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Biglari N, Gaziano I, Schumacher J, Radermacher J, Paeger L, Klemm P, Chen W, Corneliussen S, Wunderlich CM, Sue M, Vollmar S, Klöckener T, Sotelo-Hitschfeld T, Abbasloo A, Edenhofer F, Reimann F, Gribble FM, Fenselau H, Kloppenburg P, Wunderlich FT, Brüning JC. Functionally distinct POMC-expressing neuron subpopulations in hypothalamus revealed by intersectional targeting. Nat Neurosci 2021; 24:913-929. [PMID: 34002087 PMCID: PMC8249241 DOI: 10.1038/s41593-021-00854-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/31/2021] [Indexed: 02/03/2023]
Abstract
Pro-opiomelanocortin (POMC)-expressing neurons in the arcuate nucleus of the hypothalamus represent key regulators of metabolic homeostasis. Electrophysiological and single-cell sequencing experiments have revealed a remarkable degree of heterogeneity of these neurons. However, the exact molecular basis and functional consequences of this heterogeneity have not yet been addressed. Here, we have developed new mouse models in which intersectional Cre/Dre-dependent recombination allowed for successful labeling, translational profiling and functional characterization of distinct POMC neurons expressing the leptin receptor (Lepr) and glucagon like peptide 1 receptor (Glp1r). Our experiments reveal that POMCLepr+ and POMCGlp1r+ neurons represent largely nonoverlapping subpopulations with distinct basic electrophysiological properties. They exhibit a specific anatomical distribution within the arcuate nucleus and differentially express receptors for energy-state communicating hormones and neurotransmitters. Finally, we identify a differential ability of these subpopulations to suppress feeding. Collectively, we reveal a notably distinct functional microarchitecture of critical metabolism-regulatory neurons.
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Affiliation(s)
- Nasim Biglari
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Isabella Gaziano
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Jonas Schumacher
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Jan Radermacher
- grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
| | - Lars Paeger
- grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
| | - Paul Klemm
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Weiyi Chen
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Svenja Corneliussen
- grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
| | - Claudia M. Wunderlich
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Michael Sue
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany
| | - Stefan Vollmar
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany
| | - Tim Klöckener
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Tamara Sotelo-Hitschfeld
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Amin Abbasloo
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany
| | - Frank Edenhofer
- grid.5771.40000 0001 2151 8122Leopold-Franzens-Universität Innsbruck, Institute for Molecular Biology, Innsbruck, Austria
| | - Frank Reimann
- grid.120073.70000 0004 0622 5016Cambridge Institute for Medical Research and Medical Research Council Metabolic Diseases Unit, Addenbrooke’s Hospital, Cambridge, UK
| | - Fiona M. Gribble
- grid.120073.70000 0004 0622 5016Cambridge Institute for Medical Research and Medical Research Council Metabolic Diseases Unit, Addenbrooke’s Hospital, Cambridge, UK
| | - Henning Fenselau
- grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Research Group Synaptic Transmission in Energy Homeostasis, Cologne, Germany
| | - Peter Kloppenburg
- grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
| | - Frank T. Wunderlich
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Jens C. Brüning
- grid.418034.a0000 0004 4911 0702Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Cologne, Germany ,grid.411097.a0000 0000 8852 305XPoliclinic for Endocrinology, Diabetes and Preventive Medicine (PEDP), University Hospital Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany ,National Center for Diabetes Research (DZD), Ingolstädter Landstrasse 1, Neuherberg, Germany
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52
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Kalsbeek MJT, Yi CX. The infundibular peptidergic neurons and glia cells in overeating, obesity, and diabetes. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:315-325. [PMID: 34225937 DOI: 10.1016/b978-0-12-820107-7.00019-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Dysfunctional regulation of energy homeostasis results in increased bodyweight and obesity, eventually leading to type 2 diabetes mellitus. The infundibular nucleus (IFN) of the hypothalamus is the main regulator of energy homeostasis. The peptidergic neurons and glia cells of the IFN receive metabolic cues concerning energy state of the body from the circulation. The IFN can monitor hormones like insulin and leptin and nutrients like glucose and fatty acids. All these metabolic cues are integrated into an output signal regulating energy homeostasis through the release of neuropeptides. These neuropeptides are released in several inter- and extrahypothalamic brain regions involved in regulation of energy homeostasis. This review will give an overview of the peripheral signals involved in the regulation of energy homeostasis, the peptidergic neurons and glial cells of the IFN, and will highlight the main intra-hypothalamic projection sites of the IFN.
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Affiliation(s)
- Martin J T Kalsbeek
- Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology Metabolism, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
| | - Chun-Xia Yi
- Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology Metabolism, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands; Department of Endocrinology and Metabolism, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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53
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Unraveling the Role of Leptin in Liver Function and Its Relationship with Liver Diseases. Int J Mol Sci 2020; 21:ijms21249368. [PMID: 33316927 PMCID: PMC7764544 DOI: 10.3390/ijms21249368] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/19/2020] [Accepted: 12/04/2020] [Indexed: 02/06/2023] Open
Abstract
Since its discovery twenty-five years ago, the fat-derived hormone leptin has provided a revolutionary framework for studying the physiological role of adipose tissue as an endocrine organ. Leptin exerts pleiotropic effects on many metabolic pathways and is tightly connected with the liver, the major player in systemic metabolism. As a consequence, understanding the metabolic and hormonal interplay between the liver and adipose tissue could provide us with new therapeutic targets for some chronic liver diseases, an increasing problem worldwide. In this review, we assess relevant literature regarding the main metabolic effects of leptin on the liver, by direct regulation or through the central nervous system (CNS). We draw special attention to the contribution of leptin to the non-alcoholic fatty liver disease (NAFLD) pathogenesis and its progression to more advanced stages of the disease as non-alcoholic steatohepatitis (NASH). Likewise, we describe the contribution of leptin to the liver regeneration process after partial hepatectomy, the mainstay of treatment for certain hepatic malignant tumors.
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54
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Haigh JL, New LE, Filippi BM. Mitochondrial Dynamics in the Brain Are Associated With Feeding, Glucose Homeostasis, and Whole-Body Metabolism. Front Endocrinol (Lausanne) 2020; 11:580879. [PMID: 33240218 PMCID: PMC7680879 DOI: 10.3389/fendo.2020.580879] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/05/2020] [Indexed: 12/13/2022] Open
Abstract
The brain is responsible for maintaining whole-body energy homeostasis by changing energy input and availability. The hypothalamus and dorsal vagal complex (DVC) are the primary sites of metabolic control, able to sense both hormones and nutrients and adapt metabolism accordingly. The mitochondria respond to the level of nutrient availability by fusion or fission to maintain energy homeostasis; however, these processes can be disrupted by metabolic diseases including obesity and type II diabetes (T2D). Mitochondrial dynamics are crucial in the development and maintenance of obesity and T2D, playing a role in the control of glucose homeostasis and whole-body metabolism across neurons and glia in the hypothalamus and DVC.
