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Prévot V, Tena-Sempere M, Pitteloud N. New Horizons: Gonadotropin-Releasing Hormone and Cognition. J Clin Endocrinol Metab 2023; 108:2747-2758. [PMID: 37261390 DOI: 10.1210/clinem/dgad319] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/25/2023] [Accepted: 05/30/2023] [Indexed: 06/02/2023]
Abstract
Pulsatile secretion of gonadotropin-releasing hormone (GnRH) is essential for activating and maintaining the function of the hypothalamic-pituitary-gonadal axis, which controls the onset of puberty and fertility. Two recent studies suggest that, in addition to controlling reproduction, the neurons in the brain that produce GnRH are also involved in the control of postnatal brain maturation, odor discrimination, and adult cognition. This review will summarize the development and establishment of the GnRH system, with particular attention to the importance of its first postnatal activation, a phenomenon known as minipuberty, for later reproductive and nonreproductive functions. In addition, we will discuss the beneficial effects of restoring physiological (ie, pulsatile) GnRH levels on olfactory and cognitive alterations in preclinical Down syndrome and Alzheimer disease models, as well as the potential risks associated with long-term continuous (ie, nonphysiological) GnRH administration in certain disorders. Finally, this review addresses the intriguing possibility that pulsatile GnRH therapy may hold therapeutic potential for the management of some neurodevelopmental cognitive disorders and pathological aging in elderly people.
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Affiliation(s)
- Vincent Prévot
- University of Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR S1172, Lille F-59000, France
| | - Manuel Tena-Sempere
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Nelly Pitteloud
- Department of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, Lausanne 1011, Switzerland
- Faculty of Biology and Medicine, Université of Lausanne, Lausanne 1005, Switzerland
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2
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Prévot V, Duittoz A. A role for GnRH in olfaction and cognition: Implications for veterinary medicine. Reprod Domest Anim 2023; 58 Suppl 2:109-124. [PMID: 37329313 DOI: 10.1111/rda.14411] [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: 04/24/2023] [Revised: 06/05/2023] [Accepted: 06/14/2023] [Indexed: 06/19/2023]
Abstract
Pulsatile secretion of gonadotropin-releasing hormone (GnRH) is essential for the activation and maintenance of the function of the hypothalamic-pituitary-gonadal (HPG) axis, which controls the onset of puberty and fertility. Two provocative recent studies suggest that, in addition to control reproduction, the neurons in the brain that produce GnRH are also involved in the control postnatal brain maturation, odour discrimination and adult cognition. Long-acting GnRH antagonists and agonists are commonly used to control fertility and behaviour in veterinary medicine, primarily in males. This review puts into perspective the potential risks of these androgen deprivation therapies and immunization on olfactory and cognitive performances and well-aging in domestic animals, including pets. We will also discuss the results reporting beneficial effects of pharmacological interventions restoring physiological GnRH levels on olfactory and cognitive alterations in preclinical models of Alzheimer's disease, which shares many pathophysiological and behavioural hallmarks with canine cognitive dysfunction. These novel findings raise the intriguing possibility that pulsatile GnRH therapy holds therapeutic potential for the management of this behavioural syndrome affecting older dogs.
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Affiliation(s)
- Vincent Prévot
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR_S1172, Lille, France
| | - Anne Duittoz
- Physiologie de la Reproduction et des Comportements (PRC) UMR7247 INRA, CNRS, Centre INRAE Val de Loire, IFCE, Université de Tours, Nouzilly, France
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3
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Guirado J, Carranza-Valencia J, Morante J. Mammalian puberty: a fly perspective. FEBS J 2023; 290:359-369. [PMID: 35607827 PMCID: PMC10084137 DOI: 10.1111/febs.16534] [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: 02/16/2022] [Revised: 05/02/2022] [Accepted: 05/23/2022] [Indexed: 02/05/2023]
Abstract
Mammalian puberty and Drosophila metamorphosis, despite their evolutionary distance, exhibit similar design principles and conservation of molecular components. In this Viewpoint, we review recent advances in this area and the similarities between both processes in terms of the signaling pathways and neuroendocrine circuits involved. We argue that the detection and uptake of peripheral fat by Drosophila prothoracic endocrine cells induces endomembrane remodeling and ribosomal maturation, leading to the acquisition of high biosynthetic and secretory capacity. The absence of this fat-neuroendocrine interorgan communication leads to giant, obese, non-pupating larvae. Importantly, human leptin is capable of signaling the pupariation process in Drosophila, and its expression prevents obesity and triggers maturation in mutants that do not pupate. This implies that insect metamorphosis can be used to address issues related to the biology of leptin and puberty.
