1
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Thorens B. Neuronal glucose sensing mechanisms and circuits in the control of insulin and glucagon secretion. Physiol Rev 2024; 104:1461-1486. [PMID: 38661565 DOI: 10.1152/physrev.00038.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 04/16/2024] [Accepted: 04/20/2024] [Indexed: 04/26/2024] Open
Abstract
Glucose homeostasis is mainly under the control of the pancreatic islet hormones insulin and glucagon, which, respectively, stimulate glucose uptake and utilization by liver, fat, and muscle and glucose production by the liver. The balance between the secretions of these hormones is under the control of blood glucose concentrations. Indeed, pancreatic islet β-cells and α-cells can sense variations in glycemia and respond by an appropriate secretory response. However, the secretory activity of these cells is also under multiple additional metabolic, hormonal, and neuronal signals that combine to ensure the perfect control of glycemia over a lifetime. The central nervous system (CNS), which has an almost absolute requirement for glucose as a source of metabolic energy and thus a vital interest in ensuring that glycemic levels never fall below ∼5 mM, is equipped with populations of neurons responsive to changes in glucose concentrations. These neurons control pancreatic islet cell secretion activity in multiple ways: through both branches of the autonomic nervous system, through the hypothalamic-pituitary-adrenal axis, and by secreting vasopressin (AVP) in the blood at the level of the posterior pituitary. Here, we present the autonomic innervation of the pancreatic islets; the mechanisms of neuron activation by a rise or a fall in glucose concentration; how current viral tracing, chemogenetic, and optogenetic techniques allow integration of specific glucose sensing neurons in defined neuronal circuits that control endocrine pancreas function; and, finally, how genetic screens in mice can untangle the diversity of the hypothalamic mechanisms controlling the response to hypoglycemia.
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Affiliation(s)
- Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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2
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Vertiprakhov VG, Grozina AA, Fisinin VI, Surai PF. Adaptation of chicken pancreatic secretory functions to feed composition. WORLD POULTRY SCI J 2023. [DOI: 10.1080/00439339.2023.2163042] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- V. G. Vertiprakhov
- Moscow Timiryazev Agricultural Academy, Russian State Agrarian University, Moscow, Russia
| | - A. A. Grozina
- Department of Physiology and Biochemistry, Federal Scientific Center “All-Russian Research and Technological Poultry Institute” of Russian Academy of Sciences, Sergiev Posad, Russia
| | - V. I. Fisinin
- Department of Physiology and Biochemistry, Federal Scientific Center “All-Russian Research and Technological Poultry Institute” of Russian Academy of Sciences, Sergiev Posad, Russia
| | - P. F. Surai
- Department of Biochemistry, Vitagene and Health Research Centre, Bristol, UK
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3
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Verberne AJM, Mussa BM. Neural control of pancreatic peptide hormone secretion. Peptides 2022; 152:170768. [PMID: 35189258 DOI: 10.1016/j.peptides.2022.170768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/10/2022] [Accepted: 02/12/2022] [Indexed: 11/20/2022]
Abstract
Pancreatic peptide hormone secretion is inextricably linked to maintenance of normal levels of blood glucose. In animals and man, pancreatic peptide hormone secretion is controlled, at least in part, by input from parasympathetic (vagal) premotor neurons that are found principally in the dorsal motor nucleus of the vagus (DMV). Iatrogenic (insulin-induced) hypoglycaemia evokes a homeostatic response commonly referred to as the glucose counter-regulatory response. This homeostatic response is of particular importance in Type 1 diabetes in which episodes of hypoglycaemia are common, debilitating and lead to suboptimal control of blood glucose. Glucagon is the principal counterregulatory hormone but for reasons unknown, its secretion during insulin-induced hypoglycaemia is impaired. Pancreatic parasympathetic neurons are distinguishable electrophysiologically from those that control other (e.g. gastric) functions and are controlled by supramedullary inputs from hypothalamic structures such as the perifornical region. During hypoglycaemia, glucose-sensitive, GABAergic neurons in the ventromedial hypothalamus are inhibited leading to disinhibition of perifornical orexin neurons with projections to the DMV which, in turn, leads to increased secretion of glucagon.