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Affiliation(s)
| | | | - Beatrice M. Filippi
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
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55
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Tran H, Poinsot P, Guillaume S, Delaunay D, Bernetiere M, Bégin C, Fourneret P, Peretti N, Iceta S. FOOD ADDICTION AS A PROXY FOR ANOREXIA NERVOSA SEVERITY: NEW DATA BASED ON THE YALE FOOD ADDICTION SCALE 2.0. Psychiatry Res 2020; 293:113472. [PMID: 33007684 DOI: 10.1016/j.psychres.2020.113472] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 09/19/2020] [Indexed: 12/12/2022]
Abstract
The contribution of an addictive process to anorexia nervosa (AN) is an area of growing interest. Yet, little is known about how the food addiction concept (FA) may be of interest in understanding AN. This study investigates prevalence of FA diagnostic and its association with markers of severity in individuals with AN. We conducted a retrospective study in a sample of 73 patients with AN. We assessed FA with the Yale Food Addiction Scale 2.0, depressive and anxiety disorders, impulsivity (Beck Depression Inventory, STAI, BIS-11) and eating behavior (BITE, EDE-Q). Prevalence of FA in our sample was 47%. FA was significantly associated and positively correlated with the binge-eating/purging subtype of AN, higher levels of depression, anxiety and greater eating psychopathology. FA was not associated with level of impulsivity nor leptin and IGF-1 blood levels. The relationship between FA severity and AN severity was mediated by the severity of binge eating behaviors. Our results suggest that the presence of FA may represent a more severe variant of AN. Longitudinal studies are needed to better understand the etiologic process between FA and AN.
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Affiliation(s)
- Helene Tran
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France
| | - Pierre Poinsot
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France; Univ Lyon, CarMeN laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, F-69310 Pierre-Benite, France; Departement of Pediatric Nutrition, Hôpital Femme Mère Enfant, Univ Lyon, Hospice Civil de Lyon, Bron, F-69002, France
| | - Sebastien Guillaume
- Department of Emergency Psychiatry and Post-Acute Care, Lapeyronie Hospital CHRU Montpellier, Montpellier, F-34295, France; INSERM U1061, Montpellier, France; Université de Montpellier, Montpellier, F-34093 France
| | - Dominique Delaunay
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France
| | - Marion Bernetiere
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France
| | - Catherine Bégin
- Centre Nutrition, santé et société (NUTRISS), Institute of Nutrition and Functional Foods, Université Laval, Québec, QC G1V 0A6, Canada; School of Psychology, Laval University, QC G1V 0A6, Canada.; Quebec Heart and Lung Institute (IUCPQ), Québec, QC G1V 4G5, Canada. School of Nutrition, Laval University, Québec, QC, G1V 0A6, Canada
| | - Pierre Fourneret
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France
| | - Noel Peretti
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France; Univ Lyon, CarMeN laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, F-69310 Pierre-Benite, France; Departement of Pediatric Nutrition, Hôpital Femme Mère Enfant, Univ Lyon, Hospice Civil de Lyon, Bron, F-69002, France
| | - Sylvain Iceta
- Referral Center for Eating Disorder, Hospices Civils de Lyon, F-69677 Bron, France; Univ Lyon, CarMeN laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, F-69310 Pierre-Benite, France; Quebec Heart and Lung Institute (IUCPQ), Québec, QC G1V 4G5, Canada. School of Nutrition, Laval University, Québec, QC, G1V 0A6, Canada.
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56
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Yu H, Thompson Z, Kiran S, Jones GL, Mundada L, Rubinstein M, Low MJ. Expression of a hypomorphic Pomc allele alters leptin dynamics during late pregnancy. J Endocrinol 2020; 245:115-127. [PMID: 32027603 DOI: 10.1530/joe-19-0576] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 02/06/2020] [Indexed: 12/11/2022]
Abstract
Proopiomelanocortin (POMC) neurons in the hypothalamic arcuate nucleus (ARC) are essential for normal energy homeostasis. Maximal ARC Pomc transcription is dependent on neuronal Pomc enhancer 1 (nPE1), located 12 kb upstream from the promoter. Selective deletion of nPE1 in mice decreases ARC Pomc expression by 70%, sufficient to induce mild obesity. Because nPE1 is located exclusively in the genomes of placental mammals, we questioned whether its hypomorphic mutation would also alter placental Pomc expression and the metabolic adaptations associated with pregnancy and lactation. We assessed placental development, pup growth, circulating leptin and expression of Pomc, Agrp and alternatively spliced leptin receptor (LepR) isoforms in the ARC and placenta of Pomc∆1/∆1 and Pomc+/+ dams. Despite indistinguishable body weights, lean mass, food intake, placental histology and Pomc expression and overall pregnancy outcomes between the genotypes, Pomc ∆1/∆1 females had increased pre-pregnancy fat mass that paradoxically decreased to control levels by parturition. However, Pomc∆1/∆1 dams had exaggerated increases in circulating leptin, up to twice of that of the typically elevated levels in Pomc+/+ mice at the end of pregnancy, despite their equivalent fat mass. Pomc∆1/∆1dams also had increased placental expression of soluble leptin receptor (LepRe), although the protein levels of LEPRE in circulation were the same as Pomc+/+ controls. Together, these data suggest that the hypomorphic Pomc∆1/∆1 allele is responsible for the perinatal super hyperleptinemia of Pomc∆1/∆1 dams, possibly due to upregulated leptin secretion from individual adipocytes.
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Affiliation(s)
- Hui Yu
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Zoe Thompson
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Sylee Kiran
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,School of Literature, Science, and Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Graham L Jones
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Lakshmi Mundada
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | -
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Marcelo Rubinstein
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Instituto de Investigaciones en Ingeniería Genética y Biología Molecular Consejo Nacional de Investigaciones Científicas y Técnicas and Facultad de Ciencias Exactas y Naturales, Universidad de Buenos, Buenos Aires, Argentina
| | - Malcolm J Low
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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57
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Rau AR, King CM, Hentges ST. Disruption of GABA or glutamate release from POMC neurons in the adult mouse does not affect metabolic end points. Am J Physiol Regul Integr Comp Physiol 2020; 319:R592-R601. [PMID: 32936679 DOI: 10.1152/ajpregu.00180.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Proopiomelanocortin (POMC) neurons contribute to the regulation of many physiological processes; the majority of which have been attributed to the release of peptides produced from the POMC prohormone such as α-MSH, which plays key roles in food intake and metabolism. However, it is now clear that POMC neurons also release amino acid transmitters that likely contribute to the overall function of POMC cells. Recent work indicates that constitutive deletion of these transmitters can affect metabolic phenotypes, but also that the expression of GABAergic or glutamatergic markers changes throughout development. The goal of the present study was to determine whether the release of glutamate or GABA from POMC neurons in the adult mouse contributes notably to energy balance regulation. Disturbed release of glutamate or GABA specifically from POMC neurons in adult mice was achieved using a tamoxifen-inducible Cre construct (Pomc-CreERT2) expressed in mice also carrying floxed versions of Slc17a6 (vGlut2) or Gad1 and Gad2, encoding the vesicular glutamate transporter type 2 and GAD67 and GAD65 proteins, respectively. All mice in the experiments received tamoxifen injections, but control mice lacked the tamoxifen-inducible Cre sequence. Body weight was unchanged in Gad1- and Gad2- or vGlut2-deleted female and male mice. Additionally, no significant differences in glucose tolerance or refeeding after an overnight fast were observed. These data collectively suggest that the release of GABA or glutamate from POMC neurons in adult mice does not significantly contribute to the metabolic parameters tested here. In light of prior work, the data also suggest that amino acid transmitter release from POMC cells may contribute to separate functions in the adult versus the developing mouse.
