1
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Lim LWC, Egnot CT, Papaioannou P, Yip SH. The Hypothalamic Arcuate Nucleus Dopaminergic Neurons: More Than Just Prolactin Secretion. Endocrinology 2025; 166:bqaf025. [PMID: 39919032 PMCID: PMC11837187 DOI: 10.1210/endocr/bqaf025] [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: 12/20/2024] [Revised: 01/30/2025] [Accepted: 02/06/2025] [Indexed: 02/09/2025]
Abstract
The hypothalamic arcuate nucleus dopaminergic (A12) neurons are well known for their central role in regulating prolactin secretion through a sophisticated negative feedback loop. In this canonical pathway, prolactin stimulates A12 neurons to release dopamine, which suppresses further prolactin release from lactotrophs in the anterior pituitary. However, a collective of recent and past evidence strongly implies that the A12 neurons are far more dynamic and multifaceted than previously appreciated. This minireview discusses the developmental trajectory of A12 neurons, from prenatal origins to postnatal maturation, highlighting their diversity and heterogeneity. Beyond their well-characterized role in prolactin regulation, the A12 neurons contribute to a broader array of hypothalamic functions, including autoregulation, metabolism, and growth. By shedding light on these underexplored roles, this review outlines the expansive significance of A12 neurons as more than mere gatekeepers of prolactin secretion, positioning them as versatile players in endocrine and metabolic homeostasis.
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Affiliation(s)
- Luis Wei Cheng Lim
- Centre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin 9016, New Zealand
| | - Christopher Thomas Egnot
- Centre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin 9016, New Zealand
| | - Panagiotis Papaioannou
- Centre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin 9016, New Zealand
| | - Siew Hoong Yip
- Centre for Neuroendocrinology, Department of Anatomy, University of Otago, Dunedin 9016, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand
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2
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Gusmao DO, de Sousa LMM, de Sousa ME, Rusew SJR, List EO, Kopchick JJ, Gomes AF, Campideli-Santana AC, Szawka RE, Donato J. Characterization and Regulation of the Neonatal Growth Hormone Surge. Endocrinology 2024; 165:bqae140. [PMID: 39446366 PMCID: PMC11544317 DOI: 10.1210/endocr/bqae140] [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: 09/10/2024] [Indexed: 11/09/2024]
Abstract
High neonatal growth hormone (GH) secretion has been described in several species. However, the neuroendocrine mechanisms behind this surge remain unknown. Thus, the pattern of postnatal GH secretion was investigated in mice and rats. Blood GH levels were very high on postnatal day (P)1 and progressively decreased until near zero by P17 in C57BL/6 mice without sex differences. This pattern was similar to that observed in rats, except that female rats showed higher GH levels on P1 than males. In comparison, follicle-stimulating hormone exhibited higher secretion in females during the first 3 weeks of life. Hypothalamic Sst mRNA and somatostatin neuroendocrine terminals in the median eminence were higher in P20/P21 mice than in newborns. Knockout mice for GH-releasing hormone (GHRH) receptor showed no GH surge, whereas knockdown mice for the Sst gene displayed increased neonatal GH peak. Leptin deficiency caused only minor effects on early-life GH secretion. GH receptor ablation in neurons or the entire body did not affect neonatal GH secretion, but the subsequent reduction in blood GH levels was attenuated or prevented by these genetic manipulations, respectively. This phenotype was also observed in knockout mice for the insulin-like growth factor-1 (IGF-1) receptor in GHRH neurons. Moreover, glucose-induced hyperglycemia overstimulated GH secretion in neonatal mice. In conclusion, GH surge in the first days of life is not regulated by negative feedback loops. However, neonatal GH secretion requires GHRH receptor, and is modulated by somatostatin and blood glucose levels, suggesting that this surge is controlled by hypothalamic-pituitary communication.
