tissues. Furthermore, as GnIH is part of the wider RF-amide peptides family, many orthologues have been characterized across vertebrate species, and due to the promiscuity between ligands and receptors within this family, confusion over the nomenclature and function has arisen. In this review, we intend to first clarify the nomenclature, prevalence, and distribution of the GnIH-Rs, and by reviewing specific localization and ligand availability, we propose an integrative role for GnIH in the coordination of reproductive and metabolic processes. Specifically, we propose that GnIH participates in the central regulation of feed intake while modulating the impact of thyroid hormones and the stress axis to allow active reproduction to proceed depending on the availability of resources. Furthermore, beyond the central nervous system, we also propose a peripheral role for GnIH in the control of glucose and lipid metabolism at the level of the liver, pancreas, and adipose tissue. Taken together, evidence from the literature strongly suggests that, in fact, the inhibitory effect of GnIH on the reproductive axis is based on the integration of environmental cues and internal metabolic status.
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Affiliation(s)
- Grégoy Y. Bédécarrats
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
- *Correspondence: Grégoy Y. Bédécarrats,
| | - Charlene Hanlon
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Kazuyoshi Tsutsui
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
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12
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Teo CH, Phon B, Parhar I. The Role of GnIH in Biological Rhythms and Social Behaviors. Front Endocrinol (Lausanne) 2021; 12:728862. [PMID: 34566893 PMCID: PMC8461181 DOI: 10.3389/fendo.2021.728862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/23/2021] [Indexed: 12/30/2022] Open
Abstract
Gonadotropin-inhibitory hormone (GnIH) was first discovered in the Japanese quail, and peptides with a C-terminal LPXRFamide sequence, the signature protein structure defining GnIH orthologs, are well conserved across vertebrate species, including fish, reptiles, amphibians, avians, and mammals. In the mammalian brain, three RFamide-related proteins (RFRP-1, RFRP-2, RFRP-3 = GnIH) have been identified as orthologs to the avian GnIH. GnIH is found primarily in the hypothalamus of all vertebrate species, while its receptors are distributed throughout the brain including the hypothalamus and the pituitary. The primary role of GnIH as an inhibitor of gonadotropin-releasing hormone (GnRH) and pituitary gonadotropin release is well conserved in mammalian and non-mammalian species. Circadian rhythmicity of GnIH, regulated by light and seasons, can influence reproductive activity, mating behavior, aggressive behavior, and feeding behavior. There is a potential link between circadian rhythms of GnIH, anxiety-like behavior, sleep, stress, and infertility. Therefore, in this review, we highlight the functions of GnIH in biological rhythms, social behaviors, and reproductive and non-reproductive activities across a variety of mammalian and non-mammalian vertebrate species.
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13
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Coen CW, Bennett NC, Holmes MM, Faulkes CG. Neuropeptidergic and Neuroendocrine Systems Underlying Eusociality and the Concomitant Social Regulation of Reproduction in Naked Mole-Rats: A Comparative Approach. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1319:59-103. [PMID: 34424513 DOI: 10.1007/978-3-030-65943-1_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The African mole-rat family (Bathyergidae) includes the first mammalian species identified as eusocial: naked mole-rats. Comparative studies of eusocial and solitary mole-rat species have identified differences in neuropeptidergic systems that may underlie the phenomenon of eusociality. These differences are found in the oxytocin, vasopressin and corticotrophin-releasing factor (CRF) systems within the nucleus accumbens, amygdala, bed nucleus of the stria terminalis and lateral septal nucleus. As a corollary of their eusociality, most naked mole-rats remain pre-pubertal throughout life because of the presence of the colony's only reproductive female, the queen. To elucidate the neuroendocrine mechanisms that mediate this social regulation of reproduction, research on the hypothalamo-pituitary-gonadal axis in naked mole-rats has identified differences between the many individuals that are reproductively suppressed and the few that are reproductively mature: the queen and her male consorts. These differences involve gonadal steroids, gonadotrophin-releasing hormone-1 (GnRH-1), kisspeptin, gonadotrophin-inhibitory hormone/RFamide-related peptide-3 (GnIH/RFRP-3) and prolactin. The comparative findings in eusocial and solitary mole-rat species are assessed with reference to a broad range of studies on other mammals.
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Affiliation(s)
- Clive W Coen
- Reproductive Neurobiology, Division of Women's Health, Faculty of Life Sciences & Medicine, King's College London, London, UK.
| | - Nigel C Bennett
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Melissa M Holmes
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada.,Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, Canada.,Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| | - Christopher G Faulkes
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
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14
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Rahdar P, Khazali H. Rfamide-related peptide-3 suppresses the substance P-induced promotion of the reproductive performance in female rats modulating hypothalamic Kisspeptin expression. Exp Brain Res 2020; 238:2457-2467. [PMID: 32783107 DOI: 10.1007/s00221-020-05860-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/22/2020] [Indexed: 11/28/2022]
Abstract
RFamide-related peptide-3 (RFRP-3) has been postulated as the suppressor of the reproductive axis at hypothalamic, pituitary and gonadal levels. Considering the hypothalamic level, RFRP-3 can suppress the activity of gonadotropin-releasing hormone (GnRH) neurons and their upstream neuronal stimulator, namely; the kisspeptin neurons. The effects of the RFRP-3 on the other regulators of GnRH neurons, however, are not completely investigated. Furthermore, substance P (SP) has been known as one of the coordinators of GnRH/ luteinizing hormone (LH) and the kisspeptin/G protein-coupled receptor 54 (GPR54) systems. The present study was aimed at investigating the impacts of RFRP-3 on the effects of SP on the reproductive performance in ovariectomized female rats. After intracerebroventricular (ICV) cannulation, the rats were subjected to the ICV injection of either SP or RFRP-3 and simultaneous injection of them and their selective antagonists. Blood and hypothalamic samplings and also sexual behavioral test were carried out on two main groups of rats. The analyses of the results of LH radioimmunoassay, gene expression assay for hypothalamic Gnrh1, Kisspeptin and Gpr54 accompanied by sexual behavioral examination revealed that the SP administration promotes reproductive behavior and GnRH/LH system and upregulates Kisspeptin expression. The RFRP-3 administration suppressed reproductive behavior, GnRH / LH system and Kisspeptin expression; however, the simultaneous injection of SP and RFRP-3 was devoid of significant alterations in the assessed parameters. The results showed that RFRP-3 can modulates the impacts of SP on the reproductive performance in ovariectomized female rats in part through adjusting Kisspeptin expression.
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Affiliation(s)
- Parastoo Rahdar
- Department of Animal Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
| | - Homayoun Khazali
- Department of Animal Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.
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15
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Moosadoost Y, Zendehdel M, Khodadadi M. The Effect of RFamide-Related Peptide-3 (RFRP-3 or NPVF) on Food Intake in Neonatal Chickens: The Role of MC3/MC4 and CRF1/CRF2 Receptors. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10081-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Poissenot K, Anger K, Constantin P, Cornilleau F, Lomet D, Tsutsui K, Dardente H, Calandreau L, Beltramo M. Brain mapping of the gonadotropin-inhibitory hormone-related peptide 2 with a novel antibody suggests a connection with emotional reactivity in the Japanese quail (Coturnix japonica, Temminck & Schlegel, 1849). J Comp Neurol 2019; 527:1872-1884. [PMID: 30734308 DOI: 10.1002/cne.24659] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 01/22/2019] [Accepted: 01/25/2019] [Indexed: 12/23/2022]
Abstract
Gonadotropin-inhibitory hormone (GnIH) is a neuropeptide first discovered in the quail brain that is involved in the control of reproductive physiology and behaviors, and stress response. GnIH gene encodes a second peptide, GnIH-related peptide-2 (RP2), the distribution and function of which remain unknown. We therefore studied GnIH-RP2 distribution by immunohistochemistry using a novel antibody capable of discriminating between GnIH and GnIH-RP2. The overall distribution of GnIH-RP2 is similar to that of GnIH. The vast majority of labeled neurons is located in the paraventricular nucleus (PVN) of the hypothalamus. Labeling of fibers is conspicuous in the diencephalon, but present also in the mesencephalon and telencephalon. Several regions involved in the control of reproduction and stress response (the PVN, septum, bed nucleus of the stria terminalis and nucleus commissura pallii) showed a dense network of immunolabeled fibers. To investigate the potential function of GnIH-RP2 we compared its expression in two quail lines genetically selected for divergence in their emotional reactivity. A quantitative analysis in the above-mentioned brain regions showed that the density of fibers was similar in the two lines. However, the number of GnIH-RP2 labeled neurons was higher in the median portion of the PVN in birds with higher emotional reactivity. These results point to a possible involvement of GnRH-RP2 in modulating stress response and/or emotional reactivity.
