1
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Brie B, Sarmento-Cabral A, Pascual F, Cordoba-Chacon J, Kineman RD, Becu-Villalobos D. Modifications of the GH Axis Reveal Unique Sexually Dimorphic Liver Signatures for Lcn13, Asns, Hamp2, Hao2, and Pgc1a. J Endocr Soc 2024; 8:bvae015. [PMID: 38370444 PMCID: PMC10872697 DOI: 10.1210/jendso/bvae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Indexed: 02/20/2024] Open
Abstract
Growth hormone (GH) modifies liver gene transcription in a sexually dimorphic manner to meet liver metabolic demands related to sex; thus, GH dysregulation leads to sex-biased hepatic disease. We dissected the steps of the GH regulatory cascade modifying GH-dependent genes involved in metabolism, focusing on the male-predominant genes Lcn13, Asns, and Cyp7b1, and the female-predominant genes Hao2, Pgc1a, Hamp2, Cyp2a4, and Cyp2b9. We explored mRNA expression in 2 settings: (i) intact liver GH receptor (GHR) but altered GH and insulin-like growth factor 1 (IGF1) levels (NeuroDrd2KO, HiGH, aHepIGF1kd, and STAT5bCA mouse lines); and (ii) liver loss of GHR, with or without STAT5b reconstitution (aHepGHRkd, and aHepGHRkd + STAT5bCA). Lcn13 was downregulated in males in most models, while Asns and Cyp7b1 were decreased in males by low GH levels or action, or constant GH levels, but unexpectedly upregulated in both sexes by the loss of liver Igf1 or constitutive Stat5b expression. Hao, Cyp2a4, and Cyp2b9 were generally decreased in female mice with low GH levels or action (NeuroDrd2KO and/or aHepGHRkd mice) and increased in HiGH females, while in contrast, Pgc1a was increased in female NeuroDrd2KO but decreased in STAT5bCA and aHepIGF1kd females. Bioinformatic analysis of RNAseq from aHepGHRkd livers stressed the greater impact of GHR loss on wide gene expression in males and highlighted that GH modifies almost completely different gene signatures in each sex. Concordantly, we show that altering different steps of the GH cascade in the liver modified liver expression of Lcn13, Asns, Cyp7b1, Hao2, Hamp2, Pgc1a, Cyp2a4, and Cyp2b9 in a sex- and gene-specific manner.
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Affiliation(s)
- Belen Brie
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
| | - Andre Sarmento-Cabral
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Florencia Pascual
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
| | - Jose Cordoba-Chacon
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Rhonda Denise Kineman
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA
| | - Damasia Becu-Villalobos
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
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2
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de Sousa ME, Gusmao DO, Dos Santos WO, Moriya HT, de Lima FF, List EO, Kopchick JJ, Donato J. Fasting and prolonged food restriction differentially affect GH secretion independently of GH receptor signaling in AgRP neurons. J Neuroendocrinol 2023:e13254. [PMID: 36964750 DOI: 10.1111/jne.13254] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/14/2023]
Abstract
Growth hormone (GH) receptor (GHR) is abundantly expressed in neurons that co-release the agouti-related protein (AgRP) and neuropeptide Y (NPY) in the arcuate nucleus of the hypothalamus (ARH). Since ARHAgRP/NPY neurons regulate several hypothalamic-pituitary-endocrine axes, this neuronal population possibly modulates GH secretion via a negative feedback loop, particularly during food restriction, when ARHAgRP/NPY neurons are highly active. The present study aims to determine the importance of GHR signaling in ARHAgRP/NPY neurons on the pattern of GH secretion in fed and food-deprived male mice. Additionally, we compared the effect of two distinct situations of food deprivation: 16 h of fasting or four days of food restriction (40% of usual food intake). Overnight fasting strongly suppressed both basal and pulsatile GH secretion. Animals lacking GHR in ARHAgRP/NPY neurons (AgRP∆GHR mice) did not exhibit differences in GH secretion either in the fed or fasted state, compared to control mice. In contrast, four days of food restriction increased GH pulse frequency, basal GH secretion, and pulse irregularity/complexity (measured by sample entropy), whereas pulsatile GH secretion was not affected in both control and AgRP∆GHR mice. Hypothalamic Ghrh mRNA levels were unaffected by fasting or food restriction, but Sst expression increased in acutely fasted mice, but decreased after prolonged food restriction in both control and AgRP∆GHR mice. Our findings indicate that short-term fasting and prolonged food restriction differentially affect the pattern of GH secretion, independently of GHR signaling in ARHAgRP/NPY neurons.
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Affiliation(s)
- Maria E de Sousa
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Daniela O Gusmao
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Willian O Dos Santos
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Henrique T Moriya
- Biomedical Engineering Laboratory, Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, 05508-010, Brazil
| | - Felipe F de Lima
- Biomedical Engineering Laboratory, Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, 05508-010, Brazil
| | - 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
| | - Jose Donato
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
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3
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Gusmao DO, de Sousa ME, Tavares MR, Donato J. Increased GH Secretion and Body Growth in Mice Carrying Ablation of IGF-1 Receptor in GH-releasing Hormone Cells. Endocrinology 2022; 163:6696879. [PMID: 36099517 DOI: 10.1210/endocr/bqac151] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Indexed: 11/19/2022]
Abstract
Growth hormone (GH) secretion is controlled by short and long negative feedback loops. In this regard, both GH (short-loop feedback) and insulin-like growth factor 1 (IGF-1; long-loop feedback) can target somatotropic cells of the pituitary gland and neuroendocrine hypothalamic neurons to regulate the GH/IGF-1 axis. GH-releasing hormone (GHRH)-expressing neurons play a fundamental role in stimulating pituitary GH secretion. However, it is currently unknown whether IGF-1 action on GHRH-expressing cells is required for the control of the GH/IGF-1/growth axis. In the present study, we investigated the phenotype of male and female mice carrying ablation of IGF-1 receptor (IGF1R) exclusively in GHRH cells. After weaning, both male and female GHRHΔIGF1R mice exhibited increases in body weight, lean body mass, linear growth, and length of long bones (tibia, femur, humerus, and radius). In contrast, the percentage of body fat was similar between control and GHRHΔIGF1R mice. The higher body growth of GHRHΔIGF1R mice can be explained by increases in mean GH levels, GH pulse amplitude, and pulse frequency, calculated from 36 blood samples collected from each animal at 10-minute intervals. GHRHΔIGF1R mice also showed increased hypothalamic Ghrh mRNA levels, pituitary Gh mRNA expression, hepatic Igf1 expression, and serum IGF-1 levels compared with control animals. Furthermore, GHRHΔIGF1R mice displayed significant alterations in the sexually dimorphic hepatic gene expression profile, with a prevailing feminization in most genes analyzed. In conclusion, our findings indicate that GHRH neurons represent a key and necessary site for the long-loop negative feedback that controls the GH/IGF-1 axis and body growth.
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Affiliation(s)
- Daniela O Gusmao
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Maria E de Sousa
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Mariana R Tavares
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, 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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4
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Chaves FM, Wasinski F, Tavares MR, Mansano NS, Frazao R, Gusmao DO, Quaresma PGF, Pedroso JAB, Elias CF, List EO, Kopchick JJ, Szawka RE, Donato J. Effects of the Isolated and Combined Ablation of Growth Hormone and IGF-1 Receptors in Somatostatin Neurons. Endocrinology 2022; 163:6565600. [PMID: 35395079 PMCID: PMC9070500 DOI: 10.1210/endocr/bqac045] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Indexed: 11/19/2022]
Abstract
Hypophysiotropic somatostatin (SST) neurons in the periventricular hypothalamic area express growth hormone (GH) receptor (GHR) and are frequently considered as the key neuronal population that mediates the negative feedback loop controlling the hypothalamic-GH axis. Additionally, insulin-like growth factor-1 (IGF-1) may also act at the hypothalamic level to control pituitary GH secretion via long-loop negative feedback. However, to the best of our knowledge, no study so far has tested whether GHR or IGF-1 receptor (IGF1R) signaling specifically in SST neurons is required for the homeostatic control of GH secretion. Here we show that GHR ablation in SST neurons did not impact the negative feedback mechanisms that control pulsatile GH secretion or body growth in male and female mice. The sex difference in hepatic gene expression profile was only mildly affected by GHR ablation in SST neurons. Similarly, IGF1R ablation in SST neurons did not affect pulsatile GH secretion, body growth, or hepatic gene expression. In contrast, simultaneous ablation of both GHR and IGF1R in SST-expressing cells increased mean GH levels and pulse amplitude in male and female mice, and partially disrupted the sex differences in hepatic gene expression. Despite the increased GH secretion in double knockout mice, no alterations in body growth and serum or liver IGF-1 levels were observed. In summary, GHR and IGF1R signaling in SST neurons play a redundant role in the control of GH secretion. Furthermore, our results reveal the importance of GH/IGF-1 negative feedback mechanisms on SST neurons for the establishment of sex differences in hepatic gene expression profile.