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Affiliation(s)
- Andrew R Rau
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Connie M King
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Shane T Hentges
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado
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58
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Effects of metabolic state on the regulation of melanocortin circuits. Physiol Behav 2020; 224:113039. [PMID: 32610101 PMCID: PMC7387173 DOI: 10.1016/j.physbeh.2020.113039] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 06/01/2020] [Accepted: 06/26/2020] [Indexed: 12/14/2022]
Abstract
Dysfunction in neurophysiological systems that regulate food intake and metabolism are at least partly responsible for obesity and related comorbidities. An important component of this process is the hypothalamic melanocortin system, where an imbalance can result in severe obesity and deficits in glucose metabolism. Exercise offers many health benefits related to cardiovascular improvements, hunger control, and blood glucose homeostasis. However, the molecular mechanism underlying the exercise-induced improvements to the melanocortin system remain undefined. Here, we review the role of the melanocortin system to sense hormonal, nutrient, and neuronal signals of energy status. This information is then relayed onto secondary neurons in order to regulate physiological parameters, which promote proper energy and glucose balance. We also provide an overview on the effects of physical exercise to induce biophysical changes in the melanocortin circuit which may regulate food intake, glucose metabolism and improve overall metabolic health.
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59
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Deng G, Morselli LL, Wagner VA, Balapattabi K, Sapouckey SA, Knudtson KL, Rahmouni K, Cui H, Sigmund CD, Kwitek AE, Grobe JL. Single-Nucleus RNA Sequencing of the Hypothalamic Arcuate Nucleus of C57BL/6J Mice After Prolonged Diet-Induced Obesity. Hypertension 2020; 76:589-597. [PMID: 32507042 DOI: 10.1161/hypertensionaha.120.15137] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Prolonged obesity is associated with blunted feeding and thermogenic autonomic responses to leptin, but cardiovascular responses to leptin are maintained. This state of selective leptin resistance is, therefore, proposed to contribute to the pathogenesis and maintenance of obesity-associated hypertension. Cells of the arcuate nucleus of the hypothalamus detect leptin, and although the cellular and molecular mechanisms remain unclear, altered arcuate nucleus biology is hypothesized to contribute to selective leptin resistance. Male C57BL/6J mice were fed a high-fat diet (HFD) or chow from 8 to 18 weeks of age, as this paradigm models selective leptin resistance. Nuclei were then isolated from arcuate nucleus for single-nucleus RNA sequencing. HFD caused expected gains in adiposity and circulating leptin. Twenty-three unique cell-type clusters were identified, and Ingenuity Pathway Analysis was used to explore changes in gene expression patterns due to chronic HFD within each cluster. Notably, gene expression signatures related to leptin signaling exhibited suppression predominantly in neurons identified as the Agouti-related peptide (Agrp) subtype. Ingenuity Pathway Analysis results were also consistent with alterations in CREB (cAMP response element-binding protein) signaling in Agrp neurons after HFD, and reduced phosphorylated CREB was confirmed in arcuate nucleus after prolonged HFD by capillary electrophoresis-based Western blotting. These findings support the concept that prolonged HFD-induced obesity is associated with selective changes in Agrp neuron biology, possibly secondary to altered CREB signaling.
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Affiliation(s)
- Guorui Deng
- From the Department of Neuroscience and Pharmacology (G.D., S.A.S., K.R., H.C.), University of Iowa
| | - Lisa L Morselli
- Division of Endocrinology, Department of Internal Medicine (L.L.M.), University of Iowa
| | - Valerie A Wagner
- Department of Physiology (V.A.W., K.B., C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee
| | - Kirthikaa Balapattabi
- Department of Physiology (V.A.W., K.B., C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee
| | - Sarah A Sapouckey
- From the Department of Neuroscience and Pharmacology (G.D., S.A.S., K.R., H.C.), University of Iowa
| | | | - Kamal Rahmouni
- From the Department of Neuroscience and Pharmacology (G.D., S.A.S., K.R., H.C.), University of Iowa.,Obesity Research and Education Initiative (K.R., H.C.), University of Iowa.,Iowa Neuroscience Institute (K.R., H.C.), University of Iowa
| | - Huxing Cui
- From the Department of Neuroscience and Pharmacology (G.D., S.A.S., K.R., H.C.), University of Iowa.,Obesity Research and Education Initiative (K.R., H.C.), University of Iowa.,Iowa Neuroscience Institute (K.R., H.C.), University of Iowa
| | - Curt D Sigmund
- Department of Physiology (V.A.W., K.B., C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee.,Cardiovascular Center (C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee
| | - Anne E Kwitek
- Department of Physiology (V.A.W., K.B., C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee.,Cardiovascular Center (C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee.,Department of Medicine (A.E.K.), Medical College of Wisconsin, Milwaukee
| | - Justin L Grobe
- Department of Physiology (V.A.W., K.B., C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee.,Cardiovascular Center (C.D.S., A.E.K., J.L.G.), Medical College of Wisconsin, Milwaukee.,Department of Biomedical Engineering (J.L.G.), Medical College of Wisconsin, Milwaukee.,Comprehensive Rodent Metabolic Phenotyping Core (J.L.G.), Medical College of Wisconsin, Milwaukee
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60
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Münzberg H, Singh P, Heymsfield SB, Yu S, Morrison CD. Recent advances in understanding the role of leptin in energy homeostasis. F1000Res 2020; 9. [PMID: 32518627 PMCID: PMC7255681 DOI: 10.12688/f1000research.24260.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/19/2020] [Indexed: 01/04/2023] Open
Abstract
The hormone leptin plays a critical role in energy homeostasis, although our overall understanding of acutely changing leptin levels still needs improvement. Several developments allow a fresh look at recent and early data on leptin action. This review highlights select recent publications that are relevant for understanding the role played by dynamic changes in circulating leptin levels. We further discuss the relevance for our current understanding of leptin signaling in central neuronal feeding and energy expenditure circuits and highlight cohesive and discrepant findings that need to be addressed in future studies to understand how leptin couples with physiological adaptations of food intake and energy expenditure.
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Affiliation(s)
- Heike Münzberg
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Prachi Singh
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Steven B Heymsfield
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Sangho Yu
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Christopher D Morrison
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
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Abstract
The successful use of leptin for the treatment of individuals with lipodystrophy and leptin deficiency is well established. However, pharmacological approaches of leptin therapy for the treatment of diet-induced obesity have been ineffective. There is ample room for a better understanding of the much famed "leptin resistance" phenomenon. Our recent data in this area prompt us to call for a conceptual shift. This shift entails a model in which a reduction of bioactive leptin levels in the context of obesity triggers a high degree of leptin sensitization and improved leptin action, both centrally and peripherally. Put another way, hyperleptinemia per se causes leptin resistance and associated metabolic disorders. In this perspective, we briefly discuss the underlying conceptual steps that led us to explore partial leptin reduction as a viable therapeutic avenue. We hope this discussion will contribute to potential future applications of partial leptin reduction therapy for the treatment of obesity and type 2 diabetes.