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Affiliation(s)
- Kevin Poissenot
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Karine Anger
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Paul Constantin
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Fabien Cornilleau
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Didier Lomet
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
| | - Hugues Dardente
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Ludovic Calandreau
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
| | - Massimiliano Beltramo
- INRA, UMR85 Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, Université de Tours, IFCE, Nouzilly, France
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The Impact of Morphine on Reproductive Activity in Male Rats Is Regulated by Rf-Amid-Related Peptide-3 and Substance P Adjusting Hypothalamic Kisspeptin Expression. J Mol Neurosci 2019; 69:456-469. [DOI: 10.1007/s12031-019-01375-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/28/2019] [Indexed: 02/08/2023]
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18
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Ubuka T, Tsutsui K. Reproductive neuroendocrinology of mammalian gonadotropin-inhibitory hormone. Reprod Med Biol 2019; 18:225-233. [PMID: 31312100 PMCID: PMC6613023 DOI: 10.1002/rmb2.12272] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/25/2019] [Accepted: 04/05/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Gonadotropin-inhibitory hormone (GnIH) was discovered in the Japanese quail brain in 2000 as a hypothalamic neuropeptide that suppresses luteinizing hormone release from cultured quail anterior pituitary. METHODS The authors investigated the existence of mammalian orthologous peptides to GnIH and their physiological functions in the following 19 years of research. MAIN FINDINGS Mammals have orthologous peptide to GnIH, often described RFamide-related peptide, expressed in the hypothalamus and gonads. Mammalian GnIH may also suppress gonadotropin synthesis and release by suppressing gonadotropin-releasing hormone (GnRH) synthesis and release in addition to directly suppressing gonadotropin synthesis and release from the pituitary. Mammalian GnIH may also suppress kisspeptin, a stimulator of GnRH, release. Mammalian GnIH is also expressed in the testis and ovary and suppresses gametogenesis and sex steroid production acting in an autocrine/paracrine manner. Thus, mammalian GnIH may act at all levels of the hypothalamic-pituitary-gonadal axis to suppress reproduction. GnIH may be involved in the regulation of puberty, estrous or menstrual cycle, seasonal reproduction, and stress responses. CONCLUSION Studies suggest that mammalian GnIH is an important neuroendocrine suppressor of reproduction in mammals.
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Affiliation(s)
- Takayoshi Ubuka
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life ScienceWaseda UniversityShinjukuJapan
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life ScienceWaseda UniversityShinjukuJapan
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19
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Son YL, Ubuka T, Tsutsui K. Molecular Mechanisms of Gonadotropin-Inhibitory Hormone (GnIH) Actions in Target Cells and Regulation of GnIH Expression. Front Endocrinol (Lausanne) 2019; 10:110. [PMID: 30858828 PMCID: PMC6397841 DOI: 10.3389/fendo.2019.00110] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 02/06/2019] [Indexed: 11/13/2022] Open
Abstract
Since gonadotropin-inhibitory hormone (GnIH) was discovered in 2000 as the first hypothalamic neuropeptide that actively inhibits gonadotropin release, researches conducted for the last 18 years have demonstrated that GnIH acts as a pronounced negative regulator of reproduction. Inhibitory effect of GnIH on reproduction is mainly accomplished at hypothalamic-pituitary levels; gonadotropin-releasing hormone (GnRH) neurons and gonadotropes are major targets of GnIH action based on the morphological interaction with GnIH neuronal fibers and the distribution of GnIH receptor. Here, we review molecular studies mainly focusing on the signal transduction pathway of GnIH in target cells, GnRH neurons, and gonadotropes. The use of well-defined cellular model systems allows the mechanistic study of signaling pathway occurring in target cells by demonstrating the direct cause-and-effect relationship. The insights gained through studying molecular mechanism of GnIH action contribute to deeper understanding of the mechanism of how GnIH communicates with other neuronal signaling systems to control our reproductive function. Reproductive axis closely interacts with other endocrine systems, thus GnIH expression levels would be changed by adrenal and thyroid status. We also briefly review molecular studies investigating the regulatory mechanisms of GnIH expression to understand the role of GnIH as a mediator between adrenal, thyroid and gonadal axes.
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Affiliation(s)
- You Lee Son
- Laboratory of Photobiology, Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
- *Correspondence: You Lee Son
| | - Takayoshi Ubuka
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
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20
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Tsutsui K, Ubuka T. How to Contribute to the Progress of Neuroendocrinology: Discovery of GnIH and Progress of GnIH Research. Front Endocrinol (Lausanne) 2018; 9:662. [PMID: 30483217 PMCID: PMC6241250 DOI: 10.3389/fendo.2018.00662] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 10/23/2018] [Indexed: 01/14/2023] Open
Abstract
It is essential to discover novel neuropeptides that regulate the functions of pituitary, brain and peripheral secretory glands for the progress of neuroendocrinology. Gonadotropin-releasing hormone (GnRH), a hypothalamic neuropeptide stimulating gonadotropin release was isolated and its structure was determined by Schally's and Guillemin's groups at the beginning of the 1970s. It was subsequently shown that GnRH is highly conserved among vertebrates. GnRH was assumed the sole hypothalamic neuropeptide that regulates gonadotropin release in vertebrates based on extensive studies of GnRH over the following three decades. However, in 2000, Tsutsui's group isolated and determined the structure of a novel hypothalamic neuropeptide, which inhibits gonadotropin release, in quail, an avian species, and named it gonadotropin-inhibitory hormone (GnIH). Following studies by Tsutsui's group demonstrated that GnIH is highly conserved among vertebrates, from humans to agnathans, and acts as a key neuropeptide inhibiting reproduction. Intensive research on GnIH demonstrated that GnIH inhibits gonadotropin synthesis and release by acting on gonadotropes and GnRH neurons via GPR147 in birds and mammals. Fish GnIH also regulates gonadotropin release according to its reproductive condition, indicating the conserved role of GnIH in the regulation of the hypothalamic-pituitary-gonadal (HPG) axis in vertebrates. Therefore, we can now say that GnRH is not the only hypothalamic neuropeptide controlling vertebrate reproduction. In addition, recent studies by Tsutsui's group demonstrated that GnIH acts in the brain to regulate behaviors, including reproductive behavior. The 18 years of GnIH research with leading laboratories in the world have significantly advanced our knowledge of the neuroendocrine control mechanism of reproductive physiology and behavior as well as interactions of the HPG, hypothalamic-pituitary-adrenal and hypothalamic-pituitary-thyroid axes. This review describes how GnIH was discovered and GnIH research progressed in this new research era of reproductive neuroendocrinology.
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Affiliation(s)
- Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
| | - Takayoshi Ubuka
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Tokyo, Japan
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21
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Ubuka T, Tsutsui K. Comparative and Evolutionary Aspects of Gonadotropin-Inhibitory Hormone and FMRFamide-Like Peptide Systems. Front Neurosci 2018; 12:747. [PMID: 30405335 PMCID: PMC6200920 DOI: 10.3389/fnins.2018.00747] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 09/28/2018] [Indexed: 11/13/2022] Open
Abstract
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that was found in the brain of Japanese quail when investigating the existence of RFamide peptides in birds. GnIH was named because it decreased gonadotropin release from cultured anterior pituitary, which was located in the hypothalamo-hypophysial system. GnIH and GnIH precursor gene related peptides have a characteristic C-terminal LPXRFamide (X = L or Q) motif that is conserved in jawed vertebrates. Orthologous peptides to GnIH are also named RFamide related peptide or LPXRFamide peptide from their structure. A G-protein coupled receptor GPR147 is the primary receptor for GnIH. Similarity-based clustering of neuropeptide precursors in metazoan species indicates that GnIH precursor of vertebrates is evolutionarily related to FMRFamide precursor of mollusk and nematode. FMRFamide peptide is the first RFamide peptide that was identified from the ganglia of the venus clam. In order to infer the evolutionary history of the GnIH-GnIH receptor system we investigate the structural similarities between GnIH and its receptor and well-studied nematode Caenorhabditis elegans (C. elegans) FMRFamide-like peptides (FLPs) and their receptors. We also compare the functions of FLPs of nematode with GnIH of chordates. A multiple sequence alignment and phylogenetic analyses of GnIH, neuropeptide FF (NPFF), a paralogous peptide of GnIH, and FLP precursors have shown that GnIH and NPFF precursors belong to different clades and some FLP precursors have structural similarities to either precursor. The peptide coding regions of FLP precursors in the same clade align well with those of GnIH or NPFF precursors. Alignment of GnIH (LPXRFa) peptides of chordates and FLPs of C. elegans grouped the peptides into five groups according to the last C-terminal amino acid sequences, which were MRFa, LRFa, VRFa, IRFa, and PQRFa. Phylogenetic analysis of receptors suggested that GPR147 has evolutionary relationships with FLP receptors, which regulate reproduction, aggression, locomotion, and feeding. GnIH and some FLPs mediate the effect of stress on reproduction and behavior, which may also be a conserved property of these peptide systems. Future studies are needed to investigate the mechanism of how neuropeptide precursor genes are mutated to evolve new neuropeptides and their inheritance.
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Affiliation(s)
- Takayoshi Ubuka
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Japan
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Japan
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22
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Ubuka T, Parhar IS, Tsutsui K. Gonadotropin-inhibitory hormone mediates behavioral stress responses. Gen Comp Endocrinol 2018; 265:202-206. [PMID: 29510150 DOI: 10.1016/j.ygcen.2018.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 02/07/2018] [Accepted: 03/02/2018] [Indexed: 10/17/2022]
Abstract
Gonadotropin-inhibitory hormone (GnIH) is an inhibitor of the hypothalamic-pituitary-gonadal (HPG) axis. GnIH is also called RFamide-related peptide (RFRP) as GnIH peptides have a characteristic C-terminal LPXRFiamide (X = L or Q) sequence. GnIH is thought to be the mediator of stress by negatively regulating the HPG axis as various stressors increase GnIH mRNA, GnIH peptide or GnIH neuronal activity. On the other hand, GnIH may also mediate behavioral stress responses as GnIH neuronal fibers and GnIH receptors are widely located in the limbic system of telencephalon, diencephalon and midbrain area. Previous studies have shown that intracerebroventricular (i.c.v.) administration of GnIH (RFRP) blocks morphine-induced analgesia in hot plate and formalin injection tests in rats suggesting that GnIH increases sensitivity to pain. GnIH (RFRP) also increases anxiety-like behavior in rats. RNA interference of GnIH gene (GnIH RNAi) increases locomotor activity of white-crowned sparrow and Japanese quail and i.c.v. administration of GnIH decreases GnIH RNAi induced locomotor activity. It was further shown that i.c.v. administration of GnIH (RFRP) decreases aggressive behavior in male quail and sexual behavior in male rats, female white-crowned sparrow and female hamsters. These results suggest that GnIH decreases threat to homeostasis of the organism by increasing pain sensitivity, anxiety and decreasing locomotor activity, aggressive behavior and sexual behavior. GnIH may also mediate the effect of stress on behavior.