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Affiliation(s)
- Fernanda M Chaves
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - Frederick Wasinski
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - Mariana R Tavares
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - Naira S Mansano
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-900, Brazil
| | - Renata Frazao
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-900, Brazil
| | - Daniela O Gusmao
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - Paula G F Quaresma
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - João A B Pedroso
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109-5622, USA
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701USA
| | - 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
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, 05508-000, Brazil
- Correspondence: Jose Donato Jr, PhD, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508000, Brazil.
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5
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Qian Y, Berryman DE, Basu R, List EO, Okada S, Young JA, Jensen EA, Bell SRC, Kulkarni P, Duran-Ortiz S, Mora-Criollo P, Mathes SC, Brittain AL, Buchman M, Davis E, Funk KR, Bogart J, Ibarra D, Mendez-Gibson I, Slyby J, Terry J, Kopchick JJ. Mice with gene alterations in the GH and IGF family. Pituitary 2022; 25:1-51. [PMID: 34797529 PMCID: PMC8603657 DOI: 10.1007/s11102-021-01191-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/21/2021] [Indexed: 01/04/2023]
Abstract
Much of our understanding of GH's action stems from animal models and the generation and characterization of genetically altered or modified mice. Manipulation of genes in the GH/IGF1 family in animals started in 1982 when the first GH transgenic mice were produced. Since then, multiple laboratories have altered mouse DNA to globally disrupt Gh, Ghr, and other genes upstream or downstream of GH or its receptor. The ability to stay current with the various genetically manipulated mouse lines within the realm of GH/IGF1 research has been daunting. As such, this review attempts to consolidate and summarize the literature related to the initial characterization of many of the known gene-manipulated mice relating to the actions of GH, PRL and IGF1. We have organized the mouse lines by modifications made to constituents of the GH/IGF1 family either upstream or downstream of GHR or to the GHR itself. Available data on the effect of altered gene expression on growth, GH/IGF1 levels, body composition, reproduction, diabetes, metabolism, cancer, and aging are summarized. For the ease of finding this information, key words are highlighted in bold throughout the main text for each mouse line and this information is summarized in Tables 1, 2, 3 and 4. Most importantly, the collective data derived from and reported for these mice have enhanced our understanding of GH action.
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Affiliation(s)
- Yanrong Qian
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Reetobrata Basu
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Edward O List
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Shigeru Okada
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Pediatrics, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Jonathan A Young
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Elizabeth A Jensen
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- Translational Biomedical Sciences Doctoral Program, Ohio University, Athens, OH, USA
| | - Stephen R C Bell
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Prateek Kulkarni
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | | | - Patricia Mora-Criollo
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Translational Biomedical Sciences Doctoral Program, Ohio University, Athens, OH, USA
| | - Samuel C Mathes
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Alison L Brittain
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Mat Buchman
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Emily Davis
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Kevin R Funk
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Jolie Bogart
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Diego Ibarra
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Chemistry and Biochemistry, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Isaac Mendez-Gibson
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- College of Health Sciences and Professions, Ohio University, Athens, OH, USA
| | - Julie Slyby
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Joseph Terry
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA.
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
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6
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Qian X, Wang T, Gong J, Wang L, Chen X, Lin H, Tu W, Jiang S, Li S. Exercise in mice ameliorates high-fat diet-induced nonalcoholic fatty liver disease by lowering HMGCS2. Aging (Albany NY) 2021; 13:8960-8974. [PMID: 33647884 PMCID: PMC8034885 DOI: 10.18632/aging.202717] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/14/2021] [Indexed: 12/18/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. Exercise is a therapeutic strategy for preventing NAFLD. However, the underlying molecular mechanisms by which NAFLD can be ameliorated through exercise are still not clear. This study investigates the mechanisms by which exercise suppresses NAFLD development induced by a high-fat diet (HFD) in mice. Male 6-week-old C57BL/6J mice were fed a normal diet or HFD for 12 weeks and then induced to swim or remain sedentary for 8 weeks. Histomorphology, inflammatory factors, fat metabolizing enzymes, fibrosis, and steatosis were determined in HFD-fed mouse liver, and levels of hepatic enzymes and molecules in the related pathways were analyzed. NAFLD mice showed evident steatosis, fibrosis, and liver injury, and an increased expression of HMGCS2, Wnt3a/ β-catenin, and phosphorylated (p)-AMPK in the liver. Exercise significantly attenuated these symptoms and downregulated the level of Wnt3a/β-catenin in lipotoxic liver tissue. Inhibition of HMGCS2 expression decreased the activation of the Wnt3a/β-catenin pathway and lowered p-AMPK in palmitate-treated HepG2. Our results suggest that exercise prevents NAFLD-associated liver injury, steatosis, and fibrosis. Exercise-mediated hepatoprotection was achieved partly via the blocking of the upregulation of HMGCS2 and the attenuation of the Wnt3a/β-catenin pathway.
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Affiliation(s)
- Xiaoli Qian
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Ting Wang
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Jiahong Gong
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Li Wang
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Xuyan Chen
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Haiyan Lin
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Wenzhan Tu
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Songhe Jiang
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Shengcun Li
- Rehabilitation Medicine Center, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.,Integrative and Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
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7
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Sarmento-Cabral A, del Rio-Moreno M, Vazquez-Borrego MC, Mahmood M, Gutierrez-Casado E, Pelke N, Guzman G, Subbaiah PV, Cordoba-Chacon J, Yakar S, Kineman RD. GH directly inhibits steatosis and liver injury in a sex-dependent and IGF1-independent manner. J Endocrinol 2021; 248:31-44. [PMID: 33112796 PMCID: PMC7785648 DOI: 10.1530/joe-20-0326] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022]
Abstract
A reduction in hepatocyte growth hormone (GH)-signaling promotes non-alcoholic fatty liver disease (NAFLD). However, debate remains as to the relative contribution of the direct effects of GH on hepatocyte function vs indirect effects, via alterations in insulin-like growth factor 1 (IGF1). To isolate the role of hepatocyte GH receptor (GHR) signaling, independent of changes in IGF1, mice with adult-onset, hepatocyte-specific GHR knockdown (aHepGHRkd) were treated with a vector expressing rat IGF1 targeted specifically to hepatocytes. Compared to GHR-intact mice, aHepGHRkd reduced circulating IGF1 and elevated GH. In male aHepGHRkd, the shift in IGF1/GH did not alter plasma glucose or non-esterified fatty acids (NEFA), but was associated with increased insulin, enhanced systemic lipid oxidation and reduced white adipose tissue (WAT) mass. Livers of male aHepGHRkd exhibited steatosis associated with increased de novo lipogenesis, hepatocyte ballooning and inflammation. In female aHepGHRkd, hepatic GHR protein levels were not detectable, but moderate levels of IGF1 were maintained, with minimal alterations in systemic metabolism and no evidence of steatosis. Reconstitution of hepatocyte IGF1 in male aHepGHRkd lowered GH and normalized insulin, whole body lipid utilization and WAT mass. However, IGF1 reconstitution did not reduce steatosis or eliminate liver injury. RNAseq analysis showed IGF1 reconstitution did not impact aHepGHRkd-induced changes in liver gene expression, despite changes in systemic metabolism. These results demonstrate the impact of aHepGHRkd is sexually dimorphic and the steatosis and liver injury observed in male aHepGHRkd mice is autonomous of IGF1, suggesting GH acts directly on the adult hepatocyte to control NAFLD progression.