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Affiliation(s)
- Juan Guirado
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
| | - Juan Carranza-Valencia
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
| | - Javier Morante
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
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4
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Prevot V, Sharif A. The polygamous GnRH neuron: Astrocytic and tanycytic communication with a neuroendocrine neuronal population. J Neuroendocrinol 2022; 34:e13104. [PMID: 35233849 DOI: 10.1111/jne.13104] [Citation(s) in RCA: 3] [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: 11/12/2021] [Revised: 01/12/2022] [Accepted: 01/30/2022] [Indexed: 11/28/2022]
Abstract
To ensure the survival of the species, hypothalamic neuroendocrine circuits controlling fertility, which converge onto neurons producing gonadotropin-releasing hormone (GnRH), must respond to fluctuating physiological conditions by undergoing rapid and reversible structural and functional changes. However, GnRH neurons do not act alone, but through reciprocal interactions with multiple hypothalamic cell populations, including several glial and endothelial cell types. For instance, it has long been known that in the hypothalamic median eminence, where GnRH axons terminate and release their neurohormone into the pituitary portal blood circulation, morphological plasticity displayed by distal processes of tanycytes modifies their relationship with adjacent neurons as well as the spatial properties of the neurohemal junction. These alterations not only regulate the capacity of GnRH neurons to release their neurohormone, but also the activation of discrete non-neuronal pathways that mediate feedback by peripheral hormones onto the hypothalamus. Additionally, a recent breakthrough has demonstrated that GnRH neurons themselves orchestrate the establishment of their neuroendocrine circuitry during postnatal development by recruiting an entourage of newborn astrocytes that escort them into adulthood and, via signalling through gliotransmitters such as prostaglandin E2, modulate their activity and GnRH release. Intriguingly, several environmental and behavioural toxins perturb these neuron-glia interactions and consequently, reproductive maturation and fertility. Deciphering the communication between GnRH neurons and other neural cell types constituting hypothalamic neuroendocrine circuits is thus critical both to understanding physiological processes such as puberty, oestrous cyclicity and aging, and to developing novel therapeutic strategies for dysfunctions of these processes, including the effects of endocrine disruptors.
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Affiliation(s)
- Vincent Prevot
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, FHU 1000 Days for Health, Lille, France
| | - Ariane Sharif
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, FHU 1000 Days for Health, Lille, France
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5
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Welch BA, Cho HJ, Ucakturk SA, Farmer SM, Cetinkaya S, Abaci A, Akkus G, Simsek E, Kotan LD, Turan I, Gurbuz F, Yuksel B, Wray S, Topaloglu AK. PLXNB1 mutations in the etiology of idiopathic hypogonadotropic hypogonadism. J Neuroendocrinol 2022; 34:e13103. [PMID: 35170806 DOI: 10.1111/jne.13103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/15/2022] [Accepted: 01/28/2022] [Indexed: 11/27/2022]
Abstract
Idiopathic hypogonadotropic hypogonadism (IHH) comprises a group of rare genetic disorders characterized by pubertal failure caused by gonadotropin-releasing hormone (GnRH) deficiency. Genetic factors involved in semaphorin/plexin signaling have been identified in patients with IHH. PlexinB1, a member of the plexin family receptors, serves as the receptor for semaphorin 4D (Sema4D). In mice, perturbations in Sema4D/PlexinB1 signaling leads to improper GnRH development, highlighting the importance of investigating PlexinB1 mutations in IHH families. In total, 336 IHH patients (normosmic IHH, n = 293 and Kallmann syndrome, n = 43) from 290 independent families were included in the present study. Six PLXNB1 rare sequence variants (p.N361S, p.V608A, p.R636C, p.V672A, p.R1031H, and p.C1318R) are described in eight normosmic IHH patients from seven independent families. These variants were examined using bioinformatic modeling and compared to mutants reported in PLXNA1. Based on these analyses, the variant p.R1031H was assayed for alterations in cell morphology, PlexinB1 expression, and migration using a GnRH cell line and Boyden chambers. Experiments showed reduced membrane expression and impaired migration in cells expressing this variant compared to the wild-type. Our results provide clinical, genetic, molecular/cellular, and modeling evidence to implicate variants in PLXNB1 in the etiology of IHH.