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Affiliation(s)
- Takayoshi Ubuka
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Tokyo 162-8480, Japan; Brain Research Institute Monash Sunway (BRIMS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia.
| | - Ishwar S Parhar
- Brain Research Institute Monash Sunway (BRIMS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Tokyo 162-8480, Japan
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Kriegsfeld LJ, Jennings KJ, Bentley GE, Tsutsui K. Gonadotrophin-inhibitory hormone and its mammalian orthologue RFamide-related peptide-3: Discovery and functional implications for reproduction and stress. J Neuroendocrinol 2018; 30:e12597. [PMID: 29624758 PMCID: PMC6263162 DOI: 10.1111/jne.12597] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 03/26/2018] [Accepted: 03/28/2018] [Indexed: 02/06/2023]
Abstract
At the turn of the millennium, a neuropeptide with pronounced inhibitory actions on avian pituitary gonadotrophin secretion was identified and named gonadotrophin-inhibitory hormone (GnIH). Across bird species, GnIH acts at the level of the pituitary and the gonadotrophin-releasing hormone (GnRH) neuronal system to inhibit reproduction. Subsequent to this initial discovery, orthologues of GnIH have been identified and characterised across a broad range of species. In many vertebrates, the actions of GnIH and its orthologues serve functional roles analogous to those seen in birds. In other cases, GnIH and its orthologues exhibit more diverse actions dependent on sex, species, season and reproductive condition. The present review highlights the discovery and functional implications of GnIH across species, focusing on research domains in which the significance of this neuropeptide has been explored most.
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Affiliation(s)
- Lance J. Kriegsfeld
- Department of Psychology, University of California, Berkeley, California 94720, USA
- The Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, USA
- Corresponding Author: Lance J. Kriegsfeld, Ph.D. Neurobiology Laboratory, Department of Psychology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, California 94720-1650, USA, Phone: (510) 642-5148; Fax: (510) 642-5293;
| | - Kimberly J. Jennings
- Department of Psychology, University of California, Berkeley, California 94720, USA
| | - George E. Bentley
- The Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, USA
- Department of Integrative Biology, University of California, Berkeley, California 94720, USA
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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Ullah R, Batool A, Wazir M, Naz R, Rahman TU, Wahab F, Shahab M, Fu J. Gonadotropin inhibitory hormone and RF9 stimulate hypothalamic-pituitary-adrenal axis in adult male rhesus monkeys. Neuropeptides 2017; 66:1-7. [PMID: 28757099 DOI: 10.1016/j.npep.2017.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 07/19/2017] [Accepted: 07/23/2017] [Indexed: 12/17/2022]
Abstract
Stress activates gonadotropin inhibitory hormone (GnIH), hypothalamic-pituitary-adrenal axis (HPA-axis) and represses hypothalamic-pituitary-gonadal axis (HPG-axis) but RF9 administration relieves stress-induced repression of the HPG-axis. Importantly, it was not known whether GnIH signaling and RF9 synthetic peptide modulate the HPA axis. To assess this, mammalian orthologs of GnIH (RFRP-1 and RFRP-3) and RF9 were administered to intact adult male rhesus monkeys. RFRP-1 (125μg/animal), RFRP-3 (250μg/animal) and RF9 (0.1mg/kg BW) were intravenously (iv) injected into normal fed (n=4) monkeys. Additionally, a single bolus iv injection of RF9 (0.1mg/kg BW) was also administered to 48h fasted monkeys (n=4) to check the effects of RF9 signaling on an activated HPA-axis. Serial blood samples were collected, centrifuged and the obtained plasma was used for the analysis of cortisol by specific enzyme immunoassay. RFRP-1 treatment significantly increased cortisol levels while RFRP-3 increased the plasma cortisol, but the effect was non-significant. RF9 treatment significantly increased cortisol levels in normal fed animals. In contrast, RF9 injection did not significantly alter circulating cortisol in fasted monkeys. In conclusion, our results suggest stimulatory action of RFRPs and RF9 on the HPA axis in the adult male monkeys. However, the mechanism and site of action of RFRP-1 and RF9 along the HPA-axis is still unknown. Therefore, further studies are needed to decipher the mechanism and site of action of RFRPs and RF9 on the HPA axis in primates.
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Affiliation(s)
- Rahim Ullah
- Department of Endocrinology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310051, China; Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Aalia Batool
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; The State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China
| | - Madiha Wazir
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Rabia Naz
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Tanzil Ur Rahman
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; Department of Pathology and Pathophysiology, Key Laboratory of Reproductive Genetics, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Fazal Wahab
- Platform Degenerative Diseases, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, D-37077 Göttingen, Germany
| | - Muhammad Shahab
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
| | - Junfen Fu
- Department of Endocrinology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310051, China.
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Schneider JE, Benton NA, Russo KA, Klingerman CM, Williams WP, Simberlund J, Abdulhay A, Brozek JM, Kriegsfeld LJ. RFamide-related Peptide-3 and the Trade-off between Reproductive and Ingestive Behavior. Integr Comp Biol 2017; 57:1225-1239. [PMID: 28985338 PMCID: PMC5886337 DOI: 10.1093/icb/icx097] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Ingestive and sex behaviors are important for individual survival and reproductive success, but when environmental energy availability is limited, individuals of many different species make a trade-off, forfeiting sex for ingestive behavior. For example, food-deprived female Syrian hamsters (Mesocricetus auratus) forego vaginal scent marking and lordosis (sex behaviors) in favor of foraging, hoarding, and eating food (ingestive behavior). Reproductive processes tend to be energetically costly, and individual survival requires homeostasis in metabolic energy. Thus, during energetic challenges, the chances of survival are enhanced by decreasing the energy expended on reproductive processes. The entire hypothalamic-pituitary-gonadal (HPG) system is inhibited by severe energetic challenges, but comparatively little is known about the effects of mild energetic challenges. We hypothesized that (1) a trade-off is made between sex and ingestive behavior even when the level of food restriction is insufficient to inhibit the HPG system; (2) mild energetic challenges force a trade-off between appetitive ingestive and sex behaviors, but not consummatory versions of the same behaviors; and (3) the trade-off is orchestrated by ovarian steroid modulation of RFamide-related peptide 3 (RFRP-3). In other species, RFRP-3, an ortholog of avian gonadotropin-inhibitory hormone, is implicated in control of behavior in response to energetic challenges and stressful stimuli. In support of our three hypotheses, there is a "dose-response" effect of food restriction and re-feeding on the activation of RFRP-3-immunoreactive cells in the dorsomedial hypothalamus and on appetitive behaviors (food hoarding and sexual motivation), but not on consummatory behaviors (food intake and lordosis), with no significant effect on circulating levels of estradiol or progesterone. The effect of food restriction on the activation of RFRP-3 cells is modulated at the time of estrus in gonadally-intact females and in ovariectomized females treated with progesterone alone or with estradiol plus progesterone. Intracerebral treatment with RFRP-3 results in significant decreases in sexual motivation and results in significant but small increases in food hoarding in hamsters fed ad libitum. These and other results are consistent with the idea that ovarian steroids and RFRP-3 are part of a system that orchestrates trade-offs in appetitive behaviors in environments where energy availability fluctuates.
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Affiliation(s)
- Jill E Schneider
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | - Noah A Benton
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | - Kim A Russo
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA
| | - Candice M Klingerman
- Department of Biological and Allied Health Sciences, Bloomsburg University, Bloomsburg, PA 17815, USA
| | - Wilbur P Williams
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA
| | - Jessica Simberlund
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | - Amir Abdulhay
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | - Jeremy M Brozek
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | - Lance J Kriegsfeld
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA
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Dave A, Krishna A, Tsutsui K. Direct effects of RFRP-1, a mammalian GnIH ortholog, on ovarian activities of the cyclic mouse. Gen Comp Endocrinol 2017; 252:193-199. [PMID: 28658602 DOI: 10.1016/j.ygcen.2017.06.024] [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: 01/17/2017] [Revised: 05/30/2017] [Accepted: 06/24/2017] [Indexed: 12/21/2022]
Abstract
Arg(R)-Phe(F)-amide related peptide-1 (RFRP-1) and -3 (RFRP-3) are known as mammalian orthologs of gonadotropin-inhibitory hormone (GnIH). In mammals, these RFRPs are expressed not only in the hypothalamus and but also in gonads. Inhibitory roles of the hypothalamic and gonadal RFRP-3 in reproduction have been documented in mammals. However, functional roles of the hypothalamic and gonadal RFRP-1 in reproduction are still unclear in mammals. Therefore, in vitro studies were conducted to elucidate the direct effect of RFRP-1, a mammalian GnIH ortholog, on ovarian activities, such as steroidogenesis, apoptosis, cell proliferation and metabolism in the cyclic mouse. The ovaries collected from the proestrus mice were cultured in vitro with different doses (Control, 1ng/ml, 10ng/ml and 100ng/ml) of RFRP-1 for 24h at 37°C. A significant dose-dependent increase in estradiol release from the ovary was detected after the treatment of RFRP-1. Therefore, changes in the ovarian activities, such as steroidogenic markers (luteinizing hormone receptors; LH-R and 3β-hydroxysteroid dehydrogenase; 3β-HSD), apoptotic markers [Poly(ADP-ribose) polymerase-1; PARP-1 and cysteine-aspartic protease; caspase-3], a cell proliferation marker (proliferating cell nuclear antigen; PCNA) and metabolic markers (GLUT-4; glucose uptake) were assessed by the treatment of RFRP-1 in the proestrus ovary. The densitometry analysis showed the treatment of RFRP-1 significantly increased the expressions of LH-R and 3β-HSD, steroidogenic markers. In contrast, the expressions of PCNA, a cell proliferation maker; PARP-1 and caspase-3, apoptotic markers were significantly decreased. Interestingly, RFRP-1 treatment further increases significantly glucose uptake and GLUT-4 receptor expression. These findings indicate that RFRP-1 possesses a stimulatory effect on ovarian steroidogenesis in the proestrus mouse. This is the first evidence showing the direct action of RFRP-1 on steroidogenesis in any vertebrate. In addition, RFRP-1 may also act directly on ovarian folliculogenesis as an inhibitory factor.