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Affiliation(s)
- Andre Sarmento-Cabral
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mercedes del Rio-Moreno
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mari C. Vazquez-Borrego
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mariyah Mahmood
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Elena Gutierrez-Casado
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Natalie Pelke
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Grace Guzman
- Department of Pathology, University of Illinois at Chicago,
College of Medicine, Chicago, IL
| | - Papasani V. Subbaiah
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Jose Cordoba-Chacon
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Shoshana Yakar
- Department of Molecular Pathobiology, New York University
College of Dentistry, New York, NY
| | - Rhonda D. Kineman
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
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8
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Tyrosine Hydroxylase Neurons Regulate Growth Hormone Secretion via Short-Loop Negative Feedback. J Neurosci 2020; 40:4309-4322. [PMID: 32317389 DOI: 10.1523/jneurosci.2531-19.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 02/07/2023] Open
Abstract
Classical studies suggest that growth hormone (GH) secretion is controlled by negative-feedback loops mediated by GH-releasing hormone (GHRH)- or somatostatin-expressing neurons. Catecholamines are known to alter GH secretion and neurons expressing TH are located in several brain areas containing GH-responsive cells. However, whether TH-expressing neurons are required to regulate GH secretion via negative-feedback mechanisms is unknown. In the present study, we showed that between 50% and 90% of TH-expressing neurons in the periventricular, paraventricular, and arcuate hypothalamic nuclei and locus ceruleus of mice exhibited STAT5 phosphorylation (pSTAT5) after an acute GH injection. Ablation of GH receptor (GHR) from TH cells or in the entire brain markedly increased GH pulse secretion and body growth in both male and female mice. In contrast, GHR ablation in cells that express the dopamine transporter (DAT) or dopamine β-hydroxylase (DBH; marker of noradrenergic/adrenergic cells) did not affect body growth. Nevertheless, less than 50% of TH-expressing neurons in the hypothalamus were found to express DAT. Ablation of GHR in TH cells increased the hypothalamic expression of Ghrh mRNA, although very few GHRH neurons were found to coexpress TH- and GH-induced pSTAT5. In summary, TH neurons that do not express DAT or DBH are required for the autoregulation of GH secretion via a negative-feedback loop. Our findings revealed a critical and previously unidentified group of catecholaminergic interneurons that are apt to sense changes in GH levels and regulate the somatotropic axis in mice.SIGNIFICANCE STATEMENT Textbooks indicate until now that the pulsatile pattern of growth hormone (GH) secretion is primarily controlled by GH-releasing hormone and somatostatin neurons. The regulation of GH secretion relies on the ability of these cells to sense changes in circulating GH levels to adjust pituitary GH secretion within a narrow physiological range. However, our study identifies a specific population of tyrosine hydroxylase-expressing neurons that is critical to autoregulate GH secretion via a negative-feedback loop. The lack of this mechanism in transgenic mice results in aberrant GH secretion and body growth. Since GH plays a key role in cell proliferation, body growth, and metabolism, our findings provide a major advance to understand how the brain regulates the somatotropic axis.
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Herrera-Martínez AD, Pedraza-Arevalo S, L-López F, Gahete MD, Gálvez-Moreno MA, Castaño JP, Luque RM. Type 2 Diabetes in Neuroendocrine Tumors: Are Biguanides and Statins Part of the Solution? J Clin Endocrinol Metab 2019; 104:57-73. [PMID: 30265346 DOI: 10.1210/jc.2018-01455] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 09/24/2018] [Indexed: 12/13/2022]
Abstract
CONTEXT Biguanides and statins exert beneficial effects on various cancer types. Their precise effects and underlying molecular mechanisms are poorly understood. MATERIALS AND METHODS We analyzed the relationship between metabolic syndrome and histological, epidemiological, and prognosis variables in two cohorts of patients with neuroendocrine tumors (NETs): those with lung carcinoids (LCs; n = 81) and those with gastroenteropancreatic NET (GEP-NET; n = 100). Biguanide and statin antitumor effects were investigated by evaluating proliferation, migration, secretion, gene expression, and involved molecular pathways in BON1/QGP1 cell cultures. RESULTS Pleura invasion was higher (LCs group; P < 0.05) and tumor diameter tended to be increased (GEP-NET group) in patients with type 2 diabetes (T2DM) than in those without. Somatostatin and ghrelin systems mRNA levels differed in tumor tissue of patients with T2DM taking metformin or not. Biguanides decreased proliferation rate in BON1/QGP1 cells; the effects of statins on proliferation rate depended on the statin and cell types, and time. Specifically, only simvastatin and atorvastatin decreased proliferation in BON1 cells, whereas all statins decreased proliferation rate in QGP1 cells. Metformin and simvastatin decreased migration capacity in BON1 cells; biguanides decreased serotonin secretion in BON1 cells. Phenformin increased apoptosis in BON1/QGP1 cells; simvastatin increased apoptosis in QGP1 cells. These antitumor effects likely involved altered expression of key genes related to cancer aggressiveness. CONCLUSION A clear inhibitory effect of biguanides and statins was seen on NET-cell aggressiveness. Our results invite additional exploration of the potential therapeutic role of these drugs in treatment of patients with NETs.
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Affiliation(s)
- Aura D Herrera-Martínez
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Endocrinology and Nutrition Service, Reina Sofia University Hospital, Córdoba, Spain
| | - Sergio Pedraza-Arevalo
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
| | - Fernando L-López
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
| | - Manuel D Gahete
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
| | - María A Gálvez-Moreno
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Endocrinology and Nutrition Service, Reina Sofia University Hospital, Córdoba, Spain
| | - Justo P Castaño
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
| | - Raúl M Luque
- Maimonides Institute for Biomedical Research of Cordoba, Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
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10
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Cordoba-Chacon J, Sarmento-Cabral A, del Rio-Moreno M, Diaz-Ruiz A, Subbaiah PV, Kineman RD. Adult-Onset Hepatocyte GH Resistance Promotes NASH in Male Mice, Without Severe Systemic Metabolic Dysfunction. Endocrinology 2018; 159:3761-3774. [PMID: 30295789 PMCID: PMC6202859 DOI: 10.1210/en.2018-00669] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/01/2018] [Indexed: 12/20/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD), which includes nonalcoholic steatohepatitis (NASH), is associated with reduced GH input/signaling, and GH therapy is effective in the reduction/resolution of NAFLD/NASH in selected patient populations. Our laboratory has focused on isolating the direct vs indirect effects of GH in preventing NAFLD/NASH. We reported that chow-fed, adult-onset, hepatocyte-specific, GH receptor knockdown (aHepGHRkd) mice rapidly (within 7 days) develop steatosis associated with increased hepatic de novo lipogenesis (DNL), independent of changes in systemic metabolic function. In this study, we report that 6 months after induction of aHepGHRkd early signs of NASH develop, which include hepatocyte ballooning, inflammation, signs of mild fibrosis, and elevated plasma alanine aminotransferase. These changes occur in the presence of enhanced systemic lipid utilization, without evidence of white adipose tissue lipolysis, indicating that the liver injury that develops after aHepGHRkd is due to hepatocyte-specific loss of GH signaling and not due to secondary defects in systemic metabolic function. Specifically, enhanced hepatic DNL is sustained with age in aHepGHRkd mice, associated with increased hepatic markers of lipid uptake/re-esterification. Because hepatic DNL is a hallmark of NAFLD/NASH, these studies suggest that enhancing hepatocyte GH signaling could represent an effective therapeutic target to reduce DNL and treat NASH.