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Affiliation(s)
- Bradley A Welch
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, MS, USA
| | - Hyun-Ju Cho
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD, USA
| | - Seyit Ahmet Ucakturk
- Division of Pediatric Endocrinology, Ankara Training and Research Hospital, Ankara, Turkey
| | - Stephen Matthew Farmer
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD, USA
| | - Semra Cetinkaya
- Division of Pediatric Endocrinology, Dr. Sami Ulus Obstetrics and Gynecology, Pediatric Health and Disease Training and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Ayhan Abaci
- Division of Pediatric Endocrinology, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey
| | - Gamze Akkus
- Division of Endocrinology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Enver Simsek
- Division of Pediatric Endocrinology, Faculty of Medicine, Eskisehir Osman Gazi University, Eskisehir, Turkey
| | - Leman Damla Kotan
- Division of Pediatric Endocrinology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Ihsan Turan
- Division of Pediatric Endocrinology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Fatih Gurbuz
- Division of Pediatric Endocrinology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Bilgin Yuksel
- Division of Pediatric Endocrinology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Susan Wray
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD, USA
| | - A Kemal Topaloglu
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, MS, USA
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Mississippi Medical Center, Jackson, MS, USA
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6
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Vanacker C, Bouret SG, Giacobini P, Prévot V. [Precocious puberty and neuropilin-1 signaling in GnRH neurons]. Med Sci (Paris) 2021; 37:366-371. [PMID: 33908854 DOI: 10.1051/medsci/2021035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The survival of the species depends on two closely interlinked processes: the correct functioning of the reproductive system, and the balance between the energy needs of an individual and the supply of energy sources through feeding. These two processes are regulated in the hypothalamus, which produces neurohormones that control various physiological functions. Among these neurohormones, GnRH controls not only the maturation and function of the reproductive organs, including the ovaries and the testes, during puberty and in adulthood, but also sexual attraction. Recent evidence suggest that neuropilin-1-mediated signaling in GnRH-synthesizing neurons could be a linchpin that holds together various neuroanatomical, physiological and behavioral adaptations involved in triggering puberty and achieving reproductive function.
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Affiliation(s)
- Charlotte Vanacker
- Univ. Lille, Inserm, CHU Lille, Équipe développement et plasticité du cerveau neuroendocrine, FHU 1 000 jours pour la Santé, Lille Neuroscience et Cognition, UMR-S1172, 1 place de Verdun, 59045 Lille Cedex, France
| | - Sébastien G Bouret
- Univ. Lille, Inserm, CHU Lille, Équipe développement et plasticité du cerveau neuroendocrine, FHU 1 000 jours pour la Santé, Lille Neuroscience et Cognition, UMR-S1172, 1 place de Verdun, 59045 Lille Cedex, France
| | - Paolo Giacobini
- Univ. Lille, Inserm, CHU Lille, Équipe développement et plasticité du cerveau neuroendocrine, FHU 1 000 jours pour la Santé, Lille Neuroscience et Cognition, UMR-S1172, 1 place de Verdun, 59045 Lille Cedex, France
| | - Vincent Prévot
- Univ. Lille, Inserm, CHU Lille, Équipe développement et plasticité du cerveau neuroendocrine, FHU 1 000 jours pour la Santé, Lille Neuroscience et Cognition, UMR-S1172, 1 place de Verdun, 59045 Lille Cedex, France
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7
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Vanacker C, Trova S, Shruti S, Casoni F, Messina A, Croizier S, Malone S, Ternier G, Hanchate NK, Rasika S, Bouret SG, Ciofi P, Giacobini P, Prevot V. Neuropilin-1 expression in GnRH neurons regulates prepubertal weight gain and sexual attraction. EMBO J 2020; 39:e104633. [PMID: 32761635 PMCID: PMC7527814 DOI: 10.15252/embj.2020104633] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 07/01/2020] [Accepted: 07/13/2020] [Indexed: 12/26/2022] Open
Abstract