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Affiliation(s)
- Anushree Dave
- Department of Zoology, Institute of Sciences, Banaras Hindu University, Varanasi 221 005, India
| | - Amitabh Krishna
- Department of Zoology, Institute of Sciences, Banaras Hindu University, Varanasi 221 005, India.
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, Shinjukuku, Tokyo, Japan
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Benton NA, Russo KA, Brozek JM, Andrews RJ, Kim VJ, Kriegsfeld LJ, Schneider JE. Food restriction-induced changes in motivation differ with stages of the estrous cycle and are closely linked to RFamide-related peptide-3 but not kisspeptin in Syrian hamsters. Physiol Behav 2017. [PMID: 28624479 DOI: 10.1016/j.physbeh.2017.06.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We tested the hypothesis that the effects of food restriction on behavioral motivation are mediated by one or both of the RFamide peptides, RFamide-related peptide-3 (RFRP-3) and kisspeptin (Kp) in female Syrian hamsters (Mesocricetus auratus). Female hamsters fed ad libitum and given a choice between food and adult male hamsters are highly motivated to visit males instead of food on all four days of the estrous cycle, but after 8days of mild food restriction (75% of ad libitum intake) they shift their preference toward food every day of the estrous cycle until the day of estrus, when they shift their preference back toward the males. In support of a role for RFRP-3 in these behavioral changes, the preference for food and the activation of RFRP-3-immunoreactive (Ir) cells in the dorsomedial hypothalamus (DMH) showed the same estrous cycle pattern in food-restricted females, but no association was observed between behavior and the activation of Kp cells in the hypothalamic arcuate nucleus or preoptic area. Next, we tested the hypothesis that food-restriction-induced activation of RFRP-3-Ir cells is modulated by high levels of ovarian steroids at the time of estrus. In support of this idea, on nonestrous days, mild food restriction increased activation of RFRP-3-Ir cells, but failed to do so on the day of estrus even though this level of food restriction did not significantly decrease circulating concentrations of estradiol or progesterone. Furthermore, in ovariectomized females, food-restriction-induced increases in activation of RFRP-3-Ir cells were blocked by systemic treatment with progesterone alone, estradiol plus progesterone, but not estradiol alone. Central infusion with RFRP-3 in ad libitum-fed females significantly decreased sexual motivation and produced significant increases in 90-minute food hoarding, in support of the hypothesis that elevated central levels of RFRP-3 are sufficient to create the shift in behavioral motivation in females fed ad libitum. Together, these results are consistent with the hypothesis that high levels of ingestive motivation are promoted during the nonfertile phase of the estrous cycle by elevated activation of RFRP-3-Ir cells, and RFRP-3-Ir cellular activation is modulated by ovarian steroids around the time of estrus, thereby diverting attention away from food and increasing sexual motivation.
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Affiliation(s)
- Noah A Benton
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, United States
| | - Kim A Russo
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, United States
| | - Jeremy M Brozek
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, United States
| | - Ryan J Andrews
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, United States
| | - Veronica J Kim
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, United States
| | - Lance J Kriegsfeld
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, United States
| | - Jill E Schneider
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, United States.
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Kovács A, László K, Zagoracz O, Ollmann T, Péczely L, Gálosi R, Lénárd L. Effects of RFamide-related peptide-1 (RFRP-1) microinjections into the central nucleus of amygdala on passive avoidance learning in rats. Neuropeptides 2017; 62:81-86. [PMID: 27993374 DOI: 10.1016/j.npep.2016.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/31/2016] [Accepted: 12/11/2016] [Indexed: 11/16/2022]
Abstract
The amygdaloid body (AMY) plays an important role in memory, learning and reward-related processes. RFRP-1 immunoreactive fibers and NPFF receptors were identified in the AMY, and previously we verified that RFRP-1 infused into the central nucleus of AMY (CeA) induced place preference. The aim of the present study was to examine the possible effects of RFRP-1 in the CeA on passive avoidance learning. Male Wistar rats were examined in two-compartment passive avoidance paradigm. Animals were shocked with 0.5mA current and subsequently were microinjected bilaterally with 50ng or 100ng RFRP-1 in volume of 0.4μl, or 20ng NPFF receptor antagonist RF9 (ANT) alone, or antagonist 15min before 50ng RFRP-1 treatments into the CeA. Fifty nanogram dose of RFRP-1 significantly increased the step-through latency time, the 100ng RFRP-1 and the ANT alone were ineffective. The effect of 50ng RFRP-1 was eliminated by the ANT pretreatment. Our results suggest that intraamygdaloid RFRP-1 enhances learning processes and memory in aversive situations and this effect can specifically be prevented by ANT pretreatment.
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Affiliation(s)
- Anita Kovács
- Institute of Physiology, Pécs University Medical School, Hungary
| | - Kristóf László
- Institute of Physiology, Pécs University Medical School, Hungary
| | - Olga Zagoracz
- Institute of Physiology, Pécs University Medical School, Hungary
| | - Tamás Ollmann
- Institute of Physiology, Pécs University Medical School, Hungary
| | - László Péczely
- Institute of Physiology, Pécs University Medical School, Hungary
| | - Rita Gálosi
- Institute of Physiology, Pécs University Medical School, Hungary
| | - László Lénárd
- Institute of Physiology, Pécs University Medical School, Hungary; Molecular Neurophysiology Research Group, Pécs University, Szentágothai Research Center, Pécs, Hungary.
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Takayanagi Y, Yoshida M, Takashima A, Takanami K, Yoshida S, Nishimori K, Nishijima I, Sakamoto H, Yamagata T, Onaka T. Activation of Supraoptic Oxytocin Neurons by Secretin Facilitates Social Recognition. Biol Psychiatry 2017; 81:243-251. [PMID: 26803341 DOI: 10.1016/j.biopsych.2015.11.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 11/13/2015] [Accepted: 11/21/2015] [Indexed: 01/17/2023]
Abstract
BACKGROUND Social recognition underlies social behavior in animals, and patients with psychiatric disorders associated with social deficits show abnormalities in social recognition. Oxytocin is implicated in social behavior and has received attention as an effective treatment for sociobehavioral deficits. Secretin receptor-deficient mice show deficits in social behavior. The relationship between oxytocin and secretin concerning social behavior remains to be determined. METHODS Expression of c-Fos in oxytocin neurons and release of oxytocin from their dendrites after secretin application were investigated. Social recognition was examined after intracerebroventricular or local injection of secretin, oxytocin, or an oxytocin receptor antagonist in rats, oxytocin receptor-deficient mice, and secretin receptor-deficient mice. Electron and light microscopic immunohistochemical analysis was also performed to determine whether oxytocin neurons extend their dendrites into the medial amygdala. RESULTS Supraoptic oxytocin neurons expressed the secretin receptor. Secretin activated supraoptic oxytocin neurons and facilitated oxytocin release from dendrites. Secretin increased acquisition of social recognition in an oxytocin receptor-dependent manner. Local application of secretin into the supraoptic nucleus facilitated social recognition, and this facilitation was blocked by an oxytocin receptor antagonist injected into, but not outside of, the medial amygdala. In the medial amygdala, dendrite-like thick oxytocin processes were found to extend from the supraoptic nucleus. Furthermore, oxytocin treatment restored deficits of social recognition in secretin receptor-deficient mice. CONCLUSIONS The results of our study demonstrate that secretin-induced dendritic oxytocin release from supraoptic neurons enhances social recognition. The newly defined secretin-oxytocin system may lead to a possible treatment for social deficits.
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Affiliation(s)
- Yuki Takayanagi
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Tochigi
| | - Masahide Yoshida
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Tochigi
| | - Akihide Takashima
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Tochigi
| | - Keiko Takanami
- Ushimado Marine Institute, Graduate School of Natural Science and Technology, Okayama University, Okayama
| | - Shoma Yoshida
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Tochigi
| | - Katsuhiko Nishimori
- Laboratory of Molecular Biology, Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan
| | - Ichiko Nishijima
- Department of Biobank Lifescience, Tohoku Medical Megabank Organization, Tohoku University, Miyagi, Japan
| | - Hirotaka Sakamoto
- Ushimado Marine Institute, Graduate School of Natural Science and Technology, Okayama University, Okayama
| | | | - Tatsushi Onaka
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Tochigi.