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Affiliation(s)
- Shangang Zhao
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Christine M Kusminski
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Joel K Elmquist
- Division of Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
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Chen X, Wyler SC, Li L, Arnold AG, Wan R, Jia L, Landy MA, Lai HC, Xu P, Liu C. Comparative Transcriptomic Analyses of Developing Melanocortin Neurons Reveal New Regulators for the Anorexigenic Neuron Identity. J Neurosci 2020; 40:3165-3177. [PMID: 32213554 PMCID: PMC7159888 DOI: 10.1523/jneurosci.0155-20.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/28/2020] [Accepted: 03/09/2020] [Indexed: 02/07/2023] Open
Abstract
Despite their opposing actions on food intake, POMC and NPY/AgRP neurons in the arcuate nucleus of the hypothalamus (ARH) are derived from the same progenitors that give rise to ARH neurons. However, the mechanism whereby common neuronal precursors subsequently adopt either the anorexigenic (POMC) or the orexigenic (NPY/AgRP) identity remains elusive. We hypothesize that POMC and NPY/AgRP cell fates are specified and maintained by distinct intrinsic factors. In search of them, we profiled the transcriptomes of developing POMC and NPY/AgRP neurons in mice. Moreover, cell-type-specific transcriptomic analyses revealed transcription regulators that are selectively enriched in either population, but whose developmental functions are unknown in these neurons. Among them, we found the expression of the PR domain-containing factor 12 (Prdm12) was enriched in POMC neurons but absent in NPY/AgRP neurons. To study the role of Prdm12 in vivo, we developed and characterized a floxed Prdm12 allele. Selective ablation of Prdm12 in embryonic POMC neurons led to significantly reduced Pomc expression as well as early-onset obesity in mice of either sex that recapitulates symptoms of human POMC deficiency. Interestingly, however, specific deletion of Prdm12 in adult POMC neurons showed that it is no longer required for Pomc expression or energy balance. Collectively, these findings establish a critical role for Prdm12 in the anorexigenic neuron identity and suggest that it acts developmentally to program body weight homeostasis. Finally, the combination of cell-type-specific genomic and genetic analyses provides a means to dissect cellular and functional diversity in the hypothalamus whose neurodevelopment remains poorly studied.SIGNIFICANCE STATEMENT POMC and NPY/AgRP neurons are derived from the same hypothalamic progenitors but have opposing effects on food intake. We profiled the transcriptomes of genetically labeled POMC and NPY/AgRP neurons in the developing mouse hypothalamus to decipher the transcriptional codes behind the versus orexigenic neuron identity. Our analyses revealed 29 transcription regulators that are selectively enriched in one of the two populations. We generated new mouse genetic models to selective ablate one of POMC-neuron enriched transcription factors Prdm12 in developing and adult POMC neurons. Our studies establish a previously unrecognized role for Prdm12 in the anorexigenic neuron identity and suggest that it acts developmentally to program body weight homeostasis.
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Affiliation(s)
- Xiameng Chen
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Steven C Wyler
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Li Li
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Amanda G Arnold
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Rong Wan
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Lin Jia
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
| | - Mark A Landy
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Helen C Lai
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Pin Xu
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Chen Liu
- Department of Internal Medicine, Hypothalamic Research Center, Dallas, Texas 75390
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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Yu H, Chhabra KH, Thompson Z, Jones GL, Kiran S, Shangguan G, Low MJ. Hypothalamic POMC deficiency increases circulating adiponectin despite obesity. Mol Metab 2020; 35:100957. [PMID: 32244188 PMCID: PMC7082555 DOI: 10.1016/j.molmet.2020.01.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/22/2020] [Accepted: 01/31/2020] [Indexed: 02/06/2023] Open
Abstract
Objective The steep rise in the prevalence of obesity and its related metabolic syndrome have become a major worldwide health concerns. Melanocortin peptides from hypothalamic arcuate nucleus (Arc) POMC neurons induce satiety to limit food intake. Consequently, Arc Pomc-deficient mice (ArcPomc−/−) exhibit hyperphagia and obesity. Previous studies demonstrated that the circulating levels of adiponectin, a protein abundantly produced and secreted by fat cells, negatively correlate with obesity in both rodents and humans. However, we found that ArcPomc−/− mice have increased circulating adiponectin levels despite obesity. Therefore, we investigated the physiological function and underlying mechanisms of hypothalamic POMC in regulating systemic adiponectin levels. Methods Circulating adiponectin was measured in obese ArcPomc−/− mice at ages 4–52 weeks. To determine whether increased adiponectin was a direct result of ArcPomc deficiency or a secondary effect of obesity, we examined plasma adiponectin levels in calorie-restricted mice with or without a history of obesity and in ArcPomc−/− mice before and after genetic restoration of Pomc expression in the hypothalamus. To delineate the mechanisms causing increased adiponectin in ArcPomc−/− mice, we determined sympathetic outflow to adipose tissue by assessing epinephrine, norepinephrine, and tyrosine hydroxylase protein levels and measured the circulating adiponectin in the mice after acute norepinephrine or propranolol treatments. In addition, adiponectin mRNA and protein levels were measured in discrete adipose tissue depots to ascertain which fat depots contributed the most to the high level of adiponectin in the ArcPomc−/− mice. Finally, we generated compound Adiopoq−/−:ArcPomc−/− mice and compared their growth, body composition, and glucose homeostasis to the individual knockout mouse strains and their wild-type controls. Results Obese ArcPomc−/− female mice had unexpectedly increased plasma adiponectin compared to wild-type siblings at all ages greater than 8 weeks. Despite chronic calorie restriction to achieve normal body weights, higher adiponectin levels persisted in the ArcPomc−/− female mice. Genetic restoration of Pomc expression in the Arc or acute treatment of the ArcPomc−/− female mice with melanotan II reduced adiponectin levels to control littermate values. The ArcPomc−/− mice had defective thermogenesis and decreased epinephrine, norepinephrine, and tyrosine hydroxylase protein levels in their fat pads, indicating reduced sympathetic outflow to adipose tissue. Injections of norepinephrine into the ArcPomc−/− female mice reduced circulating adiponectin levels, whereas injections of propranolol significantly increased adiponectin levels. Despite the beneficial effects of adiponectin on metabolism, the deletion of adiponectin alleles in the ArcPomc−/− mice did not exacerbate their metabolic abnormalities. Conclusion In summary, to the best of our knowledge, this study provides the first evidence that despite obesity, the ArcPomc−/− mouse model has high circulating adiponectin levels, which demonstrated that increased fat mass is not necessarily correlated with hypoadiponectinemia. Our investigation also found a previously unknown physiological pathway connecting POMC neurons via the sympathetic nervous system to circulating adiponectin, thereby shedding light on the biological regulation of adiponectin. Obese female hypothalamic-specific Pomc-deficient mice have unexpectedly elevated circulating adiponectin. Restoration of Pomc expression in the hypothalamus reduces plasma adiponectin. Low sympathetic output to subcutaneous fat depots in the Pomc-deficient mice contributes to high adiponectin levels. Deletion of adiponectin in hypothalamic-specific Pomc-deficient mice does not alter their metabolic phenotype.
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Affiliation(s)
- Hui Yu
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA.
| | - Kavaljit H Chhabra
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA; Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Zoe Thompson
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA
| | - Graham L Jones
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Sylee Kiran
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA; School of Literature, Science, and Arts, University of Michigan, Ann Arbor, MI, USA
| | - Gary Shangguan
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA
| | - Malcolm J Low
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48105, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
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Razolli DS, Moura-Assis A, Bombassaro B, Velloso LA. Hypothalamic neuronal cellular and subcellular abnormalities in experimental obesity. Int J Obes (Lond) 2019; 43:2361-2369. [PMID: 31548571 DOI: 10.1038/s41366-019-0451-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/27/2019] [Accepted: 07/18/2019] [Indexed: 01/15/2023]
Abstract
The characterization of the hypothalamic neuronal network, that controls food intake and energy expenditure, has provided great advances in the understanding of the pathophysiology of obesity. Most of the advances in this field were obtained thanks to the development of a number of genetic and nongenetic animal models that, at least in part, overtook the anatomical constraints that impair the study of the human hypothalamus. Despite the undisputed differences between human and rodent physiology, most seminal studies undertaken in rodents that have unveiled details of the neural regulation of energy homeostasis were eventually confirmed in humans; thus, placing experimental studies in the forefront of obesity research. During the last 15 years, researchers have provided extensive experimental proof that supports the existence of hypothalamic dysfunction, which leads to a progressive whole-body positive energy balance, and thus, to obesity. Here, we review the experimental work that unveiled the mechanisms behind hypothalamic dysfunction in obesity.