Hypothalamic neurons expressing gonadotropin-releasing hormone (GnRH), the "master molecule" regulating reproduction and fertility, migrate from their birthplace in the nose to their destination using a system of guidance cues, which include the semaphorins and their receptors, the neuropilins and plexins, among others. Here, we show that selectively deleting neuropilin-1 in new GnRH neurons enhances their survival and migration, resulting in excess neurons in the hypothalamus and in their unusual accumulation in the accessory olfactory bulb, as well as an acceleration of mature patterns of activity. In female mice, these alterations result in early prepubertal weight gain, premature attraction to male odors, and precocious puberty. Our findings suggest that rather than being influenced by peripheral energy state, GnRH neurons themselves, through neuropilin-semaphorin signaling, might engineer the timing of puberty by regulating peripheral adiposity and behavioral switches, thus acting as a bridge between the reproductive and metabolic axes.
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Affiliation(s)
- Charlotte Vanacker
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Sara Trova
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Sonal Shruti
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Filippo Casoni
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Andrea Messina
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Sophie Croizier
- Center for Integrative GenomicsUniversity of LausanneLausanneSwitzerland
| | - Samuel Malone
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Gaetan Ternier
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Naresh Kumar Hanchate
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - S Rasika
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Sebastien G Bouret
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Philippe Ciofi
- Inserm U1215Neurocentre MagendieBordeauxFrance
- Université de BordeauxBordeauxFrance
| | - Paolo Giacobini
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
| | - Vincent Prevot
- Laboratory of Development and Plasticity of the Neuroendocrine BrainUniv. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR‐S 1172LilleFrance
- FHU, 1000 Days for HealthLilleFrance
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8
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Tan CL, Sheard PW, Jasoni CL. Developing neurites from mouse basal forebrain gonadotropin-releasing hormone neurons use Sonic hedgehog to modulate their growth. Int J Dev Neurosci 2018; 68:89-97. [PMID: 29787797 DOI: 10.1016/j.ijdevneu.2018.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/14/2018] [Accepted: 05/14/2018] [Indexed: 02/07/2023] Open
Abstract
Hypothalamic gonadotropin-releasing hormone (GnRH) neurons are required for fertility in all mammalian species studied to date. GnRH neuron cell bodies reside in the basal forebrain, and most extend long neurites in the caudal direction to terminate at the median eminence (ME), the site of hormone secretion. Using in vitro neurite growth assays, histological methods, and genetic deletion strategies in mice we have analysed the role of the morphogen and neurite growth and guidance molecule, Sonic hedgehog (Shh), in the growth of GnRH neurites to their target. Immunohistochemistry revealed that Shh was present in the basal forebrain, the preoptic area (POA) and mediobasal hypothalamus (MBH) at gestational day 14.5 (GD 14.5), a time when GnRH neurites grow towards the ME. Furthermore, in situ hybridization revealed that mRNA encoding the Shh receptor, Smoothened (Smo), was present in GnRH neurons from GD 15.5, when the first GnRH neurites are extending towards the MBH. In vitro neurite growth assays using hypothalamic explants from GD 15.5 fetuses in 3-D collagen gels showed that Shh was able to significantly stimulate GnRH neurite outgrowth. Finally, genetic deletion of Smo specifically from GnRH neurons in vivo, using Cre-loxP technology, resulted in a significant decrease in GnRH neurites innervating the ME. These experiments demonstrate that GnRH neurites use Shh for their neurite development, provide further understanding of the mechanisms by which GnRH nerve terminals arrive at their site of hormone secretion, and identify an additional hypothalamic neuronal population for which Shh/Smo signaling is developmentally important.