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RFamide-related peptide-3 (RFRP-3) suppresses sexual maturation in a eusocial mammal. Proc Natl Acad Sci U S A 2017; 114:1207-1212. [PMID: 28096421 DOI: 10.1073/pnas.1616913114] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Neuroendocrine mechanisms underlying social inhibition of puberty are not well understood. Here, we use a model exhibiting the most profound case of pubertal suppression among mammals to explore a role for RFamide-related peptide-3 [RFRP-3; mammalian ortholog to gonadotropin-inhibitory hormone (GnIH)] in neuroendocrine control of reproductive development. Naked mole rats (NMRs) live in sizable colonies where breeding is monopolized by two to four dominant animals, and no other members exhibit signs of puberty throughout their lives unless they are removed from the colony. Because of its inhibitory action on the reproductive axis in other vertebrates, we investigated the role of RFRP-3 in social reproductive suppression in NMRs. We report that RFRP-3 immunofluorescence expression patterns and RFRP-3/GnRH cross-talk are largely conserved in the NMR brain, with the exception of the unique presence of RFRP-3 cell bodies in the arcuate nucleus (Arc). Immunofluorescence comparisons revealed that central expression of RFRP-3 is altered by reproductive status, with RFRP-3 immunoreactivity enhanced in the paraventricular nucleus, dorsomedial nucleus, and Arc of reproductively quiescent NMRs. We further observed that exogenous RFRP-3 suppresses gonadal steroidogenesis and mating behavior in NMRs given the opportunity to undergo puberty. Together, our findings establish a role for RFRP-3 in preserving reproductive immaturity, and challenge the view that stimulatory peptides are the ultimate gatekeepers of puberty.
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Teo CH, Soga T, Parhar IS. Social Isolation Modulates CLOCK Protein and Beta-Catenin Expression Pattern in Gonadotropin-Inhibitory Hormone Neurons in Male Rats. Front Endocrinol (Lausanne) 2017; 8:225. [PMID: 28936198 PMCID: PMC5594079 DOI: 10.3389/fendo.2017.00225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 08/21/2017] [Indexed: 12/14/2022] Open
Abstract
Postweaning social isolation reduces the amplitude of the daily variation of CLOCK protein in the brain and induces lower reproductive activity. Gonadotropin-inhibitory hormone (GnIH) acts as an inhibitor in the reproductive system and has been linked to stress. Social isolation has been shown to lower neuronal activity of GnIH-expressing neurons in the dorsomedial hypothalamus (DMH). The exact mechanism by which social isolation may affect GnIH is still unclear. We investigated the impact of social isolation on regulatory cellular mechanisms in GnIH neurons. We examined via immunohistochemistry the expression of CLOCK protein at four different times throughout the day in GnIH cells tagged with enhanced fluorescent green protein (EGFP-GnIH) in 9-week-old adult male rats that have been raised for 6 weeks under postweaning social isolation and compared them with group-raised control rats of the same age. We also studied the expression of β-catenin-which has been shown to be affected by circadian proteins such as Bmal1-in EGFP-GnIH neurons to determine whether it could play a role in linking CLOCK in GnIH neurons. We found that social isolation modifies the pattern of CLOCK expression in GnIH neurons in the DMH. Socially isolated rats displayed greater CLOCK expression in the dark phase, while control rats displayed increased CLOCK expression in the light phase. Furthermore, β-catenin expression pattern in GnIH cells was disrupted by social isolation. This suggests that social isolation triggers changes in CLOCK and GnIH expression, which may be associated with an increase in nuclear β-catenin during the dark phase.
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Affiliation(s)
- Chuin Hau Teo
- School of Medicine and Health Sciences, Brain Research Institute, Monash University Malaysia, Subang Jaya, Malaysia
| | - Tomoko Soga
- School of Medicine and Health Sciences, Brain Research Institute, Monash University Malaysia, Subang Jaya, Malaysia
- *Correspondence: Tomoko Soga,
| | - Ishwar S. Parhar
- School of Medicine and Health Sciences, Brain Research Institute, Monash University Malaysia, Subang Jaya, Malaysia
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32
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Seymour AJ, Scott V, Augustine RA, Bouwer GT, Campbell RE, Brown CH. Development of an excitatory kisspeptin projection to the oxytocin system in late pregnancy. J Physiol 2016; 595:825-838. [PMID: 27589336 DOI: 10.1113/jp273051] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 08/23/2016] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Oxytocin release from the posterior pituitary gland stimulates uterine contraction during birth but the central mechanisms that activate oxytocin neurones for birth are not well characterized. We found that that kisspeptin fibre density around oxytocin neurones increases in late-pregnant rats. These kisspeptin fibres originated from hypothalamic periventricular nucleus neurones that upregulated kisspeptin expression in late pregnancy. Oxytocin neurones were excited by central kisspeptin administration in late-pregnant rats but not in non-pregnant rats or early- to mid-pregnant rats. Our results reveal the emergence of a new excitatory kisspeptin projection to the oxytocin system in late pregnancy that might contribute to oxytocin neurone activation for birth. ABSTRACT The hormone oxytocin promotes uterine contraction during parturition. Oxytocin is synthesized by magnocellular neurones in the hypothalamic supraoptic and paraventricular nuclei and is released into the circulation from the posterior pituitary gland in response to action potential firing. Systemic kisspeptin administration increases oxytocin neurone activity to elevate plasma oxytocin levels. Here, immunohistochemistry revealed that rats on the expected day of parturition (day 21 of gestation) had a higher density of kisspeptin-positive fibres in the perinuclear zone surrounding the supraoptic nucleus (which provides dense glutamatergic and GABAergic innervation to the supraoptic nucleus) than was evident in non-pregnant rats. Retrograde tracing showed the kisspeptin projections to the perinuclear zone originated from the hypothalamic periventricular nucleus. Quantitative RT-PCR showed that kisspeptin receptor mRNA, Kiss1R mRNA, was expressed in the perinuclear zone-supraoptic nucleus and that the relative Kiss1R mRNA expression does not change over the course of pregnancy. Finally, intracerebroventricular administration of kisspeptin increased the firing rate of oxytocin neurones in anaesthetized late-pregnant rats (days 18-21 of gestation) but not in non-pregnant rats, or in early- or mid-pregnant rats. Taken together, these results suggest that kisspeptin expression is upregulated in the periventricular nucleus projection to the perinuclear zone of the supraoptic nucleus towards the end of pregnancy. Hence, this input might activate oxytocin neurones during parturition.
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Affiliation(s)
- Alexander J Seymour
- Brain Health Research Centre, University of Otago, Dunedin, New Zealand.,Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Victoria Scott
- Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Rachael A Augustine
- Brain Health Research Centre, University of Otago, Dunedin, New Zealand.,Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Gregory T Bouwer
- Brain Health Research Centre, University of Otago, Dunedin, New Zealand.,Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Rebecca E Campbell
- Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Colin H Brown
- Brain Health Research Centre, University of Otago, Dunedin, New Zealand.,Centre for Neuroendocrinology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.,Department of Physiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
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Ullah R, Shen Y, Zhou YD, Huang K, Fu JF, Wahab F, Shahab M. Expression and actions of GnIH and its orthologs in vertebrates: Current status and advanced knowledge. Neuropeptides 2016; 59:9-20. [PMID: 27255391 DOI: 10.1016/j.npep.2016.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/01/2016] [Accepted: 05/23/2016] [Indexed: 12/20/2022]
Abstract
The physiology of reproduction is very complex and is regulated by multiple factors, including a number of hypothalamic neuropeptides. In last few decades, various neuropeptides have been discovered to be involved in stimulation or inhibition of reproduction. In 2000, Tsutsui and colleagues uncovered gonadotropin-inhibitory hormone (GnIH), a neuropeptide generating inhibitory drive to the reproductive axis, in the brain of Coturnix quail. Afterward, GnIH orthologs were discovered in other vertebrates from fish to mammals including human. In these vertebrates, all the discovered GnIH and its ortholgs have LPXRFamide (X=L or Q) sequence at C-terminus. GnIH orthologs of mammals and primates are also termed as RFamide-related peptide (RFRP)-1 and -3 that too have an LPXRFamide (X=L or Q) motif at their C-terminus. GnIH and its orthologs form a member of the RFamide peptide family. GnIH signals via its canonical G protein coupled receptor 147 (GPR147). Both GnIH and GPR147 are expressed in hypothalamus and other brain regions. Besides actions through the hypothalamic GnRH and kisspeptinergic neurons, GnIH-GPR147 signaling exerts inhibitory effect on the reproductive axis via pituitary gonadotropes and directly at gonadal level. Various factors including availability and quality of food, photoperiod, temperature, social interaction, various stresses and some diseases modulate GnIH-GPR147 signaling. In this review, we have discussed expression and actions of GnIH and its orthologs in vertebrates. Special emphasis is given on the role of GnIH-GPR147 signaling pathway in the regulation of reproduction. We have also reviewed and discussed currently available literature on the participation of GnIH-GPR147 signaling pathway in the stress modulation of reproduction.
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Affiliation(s)
- Rahim Ullah
- Department of Endocrinology, Children Hospital of Zhejiang University, School of Medicine, Zhejiang University, Hangzhou, China; Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; Key Laboratory of Medical Neurobiology of Ministry of Health and Zhejiang Province, Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Yi Shen
- Key Laboratory of Medical Neurobiology of Ministry of Health and Zhejiang Province, Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Yu-Dong Zhou
- Key Laboratory of Medical Neurobiology of Ministry of Health and Zhejiang Province, Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Ke Huang
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Jun-Fen Fu
- Department of Endocrinology, Children Hospital of Zhejiang University, School of Medicine, Zhejiang University, Hangzhou, China.
| | - Fazal Wahab
- Stem Cell Biology Unit, German Primate Center, Leibniz-Institute for Primate Research, Kellnerweg 4, 37077 Gottingen, Germany
| | - Muhammad Shahab
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
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Kim JS. What's in a Name? Roles of RFamide-Related Peptides Beyond Gonadotrophin Inhibition. J Neuroendocrinol 2016; 28. [PMID: 27369805 DOI: 10.1111/jne.12407] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 12/29/2022]
Abstract
RFamide-related peptides (RFRPs) have been heavily implicated in the control of reproductive function subsequent to their discovery more than 16 years ago. However, recent studies using genetic and pharmacological tools have challenged their importance in regulating the hypothalamic-pituitary-gonadal axis. It is generally accepted that RFRPs act as part of a wider RFamide system, which involves two receptors, called the neuropeptide FF receptors (NPFFR1 and R2), and includes the closely-related neuropeptide NPFF. NPFF has been studied ever since the 1980s and many of the functions of NPFF are also shared by RFRPs. The current review questions whether these functions of NPFF are indeed specific to just NPFF alone and presents evidence from both neuroendocrine and pharmacological perspectives. Furthermore, recently emerging new functions of RFRPs are discussed with the overall goal of clarifying the functions of RFRPs beyond the hypothalamic-pituitary-gonadal axis.