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Affiliation(s)
- Anthony J M Verberne
- Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria 3084, Australia.
| | - Bashair M Mussa
- Basic Medical Science Department, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
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4
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Gasparini G, Pellegatta M, Crippa S, Lena MS, Belfiori G, Doglioni C, Taveggia C, Falconi M. Nerves and Pancreatic Cancer: New Insights into a Dangerous Relationship. Cancers (Basel) 2019; 11:E893. [PMID: 31248001 PMCID: PMC6678884 DOI: 10.3390/cancers11070893] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/21/2019] [Accepted: 06/24/2019] [Indexed: 12/24/2022] Open
Abstract
Perineural invasion (PNI) is defined as the presence of neoplastic cells along nerves and/or within the different layers of nervous fibers: epineural, perineural and endoneural spaces. In pancreatic cancer-particularly in pancreatic ductal adenocarcinoma (PDAC)-PNI has a prevalence between 70 and 100%, surpassing any other solid tumor. PNI has been detected in the early stages of pancreatic cancer and has been associated with pain, increased tumor recurrence and diminished overall survival. Such an early, invasive and recurrent phenomenon is probably crucial for tumor growth and metastasis. PNI is a still not a uniformly characterized event; usually it is described only dichotomously ("present" or "absent"). Recently, a more detailed scoring system for PNI has been proposed, though not specific for pancreatic cancer. Previous studies have implicated several molecules and pathways in PNI, among which are secreted neurotrophins, chemokines and inflammatory cells. However, the mechanisms underlying PNI are poorly understood and several aspects are actively being investigated. In this review, we will discuss the main molecules and signaling pathways implicated in PNI and their roles in the PDAC.
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Affiliation(s)
- Giulia Gasparini
- Pancreas Translational & Clinical Research Center, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
- Axo-Glial Interaction Unit, INSPE, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Marta Pellegatta
- Axo-Glial Interaction Unit, INSPE, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Stefano Crippa
- Pancreas Translational & Clinical Research Center, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
- Vita Salute San Raffaele University, 20132 Milan, Italy.
| | - Marco Schiavo Lena
- Pathology Unit, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Giulio Belfiori
- Pancreas Translational & Clinical Research Center, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Claudio Doglioni
- Vita Salute San Raffaele University, 20132 Milan, Italy.
- Pathology Unit, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Carla Taveggia
- Axo-Glial Interaction Unit, INSPE, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Massimo Falconi
- Pancreas Translational & Clinical Research Center, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
- Vita Salute San Raffaele University, 20132 Milan, Italy.
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5
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Scarlett JM, Muta K, Brown JM, Rojas JM, Matsen ME, Acharya NK, Secher A, Ingvorsen C, Jorgensen R, Høeg-Jensen T, Stefanovski D, Bergman RN, Piccinini F, Kaiyala KJ, Shiota M, Morton GJ, Schwartz MW. Peripheral Mechanisms Mediating the Sustained Antidiabetic Action of FGF1 in the Brain. Diabetes 2019; 68:654-664. [PMID: 30523024 PMCID: PMC6385755 DOI: 10.2337/db18-0498] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 10/29/2018] [Indexed: 12/24/2022]
Abstract
We recently reported that in rodent models of type 2 diabetes (T2D), a single intracerebroventricular (icv) injection of fibroblast growth factor 1 (FGF1) induces remission of hyperglycemia that is sustained for weeks. To clarify the peripheral mechanisms underlying this effect, we used the Zucker diabetic fatty fa/fa rat model of T2D, which, like human T2D, is characterized by progressive deterioration of pancreatic β-cell function after hyperglycemia onset. We report that although icv FGF1 injection delays the onset of β-cell dysfunction in these animals, it has no effect on either glucose-induced insulin secretion or insulin sensitivity. These observations suggest that FGF1 acts in the brain to stimulate insulin-independent glucose clearance. On the basis of our finding that icv FGF1 treatment increases hepatic glucokinase gene expression, we considered the possibility that increased hepatic glucose uptake (HGU) contributes to the insulin-independent glucose-lowering effect of icv FGF1. Consistent with this possibility, we report that icv FGF1 injection increases liver glucokinase activity by approximately twofold. We conclude that sustained remission of hyperglycemia induced by the central action of FGF1 involves both preservation of β-cell function and stimulation of HGU through increased hepatic glucokinase activity.