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Affiliation(s)
- Daniela S Razolli
- Laboratory of Cell Signaling, Obesity and Comorbidities Center University of Campinas, Campinas, São Paulo, 13084-970, Brazil
| | - Alexandre Moura-Assis
- Laboratory of Cell Signaling, Obesity and Comorbidities Center University of Campinas, Campinas, São Paulo, 13084-970, Brazil
| | - Bruna Bombassaro
- Laboratory of Cell Signaling, Obesity and Comorbidities Center University of Campinas, Campinas, São Paulo, 13084-970, Brazil
| | - Licio A Velloso
- Laboratory of Cell Signaling, Obesity and Comorbidities Center University of Campinas, Campinas, São Paulo, 13084-970, Brazil.
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Jarvela TS, Shakya M, Bachor T, White A, Low MJ, Lindberg I. Reduced Stability and pH-Dependent Activity of a Common Obesity-Linked PCSK1 Polymorphism, N221D. Endocrinology 2019; 160:2630-2645. [PMID: 31504391 PMCID: PMC6892424 DOI: 10.1210/en.2019-00418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/26/2019] [Indexed: 02/06/2023]
Abstract
Common mutations in the human prohormone convertase (PC)1/3 gene (PCKSI) are linked to increased risk of obesity. Previous work has shown that the rs6232 single-nucleotide polymorphism (N221D) results in slightly decreased activity, although whether this decrease underlies obesity risk is not clear. We observed significantly decreased activity of the N221D PC1/3 enzyme at the pH of the trans-Golgi network; at this pH, the mutant enzyme was less stable than wild-type enzyme. Recombinant N221D PC1/3 also showed enhanced susceptibility to heat stress. Enhanced susceptibility to tunicamycin-induced endoplasmic reticulum stress was observed in AtT-20/PC2 cell clones in which murine PC1/3 was replaced by human N221D PC1/3, as compared with wild-type human PC1/3. However, N221D PC1/3-expressing AtT-20/PC2 clones processed proopiomelanocortin to α-MSH similarly to wild-type PC1/3. We also generated a CRISPR-edited mouse line expressing the N221D mutation in the PCKSI gene. When homozygous N221D mice were fed either a standard or a high-fat diet, we found no increase in body weight compared with their wild-type sibling controls. Sexual dimorphism was observed in pituitary ACTH for both genotypes, with females exhibiting lower levels of pituitary ACTH. In contrast, hypothalamic α-MSH content for both genotypes was higher in females compared with males. Hypothalamic corticotropin-like intermediate peptide content was higher in wild-type females compared with wild-type, but not N221D, males. Taken together, these data suggest that the increased obesity risk linked to the N221D allele in humans may be due in part to PC1/3-induced loss of resilience to stressors rather than strictly to decreased enzymatic activity on peptide precursors.
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Affiliation(s)
- Timothy S Jarvela
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Surbhi
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Manita Shakya
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Tomas Bachor
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Anne White
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Malcolm J Low
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Iris Lindberg
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
- Correspondence: Iris Lindberg, PhD, Department of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn Street, Room S267, Baltimore, Maryland 21210. E-mail:
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He Z, Gao Y, Lieu L, Afrin S, Cao J, Michael NJ, Dong Y, Sun J, Guo H, Williams KW. Direct and indirect effects of liraglutide on hypothalamic POMC and NPY/AgRP neurons - Implications for energy balance and glucose control. Mol Metab 2019; 28:120-134. [PMID: 31446151 PMCID: PMC6822260 DOI: 10.1016/j.molmet.2019.07.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 07/22/2019] [Accepted: 07/25/2019] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE The long-acting glucagon-like peptide-1 receptor (GLP-1R) agonist, liraglutide, stimulates insulin secretion and efficiently suppresses food intake to reduce body weight. As such, liraglutide is growing in popularity in the treatment of diabetes and chronic weight management. Within the brain, liraglutide has been shown to alter the activity of hypothalamic proopiomelanocortin (POMC) and Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons. Moreover, the acute activities of POMC and NPY neurons have been directly linked to feeding behavior, body weight, and glucose metabolism. Despite the increased usage of liraglutide and other GLP-1 analogues as diabetic and obesity interventions, the cellular mechanisms by which liraglutide alters the activity of metabolically relevant neuronal populations are poorly understood. METHODS In order to resolve this issue, we utilized neuron-specific transgenic mouse models to identify POMC and NPY neurons for patch-clamp electrophysiology experiments. RESULTS We found that liraglutide directly activated arcuate POMC neurons via TrpC5 channels, sharing a similar mechanistic pathway to the adipose-derived peptide leptin. Liraglutide also indirectly increases excitatory tone to POMC neurons. In contrast, liraglutide inhibited NPY/AgRP neurons through post-synaptic GABAA receptors and enhanced activity of pre-synaptic GABAergic neurons, which required both TrpC5 subunits and K-ATP channels. In support of an additive role of leptin and liraglutide in suppressing food intake, leptin potentiated the acute effects of liraglutide to activate POMC neurons. TrpC5 subunits in POMC neurons were also required for the intact pharmacological effects of liraglutide on food intake and body weight. Thus, the current study adds to recent work from our group and others, which highlight potential mechanisms to amplify the effects of GLP-1 agonists in vivo. Moreover, these data highlight multiple sites of action (both pre- and post-synaptic) for GLP-1 agonists on this circuit. CONCLUSIONS Taken together, our results identify critical molecular mechanisms linking GLP-1 analogues in arcuate POMC and NPY/AgRP neurons with metabolism.
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Affiliation(s)
- Zhenyan He
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China; Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Yong Gao
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA; National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China
| | - Linh Lieu
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Sadia Afrin
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Jianhong Cao
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA; Pi-wei Institute, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China
| | - Natalie J Michael
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Yanbin Dong
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA; Pi-wei Institute, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China
| | - Jia Sun
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Hongbo Guo
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Kevin W Williams
- Division of Hypothalamic Research, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
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67
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Abstract
The discovery of leptin changed the view of adipose tissue from that of a passive vessel that stores fat to that of a dynamic endocrine organ that actively regulates behaviour and metabolism. Secreted by adipose tissue, leptin functions as an afferent signal in a negative feedback loop, acting primarily on neurons in the hypothalamus and regulating feeding and many other functions. The leptin endocrine system serves a critical evolutionary function by maintaining the relative constancy of adipose tissue mass, thereby protecting individuals from the risks associated with being too thin (starvation and infertility) or too obese (predation). In this Review, the biology of leptin is summarized, and a conceptual framework is established for studying the pathogenesis of obesity, which, analogously to diabetes, can result from either leptin hyposecretion or leptin resistance. Herein, these two states are distinguished with the terms 'type 1 obesity' and 'type 2 obesity': type 1 obesity describes a subset of obese individuals with low endogenous plasma leptin levels who respond to leptin therapy, whereas type 2 obesity describes most obese individuals, who are leptin resistant but might respond to leptin therapy in combination with other drugs, such as leptin sensitizers.
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Affiliation(s)
- Jeffrey M Friedman
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA.