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MESH Headings
- Animals
- Female
- Growth Hormone/metabolism
- Growth Hormone/blood
- Animals, Newborn
- Male
- Mice, Knockout
- Mice, Inbred C57BL
- Somatostatin/metabolism
- Somatostatin/genetics
- Mice
- Receptor, IGF Type 1/metabolism
- Receptor, IGF Type 1/genetics
- Rats
- Receptors, Neuropeptide/genetics
- Receptors, Neuropeptide/metabolism
- Leptin/blood
- Leptin/metabolism
- Hypothalamus/metabolism
- Receptors, Pituitary Hormone-Regulating Hormone/genetics
- Receptors, Pituitary Hormone-Regulating Hormone/metabolism
- Growth Hormone-Releasing Hormone/metabolism
- Growth Hormone-Releasing Hormone/genetics
- Receptors, Somatotropin/genetics
- Receptors, Somatotropin/metabolism
- Follicle Stimulating Hormone/blood
- Follicle Stimulating Hormone/metabolism
- Insulin-Like Growth Factor I/metabolism
- Insulin-Like Growth Factor I/genetics
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Affiliation(s)
- Daniela O Gusmao
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Ligia M M de Sousa
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Maria E de Sousa
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Stephanie J R Rusew
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Andre F Gomes
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Ana C Campideli-Santana
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Raphael E Szawka
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
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3
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Zhu T, Li W. The regulation of prolactin secretion and its targeting function of teleost. Gen Comp Endocrinol 2024; 354:114530. [PMID: 38657738 DOI: 10.1016/j.ygcen.2024.114530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 04/07/2024] [Accepted: 04/20/2024] [Indexed: 04/26/2024]
Abstract
Prolactin is involved in regulating various physiological activities of vertebrates and is one of the most momentous pituitary hormones. However, not enough attention is currently paid to prolactin, especially in teleost. This paper aims to gather, organize, and analyze recent studies on the regulation and functions of prolactin. By comparing with other animal groups, it highlights the significant role of prolactin in fish reproduction, immunity, growth, and osmotic pressure regulation, as well as the upstream and downstream factors that may be involved in the regulation of prolactin functions were introduced to provide a theoretical basis for the in-depth study and potential practical application of prolactin.
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Affiliation(s)
- Tiansheng Zhu
- State Key Laboratory of Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Provincial Engineering Technology Research Center for Healthy Breeding of Important Economic Fish, Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 China
| | - Wensheng Li
- State Key Laboratory of Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Provincial Engineering Technology Research Center for Healthy Breeding of Important Economic Fish, Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 China.
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4
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Donato J, Kopchick JJ. New findings on brain actions of growth hormone and potential clinical implications. Rev Endocr Metab Disord 2024; 25:541-553. [PMID: 38060062 PMCID: PMC11156798 DOI: 10.1007/s11154-023-09861-x] [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] [Accepted: 11/29/2023] [Indexed: 12/08/2023]
Abstract
Growth hormone (GH) is secreted by somatotropic cells of the anterior pituitary gland. The classical effects of GH comprise the stimulation of cell proliferation, tissue and body growth, lipolysis, and insulin resistance. The GH receptor (GHR) is expressed in numerous brain regions. Notably, a growing body of evidence indicates that GH-induced GHR signaling in specific neuronal populations regulates multiple physiological functions, including energy balance, glucose homeostasis, stress response, behavior, and several neurological/cognitive aspects. The importance of central GHR signaling is particularly evident when the organism is under metabolic stress, such as pregnancy, chronic food deprivation, hypoglycemia, and prolonged exercise. These particular situations are associated with elevated GH secretion. Thus, central GH action represents an internal signal that coordinates metabolic, neurological, neuroendocrine, and behavioral adaptations that are evolutionarily advantageous to increase the chances of survival. This review summarizes and discusses recent findings indicating that the brain is an important target of GH, and GHR signaling in different neuronal populations regulates essential physiological functions.
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Affiliation(s)
- Jose Donato
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Lineu Prestes, 1524, Sao Paulo, SP, 05508-000, Brazil.