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Affiliation(s)
- C L Tan
- Department of Anatomy, University of Otago, School of Biomedical Sciences, Dunedin, 9054, New Zealand; Centre for Neuroendocrinology, University of Otago, School of Biomedical Sciences, Dunedin, 9054, New Zealand.
| | - P W Sheard
- Department of Physiology, University of Otago, School of Biomedical Sciences, Dunedin, 9054, New Zealand.
| | - C L Jasoni
- Department of Anatomy, University of Otago, School of Biomedical Sciences, Dunedin, 9054, New Zealand; Centre for Neuroendocrinology, University of Otago, School of Biomedical Sciences, Dunedin, 9054, New Zealand.
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9
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Sominsky L, Jasoni CL, Twigg HR, Spencer SJ. Hormonal and nutritional regulation of postnatal hypothalamic development. J Endocrinol 2018; 237:R47-R64. [PMID: 29545398 DOI: 10.1530/joe-17-0722] [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: 02/28/2018] [Accepted: 03/15/2018] [Indexed: 12/24/2022]
Abstract
The hypothalamus is a key centre for regulation of vital physiological functions, such as appetite, stress responsiveness and reproduction. Development of the different hypothalamic nuclei and its major neuronal populations begins prenatally in both altricial and precocial species, with the fine tuning of neuronal connectivity and attainment of adult function established postnatally and maintained throughout adult life. The perinatal period is highly susceptible to environmental insults that, by disrupting critical developmental processes, can set the tone for the establishment of adult functionality. Here, we review the most recent knowledge regarding the major postnatal milestones in the development of metabolic, stress and reproductive hypothalamic circuitries, in the rodent, with a particular focus on perinatal programming of these circuitries by hormonal and nutritional influences. We also review the evidence for the continuous development of the hypothalamus in the adult brain, through changes in neurogenesis, synaptogenesis and epigenetic modifications. This degree of plasticity has encouraging implications for the ability of the hypothalamus to at least partially reverse the effects of perinatal mal-programming.
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Affiliation(s)
- Luba Sominsky
- School of Health and Biomedical SciencesRMIT University, Melbourne, Victoria, Australia
| | - Christine L Jasoni
- School of Biomedical SciencesCentre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Hannah R Twigg
- School of Biomedical SciencesCentre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Sarah J Spencer
- School of Health and Biomedical SciencesRMIT University, Melbourne, Victoria, Australia
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10
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Clasadonte J, Prevot V. The special relationship: glia-neuron interactions in the neuroendocrine hypothalamus. Nat Rev Endocrinol 2018; 14:25-44. [PMID: 29076504 DOI: 10.1038/nrendo.2017.124] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Natural fluctuations in physiological conditions require adaptive responses involving rapid and reversible structural and functional changes in the hypothalamic neuroendocrine circuits that control homeostasis. Here, we discuss the data that implicate hypothalamic glia in the control of hypothalamic neuroendocrine circuits, specifically neuron-glia interactions in the regulation of neurosecretion as well as neuronal excitability. Mechanistically, the morphological plasticity displayed by distal processes of astrocytes, pituicytes and tanycytes modifies the geometry and diffusion properties of the extracellular space. These changes alter the relationship between glial cells of the hypothalamus and adjacent neuronal elements, especially at specialized intersections such as synapses and neurohaemal junctions. The structural alterations in turn lead to functional plasticity that alters the release and spread of neurotransmitters, neuromodulators and gliotransmitters, as well as the activity of discrete glial signalling pathways that mediate feedback by peripheral signals to the hypothalamus. An understanding of the contributions of these and other non-neuronal cell types to hypothalamic neuroendocrine function is thus critical both to understand physiological processes such as puberty, the maintenance of bodily homeostasis and ageing and to develop novel therapeutic strategies for dysfunctions of these processes, such as infertility and metabolic disorders.