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Affiliation(s)
- J S Kim
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago, Dunedin, New Zealand
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Tanco VM, Whitlock BK, Jones MA, Wilborn RR, Brandebourg TD, Foradori CD. Distribution and regulation of gonadotropin-releasing hormone, kisspeptin, RF-amide related peptide-3, and dynorphin in the bovine hypothalamus. PeerJ 2016; 4:e1833. [PMID: 27014517 PMCID: PMC4806599 DOI: 10.7717/peerj.1833] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 03/01/2016] [Indexed: 01/06/2023] Open
Abstract
Recent work has led to the hypothesis that kisspeptin/neurokinin B/dynorphin (KNDy) neurons in the arcuate nucleus (ARC) play a key role in gonadotropin-releasing hormone (GnRH) pulse generation and gonadal steroid feedback, with kisspeptin driving GnRH release and neurokinin B and dynorphin acting as pulse start and stop signals, respectively. A separate cell group, expressing RFamide-related peptide-3 (RFRP-3) has been shown to be a primary inhibitor of GnRH release. Very little is known regarding these cell groups in the bovine. In this study, we examined the relative immunoreactivity of kisspeptin, dynorphin, and RFRP-3 and their possible connectivity to GnRH neurons in the hypothalami of periestrus and diestrus bovine. While GnRH and RFRP-3 immunoreactivity were unchanged, kisspeptin and dynorphin immunoreactivity levels varied in relation to plasma progesterone concentrations and estrous status. Animals with higher plasma progesterone concentrations in diestrus had lower kisspeptin and increased dynorphin immunoreactivity in the ARC. The percentage of GnRH cells with kisspeptin or RFRP-3 fibers in close apposition did not differ between estrous stages. However, the proportions of GnRH cells with kisspeptin or RFRP-3 contacts (∼49.8% and ∼31.3%, respectively) suggest direct communication between kisspeptin and RFRP-3 cells to GnRH cells in the bovine. The data produced in this work support roles for kisspeptin and dynorphin, within the KNDy neural network, in controlling GnRH release over the ovarian cycle and conveying progesterone-negative feedback onto GnRH neurons in the bovine.
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Affiliation(s)
- Valeria M Tanco
- Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee-Knoxville , Knoxville, TN , United States
| | - Brian K Whitlock
- Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee-Knoxville , Knoxville, TN , United States
| | - Melaney A Jones
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University , Auburn, AL , United States
| | - Robyn R Wilborn
- Department of Clinical Sciences, College of Veterinary Medicine, Auburn University , Auburn, AL , United States
| | - Terry D Brandebourg
- Department of Animal Sciences, College of Agriculture, Auburn University , Auburn, AL , United States
| | - Chad D Foradori
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University , Auburn, AL , United States
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Ogawa S, Sivalingam M, Biran J, Golan M, Anthonysamy RS, Levavi-Sivan B, Parhar IS. Distribution of LPXRFa, a gonadotropin-inhibitory hormone ortholog peptide, and LPXRFa receptor in the brain and pituitary of the tilapia. J Comp Neurol 2016; 524:2753-75. [PMID: 26917324 DOI: 10.1002/cne.23990] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/18/2016] [Accepted: 02/19/2016] [Indexed: 11/09/2022]
Abstract
In vertebrates, gonadotropin-releasing hormone (GnRH) and gonadotropin-inhibitory hormone (GnIH), respectively, regulate reproduction in positive and negative manners. GnIH belongs to the LPXRFa family of peptides previously identified in mammalian and nonmammalian vertebrates. Studying the detailed distribution of LPXRFa as well as its receptor (LPXRFa-R) in the brain and pituitary is important for understanding their multiple action sites and potential functions. However, the distribution of LPXRFa and LPXRFa-R has not been studied in teleost species, partially because of the lack of fish-specific antibodies. Therefore, in the present study, we generated specific antibodies against LPXRFa and its receptor from Nile tilapia (Oreochromis niloticus), and examined their distributions in the brain and pituitary by immunohistochemistry. Tilapia LPXRFa-immunoreactive neurons lie in the posterior ventricular nucleus of the caudal preoptic area, whereas LPXRFa-R-immunoreactive cells are distributed widely. Double immunofluorescence showed that neither LPXRFa-immunoreactive fibers nor LPXRFa-R is closely associated or coexpressed with GnRH1, GnRH3, or kisspeptin (Kiss2) neurons. In the pituitary, LPXRFa fibers are closely associated with gonadotropic endocrine cells [expressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH)], with adrenocorticomelanotropic cells [corticotropin (ACTH) and α-melanotropin (α-MSH)], and with somatolactin endocrine cells. In contrast, LPXRFa-R are expressed only in LH, ACTH, and α-MSH cells. These results suggest that LPXRFa and LPXRFa-R signaling acts directly on the pituitary cells independent from GnRH or kisspeptin and could play multiple roles in reproductive and nonreproductive functions in teleosts. J. Comp. Neurol. 524:2753-2775, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Satoshi Ogawa
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Mageswary Sivalingam
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Jakob Biran
- Department of Animal Sciences, The Robert H Smith Faculty of Agriculture, Food, and Environment, Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Matan Golan
- Department of Animal Sciences, The Robert H Smith Faculty of Agriculture, Food, and Environment, Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Rachel Shalini Anthonysamy
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Berta Levavi-Sivan
- Department of Animal Sciences, The Robert H Smith Faculty of Agriculture, Food, and Environment, Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Ishwar S Parhar
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
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Quillet R, Ayachi S, Bihel F, Elhabazi K, Ilien B, Simonin F. RF-amide neuropeptides and their receptors in Mammals: Pharmacological properties, drug development and main physiological functions. Pharmacol Ther 2016; 160:84-132. [PMID: 26896564 DOI: 10.1016/j.pharmthera.2016.02.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RF-amide neuropeptides, with their typical Arg-Phe-NH2 signature at their carboxyl C-termini, belong to a lineage of peptides that spans almost the entire life tree. Throughout evolution, RF-amide peptides and their receptors preserved fundamental roles in reproduction and feeding, both in Vertebrates and Invertebrates. The scope of this review is to summarize the current knowledge on the RF-amide systems in Mammals from historical aspects to therapeutic opportunities. Taking advantage of the most recent findings in the field, special focus will be given on molecular and pharmacological properties of RF-amide peptides and their receptors as well as on their implication in the control of different physiological functions including feeding, reproduction and pain. Recent progress on the development of drugs that target RF-amide receptors will also be addressed.
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Affiliation(s)
- Raphaëlle Quillet
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Safia Ayachi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Bihel
- Laboratoire Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, Illkirch, France
| | - Khadija Elhabazi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Brigitte Ilien
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Simonin
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France.
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Ubuka T, Son YL, Tsutsui K. Molecular, cellular, morphological, physiological and behavioral aspects of gonadotropin-inhibitory hormone. Gen Comp Endocrinol 2016; 227:27-50. [PMID: 26409890 DOI: 10.1016/j.ygcen.2015.09.009] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/09/2015] [Accepted: 09/11/2015] [Indexed: 12/15/2022]
Abstract
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that was isolated from the brains of Japanese quail in 2000, which inhibited luteinizing hormone release from the anterior pituitary gland. Here, we summarize the following fifteen years of researches that investigated on the mechanism of GnIH actions at molecular, cellular, morphological, physiological, and behavioral levels. The unique molecular structure of GnIH peptide is in its LPXRFamide (X=L or Q) motif at its C-terminal. The primary receptor for GnIH is GPR147. The cell signaling pathway triggered by GnIH is initiated by inhibiting adenylate cyclase and decreasing cAMP production in the target cell. GnIH neurons regulate not only gonadotropin synthesis and release in the pituitary, but also regulate various neurons in the brain, such as GnRH1, GnRH2, dopamine, POMC, NPY, orexin, MCH, CRH, oxytocin, and kisspeptin neurons. GnIH and GPR147 are also expressed in gonads and they may regulate steroidogenesis and germ cell maturation in an autocrine/paracrine manner. GnIH regulates reproductive development and activity. In female mammals, GnIH may regulate estrous or menstrual cycle. GnIH is also involved in the regulation of seasonal reproduction, but GnIH may finely tune reproductive activities in the breeding seasons. It is involved in stress responses not only in the brain but also in gonads. GnIH may inhibit male socio-sexual behavior by stimulating the activity of cytochrome P450 aromatase in the brain and stimulates feeding behavior by modulating the activities of hypothalamic and central amygdala neurons.
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Affiliation(s)
- Takayoshi Ubuka
- Department of Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo 162-8480, Japan; Brain Research Institute Monash Sunway (BRIMS) of the Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya 46150, Malaysia.
| | - You Lee Son
- Department of Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo 162-8480, Japan
| | - Kazuyoshi Tsutsui
- Department of Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo 162-8480, Japan.
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Salehi MS, Tamadon A, Jafarzadeh Shirazi MR, Namavar MR, Zamiri MJ. The Role of Arginine-Phenylalanine-Amide-Related Peptides in Mammalian Reproduction. INTERNATIONAL JOURNAL OF FERTILITY & STERILITY 2015; 9:268-76. [PMID: 26644848 PMCID: PMC4671388 DOI: 10.22074/ijfs.2015.4540] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 05/20/2014] [Indexed: 01/23/2023]
Abstract
Until 2000 it was believed that gonadotropin-releasing hormone (GnRH) was the
sole regulator of hypophyseal gonadotropes. In 2000, the discovery of a gonadotropin inhibitory hormone (GnIH) initiated a revolution in the field of reproductive
physiology. Identification of GnIH homologues in mammals, the arginine-phenylalanine-amide (RFamide)-related peptides (RFRPs), indicated a similar function.