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA
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5
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Menezes F, Wasinski F, de Souza GO, Nunes AP, Bernardes ES, dos Santos SN, da Silva FFA, Peroni CN, Oliveira JE, Kopchick JJ, Brown RSE, Fernandez G, De Francesco PN, Perelló M, Soares CRJ, Donato J. The Pattern of GH Action in the Mouse Brain. Endocrinology 2024; 165:bqae057. [PMID: 38728240 PMCID: PMC11137758 DOI: 10.1210/endocr/bqae057] [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: 02/07/2024] [Revised: 04/12/2024] [Accepted: 05/10/2024] [Indexed: 05/12/2024]
Abstract
GH acts in numerous organs expressing the GH receptor (GHR), including the brain. However, the mechanisms behind the brain's permeability to GH and how this hormone accesses different brain regions remain unclear. It is well-known that an acute GH administration induces phosphorylation of the signal transducer and activator of transcription 5 (pSTAT5) in the mouse brain. Thus, the pattern of pSTAT5 immunoreactive cells was analyzed at different time points after IP or intracerebroventricular GH injections. After a systemic GH injection, the first cells expressing pSTAT5 were those near circumventricular organs, such as arcuate nucleus neurons adjacent to the median eminence. Both systemic and central GH injections induced a medial-to-lateral pattern of pSTAT5 immunoreactivity over time because GH-responsive cells were initially observed in periventricular areas and were progressively detected in lateral brain structures. Very few choroid plexus cells exhibited GH-induced pSTAT5. Additionally, Ghr mRNA was poorly expressed in the mouse choroid plexus. In contrast, some tanycytes lining the floor of the third ventricle expressed Ghr mRNA and exhibited GH-induced pSTAT5. The transport of radiolabeled GH into the hypothalamus did not differ between wild-type and dwarf Ghr knockout mice, indicating that GH transport into the mouse brain is GHR independent. Also, single-photon emission computed tomography confirmed that radiolabeled GH rapidly reaches the ventral part of the tuberal hypothalamus. In conclusion, our study provides novel and valuable information about the pattern and mechanisms behind GH transport into the mouse brain.
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Affiliation(s)
- Filipe Menezes
- Biotechnology Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Frederick Wasinski
- Departamento de Fisiologia e Biofísica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Brazil
- Department of Neurology and Neurosurgery, Federal University of Sao Paulo, Sao Paulo 04039-032, Brazil
| | - Gabriel O de Souza
- Departamento de Fisiologia e Biofísica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Brazil
| | - Amanda P Nunes
- Biotechnology Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Emerson S Bernardes
- Radiopharmacy Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Sofia N dos Santos
- Radiopharmacy Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Fábio F A da Silva
- Radiopharmacy Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Cibele N Peroni
- Biotechnology Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - João E Oliveira
- Biotechnology Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Rosemary S E Brown
- Department of Physiology, Centre for Neuroendocrinology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Gimena Fernandez
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, La Plata, BA 1900, Argentina
| | - Pablo N De Francesco
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, La Plata, BA 1900, Argentina
| | - Mario Perelló
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, La Plata, BA 1900, Argentina
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, Uppsala 75312, Sweden
| | - Carlos R J Soares
- Biotechnology Center, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo 05508-000, Brazil
| | - Jose Donato
- Departamento de Fisiologia e Biofísica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Brazil
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6
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Raise-Abdullahi P, Meamar M, Vafaei AA, Alizadeh M, Dadkhah M, Shafia S, Ghalandari-Shamami M, Naderian R, Afshin Samaei S, Rashidy-Pour A. Hypothalamus and Post-Traumatic Stress Disorder: A Review. Brain Sci 2023; 13:1010. [PMID: 37508942 PMCID: PMC10377115 DOI: 10.3390/brainsci13071010] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/25/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