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68
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Caron A, Reynolds RP, Castorena CM, Michael NJ, Lee CE, Lee S, Berdeaux R, Scherer PE, Elmquist JK. Adipocyte Gs but not Gi signaling regulates whole-body glucose homeostasis. Mol Metab 2019; 27:11-21. [PMID: 31279640 PMCID: PMC6717754 DOI: 10.1016/j.molmet.2019.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/20/2019] [Accepted: 06/20/2019] [Indexed: 01/24/2023] Open
Abstract
Objective The sympathetic nervous system (SNS) is a key regulator of the metabolic and endocrine functions of adipose tissue. Increased SNS outflow promotes fat mobilization, stimulates non-shivering thermogenesis, promotes browning, and inhibits leptin production. Most of these effects are attributed to norepinephrine activation of the Gs-coupled beta adrenergic receptors located on the surface of the adipocytes. Evidence suggests that other adrenergic receptor subtypes, including the Gi-coupled alpha 2 adrenergic receptors might also mediate the SNS effects on adipose tissue. However, the impact of acute stimulation of adipocyte Gs and Gi has never been reported. Methods We harness the power of chemogenetics to develop unique mouse models allowing the specific and spatiotemporal stimulation of adipose tissue Gi and Gs signaling. We evaluated the impact of chemogenetic stimulation of these pathways on glucose homeostasis, lipolysis, leptin production, and gene expression. Results Stimulation of Gs signaling in adipocytes induced rapid and sustained hypoglycemia. These hypoglycemic effects were secondary to increased insulin release, likely consequent to increased lipolysis. Notably, we also observed differences in gene regulation and ex vivo lipolysis in different adipose depots. In contrast, acute stimulation of Gi signaling in adipose tissue did not affect glucose metabolism or lipolysis, but regulated leptin production. Conclusion Our data highlight the significance of adipose Gs signaling in regulating systemic glucose homeostasis. We also found previously unappreciated heterogeneity across adipose depots following acute stimulation. Together, these results highlight the complex interactions of GPCR signaling in adipose tissue and demonstrate the usefulness of chemogenetic technology to better understand adipocyte function. Chemogenetic stimulation of Gs signaling in adipose tissue potently induces hypoglycemia in mice. The magnitude by which adipose Gs stimulation reduces blood glucose is similar to the hypoglycemic effects of insulin. Chemogenetic stimulation of Gs signaling in adipose tissue ex vivo stimulates lipolysis. Chemogenetic stimulation of adipose Gi signaling does not affect glycemia or lipolysis, but increases leptin levels. Our data demonstrate the usefulness of chemogenetic technology to understand adipocytes functions.
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Affiliation(s)
- Alexandre Caron
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Ryan P Reynolds
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Carlos M Castorena
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Natalie J Michael
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Charlotte E Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Syann Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rebecca Berdeaux
- Department of Integrative Biology and Pharmacology, Center for Metabolic and Degenerative Diseases at the Brown Foundation, Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Graduate Program in Biochemistry and Cell Biology, MD Anderson Cancer Center-UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joel K Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Abstract
Leptin is a key hormone in the homeostatic regulation of body weight. While past research focused mainly on overall leptin actions, a recent study by Dallner et al. (2019) takes a fresh look at the regulatory elements of the leptin gene locus, providing new insights into processes that modulate leptin levels.
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Affiliation(s)
- Heike Münzberg
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA.
| | - Steven B Heymsfield
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
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Yang Y, van der Klaauw AA, Zhu L, Cacciottolo TM, He Y, Stadler LKJ, Wang C, Xu P, Saito K, Hinton A, Yan X, Keogh JM, Henning E, Banton MC, Hendricks AE, Bochukova EG, Mistry V, Lawler KL, Liao L, Xu J, O'Rahilly S, Tong Q, Inês Barroso, O'Malley BW, Farooqi IS, Xu Y. Steroid receptor coactivator-1 modulates the function of Pomc neurons and energy homeostasis. Nat Commun 2019; 10:1718. [PMID: 30979869 PMCID: PMC6461669 DOI: 10.1038/s41467-019-08737-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 01/21/2019] [Indexed: 12/04/2022] Open
Abstract
Hypothalamic neurons expressing the anorectic peptide Pro-opiomelanocortin (Pomc) regulate food intake and body weight. Here, we show that Steroid Receptor Coactivator-1 (SRC-1) interacts with a target of leptin receptor activation, phosphorylated STAT3, to potentiate Pomc transcription. Deletion of SRC-1 in Pomc neurons in mice attenuates their depolarization by leptin, decreases Pomc expression and increases food intake leading to high-fat diet-induced obesity. In humans, fifteen rare heterozygous variants in SRC-1 found in severely obese individuals impair leptin-mediated Pomc reporter activity in cells, whilst four variants found in non-obese controls do not. In a knock-in mouse model of a loss of function human variant (SRC-1L1376P), leptin-induced depolarization of Pomc neurons and Pomc expression are significantly reduced, and food intake and body weight are increased. In summary, we demonstrate that SRC-1 modulates the function of hypothalamic Pomc neurons, and suggest that targeting SRC-1 may represent a useful therapeutic strategy for weight loss.
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Affiliation(s)
- Yongjie Yang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Agatha A van der Klaauw
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Liangru Zhu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Sciences & Technology, Wuhan, 430022, China
| | - Tessa M Cacciottolo
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Yanlin He
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Lukas K J Stadler
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Chunmei Wang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Pingwen Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Kenji Saito
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Antentor Hinton
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Xiaofeng Yan
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Julia M Keogh
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Elana Henning
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Matthew C Banton
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Audrey E Hendricks
- Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
- Mathematical and Statistical Sciences Department, University of Colorado - Denver, Denver, CO, 80204, USA
| | - Elena G Bochukova
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Vanisha Mistry
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Katherine L Lawler
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Lan Liao
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jianming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Stephen O'Rahilly
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | | | - Inês Barroso
- Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
| | - Bert W O'Malley
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - I Sadaf Farooqi
- University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK.
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
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71
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Gustafson P, Ladyman SR, Brown RSE. Suppression of Leptin Transport Into the Brain Contributes to Leptin Resistance During Pregnancy in the Mouse. Endocrinology 2019; 160:880-890. [PMID: 30840056 DOI: 10.1210/en.2018-01065] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 02/27/2019] [Indexed: 11/19/2022]
Abstract
During pregnancy, when both food intake and circulating leptin concentrations increase, the brain becomes insensitive to leptin. The mechanism by which central leptin resistance during pregnancy emerges remains poorly understood. We investigated whether structural changes in the blood-brain barrier (BBB) or changes in carrier-mediated transport of leptin into the brain might contribute to pregnancy-induced leptin resistance. Immunohistochemical evaluation of the BBB at the level of the arcuate nucleus and median eminence in virgin, pregnant, and lactating mice was undertaken by labeling for tanycytes (vimentin), tight junction protein (zona occludens-1), and a marker of fenestrated endothelial capillaries (MECA-32). There were no changes in these BBB markers between virgin, pregnant or lactating mice. Transport of iodine 125-labeled leptin from the peripheral circulation into the brain was completely suppressed during pregnancy, however (days 14 through 16), compared with virgin and lactating (days 7 through 11) mice. This was accompanied by a suppression of leptin clearance from the blood in pregnant mice. We also investigated in virgin mice whether competition with other hormones for transport might contribute to suppression of leptin transport into the brain. Although leptin was able to compete with prolactin transport into the brain, prolactin did not compete with leptin transport. These data demonstrate that suppression of the transport of leptin into the brain during pregnancy, in the absence of structural changes in the BBB, is an important contributor to the insensitivity of the hypothalamus to leptin at this time.