Subsequently, further works conducted in various laboratories worldwide have
shown that these neuropeptides inhibit the hypothalamic-hypophyseal axis. This review discusses the role of RFRPs in mammalian reproductive processes.
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Affiliation(s)
- Mohammad Saied Salehi
- Department of Animal Science, College of Agriculture, Shiraz University, Shiraz, Iran
| | - Amin Tamadon
- Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Mohammad Reza Namavar
- Histomorphometry and Stereology Research Center, Clinical Neurology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Javad Zamiri
- Department of Animal Science, College of Agriculture, Shiraz University, Shiraz, Iran
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Kim JS, Brownjohn PW, Dyer BS, Beltramo M, Walker CS, Hay DL, Painter GF, Tyndall JDA, Anderson GM. Anxiogenic and Stressor Effects of the Hypothalamic Neuropeptide RFRP-3 Are Overcome by the NPFFR Antagonist GJ14. Endocrinology 2015; 156:4152-62. [PMID: 26259035 DOI: 10.1210/en.2015-1532] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RFamide-related peptide-3 (RFRP-3) is a recently discovered neuropeptide that has been proposed to play a role in the stress response. We aimed to elucidate the role of RFRP-3 and its receptor, neuropeptide FF (NPFF1R), in modulation of stress and anxiety responses. To achieve this, we characterized a new NPFF1R antagonist because our results showed that the only commercially available putative antagonist, RF9, is in fact an agonist at both NPFF1R and the kisspeptin receptor (KISS1R). We report here the identification and pharmacological characterization of GJ14, a true NPFFR antagonist. In in vivo tests of hypothalamic-pituitary-adrenal (HPA) axis function, GJ14 completely blocked RFRP-3-induced corticosterone release and neuronal activation in CRH neurons. Furthermore, chronic infusion of GJ14 led to anxiolytic-like behavior, whereas RFRP-3 infusion had anxiogenic effects. Mice receiving chronic RFRP-3 infusion also had higher basal circulating corticosterone levels. These results indicate a stimulatory action of RFRP-3 on the HPA axis, consistent with the dense expression of NPFF1R in the vicinity of CRH neurons. Importantly, coinfusion of RFRP-3 and GJ14 completely reversed the anxiogenic and HPA axis-stimulatory effects of RFRP-3. Here we have established the role of RFRP-3 as a regulator of stress and anxiety. We also show that GJ14 can reverse the effects of RFRP-3 both in vitro and in vivo. Infusion of GJ14 causes anxiolysis, revealing a novel potential target for treating anxiety disorders.
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Affiliation(s)
- Joon S Kim
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Phil W Brownjohn
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Blake S Dyer
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Massimiliano Beltramo
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Christopher S Walker
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Debbie L Hay
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Gavin F Painter
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Joel D A Tyndall
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
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Rietema SE, Blackberry MA, Maloney SK, Martin GB, Hawken PAR, Blache D. Twenty-four-hour profiles of metabolic and stress hormones in sheep selected for a calm or nervous temperament. Domest Anim Endocrinol 2015; 53:78-87. [PMID: 26143303 DOI: 10.1016/j.domaniend.2015.05.005] [Citation(s) in RCA: 8] [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: 02/01/2015] [Revised: 05/25/2015] [Accepted: 05/31/2015] [Indexed: 11/19/2022]
Abstract
Even in the absence of stressors, temperament is associated with changes in the concentration of stress-responsive hormones and, possibly because of such changes, temperament can affect metabolism. We tested whether, in sheep bred for temperament for 14 generations, "nervous" females have greater concentrations of stress-responsive hormones in the absence of stressors than "calm" females, and whether these differences are associated with changes in the concentrations of metabolic hormones. In resting "calm" (n = 8) and "nervous" (n = 8) sheep, concentrations of cortisol, prolactin, leptin, and insulin were measured in blood plasma sampled via jugular catheter every 20 min for 24 h. The animals were individually penned, habituated to their housing and human handling over 7 wk, and fed before sampling began. Diurnal variation was evident for all hormones, but a 24-h cortisol pattern was detected in only 7 individuals. There was no effect of temperament on any aspect of concentrations of cortisol or prolactin, but "calm" animals had greater concentrations of insulin in the early afternoon than "nervous" animals (14.5 ± 1.1 vs 10.0 ± 1.6 μU/mL; P = 0.038), and a similar tendency was seen for leptin (P = 0.092). We conclude that selection for temperament affects the concentration of metabolic hormones in the absence of stressors, but this effect is independent of stress-responsive hormones.
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Affiliation(s)
- S E Rietema
- The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, 6009, Australia; The School of Animal Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - M A Blackberry
- The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, 6009, Australia; The School of Animal Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - S K Maloney
- The School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - G B Martin
- The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, 6009, Australia; The School of Animal Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - P A R Hawken
- The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, 6009, Australia; The School of Animal Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - D Blache
- The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, 6009, Australia; The School of Animal Biology, The University of Western Australia, Crawley, Western Australia, 6009, Australia.
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Wahab F, Shahab M, Behr R. The involvement of gonadotropin inhibitory hormone and kisspeptin in the metabolic regulation of reproduction. J Endocrinol 2015; 225:R49-66. [PMID: 25957191 DOI: 10.1530/joe-14-0688] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recently, kisspeptin (KP) and gonadotropin inhibitory hormone (GnIH), two counteracting neuropeptides, have been acknowledged as significant regulators of reproductive function. KP stimulates reproduction while GnIH inhibits it. These two neuropeptides seem to be pivotal for the modulation of reproductive activity in response to internal and external cues. It is well-documented that the current metabolic status of the body is closely linked to its reproductive output. However, how reproductive function is regulated by the body's energy status is less clear. Recent studies have suggested an active participation of hypothalamic KP and GnIH in the modulation of reproductive function according to available metabolic cues. Expression of KISS1, the KP encoding gene, is decreased while expression of RFRP (NPVF), the gene encoding GnIH, is increased in metabolic deficiency conditions. The lower levels of KP, as suggested by a decrease in KISS1 gene mRNA expression, during metabolic deficiency can be corrected by administration of exogenous KP, which leads to an increase in reproductive hormone levels. Likewise, administration of RF9, a GnIH receptor antagonist, can reverse the inhibitory effect of fasting on testosterone in monkeys. Together, it is likely that the integrated function of both these hypothalamic neuropeptides works as a reproductive output regulator in response to a change in metabolic status. In this review, we have summarized literature from nonprimate and primate studies that demonstrate the involvement of KP and GnIH in the metabolic regulation of reproduction.
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Affiliation(s)
- F Wahab
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
| | - M Shahab
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
| | - R Behr
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
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Vega MG, Zarek SM, Bhagwat M, Segars JH. Gonadotropin surge-inhibiting/attenuating factors: a review of current evidence, potential applications, and future directions for research. Mol Reprod Dev 2015; 82:2-16. [PMID: 25581424 DOI: 10.1002/mrd.22439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 10/29/2014] [Indexed: 11/12/2022]
Abstract
Animal studies in the 1980s suggested the existence of an ovarian hormone, termed gonadotropin surge-inhibiting/attenuating factor (GnSIF/AF), that modulates pituitary secretion of luteinizing hormone (LH). Given the importance of identifying regulatory factors of the hypothalamic-pituitary-ovarian axis and the accumulating data suggesting its existence, we conducted a comprehensive literature search using PubMed, Web of Science, Scopus, and Embase to identify articles related to GnSIF/AF. The search generated 161 publications, of which 97 were included in this study. Several attempts have been made to identify and characterize this hormone and several candidates have been identified, but the protein sequences of these putative GnSIF/AF factors differ widely from one study to another. In addition, while the RF-amide RFRP-3 is known foremost as a neuropeptide, some research supports an ovarian origin for this non-steroidal hormone, thereby suggesting a role for RFRP-3 either as a co-modulator of GnSIF/AF or as a gonadotropin-inhibiting factor in the hypothalamus (GnIH). Discovery of the KNDy neurons that modulate GnRH secretion, on the other hand, further encourages the search for substance(s) that modulate their activity and that indirectly affect LH secretion and the hypothalamic-pituitary-ovarian axis. While it has remained an elusive hormone, GnSIF/AF holds many potential applications for contraception, in vitro fertilization, and/or cancer as well as for understanding polycystic ovary syndrome, metabolic diseases, and/or pubertal development. In this review, we rigorously examine the available evidence regarding the existence of GnSIF/AF, previous attempts at its identification, limitations to its discovery, future directions of research, and potential clinical applications.