Humans have lived in a dynamic environment fraught with potential dangers for thousands of years. While fear and stress were crucial for the survival of our ancestors, today, they are mostly considered harmful factors, threatening both our physical and mental health. Trauma is a highly stressful, often life-threatening event or a series of events, such as sexual assault, war, natural disasters, burns, and car accidents. Trauma can cause pathological metaplasticity, leading to long-lasting behavioral changes and impairing an individual's ability to cope with future challenges. If an individual is vulnerable, a tremendously traumatic event may result in post-traumatic stress disorder (PTSD). The hypothalamus is critical in initiating hormonal responses to stressful stimuli via the hypothalamic-pituitary-adrenal (HPA) axis. Linked to the prefrontal cortex and limbic structures, especially the amygdala and hippocampus, the hypothalamus acts as a central hub, integrating physiological aspects of the stress response. Consequently, the hypothalamic functions have been attributed to the pathophysiology of PTSD. However, apart from the well-known role of the HPA axis, the hypothalamus may also play different roles in the development of PTSD through other pathways, including the hypothalamic-pituitary-thyroid (HPT) and hypothalamic-pituitary-gonadal (HPG) axes, as well as by secreting growth hormone, prolactin, dopamine, and oxytocin. This review aims to summarize the current evidence regarding the neuroendocrine functions of the hypothalamus, which are correlated with the development of PTSD. A better understanding of the role of the hypothalamus in PTSD could help develop better treatments for this debilitating condition.
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Affiliation(s)
| | - Morvarid Meamar
- Research Center of Physiology, Semnan University of Medical Sciences, Semnan, Iran
| | - Abbas Ali Vafaei
- Research Center of Physiology, Semnan University of Medical Sciences, Semnan, Iran
- Department of Physiology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Maryam Alizadeh
- Department of Basic Medical Sciences, Faculty of Medicine, Qom Medical Sciences, Islamic Azad University, Qom, Iran
| | - Masoomeh Dadkhah
- Pharmaceutical Sciences Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Sakineh Shafia
- Immunogenetics Research Center, Department of Physiology, Mazandaran University of Medical Sciences, Sari, Iran
| | | | - Ramtin Naderian
- Student Research Committee, Semnan University of Medical Sciences, Semnan, Iran
| | - Seyed Afshin Samaei
- Department of Neurology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Ali Rashidy-Pour
- Research Center of Physiology, Semnan University of Medical Sciences, Semnan, Iran
- Department of Physiology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
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7
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Wasinski F, Tavares MR, Gusmao DO, List EO, Kopchick JJ, Alves GA, Frazao R, Donato J. Central growth hormone action regulates neuroglial and proinflammatory markers in the hypothalamus of male mice. Neurosci Lett 2023; 806:137236. [PMID: 37030549 PMCID: PMC10133206 DOI: 10.1016/j.neulet.2023.137236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 04/10/2023]
Abstract
Growth hormone (GH) action in specific neuronal populations regulates neuroendocrine responses, metabolism, and behavior. However, the potential role of central GH action on glial function is less understood. The present study aims to determine how the hypothalamic expression of several neuroglial markers is affected by central GH action in male mice. The dwarf GH- and insulin-like growth factor-1 (IGF-1)-deficient Ghrhrlit/lit mice showed decreased mRNA expression of Nes (Nestin), Gfap, Iba1, Adgre1 (F4/80), and Tnf (TNFα) in the hypothalamus, compared to wild-type animals. In contrast, transgenic overexpression of GH led to high serum GH and IGF-1 levels, and increased hypothalamic expression of Nes, Gfap, Adgre1, Iba1, and Rax. Hepatocyte-specific GH receptor (GHR) knockout mice, which are characterized by high serum GH levels, but reduced IGF-1 secretion, showed increased mRNA expression of Gfap, Iba1, Tnf, and Sox10, demonstrating that the increase in GH levels alters the hypothalamic expression of glial markers associated with neuroinflammation, independently of IGF-1. Conversely, brain-specific GHR knockout mice showed reduced expression of Gfap, Adgre1, and Vim (vimentin), indicating that brain GHR signaling is necessary to mediate GH-induced changes in the expression of several neuroglial markers. In conclusion, the hypothalamic mRNA levels of several neuroglial markers associated with inflammation are directly modulated by GHR signaling in male mice.