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Affiliation(s)
- Jose Cordoba-Chacon
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Andre Sarmento-Cabral
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Mercedes del Rio-Moreno
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC)/University of Cordoba, Cordoba, Spain
| | - Alberto Diaz-Ruiz
- Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
- Nutritional Interventions Group, Precision Nutrition and Aging, Institute IMDEA Food, Madrid, Spain
| | - Papasani V Subbaiah
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Rhonda D Kineman
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
- Correspondence: Rhonda D. Kineman, PhD, Jesse Brown Veterans Affairs Medical Center, Research and Development Division, 820 South Damen Avenue, Building 11A, Suite 6215, MP151, Chicago, Illinois 60612. E-mail:
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11
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Kineman RD, del Rio-Moreno M, Sarmento-Cabral A. 40 YEARS of IGF1: Understanding the tissue-specific roles of IGF1/IGF1R in regulating metabolism using the Cre/loxP system. J Mol Endocrinol 2018; 61:T187-T198. [PMID: 29743295 PMCID: PMC7721256 DOI: 10.1530/jme-18-0076] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 05/09/2018] [Indexed: 12/13/2022]
Abstract
It is clear that insulin-like growth factor-1 (IGF1) is important in supporting growth and regulating metabolism. The IGF1 found in the circulation is primarily produced by the liver hepatocytes, but healthy mature hepatocytes do not express appreciable levels of the IGF1 receptor (IGF1R). Therefore, the metabolic actions of IGF1 are thought to be mediated via extra-hepatocyte actions. Given the structural and functional homology between IGF1/IGF1R and insulin receptor (INSR) signaling, and the fact that IGF1, IGF1R and INSR are expressed in most tissues of the body, it is difficult to separate out the tissue-specific contributions of IGF1/IGF1R in maintaining whole body metabolic function. To circumvent this problem, over the last 20 years, investigators have taken advantage of the Cre/loxP system to manipulate IGF1/IGF1R in a tissue-dependent, and more recently, an age-dependent fashion. These studies have revealed that IGF1/IGF1R can alter extra-hepatocyte function to regulate hormonal inputs to the liver and/or alter tissue-specific carbohydrate and lipid metabolism to alter nutrient flux to liver, where these actions are not mutually exclusive, but serve to integrate the function of all tissues to support the metabolic needs of the organism.
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Affiliation(s)
- Rhonda D Kineman
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago,1819 W Polk St. M/C 646 Chicago, IL, 60612
- Research and Development Division, Jesse Brown VA Medical Center, Suite 6215, MP 191, 820 S Damen Ave. Chicago, IL 60612
- Corresponding author: Rhonda D Kineman, . University of Illinois at Chicago, Medicine, 1819 W. Polk St., MC 640, Chicago, IL, USA 60612
| | - Mercedes del Rio-Moreno
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago,1819 W Polk St. M/C 646 Chicago, IL, 60612
| | - André Sarmento-Cabral
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago,1819 W Polk St. M/C 646 Chicago, IL, 60612
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Abstract
Growth hormone (GH) secretory patterns emerge following birth, and changes in patterning occur throughout life. These secretory patterns are coupled to growth, reproduction and metabolism. Comparing human and animal studies, this review will highlight ultradian patterning of GH release and the mechanisms that contribute to this. Discussions will focus on the emergence in variations in the number and frequency of GH secretory events, and the amounts of GH released (peak and basal). Animal studies have contributed significantly to our understanding of the processes that regulate GH release. However, translation of knowledge from animal models to benefit our understanding of human physiology is sometimes limited. To overcome these limitations, it is critical that we reconcile the cause and consequences of differences in GH release between humans and model organisms. In doing so, we can embrace emerging technologies that will rapidly advance our knowledge of endogenous process that control GH release.
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Affiliation(s)
- Frederik J Steyn
- Centre for Clinical Research, The University of Queensland, Queensland, Australia; Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Australia.
| | - Shyuan T Ngo
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Australia; Queensland Brain Institute, The University of Queensland, Australia.
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13
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Cady G, Landeryou T, Garratt M, Kopchick JJ, Qi N, Garcia-Galiano D, Elias CF, Myers MG, Miller RA, Sandoval DA, Sadagurski M. Hypothalamic growth hormone receptor (GHR) controls hepatic glucose production in nutrient-sensing leptin receptor (LepRb) expressing neurons. Mol Metab 2017; 6:393-405. [PMID: 28462074 PMCID: PMC5404104 DOI: 10.1016/j.molmet.2017.03.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 02/28/2017] [Accepted: 03/04/2017] [Indexed: 12/22/2022] Open
Abstract
Objective The GH/IGF-1 axis has important roles in growth and metabolism. GH and GH receptor (GHR) are active in the central nervous system (CNS) and are crucial in regulating several aspects of metabolism. In the hypothalamus, there is a high abundance of GH-responsive cells, but the role of GH signaling in hypothalamic neurons is unknown. Previous work has demonstrated that the Ghr gene is highly expressed in LepRb neurons. Given that leptin is a key regulator of energy balance by acting on leptin receptor (LepRb)-expressing neurons, we tested the hypothesis that LepRb neurons represent an important site for GHR signaling to control body homeostasis. Methods To determine the importance of GHR signaling in LepRb neurons, we utilized Cre/loxP technology to ablate GHR expression in LepRb neurons (LeprEYFPΔGHR). The mice were generated by crossing the Leprcre on the cre-inducible ROSA26-EYFP mice to GHRL/L mice. Parameters of body composition and glucose homeostasis were evaluated. Results Our results demonstrate that the sites with GHR and LepRb co-expression include ARH, DMH, and LHA neurons. Leptin action was not altered in LeprEYFPΔGHR mice; however, GH-induced pStat5-IR in LepRb neurons was significantly reduced in these mice. Serum IGF-1 and GH levels were unaltered, and we found no evidence that GHR signaling regulates food intake and body weight in LepRb neurons. In contrast, diminished GHR signaling in LepRb neurons impaired hepatic insulin sensitivity and peripheral lipid metabolism. This was paralleled with a failure to suppress expression of the gluconeogenic genes and impaired hepatic insulin signaling in LeprEYFPΔGHR mice. Conclusion These findings suggest the existence of GHR-leptin neurocircuitry that plays an important role in the GHR-mediated regulation of glucose metabolism irrespective of feeding. GHR and LepRb are co-localized in the ARH, DMH and LHA neurons. GHR signaling does not regulate food intake and body weight in LepRb neurons. Diminished GHR signaling in LepRb neurons impairs hepatic glucose production.
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Key Words
- ARH, arcuate nucleus of the hypothalamus
- CNS, central nervous system
- DMH, dorsomedial hypothalamic nucleus
- GH, growth hormone
- GHR, growth hormone receptor
- Glucose production
- Growth hormone receptor
- Hypothalamus
- LHA, lateral hypothalamus
- Lepr, leptin receptor
- Leptin receptor
- Liver
- POMC, proopiomelanocortin
- PVH, paraventricular hypothalamic nucleus
- Stat3, signal transducer and activator of transcription 3
- Stat5, signal transducer and activator of transcription 5
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Affiliation(s)
- Gillian Cady
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Taylor Landeryou
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Michael Garratt
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Nathan Qi
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Martin G Myers
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Darleen A Sandoval
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Marianna Sadagurski
- Division of Geriatric and Palliative Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.
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14
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L-López F, Sarmento-Cabral A, Herrero-Aguayo V, Gahete MD, Castaño JP, Luque RM. Obesity and metabolic dysfunction severely influence prostate cell function: role of insulin and IGF1. J Cell Mol Med 2017; 21:1893-1904. [PMID: 28244645 PMCID: PMC5571563 DOI: 10.1111/jcmm.13109] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 01/01/2017] [Indexed: 12/13/2022] Open
Abstract
Obesity is a major health problem that courses with severe comorbidities and a drastic impairment of homeostasis and function of several organs, including the prostate gland (PG). The endocrine–metabolic regulatory axis comprising growth hormone (GH), insulin and IGF1, which is drastically altered under extreme metabolic conditions such as obesity, also plays relevant roles in the development, modulation and homeostasis of the PG. However, its implication in the pathophysiological interplay between obesity and prostate function is still to be elucidated. To explore this association, we used a high fat–diet obese mouse model, as well as in vitro primary cultures of normal‐mouse PG cells and human prostate cancer cell lines. This approach revealed that most of the components of the GH/insulin/IGF1 regulatory axis are present in PGs, where their expression pattern is altered under obesity conditions and after an acute insulin treatment (e.g. Igfbp3), which might have some pathophysiological implications. Moreover, our results demonstrate, for the first time, that the PG becomes severely insulin resistant under diet‐induced obesity in mice. Finally, use of in vitro approaches served to confirm and expand the conception that insulin and IGF1 play a direct, relevant role in the control of normal and pathological PG cell function. Altogether, these results uncover a fine, germane crosstalk between the endocrine–metabolic status and the development and homeostasis of the PG, wherein key components of the GH, insulin and IGF1 axes could play a relevant pathophysiological role.