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Affiliation(s)
- Papillon Gustafson
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Sharon R Ladyman
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, New Zealand
| | - Rosemary S E Brown
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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72
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Baldini G, Phelan KD. The melanocortin pathway and control of appetite-progress and therapeutic implications. J Endocrinol 2019; 241:R1-R33. [PMID: 30812013 PMCID: PMC6500576 DOI: 10.1530/joe-18-0596] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 01/22/2019] [Indexed: 12/19/2022]
Abstract
The initial discovery that ob/ob mice become obese because of a recessive mutation of the leptin gene has been crucial to discover the melanocortin pathway to control appetite. In the melanocortin pathway, the fed state is signaled by abundance of circulating hormones such as leptin and insulin, which bind to receptors expressed at the surface of pro-opiomelanocortin (POMC) neurons to promote processing of POMC to the mature hormone α-melanocyte-stimulating hormone (α-MSH). The α-MSH released by POMC neurons then signals to decrease energy intake by binding to melanocortin-4 receptor (MC4R) expressed by MC4R neurons to the paraventricular nucleus (PVN). Conversely, in the 'starved state' activity of agouti-related neuropeptide (AgRP) and of neuropeptide Y (NPY)-expressing neurons is increased by decreased levels of circulating leptin and insulin and by the orexigenic hormone ghrelin to promote food intake. This initial understanding of the melanocortin pathway has recently been implemented by the description of the complex neuronal circuit that controls the activity of POMC, AgRP/NPY and MC4R neurons and downstream signaling by these neurons. This review summarizes the progress done on the melanocortin pathway and describes how obesity alters this pathway to disrupt energy homeostasis. We also describe progress on how leptin and insulin receptors signal in POMC neurons, how MC4R signals and how altered expression and traffic of MC4R change the acute signaling and desensitization properties of the receptor. We also describe how the discovery of the melanocortin pathway has led to the use of melanocortin agonists to treat obesity derived from genetic disorders.
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Affiliation(s)
- Giulia Baldini
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin D. Phelan
- Department of Neurobiology & Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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73
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Cakir I, Diaz-Martinez M, Lining Pan P, Welch EB, Patel S, Ghamari-Langroudi M. Leptin Receptor Signaling in Sim1-Expressing Neurons Regulates Body Temperature and Adaptive Thermogenesis. Endocrinology 2019; 160:863-879. [PMID: 30802281 PMCID: PMC6435012 DOI: 10.1210/en.2019-00062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 02/20/2019] [Indexed: 11/19/2022]
Abstract
Leptin signals to regulate food intake and energy expenditure under conditions of normative energy homeostasis. The central expression and function of leptin receptor B (LepRb) have been extensively studied during the past two decades; however, the mechanisms by which LepRb signaling dysregulation contributes to the pathophysiology of obesity remains unclear. The paraventricular nucleus of the hypothalamus (PVN) plays a crucial role in regulating energy balance as well as the neuroendocrine axes. The role of LepRb expression in the PVN in regard to the regulation of physiological function of leptin has been controversial. The single-minded homolog 1 gene (Sim1) is densely expressed in the PVN and in parts of the amygdala, making Sim1-Cre mice a useful model for examining molecular mechanisms regulating PVN function. In this study, we characterized the physiological role of LepRb in Sim1-expressing neurons using LepRb-floxed × Sim1-Cre mice. Sim1-specific LepRb-deficient mice were surprisingly hypophagic on regular chow but gained more weight upon exposure to a high-fat diet than did their control littermates. We show that Sim1-specific deletion of a single LepRb gene copy caused decreased surface and core body temperatures as well as decreased energy expenditure in ambient room temperatures in both female and male mice. Furthermore, cold-induced adaptive (nonshivering) thermogenesis is disrupted in homozygous knockout mice. A defective thermoregulatory response was associated with defective cold-induced upregulation of uncoupling protein 1 in brown adipose tissue and reduced serum T4. Our study provides novel functional evidence supporting LepRb signaling in Sim1 neurons in the regulation of body weight, core body temperature, and cold-induced adaptive thermogenesis.
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Affiliation(s)
- Isin Cakir
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan
| | - Myriam Diaz-Martinez
- Vanderbilt University Institute of Imaging Science, Vanderbilt University School of Medicine, Nashville, Tennessee
| | | | - E Brian Welch
- Vanderbilt University Institute of Imaging Science, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Sachin Patel
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Masoud Ghamari-Langroudi
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
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74
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Pan W, Allison MB, Sabatini P, Rupp A, Adams J, Patterson C, Jones JC, Olson DP, Myers MG. Transcriptional and physiological roles for STAT proteins in leptin action. Mol Metab 2019; 22:121-131. [PMID: 30718218 PMCID: PMC6437596 DOI: 10.1016/j.molmet.2019.01.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/14/2019] [Accepted: 01/17/2019] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVES Leptin acts via its receptor LepRb on specialized neurons in the brain to modulate food intake, energy expenditure, and body weight. LepRb activates signal transducers and activators of transcription (STATs, including STAT1, STAT3, and STAT5) to control gene expression. METHODS Because STAT3 is crucial for physiologic leptin action, we used TRAP-seq to examine gene expression in LepRb neurons of mice ablated for Stat3 in LepRb neurons (Stat3LepRbKO mice), revealing the STAT3-dependent transcriptional targets of leptin. To understand roles for STAT proteins in leptin action, we also ablated STAT1 or STAT5 from LepRb neurons and expressed a constitutively-active STAT3 (CASTAT3) in LepRb neurons. RESULTS While we also found increased Stat1 expression and STAT1-mediated transcription of leptin-regulated genes in Stat3LepRbKO mice, ablating Stat1 in LepRb neurons failed to alter energy balance (even on the Stat3LepRbKO background); ablating Stat5 in LepRb neurons also failed to alter energy balance. Importantly, expression of a constitutively-active STAT3 (CASTAT3) in LepRb neurons decreased food intake and body weight and improved metabolic parameters in leptin-deficient (ob/ob) mice, as well as in wild-type animals. CONCLUSIONS Thus, STAT3 represents the unique STAT protein required for leptin action and STAT3 suffices to mediate important components of leptin action in the absence of other LepRb signals.
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Affiliation(s)
- Warren Pan
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA
| | - Margaret B Allison
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Paul Sabatini
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Alan Rupp
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Jessica Adams
- Division of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Christa Patterson
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Justin C Jones
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - David P Olson
- Division of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Martin G Myers
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA.
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75
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Furigo IC, Teixeira PDS, de Souza GO, Couto GCL, Romero GG, Perelló M, Frazão R, Elias LL, Metzger M, List EO, Kopchick JJ, Donato J. Growth hormone regulates neuroendocrine responses to weight loss via AgRP neurons. Nat Commun 2019; 10:662. [PMID: 30737388 PMCID: PMC6368581 DOI: 10.1038/s41467-019-08607-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 12/10/2018] [Indexed: 11/11/2022] Open
Abstract
Weight loss triggers important metabolic responses to conserve energy, especially via the fall in leptin levels. Consequently, weight loss becomes increasingly difficult with weight regain commonly occurring in most dieters. Here we show that central growth hormone (GH) signaling also promotes neuroendocrine adaptations during food deprivation. GH activates agouti-related protein (AgRP) neurons and GH receptor (GHR) ablation in AgRP cells mitigates highly characteristic hypothalamic and metabolic adaptations induced by weight loss. Thus, the capacity of mice carrying an AgRP-specific GHR ablation to save energy during food deprivation is impaired, leading to increased fat loss. Additionally, administration of a clinically available GHR antagonist (pegvisomant) attenuates the fall of whole-body energy expenditure of food-deprived mice, similarly as seen by leptin treatment. Our findings indicate GH as a starvation signal that alerts the brain about energy deficiency, triggering key adaptive responses to conserve limited fuel stores. Reduction in food intake elicits neuroendocrine adaptations to counterregulate the negative energy balance, e.g. via reduction in leptin levels. Here, the authors identify an additional starvation signal, growth hormone (GH). Blocking GH receptor attenuates the fall of whole body energy expenditure during food deprivation in mice.