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Affiliation(s)
- Frederick Wasinski
- Department of Neurology and Neurosurgery, Universidade Federal de Sao Paulo, Sao Paulo, SP 04039-032, Brazil
| | - Mariana R Tavares
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Daniela O Gusmao
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Guilherme A Alves
- Department of Anatomy, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-900, Brazil
| | - Renata Frazao
- Department of Anatomy, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-900, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil.
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8
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dos Santos WO, Wasinski F, Tavares MR, Campos AMP, Elias CF, List EO, Kopchick JJ, Szawka RE, Donato J. Ablation of Growth Hormone Receptor in GABAergic Neurons Leads to Increased Pulsatile Growth Hormone Secretion. Endocrinology 2022; 163:6634255. [PMID: 35803590 PMCID: PMC9302893 DOI: 10.1210/endocr/bqac103] [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: 12/27/2021] [Indexed: 11/19/2022]
Abstract
Growth hormone (GH) acts in several hypothalamic neuronal populations to modulate metabolism and the autoregulation of GH secretion via negative-feedback loops. However, few studies have investigated whether GH receptor (GHR) expression in specific neuronal populations is required for the homeostatic control of GH secretion and energy homeostasis. In the present study, we investigated the consequences of the specific GHR ablation in GABAergic (VGAT-expressing) or glutamatergic (VGLUT2-expressing) cells. GHR ablation in GABAergic neurons led to increased GH secretion, lean mass, and body growth in male and female mice. VGAT-specific GHR knockout (KO) male mice also showed increased serum insulin-like growth factor-1, hypothalamic Ghrh, and hepatic Igf1 messenger RNA levels. In contrast, normal GH secretion, but reduced lean body mass, was observed in mice carrying GHR ablation in glutamatergic neurons. GHR ablation in GABAergic cells increased weight loss and led to decreased blood glucose levels during food restriction, whereas VGLUT2-specific GHR KO mice showed blunted feeding response to 2-deoxy-D-glucose both in males and females, and increased relative food intake, oxygen consumption, and serum leptin levels in male mice. Of note, VGLUT2-cre female mice, independently of GHR ablation, exhibited a previously unreported phenotype of mild reduction in body weight without further metabolic alterations. The autoregulation of GH secretion via negative-feedback loops requires GHR expression in GABAergic cells. Furthermore, GHR ablation in GABAergic and glutamatergic neuronal populations leads to distinct metabolic alterations. These findings contribute to the understanding of the neuronal populations responsible for mediating the neuroendocrine and metabolic effects of GH.
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Affiliation(s)
- Willian O dos Santos
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, 05508-000, Brazil
| | - Frederick Wasinski
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, 05508-000, Brazil
| | - Mariana R Tavares
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, 05508-000, Brazil
| | - Ana M P Campos
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, 05508-000, Brazil
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, 48109-5622, USA
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, 45701, USA
| | - Raphael E Szawka
- Department of Physiology and Biophysics, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Jose Donato
- Correspondence: Jose Donato Jr, PhD, Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, Av. Prof Lineu Prestes, 1524, São Paulo, 05508-000, Brazil.