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Affiliation(s)
- Fernando L-López
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
| | - André Sarmento-Cabral
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
| | - Vicente Herrero-Aguayo
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
| | - Manuel D Gahete
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
| | - Justo P Castaño
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
| | - Raúl M Luque
- Maimónides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.,Reina Sofía University Hospital, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain.,International Campus of Excellence on Agrifood, CeiA3, Cordoba, Spain
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15
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Obesity- and gender-dependent role of endogenous somatostatin and cortistatin in the regulation of endocrine and metabolic homeostasis in mice. Sci Rep 2016; 6:37992. [PMID: 27901064 PMCID: PMC5128804 DOI: 10.1038/srep37992] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 11/01/2016] [Indexed: 12/13/2022] Open
Abstract
Somatostatin (SST) and cortistatin (CORT) regulate numerous endocrine secretions and their absence [knockout (KO)-models] causes important endocrine-metabolic alterations, including pituitary dysregulations. We have demonstrated that the metabolic phenotype of single or combined SST/CORT KO-models is not drastically altered under normal conditions. However, the biological actions of SST/CORT are conditioned by the metabolic-status (e.g. obesity). Therefore, we used male/female SST- and CORT-KO mice fed low-fat (LF) or high-fat (HF) diet to explore the interplay between SST/CORT and obesity in the control of relevant pituitary-axes and whole-body metabolism. Our results showed that the SST/CORT role in the control of GH/prolactin secretions is maintained under LF- and HF-diet conditions as SST-KOs presented higher GH/prolactin-levels, while CORT-KOs displayed higher GH- and lower prolactin-levels than controls under both diets. Moreover, the impact of lack of SST/CORT on the metabolic-function was gender- and diet-dependent. Particularly, SST-KOs were more sensitive to HF-diet, exhibiting altered growth and body-composition (fat/lean percentage) and impaired glucose/insulin-metabolism, especially in males. Conversely, only males CORT-KO under LF-diet conditions exhibited significant alterations, displaying higher glucose-levels and insulin-resistance. Altogether, these data demonstrate a tight interplay between SST/CORT-axis and the metabolic status in the control of endocrine/metabolic functions and unveil a clear dissociation of SST/CORT roles.
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Romero CJ, Wolfe A, Law YY, Costelloe CZ, Miller R, Wondisford F, Radovick S. Altered somatotroph feedback regulation improves metabolic efficiency and limits adipose deposition in male mice. Metabolism 2016; 65:557-68. [PMID: 26975547 PMCID: PMC5331908 DOI: 10.1016/j.metabol.2015.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/18/2015] [Accepted: 11/25/2015] [Indexed: 11/22/2022]
Abstract
Several transgenic mouse models with disruption in the growth hormone (GH) axis support the role of GH in augmenting metabolic homeostasis. Specifically, interest has focused on GH's lipolytic properties and ability to affect adipose deposition. Furthermore, both GH and insulin growth factor 1 (IGF-1) may also play a direct or indirect role in adipose development. The somatotroph insulin-like growth factor-1 receptor knockout (SIGFRKO) mouse with only a modest increase in serum GH and IGF-1 demonstrates less adipose tissue than controls. In order to characterize the metabolic phenotype of SIGFRKO mice, histologic analysis of fat depots confirmed a smaller average diameter of adipocytes in the SIGFRKO mice compared to controls. These changes were accompanied by an increase in lipolytic gene expression in fat depots. Indirect calorimetry performed on 6-8week old male mice and again at 25weeks of age demonstrated that SIGFRKO mice, at both ages, had a higher VO2 and increased energy expenditure when compared with controls. The calculated respiratory exchange ratio (RER) was lower in the younger SIGFRKO mice compared to controls. No differences in food consumption or in either ambulatory or total activity were seen between SIGFRKO and control mice in either age group. These studies highlight the role of GH in adipose deposition and its influence on the expression of lipolytic genes resulting in an altered metabolic state, thus providing a mechanism for the decrease in weight gain seen in the SIGFRKO mouse model.
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Affiliation(s)
- Christopher J Romero
- Division of Pediatric Endocrinology and Diabetes, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1616, New York, NY 10029.
| | - Andrew Wolfe
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - Yi Ying Law
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - ChenChen Z Costelloe
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - Ryan Miller
- Division of Pediatric Endocrinology, University of Maryland Medical Center, 22. S. Greene St., Baltimore, MD 21201
| | - Fredric Wondisford
- Robert Wood Johnson Medical School, Rutgers Biomedical and Health Sciences, New Brunswick, NJ 08901
| | - Sally Radovick
- Robert Wood Johnson Medical School, Rutgers Biomedical and Health Sciences, New Brunswick, NJ 08901
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17
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Steyn FJ, Tolle V, Chen C, Epelbaum J. Neuroendocrine Regulation of Growth Hormone Secretion. Compr Physiol 2016; 6:687-735. [PMID: 27065166 DOI: 10.1002/cphy.c150002] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This article reviews the main findings that emerged in the intervening years since the previous volume on hormonal control of growth in the section on the endocrine system of the Handbook of Physiology concerning the intra- and extrahypothalamic neuronal networks connecting growth hormone releasing hormone (GHRH) and somatostatin hypophysiotropic neurons and the integration between regulators of food intake/metabolism and GH release. Among these findings, the discovery of ghrelin still raises many unanswered questions. One important event was the application of deconvolution analysis to the pulsatile patterns of GH secretion in different mammalian species, including Man, according to gender, hormonal environment and ageing. Concerning this last phenomenon, a great body of evidence now supports the role of an attenuation of the GHRH/GH/Insulin-like growth factor-1 (IGF-1) axis in the control of mammalian aging.
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Affiliation(s)
- Frederik J Steyn
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Virginie Tolle
- Unité Mixte de Recherche en Santé 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Jacques Epelbaum
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
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Cordoba-Chacon J, Majumdar N, Pokala NK, Gahete MD, Kineman RD. Islet insulin content and release are increased in male mice with elevated endogenous GH and IGF-I, without evidence of systemic insulin resistance or alterations in β-cell mass. Growth Horm IGF Res 2015; 25:189-195. [PMID: 25936582 DOI: 10.1016/j.ghir.2015.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 03/11/2015] [Accepted: 04/12/2015] [Indexed: 10/23/2022]
Abstract
UNLABELLED It is clear that elevations in circulating GH can lead to an increase in insulin levels. This increase in insulin may be due to GH-mediated insulin resistance and enhanced lipolysis. However, there is also in vitro and in vivo evidence that GH acts directly to increase β-cell proliferation and insulin production. Our laboratory recently developed an animal model with elevated endogenous GH levels associated with a small (25%), but significant, increase in IGF-I (HiGH mice). As expected, insulin levels were elevated in HiGH mice; however, whole body insulin sensitivity was not altered and glucose tolerance was improved. This metabolic phenotype suggests that modest elevations in circulating GH and IGF-I may enhance β-cell mass and/or function, in the absence of systemic insulin resistance, thus improving glucose homeostasis. OBJECTIVE To determine if β-cell mass and/or function is altered in HiGH mice. DESIGN Male HiGH mice and their littermate controls were fed a low-fat or high-fat diet. Body composition and circulating metabolic endpoints were monitored overtime. The pancreas was recovered and processed for assessment of β-cell mass or in vitro basal and glucose-stimulated insulin secretion. RESULTS HiGH mice showed elevated circulating insulin and normal glucose levels, while non-esterified FFA levels and triglycerides were reduced or normal, depending on diet and age. β-cell mass did not differ between HiGH and control mice, within diet. However, islets from HiGH mice contained and released more insulin under basal conditions, as compared to control islets, while the relative glucose-stimulated insulin release did not differ. CONCLUSIONS Taken together, these results suggest moderate elevations in circulating GH and IGF-I can directly increase basal insulin secretion without impacting β-cell mass, independent of changes in whole body insulin sensitivity and hyperlipidemia.