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Affiliation(s)
- Jerome Clasadonte
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, U1172, Bâtiment Biserte, 1 Place de Verdun, 59045, Lille, Cedex, France
- University of Lille, FHU 1000 days for Health, School of Medicine, Lille 59000, France
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, U1172, Bâtiment Biserte, 1 Place de Verdun, 59045, Lille, Cedex, France
- University of Lille, FHU 1000 days for Health, School of Medicine, Lille 59000, France
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11
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Taroc EZM, Prasad A, Lin JM, Forni PE. The terminal nerve plays a prominent role in GnRH-1 neuronal migration independent from proper olfactory and vomeronasal connections to the olfactory bulbs. Biol Open 2017; 6:1552-1568. [PMID: 28970231 PMCID: PMC5665474 DOI: 10.1242/bio.029074] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Gonadotropin-releasing hormone-1 (GnRH-1) neurons (GnRH-1 ns) migrate from the developing olfactory pit into the hypothalamus during embryonic development. Migration of the GnRH-1 neurons is required for mammalian reproduction as these cells control release of gonadotropins from the anterior pituitary gland. Disturbances in GnRH-1 ns migration, GnRH-1 synthesis, secretion or signaling lead to varying degrees of hypogonadotropic hypogonadism (HH), which impairs pubertal onset and fertility. HH associated with congenital olfactory defects is clinically defined as Kallmann Syndrome (KS). The association of olfactory defects with HH in KS suggested a potential direct relationship between defective olfactory axonal routing, lack of olfactory bulbs (OBs) and aberrant GnRH-1 ns migration. However, it has never been experimentally proven that the formation of axonal connections of the olfactory/vomeronasal neurons to their functional targets are necessary for the migration of GnRH-1 ns to the hypothalamus. Loss-of-function of the Arx-1 homeobox gene leads to the lack of proper formation of the OBs with abnormal axonal termination of olfactory sensory neurons (
Yoshihara et al., 2005). Our data prove that correct development of the OBs and axonal connection of the olfactory/vomeronasal sensory neurons to the forebrain are not required for GnRH-1 ns migration, and suggest that the terminal nerve, which forms the GnRH-1 migratory scaffold, follows different guidance cues and differs in gene expression from olfactory/vomeronasal sensory neurons. Summary: Our work reveals that correct olfactory bulb development is not required for GnRH-1 neuronal migration. This study challenges the idea that GnRH-1 neuronal migration to the hypothalamus relies on correct routing of the olfactory and vomeronasal neurons and supports the existence of the TN in mammals.
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Affiliation(s)
- Ed Zandro M Taroc
- Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
| | - Aparna Prasad
- Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
| | - Jennifer M Lin
- Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
| | - Paolo E Forni
- Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
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Opposite-sex attraction in male mice requires testosterone-dependent regulation of adult olfactory bulb neurogenesis. Sci Rep 2016; 6:36063. [PMID: 27782186 PMCID: PMC5080553 DOI: 10.1038/srep36063] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 10/11/2016] [Indexed: 11/23/2022] Open
Abstract
Opposite-sex attraction in most mammals depends on the fine-tuned integration of pheromonal stimuli with gonadal hormones in the brain circuits underlying sexual behaviour. Neural activity in these circuits is regulated by sensory processing in the accessory olfactory bulb (AOB), the first central station of the vomeronasal system. Recent evidence indicates adult neurogenesis in the AOB is involved in sex behaviour; however, the mechanisms underlying this function are unknown. By using Semaphorin 7A knockout (Sema7A ko) mice, which show a reduced number of gonadotropin-releasing-hormone neurons, small testicles and subfertility, and wild-type males castrated during adulthood, we demonstrate that the level of circulating testosterone regulates the sex-specific control of AOB neurogenesis and the vomeronasal system activation, which influences opposite-sex cue preference/attraction in mice. Overall, these data highlight adult neurogenesis as a hub for the integration of pheromonal and hormonal cues that control sex-specific responses in brain circuits.
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Millar RP. New Insights into GnRH Neuron Development, Programming and Regulation in Health and Disease. Preface. Neuroendocrinology 2015; 102:181-3. [PMID: 26394199 DOI: 10.1159/000441115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Robert P Millar
- Centre for Neuroendocrinology and Mammal Research Institute, University of Pretoria, Pretoria, South Africa
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