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9
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Wasinski F, Teixeira PDS, List EO, Kopchick JJ, Donato J. Growth hormone receptor contributes to the activation of STAT5 in the hypothalamus of pregnant mice. Neurosci Lett 2021; 770:136402. [PMID: 34929316 DOI: 10.1016/j.neulet.2021.136402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/03/2021] [Accepted: 12/14/2021] [Indexed: 11/19/2022]
Abstract
Growth hormone (GH) receptor (GHR) signaling induces the phosphorylation of the signal transducer and activator of transcription 5 (pSTAT5) in the cells of several tissues including in the hypothalamus. During pregnancy, several STAT5-recruiting hormones (e.g., prolactin, GH and placental lactogens) are highly secreted. However, the precise contribution of GHR signaling to the surge of pSTAT5 immunoreactive neurons that occurs in the hypothalamus of pregnant mice is currently unknown. Thus, the objective of the present study was to determine whether GHR expression in neurons is required for inducing pSTAT5 expression in several hypothalamic nuclei during pregnancy. Initially, we demonstrated that late pregnant C57BL/6 mice (gestational day 14 to 18) exhibited increased pulsatile GH secretion compared to virgin females. Next, we confirmed that neuron-specific GHR ablation robustly reduces hypothalamic Ghr mRNA levels and prevents GH-induced pSTAT5 in the arcuate, paraventricular and ventromedial hypothalamic nuclei. Subsequently, the number of pSTAT5 immunoreactive cells was determined in the hypothalamus of late pregnant mice. Although neuron-specific GHR ablation did not affect the number of pSTAT5 immunoreactive cells in the paraventricular nucleus of the hypothalamus, reduced pSTAT5 expression was observed in the arcuate and ventromedial nuclei of pregnant neuron-specific GHR knockouts, compared to control pregnant mice. In summary, a subset of hypothalamic neurons requires GHR signaling to express pSTAT5 during pregnancy. These findings contribute to the understanding of the endocrine factors that affect the activation of transcription factors in the brain during pregnancy.
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Affiliation(s)
- Frederick Wasinski
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofísica, Sao Paulo 05508000, Brazil
| | - Pryscila D S Teixeira
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofísica, Sao Paulo 05508000, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Jose Donato
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofísica, Sao Paulo 05508000, Brazil.
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10
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dos Santos WO, Gusmao DO, Wasinski F, List EO, Kopchick JJ, Donato J. Effects of Growth Hormone Receptor Ablation in Corticotropin-Releasing Hormone Cells. Int J Mol Sci 2021; 22:9908. [PMID: 34576072 PMCID: PMC8465163 DOI: 10.3390/ijms22189908] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 01/11/2023] Open
Abstract
Corticotropin-releasing hormone (CRH) cells are the dominant neuronal population responsive to the growth hormone (GH) in the paraventricular nucleus of the hypothalamus (PVH). However, the physiological importance of GH receptor (GHR) signaling in CRH neurons is currently unknown. Thus, the main objective of the present study was to investigate the consequences of GHR ablation in CRH-expressing cells of male and female mice. GHR ablation in CRH cells did not cause significant changes in body weight, body composition, food intake, substrate oxidation, locomotor activity, glucose tolerance, insulin sensitivity, counterregulatory response to 2-deoxy-D-glucose and ghrelin-induced food intake. However, reduced energy expenditure was observed in female mice carrying GHR ablation in CRH cells. The absence of GHR in CRH cells did not affect anxiety, circadian glucocorticoid levels or restraint-stress-induced corticosterone secretion and activation of PVH neurons in both male and female mice. In summary, GHR ablation, specifically in CRH-expressing neurons, does not lead to major alterations in metabolism, hypothalamic-pituitary-adrenal axis, acute stress response or anxiety in mice. Considering the previous studies showing that central GHR signaling regulates homeostasis in situations of metabolic stress, future studies are still necessary to identify the potential physiological importance of GH action on CRH neurons.
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Affiliation(s)
- Willian O. dos Santos
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (W.O.d.S.); (D.O.G.); (F.W.)
| | - Daniela O. Gusmao
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (W.O.d.S.); (D.O.G.); (F.W.)
| | - Frederick Wasinski
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (W.O.d.S.); (D.O.G.); (F.W.)
| | - Edward O. List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA; (E.O.L.); (J.J.K.)
| | - John J. Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA; (E.O.L.); (J.J.K.)
| | - Jose Donato
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (W.O.d.S.); (D.O.G.); (F.W.)
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