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Affiliation(s)
- Jose Cordoba-Chacon
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA; Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Neena Majumdar
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA; Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Naveen K Pokala
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA; Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Manuel D Gahete
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA; Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA; Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, 14014, Spain; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)/Hospital Universitario Reina Sofia, Córdoba, 14014, Spain; CIBER de la Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, 14014, Spain
| | - Rhonda D Kineman
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA; Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA.
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19
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Pedraza-Arévalo S, Córdoba-Chacón J, Pozo-Salas AI, L-López F, de Lecea L, Gahete MD, Castaño JP, Luque RM. Not So Giants: Mice Lacking Both Somatostatin and Cortistatin Have High GH Levels but Show No Changes in Growth Rate or IGF-1 Levels. Endocrinology 2015; 156:1958-64. [PMID: 25830706 DOI: 10.1210/en.2015-1132] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Somatostatin (SST) and cortistatin (CORT) are two highly related neuropeptides involved in the regulation of various endocrine secretions. In particular, SST and CORT are two primary negative regulators of GH secretion. Consequently, single SST or CORT knockout mice exhibit elevated GH levels; however, this does not lead to increased IGF-1 levels or somatic growth. This apparent lack of correspondence has been suggested to result from compensatory mechanisms between both peptides. To test this hypothesis, in this study we explored, for the first time, the consequences of simultaneously deleting endogenous SST and CORT by generating a double SST/CORT knockout mouse model and exploring its endocrine and metabolic phenotype. Our results demonstrate that simultaneous deletion of SST and CORT induced a drastic elevation of endogenous GH levels, which, surprisingly, did not lead to changes in growth rate or IGF-1 levels, suggesting the existence of additional factors/systems that, in the absence of endogenous SST and CORT, could counteract GH actions. Notably, elevation in circulating GH levels were not accompanied by changes in pituitary GH expression or by alterations in the expression of its main regulators (GHRH and ghrelin) or their receptors (GHRH receptor, GHS receptor, or SST/CORT receptors) at the hypothalamic or pituitary level. However, although double-SST/CORT knockout male mice exhibited normal glucose and insulin levels, they had improved insulin sensitivity compared with the control mice. Therefore, these results suggest the existence of an intricate interplay among the known (SST/CORT), and likely unknown, inhibitory components of the GH/IGF-1 axis to regulate somatic growth and glucose/insulin homeostasis.
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Affiliation(s)
- S Pedraza-Arévalo
- Department of Cell Biology, Physiology, and Immunology (S.P.-A., J.C.-C., A.I.P.-S., F.L.L., M.D.G., J.P.C., R.M.L.), University of Córdoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofía, and Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (CIBERObn), E-14014 Córdoba, Spain; Section of Endocrinology, Diabetes, and Metabolism (J.C.-C.), Department of Medicine (J.C.-C.), University of Illinois at Chicago, Chicago, Illinois 60637; Department of Research and Development, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois 60612; and Department of Psychiatry and Behavioral Sciences (L.d.L.), Stanford University, Stanford, California 94305
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20
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Ibáñez-Costa A, Gahete MD, Rivero-Cortés E, Rincón-Fernández D, Nelson R, Beltrán M, de la Riva A, Japón MA, Venegas-Moreno E, Gálvez MÁ, García-Arnés JA, Soto-Moreno A, Morgan J, Tsomaia N, Culler MD, Dieguez C, Castaño JP, Luque RM. In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features. Sci Rep 2015; 5:8714. [PMID: 25737012 PMCID: PMC4649711 DOI: 10.1038/srep08714] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 02/02/2015] [Indexed: 01/26/2023] Open
Abstract
Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas comparedwith normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24–72 h) increased GH and ACTH secretion, Ca2+ and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors.
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Affiliation(s)
- Alejandro Ibáñez-Costa
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Manuel D Gahete
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Esther Rivero-Cortés
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - David Rincón-Fernández
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | | | - Manuel Beltrán
- Department of Pathology, Puerta del Mar University Hospital, Cádiz
| | - Andrés de la Riva
- Service of Neurosurgery, Hospital Universitario Reina Sofia, 14004 Córdoba, Spain
| | - Miguel A Japón
- Department of Pathology, Hospital Universitario Virgen del Rocío, 41013 Seville, Spain
| | - Eva Venegas-Moreno
- Metabolism and Nutrition Unit, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla (IBIS), 41013 Seville, Spain
| | - Ma Ángeles Gálvez
- Service of Endocrinology and Nutrition, Hospital Universitario Reina Sofia, and Instituto Maimónides de Investigación Biomédica de Córdoba, 14004 Córdoba, Spain
| | - Juan A García-Arnés
- Department of Endocrinology and Nutrition, Carlos Haya Hospital, 29010 Málaga, Spain
| | - Alfonso Soto-Moreno
- Metabolism and Nutrition Unit, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla (IBIS), 41013 Seville, Spain
| | | | - Natia Tsomaia
- IPSEN Bioscience, Cambridge, 02142 Massachusetts, USA
| | | | - Carlos Dieguez
- Department of Physiology, University of Santiago de Compostela, and CIBER Fisiopatología de la Obesidad y Nutrición, 15782 Santiago de Compostela, Spain
| | - Justo P Castaño
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Raúl M Luque
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
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21
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Cordoba-Chacon J, Gahete MD, McGuinness OP, Kineman RD. Differential impact of selective GH deficiency and endogenous GH excess on insulin-mediated actions in muscle and liver of male mice. Am J Physiol Endocrinol Metab 2014; 307:E928-34. [PMID: 25269484 PMCID: PMC4233257 DOI: 10.1152/ajpendo.00420.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A reciprocal relationship between insulin sensitivity and glucose tolerance has been reported in some mouse models and humans with isolated changes in growth hormone (GH) production and signaling. To determine if this could be explained in part by tissue-specific changes in insulin sensitivity, hyperinsulinemic-euglycemic clamps were performed in mice with adult-onset, isolated GH deficiency and in mice with elevated endogenous GH levels due to somatotrope-specific loss of IGF-I and insulin receptors. Our results demonstrate that circulating GH levels are negatively correlated with insulin-mediated glucose uptake in muscle but positively correlated with insulin-mediated suppression of hepatic glucose production. A positive relationship was also observed between GH levels and endpoints of hepatic lipid metabolism known to be regulated by insulin. These results suggest hepatic insulin resistance could represent an early metabolic defect in GH deficiency.
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Affiliation(s)
- Jose Cordoba-Chacon
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Manuel D Gahete
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois; Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, and CIBER de la Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain; and
| | - Owen P McGuinness
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Rhonda D Kineman
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
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22
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Vakili H, Jin Y, Cattini PA. Energy homeostasis targets chromosomal reconfiguration of the human GH1 locus. J Clin Invest 2014; 124:5002-12. [PMID: 25295535 DOI: 10.1172/jci77126] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 08/29/2014] [Indexed: 11/17/2022] Open
Abstract
Levels of pituitary growth hormone (GH), a metabolic homeostatic factor with strong lipolytic activity, are decreased in obese individuals. GH declines prior to the onset of weight gain in response to excess caloric intake and hyperinsulinemia; however, the mechanism by which GH is reduced is not clear. We used transgenic mice expressing the human GH (hGH) gene, GH1, to assess the effect of high caloric intake on expression as well as the local chromosome structure of the intact GH1 locus. Animals exposed to 3 days of high caloric intake exhibited hyperinsulinemia without hyperglycemia and a decrease in both hGH synthesis and secretion, but no difference in endogenous production of murine GH. Efficient GH1 expression requires a long-range intrachromosomal interaction between remote enhancer sequences and the proximal promoter region through "looping" of intervening chromatin. High caloric intake disrupted this interaction and decreased both histone H3/H4 hyperacetylation and RNA polymerase II occupancy at the GH1 promoter. Incorporation of physical activity muted the effects of excess caloric intake on insulin levels, GH1 promoter hyperacetylation, chromosomal architecture, and expression. These results indicate that energy homeostasis alters postnatal hGH synthesis through dynamic changes in the 3-dimensional chromatin structure of the GH1 locus, including structures required for cell type specificity during development.