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Affiliation(s)
- Jarrad M Scarlett
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
- Gastroenterology and Hepatology, Department of Pediatrics, University of Washington, Seattle, WA
| | - Kenjiro Muta
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
| | - Jenny M Brown
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
| | - Jennifer M Rojas
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
- Department of Physiology, Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Miles E Matsen
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
| | - Nikhil K Acharya
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
| | | | | | | | | | - Darko Stefanovski
- New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
| | - Richard N Bergman
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Francesca Piccinini
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Karl J Kaiyala
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA
| | - Masakazu Shiota
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Gregory J Morton
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
| | - Michael W Schwartz
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA
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6
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García-García A, Korn C, García-Fernández M, Domingues O, Villadiego J, Martín-Pérez D, Isern J, Bejarano-García JA, Zimmer J, Pérez-Simón JA, Toledo-Aral JJ, Michel T, Airaksinen MS, Méndez-Ferrer S. Dual cholinergic signals regulate daily migration of hematopoietic stem cells and leukocytes. Blood 2019; 133:224-236. [PMID: 30361261 PMCID: PMC6449569 DOI: 10.1182/blood-2018-08-867648] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 10/02/2018] [Indexed: 12/12/2022] Open
Abstract
Hematopoietic stem and progenitor cells (HSPCs) and leukocytes circulate between the bone marrow (BM) and peripheral blood following circadian oscillations. Autonomic sympathetic noradrenergic signals have been shown to regulate HSPC and leukocyte trafficking, but the role of the cholinergic branch has remained unexplored. We have investigated the role of the cholinergic nervous system in the regulation of day/night traffic of HSPCs and leukocytes in mice. We show here that the autonomic cholinergic nervous system (including parasympathetic and sympathetic) dually regulates daily migration of HSPCs and leukocytes. At night, central parasympathetic cholinergic signals dampen sympathetic noradrenergic tone and decrease BM egress of HSPCs and leukocytes. However, during the daytime, derepressed sympathetic noradrenergic activity causes predominant BM egress of HSPCs and leukocytes via β3-adrenergic receptor. This egress is locally supported by light-triggered sympathetic cholinergic activity, which inhibits BM vascular cell adhesion and homing. In summary, central (parasympathetic) and local (sympathetic) cholinergic signals regulate day/night oscillations of circulating HSPCs and leukocytes. This study shows how both branches of the autonomic nervous system cooperate to orchestrate daily traffic of HSPCs and leukocytes.
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MESH Headings
- Animals
- Bone Marrow Cells/cytology
- Bone Marrow Cells/drug effects
- Bone Marrow Cells/physiology
- Cell Adhesion
- Cell Movement
- Cells, Cultured
- Chemotaxis
- Cholinergic Agents/pharmacology
- Circadian Rhythm
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiology
- Female
- Glial Cell Line-Derived Neurotrophic Factor Receptors/physiology
- Hematopoietic Stem Cells/cytology
- Hematopoietic Stem Cells/drug effects
- Hematopoietic Stem Cells/physiology
- Leukocytes/cytology
- Leukocytes/drug effects
- Leukocytes/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Parasympathetic Nervous System/physiology
- Receptors, Adrenergic, beta-2
- Receptors, Adrenergic, beta-3/physiology
- Receptors, G-Protein-Coupled/physiology
- Sympathetic Nervous System/physiology
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Affiliation(s)
- Andrés García-García
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Hematology, University of Cambridge, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Claudia Korn
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Hematology, University of Cambridge, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - María García-Fernández
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Hematology, University of Cambridge, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Olivia Domingues
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur Alzette, Luxembourg
| | - Javier Villadiego
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC) and
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Seville, Spain; and
| | | | - Joan Isern
- Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - José A Bejarano-García
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC) and
| | - Jacques Zimmer
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur Alzette, Luxembourg
| | - José A Pérez-Simón
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC) and
| | - Juan J Toledo-Aral
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC) and
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Seville, Spain; and
| | - Tatiana Michel
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur Alzette, Luxembourg
| | - Matti S Airaksinen
- Neuroscience Center and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Simón Méndez-Ferrer
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Hematology, University of Cambridge, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
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7