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Affiliation(s)
- Mario G Vega
- Department of Obstetrics and Gynecology, St. Luke's-Roosevelt Hospital, New York City, New York
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Leon S, Tena-Sempere M. Dissecting the Roles of Gonadotropin-Inhibitory Hormone in Mammals: Studies Using Pharmacological Tools and Genetically Modified Mouse Models. Front Endocrinol (Lausanne) 2015; 6:189. [PMID: 26779117 PMCID: PMC4700143 DOI: 10.3389/fendo.2015.00189] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/10/2015] [Indexed: 12/24/2022] Open
Abstract
Reproduction is essential for perpetuation of the species and, hence, is controlled by a sophisticated network of regulatory factors of central and peripheral origin that integrate at the hypothalamic-pituitary-gonadal (HPG) axis. Among the central regulators of reproduction, kisspeptins, as major stimulatory drivers of gonadotropin-releasing hormone (GnRH) neurosecretion, have drawn considerable interest in the last decade. However, the dynamic, if not cyclic (in the female), nature of reproductive function and the potency of kisspeptins and other stimulatory signals of the HPG axis make tenable the existence of counterbalance inhibitory mechanisms, which may keep stimulation at check and would allow adaptation of reproductive maturation and function to different endogenous and environmental conditions. In this context, discovery of the gonadotropin-inhibitory hormone (GnIH) in birds, and its mammalian homolog, RFRP, opened up the exciting possibility that this inhibitory signal might operate centrally to suppress, directly or indirectly, GnRH/gonadotropin secretion, thus reciprocally cooperating with other stimulatory inputs in the dynamic regulation of the reproductive hypothalamic-pituitary unit. After more than 15 years of active research, the role of GnIH/RFRP in the control of the HPG axis has been documented in different species. Yet, important aspects of the physiology of this system, especially regarding its relative importance and actual roles in the control of key facets of reproductive function, remain controversial. In the present work, we aim to provide a critical review of recent developments in this area, with special attention to studies in rodent models, using pharmacological tools and functional genomics. In doing so, we intend to endow the reader with an updated view of what is known (and what is not known) about the physiological role of GnIH/RFRP signaling in the control of mammalian reproduction.
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Affiliation(s)
- Silvia Leon
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
- Instituto de Salud Carlos III, CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia (IMIBIC/HURS), Córdoba, Spain
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
- Instituto de Salud Carlos III, CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia (IMIBIC/HURS), Córdoba, Spain
- FiDiPro Program, Department of Physiology, University of Turku, Turku, Finland
- *Correspondence: Manuel Tena-Sempere,
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Lénárd L, Kovács A, Ollmann T, Péczely L, Zagoracz O, Gálosi R, László K. Positive reinforcing effects of RFamide-related peptide-1 in the rat central nucleus of amygdala. Behav Brain Res 2014; 275:101-6. [DOI: 10.1016/j.bbr.2014.08.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 08/24/2014] [Accepted: 08/26/2014] [Indexed: 12/28/2022]
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Intraamygdaloid microinjection of RFamide-related peptide-3 decreases food intake in rats. Brain Res Bull 2014; 107:61-8. [DOI: 10.1016/j.brainresbull.2014.07.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/13/2014] [Accepted: 07/05/2014] [Indexed: 11/23/2022]
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Son YL, Ubuka T, Narihiro M, Fukuda Y, Hasunuma I, Yamamoto K, Belsham DD, Tsutsui K. Molecular basis for the activation of gonadotropin-inhibitory hormone gene transcription by corticosterone. Endocrinology 2014; 155:1817-26. [PMID: 24552400 DOI: 10.1210/en.2013-2076] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The inhibitory effect of stress on reproductive function is potentially mediated by high concentrations of circulating glucocorticoids (GCs) acting via the GC receptor (GR). Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that inhibits gonadotropin secretion. GnIH may mediate stress-induced reproductive dysfunction. However, it is not yet known whether GC-bound GR is directly involved in GnIH transcription. Here, we demonstrated the localization of GR mRNA in GnIH neurons in the paraventricular nucleus of quail, suggesting that GC can directly regulate GnIH transcription. We next showed that 24 hours of treatment with corticosterone (CORT) increase GnIH mRNA expression in the quail diencephalon. We further investigated the mechanism of activation of GnIH transcription by CORT using a GnIH-expressing neuronal cell line, rHypoE-23, derived from rat hypothalamus. We found the expression of GR mRNA in rHypoE-23 cells and increased GnIH mRNA expression by 24 hours of CORT treatment. We finally characterized the promoter activity of rat GnIH gene stimulated by CORT. Through DNA deletion analysis, we identified a CORT-responsive region at 2000-1501 bp upstream of GnIH precursor coding region. This region included 2 GC response elements (GREs) at -1665 and -1530 bp. Mutation of -1530 GRE abolished CORT responsiveness. We also found CORT-stimulated GR recruitment at the GnIH promoter region containing the -1530 GRE. These results provide a putative molecular basis for transcriptional activation of GnIH under stress by demonstrating that CORT directly induces GnIH transcription by recruitment of GR to its promoter.
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Affiliation(s)
- You Lee Son
- Laboratory of Integrative Brain Sciences (Y.L.S., T.U., M.N., Y.F., I.H., K.Y., K.T.), Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan; and Departments of Physiology (D.D.B.), Medicine, and Obstetrics and Gynaecology, University of Toronto, and Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada M5S 1A8
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Soga T, Kitahashi T, Clarke IJ, Parhar IS. Gonadotropin-inhibitory hormone promoter-driven enhanced green fluorescent protein expression decreases during aging in female rats. Endocrinology 2014; 155:1944-55. [PMID: 24605826 DOI: 10.1210/en.2013-1786] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Gonadotropin-inhibitory hormone (GnIH) neurons project to GnRH neurons to negatively regulate reproductive function. To fully explore the projections of the GnIH neurons, we created transgenic rats carrying an enhanced green fluorescent protein (EGFP) tagged to the GnIH promoter. With these animals, we show that EGFP-GnIH neurons are localized mainly in the dorsomedial hypothalamic nucleus (DMN) and project to the hypothalamus, telencephalon, and diencephalic thalamus, which parallels and confirms immunocytochemical and gene expression studies. We observed an age-related reduction in c-Fos-positive GnIH cell numbers in female rats. Furthermore, GnIH fiber appositions to GnRH neurons in the preoptic area were lessened in middle-aged females (70 weeks old) compared with their younger counterparts (9-12 weeks old). The fiber density in other brain areas was also reduced in middle-aged female rats. The expression of estrogen and progesterone receptors mRNA in subsets of EGFP-GnIH neurons was shown in laser-dissected single EGFP-GnIH neurons. We then examined estradiol-17β and progesterone regulation of GnIH neurons, using c-Fos presence as a marker. Estradiol-17β treatment reduced c-Fos labeling in EGFP-GnIH neurons in the DMN of young ovariectomized adult females but had no effect in middle-aged females. Progesterone had no effect on the number of GnIH cells positive for c-Fos. We conclude that there is an age-related decline in GnIH neuron number and GnIH inputs to GnRH neurons. We also conclude that the response of GnIH neurons to estrogen diminishes with reproductive aging.
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Affiliation(s)
- Tomoko Soga
- Brain Research Institute (T.S., T.K., I.S.P.), School of Medicine and Health Sciences, Monash University, Sunway, PJ 46150, Malaysia; and Department of Physiology (I.J.C.), Monash University, Victoria 3880, Australia
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Gojska NM, Belsham DD. Glucocorticoid receptor-mediated regulation of Rfrp (GnIH) and Gpr147 (GnIH-R) synthesis in immortalized hypothalamic neurons. Mol Cell Endocrinol 2014; 384:23-31. [PMID: 24412804 DOI: 10.1016/j.mce.2013.12.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 10/22/2013] [Accepted: 12/20/2013] [Indexed: 11/21/2022]
Abstract
A novel RFamide peptide, gonadotropin-inhibitory hormone (GnIH) has emerged as a modulator of avian reproduction. However, the functional role of the mammalian homologue, RFRP-3 remains poorly understood. The RFRP-3 neuronal circuit is influenced by the stress axis. However, whether the Rfrp gene is under direct glucocorticoid (GC)-mediated transcriptional regulation, in the presence and absence of the gonadal steroid, 17β-estradiol, is unknown. We investigated the regulation of the Rfrp (GnIH) and Gpr147 (GnIH-R) transcripts by steroids in a novel hypothalamic Rfrp-expressing cell model, rHypoE-23. The GC agonist, dexamethasone increased Rfrp and Gpr147 mRNA levels. Dexamethasone acted directly on the nuclear GC receptor (GR) to mediate GC-dependent transcriptional changes, independently of de novo protein synthesis. 17β-estradiol had no significant effect on Rfrp or Gpr147 biosynthesis in these neurons. This suggests that Rfrp-expressing neurons serve as potential upstream mediators of stress-induced effects through GR-dependent mechanisms.
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Affiliation(s)
- Nicole M Gojska
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Departments of Medicine and Obstetrics and Gynaecology, University of Toronto, Toronto, ON M5S 1A8, Canada; Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5S 1A8, Canada.
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Breen KM, Mellon PL. Influence of stress-induced intermediates on gonadotropin gene expression in gonadotrope cells. Mol Cell Endocrinol 2014; 385:71-7. [PMID: 24012628 PMCID: PMC3942370 DOI: 10.1016/j.mce.2013.08.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 08/14/2013] [Accepted: 08/21/2013] [Indexed: 11/20/2022]
Abstract
Despite extensive investigation, a comprehensive understanding of the mechanisms whereby stress impacts fertility remains elusive. Since the 1930s, when Hans Selye popularized studying adaptations to stress (Selye, 1937), we have learned that compensatory mechanisms involve a complex interplay of neural and hormonal processes that allow various body functions to adjust to stress, in a coordinated manner. In terms of reproduction, the adjustment to a stressor interferes with integrated functioning at multiple levels of regulation--the hypothalamus, anterior pituitary gland, gonads, and neural centers coordinating behavior. Various mediators are postulated to participate in reproductive suppression. These include catecholamines, cytokines, prostaglandins, endogenous opioid peptides, and hormones of the hypothalamic-pituitary-adrenal axis. This review focuses on one class of mediators, the glucocorticoids, and provides our views on the relevance and mode of action of this inhibitory intermediate within the anterior pituitary gonadotrope, as a potential cellular site whereby glucocorticoids contribute to stress-induced reproductive suppression.
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Affiliation(s)
- Kellie M Breen
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0674, United States.
| | - Pamela L Mellon
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0674, United States
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