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23
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Gahete MD, Córdoba-Chacón J, Lantvit DD, Ortega-Salas R, Sanchez-Sanchez R, Pérez-Jiménez F, López-Miranda J, Swanson SM, Castaño JP, Luque RM, Kineman RD. Elevated GH/IGF-I promotes mammary tumors in high-fat, but not low-fat, fed mice. Carcinogenesis 2014; 35:2467-73. [PMID: 25085903 DOI: 10.1093/carcin/bgu161] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Growth hormone (GH) and/or insulin-like growth factor I (IGF-I) are thought to promote breast cancer based on reports showing circulating IGF-I levels correlate, in epidemiological studies, with breast cancer risk. Also, mouse models with developmental GH/IGF-I deficiency/resistance are less susceptible to genetic- or chemical-induced mammary tumorigenesis. However, given the metabolic properties of GH, medical strategies have been considered to raise GH to improve body composition and metabolic function in elderly and obese patients. Since hyperlipidemia, inflammation, insulin resistance and obesity increase breast cancer risk, elevating GH may serve to exacerbate cancer progression. To better understand the role GH/IGF-I plays in tumor formation, this study used unique mouse models to determine if reducing GH/IGF-I in adults protects against 7,12-dimethylbenz[α]anthracene (DMBA)-induced mammary tumor development, and if moderate elevations in endogenous GH/IGF-I alter DMBA-induced tumorigenesis in mice fed a standard-chow diet or in mice with altered metabolic function due to high-fat feeding. We observed that adult-onset isolated GH-deficient mice, which also have reduced IGF-I levels, were less susceptible to DMBA-treatment. Specifically, fewer adult-onset isolated GH-deficient mice developed mammary tumors compared with GH-replete controls. In contrast, chow-fed mice with elevated endogenous GH/IGF-I (HiGH mice) were not more susceptible to DMBA-treatment. However, high-fat-fed, HiGH mice showed reduced tumor latency and increased tumor incidence compared with diet-matched controls. These results further support a role of GH/IGF-I in regulating mammary tumorigenesis but suggest the ultimate consequences of GH/IGF-I on breast tumor development are dependent on the diet and/or metabolic status.
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Affiliation(s)
- Manuel D Gahete
- Research and Development Division, Jesse Brown Veteran Affairs Medical Center, 820 S. Damen Ave, Bldg. 11A, Suite 6215, MP151, Chicago, IL 60612, USA, Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA, Lipid and Atherosclerosis Research Unit, University of Cordoba, Reina Sofia University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain, Department of Cell Biology, Physiology and Immunology, University of Cordoba, Reina Sofia University Hospital, IMIBIC and CIBERObn, Córdoba, Spain
| | - José Córdoba-Chacón
- Research and Development Division, Jesse Brown Veteran Affairs Medical Center, 820 S. Damen Ave, Bldg. 11A, Suite 6215, MP151, Chicago, IL 60612, USA, Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Daniel D Lantvit
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60612, USA and
| | - Rosa Ortega-Salas
- Anatomical Pathology Service, Reina Sofia University Hospital, Cordoba, Spain
| | | | - Francisco Pérez-Jiménez
- Lipid and Atherosclerosis Research Unit, University of Cordoba, Reina Sofia University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain
| | - José López-Miranda
- Lipid and Atherosclerosis Research Unit, University of Cordoba, Reina Sofia University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Cordoba, Spain
| | - Steven M Swanson
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60612, USA and
| | - Justo P Castaño
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Reina Sofia University Hospital, IMIBIC and CIBERObn, Córdoba, Spain
| | - Raúl M Luque
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Reina Sofia University Hospital, IMIBIC and CIBERObn, Córdoba, Spain
| | - Rhonda D Kineman
- Research and Development Division, Jesse Brown Veteran Affairs Medical Center, 820 S. Damen Ave, Bldg. 11A, Suite 6215, MP151, Chicago, IL 60612, USA, Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA,
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Ma K, Malhotra P, Soni V, Hedroug O, Annaba F, Dudeja A, Shen L, Turner JR, Khramtsova EA, Saksena S, Dudeja PK, Gill RK, Alrefai WA. Overactivation of intestinal SREBP2 in mice increases serum cholesterol. PLoS One 2014; 9:e84221. [PMID: 24465397 PMCID: PMC3896331 DOI: 10.1371/journal.pone.0084221] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 11/13/2013] [Indexed: 12/21/2022] Open
Abstract
Sterol Response Element Binding Protein 2 (SREBP2) transcription factor is a master regulator of cholesterol homeostasis. Treatment with statins, inhibitors of cholesterol synthesis, activates intestinal SREBP2, which may hinder their cholesterol-lowering effects. Overactivation of SREBP2 in mouse liver was shown to have no effect on plasma cholesterol. However, the influence of activating intestinal SREBP2 on plasma cholesterol is not known. We have generated a novel transgenic mouse model with intestine specific overexpression of active SREBP2 (ISR2) driven by villin promoter. ISR2 mice showed overexpression of active SREBP2 specifically in the intestine. Microarray analysis of jejunal RNA from ISR2 mice showed a significant increase in genes involved in fatty acid and cholesterol synthesis. Cholesterol and triglyceride (TG) in jejunum and liver (mg/g protein) were significantly increased in ISR2 vs wild type mice. Serum Cholesterol was significantly increased in VLDL and LDL fractions whereas the level of serum triglycerides was decreased in ISR2 vs wild type mice. In conclusion, activation of intestinal SREBP2 alone seems to be sufficient to increase plasma cholesterol, highlighting the essential role of intestine in maintaining cholesterol homeostasis in the body.
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Affiliation(s)
- Ke Ma
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Pooja Malhotra
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Vinay Soni
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Omar Hedroug
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Fadi Annaba
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Amish Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Le Shen
- Department of Surgery, University of Chicago, Chicago, Illinois, United States of America
| | - Jerrold R. Turner
- Department of Pathology, University of Chicago, Chicago, Illinois, United States of America
| | | | - Seema Saksena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Pradeep K. Dudeja
- Research and Development, Jesse Brown VA Medical Center, Chicago, Illinois, United States of America
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Ravinder K. Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Waddah A. Alrefai
- Research and Development, Jesse Brown VA Medical Center, Chicago, Illinois, United States of America
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
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25
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Gahete MD, Córdoba-Chacón J, Lin Q, Brüning JC, Kahn CR, Castaño JP, Christian H, Luque RM, Kineman RD. Insulin and IGF-I inhibit GH synthesis and release in vitro and in vivo by separate mechanisms. Endocrinology 2013; 154:2410-20. [PMID: 23671263 PMCID: PMC3689283 DOI: 10.1210/en.2013-1261] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
IGF-I is considered a primary inhibitor of GH secretion. Insulin may also play an important role in regulating GH levels because insulin, like IGF-I, can suppress GH synthesis and release in primary pituitary cell cultures and insulin is negatively correlated with GH levels in vivo. However, understanding the relative contribution insulin and IGF-I exert on controlling GH secretion has been hampered by the fact that circulating insulin and IGF-I are regulated in parallel and insulin (INSR) and IGF-I (IGFIR) receptors are structurally/functionally related and ubiquitously expressed. To evaluate the separate roles of insulin and IGF-I in directly regulating GH secretion, we used the Cre/loxP system to knock down the INSR and IGFIR in primary mouse pituitary cell cultures and found insulin-mediated suppression of GH is independent of the IGFIR. In addition, pharmacological blockade of intracellular signals in both mouse and baboon cultures revealed insulin requires different pathways from IGF-I to exert a maximal inhibitory effect on GH expression/release. In vivo, somatotrope-specific knockout of INSR (SIRKO) or IGFIR (SIGFRKO) increased GH levels. However, comparison of the pattern of GH release, GH expression, somatotrope morphometry, and pituitary explant sensitivity to acute GHRH challenge in lean SIRKO and SIGFRKO mice strongly suggests the primary role of insulin in vivo is to suppress GH release, whereas IGF-I serves to regulate GH synthesis. Finally, SIRKO and/or SIGFRKO could not prevent high-fat, diet-induced suppression of pituitary GH expression, indicating other factors/tissues are involved in the decline of GH observed with weight gain.