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Affiliation(s)
- Isadora C Furigo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil
| | - Pryscila D S Teixeira
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil
| | - Gabriel O de Souza
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil
| | - Gisele C L Couto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil
| | - Guadalupe García Romero
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil.,Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, Calle 526 y Camino General Belgrano, La Plata, BA, 1900, Argentina
| | - Mario Perelló
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, Calle 526 y Camino General Belgrano, La Plata, BA, 1900, Argentina
| | - Renata Frazão
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 2415, São Paulo, SP, 05508-900, Brazil
| | - Lucila L Elias
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, SP, 14049-900, Brazil
| | - Martin Metzger
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Konneker Research Center 206A, Athens, OH, 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Konneker Research Center 206A, Athens, OH, 45701, USA
| | - J Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1524, São Paulo, SP, 05508-000, Brazil.
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76
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Flier JS. Starvation in the Midst of Plenty: Reflections on the History and Biology of Insulin and Leptin. Endocr Rev 2019; 40:1-16. [PMID: 30357355 PMCID: PMC6270967 DOI: 10.1210/er.2018-00179] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/13/2018] [Indexed: 02/08/2023]
Abstract
Insulin and leptin are critical metabolic hormones that play essential but distinct roles in regulating the physiologic switch between the fed and starved states. The discoveries of insulin and leptin, in 1922 and 1994, respectively, arose out of radically different scientific environments. Despite the dearth of scientific tools available in 1922, insulin's discovery rapidly launched a life-saving therapy for what we now know to be type I diabetes, and continually enhanced insulin therapeutics are now effectively applied to both major forms of this increasingly prevalent disease. In contrast, although the discovery of leptin provided deep insights into the regulation of central nervous system energy balance circuits, as well as an effective therapy for an extremely rare form of obesity, its therapeutic impact beyond that has been surprisingly limited. Despite an enormous accumulated body of information, many important questions remain unanswered about the mechanisms of action and role in disease of both hormones. Additionally, although many decades apart, both discoveries reveal the complexities inherent to scientific collaboration and the assignment of credit, even when the efforts are spectacularly successful.
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Affiliation(s)
- Jeffrey S Flier
- Department of Medicine and Department of Neurobiology, Harvard Medical School, Boston, Massachusetts
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77
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Smith MA, Katsouri L, Virtue S, Choudhury AI, Vidal-Puig A, Ashford MLJ, Withers DJ. Calcium Channel Ca V2.3 Subunits Regulate Hepatic Glucose Production by Modulating Leptin-Induced Excitation of Arcuate Pro-opiomelanocortin Neurons. Cell Rep 2018; 25:278-287.e4. [PMID: 30304668 PMCID: PMC6198286 DOI: 10.1016/j.celrep.2018.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 07/26/2018] [Accepted: 09/07/2018] [Indexed: 11/18/2022] Open
Abstract
Leptin acts on hypothalamic pro-opiomelanocortin (POMC) neurons to regulate glucose homeostasis, but the precise mechanisms remain unclear. Here, we demonstrate that leptin-induced depolarization of POMC neurons is associated with the augmentation of a voltage-gated calcium (CaV) conductance with the properties of the "R-type" channel. Knockdown of the pore-forming subunit of the R-type (CaV2.3 or Cacna1e) conductance in hypothalamic POMC neurons prevented sustained leptin-induced depolarization. In vivo POMC-specific Cacna1e knockdown increased hepatic glucose production and insulin resistance, while body weight, feeding, or leptin-induced suppression of food intake were not changed. These findings link Cacna1e function to leptin-mediated POMC neuron excitability and glucose homeostasis and may provide a target for the treatment of diabetes.
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Affiliation(s)
- Mark A Smith
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK.
| | - Loukia Katsouri
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK
| | - Samuel Virtue
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Agharul I Choudhury
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK
| | - Antonio Vidal-Puig
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Michael L J Ashford
- Division of Molecular and Clinical Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Dominic J Withers
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK; Institute of Clinical Sciences, Imperial College London, Du Cane Road, London W12 0NN, UK.
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78
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Dodd GT, Michael NJ, Lee-Young RS, Mangiafico SP, Pryor JT, Munder AC, Simonds SE, Brüning JC, Zhang ZY, Cowley MA, Andrikopoulos S, Horvath TL, Spanswick D, Tiganis T. Insulin regulates POMC neuronal plasticity to control glucose metabolism. eLife 2018; 7:38704. [PMID: 30230471 PMCID: PMC6170188 DOI: 10.7554/elife.38704] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 09/14/2018] [Indexed: 11/30/2022] Open
Abstract
Hypothalamic neurons respond to nutritional cues by altering gene expression and neuronal excitability. The mechanisms that control such adaptive processes remain unclear. Here we define populations of POMC neurons in mice that are activated or inhibited by insulin and thereby repress or inhibit hepatic glucose production (HGP). The proportion of POMC neurons activated by insulin was dependent on the regulation of insulin receptor signaling by the phosphatase TCPTP, which is increased by fasting, degraded after feeding and elevated in diet-induced obesity. TCPTP-deficiency enhanced insulin signaling and the proportion of POMC neurons activated by insulin to repress HGP. Elevated TCPTP in POMC neurons in obesity and/or after fasting repressed insulin signaling, the activation of POMC neurons by insulin and the insulin-induced and POMC-mediated repression of HGP. Our findings define a molecular mechanism for integrating POMC neural responses with feeding to control glucose metabolism.
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Affiliation(s)
- Garron T Dodd
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Natalie J Michael
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Physiology, Monash University, Victoria, Australia
| | - Robert S Lee-Young
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia.,Monash Metabolic Phenotyping Facility, Monash University, Victoria, Australia
| | - Salvatore P Mangiafico
- Department of Medicine (Austin Hospital), The University of Melbourne, Melbourne, Australia
| | - Jack T Pryor
- Department of Physiology, Monash University, Victoria, Australia.,Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Astrid C Munder
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Physiology, Monash University, Victoria, Australia
| | - Stephanie E Simonds
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Physiology, Monash University, Victoria, Australia
| | - Jens Claus Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany.,Center for Endocrinology, Diabetes, and Preventive Medicine, University Hospital Cologne, Cologne, Germany.,Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany.,Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,National Center for Diabetes Research, Neuherberg, Germany
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, United States
| | - Michael A Cowley
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Physiology, Monash University, Victoria, Australia
| | - Sofianos Andrikopoulos
- Department of Medicine (Austin Hospital), The University of Melbourne, Melbourne, Australia
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, United States.,Department of Anatomy and Histology, University of Veterinary Medicine, Hungary, Europe
| | - David Spanswick
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Physiology, Monash University, Victoria, Australia.,Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Tony Tiganis
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia.,Monash Metabolic Phenotyping Facility, Monash University, Victoria, Australia
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