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Affiliation(s)
- Manuel D Gahete
- Research and Development Division, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
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26
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Berryman DE, Glad CAM, List EO, Johannsson G. The GH/IGF-1 axis in obesity: pathophysiology and therapeutic considerations. Nat Rev Endocrinol 2013; 9:346-56. [PMID: 23568441 DOI: 10.1038/nrendo.2013.64] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Obesity has become one of the most common medical problems in developed countries, and this disorder is associated with high incidences of hypertension, dyslipidaemia, cardiovascular disease, type 2 diabetes mellitus and specific cancers. Growth hormone (GH) stimulates the production of insulin-like growth factor 1 in most tissues, and together GH and insulin-like growth factor 1 exert powerful collective actions on fat, protein and glucose metabolism. Clinical trials assessing the effects of GH treatment in patients with obesity have shown consistent reductions in total adipose tissue mass, in particular abdominal and visceral adipose tissue depots. Moreover, studies in patients with abdominal obesity demonstrate a marked effect of GH therapy on body composition and on lipid and glucose homeostasis. Therefore, administration of recombinant human GH or activation of endogenous GH production has great potential to influence the onset and metabolic consequences of obesity. However, the clinical use of GH is not without controversy, given conflicting results regarding its effects on glucose metabolism. This Review provides an introduction to the role of GH in obesity and summarizes clinical and preclinical data that describe how GH can influence the obese state.
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Affiliation(s)
- Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges, Athens, OH 45701, USA
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Lubbers ER, List EO, Jara A, Sackman-Sala L, Cordoba-Chacon J, Gahete MD, Kineman RD, Boparai R, Bartke A, Kopchick JJ, Berryman DE. Adiponectin in mice with altered GH action: links to insulin sensitivity and longevity? J Endocrinol 2013; 216:363-74. [PMID: 23261955 PMCID: PMC3756886 DOI: 10.1530/joe-12-0505] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Adiponectin is positively correlated with longevity and negatively correlated with many obesity-related diseases. While there are several circulating forms of adiponectin, the high-molecular-weight (HMW) version has been suggested to have the predominant bioactivity. Adiponectin gene expression and cognate serum protein levels are of particular interest in mice with altered GH signaling as these mice exhibit extremes in obesity that are positively associated with insulin sensitivity and lifespan as opposed to the typical negative association of these factors. While a few studies have reported total adiponectin levels in young adult mice with altered GH signaling, much remains unresolved, including changes in adiponectin levels with advancing age, proportion of total adiponectin in the HMW form, adipose depot of origin, and differential effects of GH vs IGF1. Therefore, the purpose of this study was to address these issues using assorted mouse lines with altered GH signaling. Our results show that adiponectin is generally negatively associated with GH activity, regardless of age. Further, the amount of HMW adiponectin is consistently linked with the level of total adiponectin and not necessarily with previously reported lifespan or insulin sensitivity of these mice. Interestingly, circulating adiponectin levels correlated strongly with inguinal fat mass, implying that the effects of GH on adiponectin are depot specific. Interestingly, rbGH, but not IGF1, decreased circulating total and HMW adiponectin levels. Taken together, these results fill important gaps in the literature related to GH and adiponectin and question the frequently reported associations of total and HMW adiponectin with insulin sensitivity and longevity.
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Affiliation(s)
- Ellen R. Lubbers
- Edison Biotechnology Institute, Ohio University, Athens, OH 45701
| | - Edward O. List
- Edison Biotechnology Institute, Ohio University, Athens, OH 45701
| | - Adam Jara
- Edison Biotechnology Institute, Ohio University, Athens, OH 45701
- Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH
| | | | | | - Manuel D. Gahete
- Jesse Brown VA Medical Center, Research and Development, Chicago IL 60612
| | - Rhonda D. Kineman
- Jesse Brown VA Medical Center, Research and Development, Chicago IL 60612
| | - Ravneet Boparai
- Southern Illinois University School of Medicine, Springfield, IL 62794
| | - Andrzej Bartke
- Southern Illinois University School of Medicine, Springfield, IL 62794
| | - John J. Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH 45701
- Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH
| | - Darlene E. Berryman
- Edison Biotechnology Institute, Ohio University, Athens, OH 45701
- Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH
- School of Applied Health Sciences and Wellness, College of Health Sciences and Professions, Ohio University, Athens, OH 45701
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Gahete MD, Córdoba-Chacón J, Luque RM, Kineman RD. The rise in growth hormone during starvation does not serve to maintain glucose levels or lean mass but is required for appropriate adipose tissue response in female mice. Endocrinology 2013; 154:263-9. [PMID: 23150490 PMCID: PMC3529368 DOI: 10.1210/en.2012-1849] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In mice, GH levels rise in response to short-term fasting or starvation (food restriction to 40% of ad libitum intake), similar to that which occurs in humans in response to fasting or anorexia. Recent studies using acyl-ghrelin knockout mice have suggested that the rise in GH during food restriction is essential to support glucose levels. To directly test this hypothesis, adult-onset isolated GH deficient (AOiGHD) mice and their GH-replete littermate controls were provided 40% of ad libitum food intake for 11 d. As previously shown, food restriction increased GH levels in controls, and this response was not observed in AOiGHD mice. In both controls and AOiGHD, food restriction resulted in an initial decline in glucose, which stabilized to 82-85% of ad libitum-fed values by d 2. In addition, loss of lean mass in response to food restriction was not altered by GH status. However, the loss of fat mass and the associated rise in circulating free fatty acids and ketones was blunted in starved AOiGHD mice compared with controls. Taken together, these results suggest a rise of GH during starvation is not required to support glucose levels and muscle mass but may be important in supporting fat mobilization.
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Affiliation(s)
- Manuel D Gahete
- Research and Development Division, University of Illinois at Chicago, Chicago, IL 60612, USA
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Cordoba-Chacon J, Gahete MD, Pozo-Salas AI, Moreno-Herrera A, Castaño JP, Kineman RD, Luque RM. Peripubertal-onset but not adult-onset obesity increases IGF-I and drives development of lean mass, which may lessen the metabolic impairment in adult obesity. Am J Physiol Endocrinol Metab 2012; 303:E1151-7. [PMID: 22932784 PMCID: PMC3774069 DOI: 10.1152/ajpendo.00340.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It has been suggested that adult metabolic dysfunction may be more severe in individuals who become obese as children compared with those who become obese later in life. To determine whether adult metabolic function differs if diet-induced weight gain occurs during the peripubertal age vs. if excess weight gain occurs after puberty, male C57Bl/6J mice were fed a low-fat (LF; 10% kcal from fat) or high-fat (HF; 60% kcal from fat) diet starting during the peripubertal period (pHF; 4 wk of age) or as adults (aHF; 12 wk of age). Both pHF and aHF mice were hyperinsulinemic and hyperglycemic, and both showed impaired glucose tolerance and insulin resistance compared with their LF-fed controls. However, despite a longer time on diet, pHF mice were relatively more insulin sensitive than aHF mice, which was associated with higher lean mass and circulating IGF-I levels. In addition, HF feeding had an overall stimulatory effect on circulating corticosterone levels; however, this rise was associated only with elevated plasma ACTH in the aHF mice. Despite the belief that adult metabolic dysfunction may be more severe in individuals who become obese as children, data generated using a diet-induced obese mouse model suggest that adult metabolic dysfunction associated with peripubertal onset of obesity is not worse than that associated with adult-onset obesity.
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Affiliation(s)
- Jose Cordoba-Chacon
- Department of Cell Biology, Physiology, and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, University of Cordoba Centro de Investigacion Biomedica en Red Fisiopatologia de Obesidad y Nutricion, Córdoba, Spain
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