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Mu W, Wang Z, Zöller M. Ping-Pong-Tumor and Host in Pancreatic Cancer Progression. Front Oncol 2019; 9:1359. [PMID: 31921628 PMCID: PMC6927459 DOI: 10.3389/fonc.2019.01359] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 11/18/2019] [Indexed: 12/12/2022] Open
Abstract
Metastasis is the main cause of high pancreatic cancer (PaCa) mortality and trials dampening PaCa mortality rates are not satisfying. Tumor progression is driven by the crosstalk between tumor cells, predominantly cancer-initiating cells (CIC), and surrounding cells and tissues as well as distant organs, where tumor-derived extracellular vesicles (TEX) are of major importance. A strong stroma reaction, recruitment of immunosuppressive leukocytes, perineural invasion, and early spread toward the peritoneal cavity, liver, and lung are shared with several epithelial cell-derived cancer, but are most prominent in PaCa. Here, we report on the state of knowledge on the PaCIC markers Tspan8, alpha6beta4, CD44v6, CXCR4, LRP5/6, LRG5, claudin7, EpCAM, and CD133, which all, but at different steps, are engaged in the metastatic cascade, frequently via PaCIC-TEX. This includes the contribution of PaCIC markers to TEX biogenesis, targeting, and uptake. We then discuss PaCa-selective features, where feedback loops between stromal elements and tumor cells, including distorted transcription, signal transduction, and metabolic shifts, establish vicious circles. For the latter particularly pancreatic stellate cells (PSC) are responsible, furnishing PaCa to cope with poor angiogenesis-promoted hypoxia by metabolic shifts and direct nutrient transfer via vesicles. Furthermore, nerves including Schwann cells deliver a large range of tumor cell attracting factors and Schwann cells additionally support PaCa cell survival by signaling receptor binding. PSC, tumor-associated macrophages, and components of the dysplastic stroma contribute to perineural invasion with signaling pathway activation including the cholinergic system. Last, PaCa aggressiveness is strongly assisted by the immune system. Although rich in immune cells, only immunosuppressive cells and factors are recovered in proximity to tumor cells and hamper effector immune cells entering the tumor stroma. Besides a paucity of immunostimulatory factors and receptors, immunosuppressive cytokines, myeloid-derived suppressor cells, regulatory T-cells, and M2 macrophages as well as PSC actively inhibit effector cell activation. This accounts for NK cells of the non-adaptive and cytotoxic T-cells of the adaptive immune system. We anticipate further deciphering the molecular background of these recently unraveled intermingled phenomena may turn most lethal PaCa into a curatively treatable disease.
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Affiliation(s)
- Wei Mu
- School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- *Correspondence: Wei Mu
| | - Zhe Wang
- Department of Oncology, The First Affiliated Hospital of Guangdong, Pharmaceutical University, Guangzhou, China
| | - Margot Zöller
- Department of Oncology, The First Affiliated Hospital of Guangdong, Pharmaceutical University, Guangzhou, China
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8
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Jin S, Diano S. Mitochondrial Dynamics and Hypothalamic Regulation of Metabolism. Endocrinology 2018; 159:3596-3604. [PMID: 30203064 PMCID: PMC6157417 DOI: 10.1210/en.2018-00667] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 09/02/2018] [Indexed: 01/22/2023]
Abstract
Mitochondria are cellular organelles that play an important role in bioenergetic processes. In the central nervous system, high energy-demanding neurons are critically dependent on mitochondria to fulfill their appropriate functions. The hypothalamus is a key brain area for maintaining glucose and energy homeostasis via the ability of hypothalamic neurons to sense, integrate, and respond to numerous metabolic signals. Mitochondrial function has emerged as an important component in the regulation of hypothalamic neurons controlling glucose and energy homeostasis. Although the underlying mechanisms are not fully understood, emerging evidence indicates that mitochondrial dysfunction in hypothalamic neurons may contribute to the development of various metabolic diseases, including obesity and type 2 diabetes mellitus (T2DM). In this review, we summarize recent studies demonstrating the link between mitochondria and hypothalamic neural control of glucose and energy homeostasis. Finally, this review provides an insight to understand how mitochondria in hypothalamic neurons may contribute to the development of metabolic disorders, such as T2DM and obesity.
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Affiliation(s)
- Sungho Jin
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut
| | - Sabrina Diano
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut
- Department of Clinical Medicine and Surgery, University of Naples “Federico II,” Naples, Italy
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9
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Watabe K, Yokawa S, Inoh Y, Suzuki T, Furuno T. Decreased intracellular granule movement and glucagon secretion in pancreatic α cells attached to superior cervical ganglion neurites. Mol Cell Biochem 2018; 446:83-89. [PMID: 29318457 DOI: 10.1007/s11010-018-3275-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/04/2018] [Indexed: 11/25/2022]
Abstract
Autonomic neurons innervate pancreatic islets of Langerhans and participate in the maintenance of blood glucose concentrations by controlling hormone levels through attachment with islet cells. We previously found that stimulated superior cervical ganglia (SCG) could induce Ca2+ oscillation in α cells via neuropeptide substance P using an in vitro co-culture model. In this study, we studied the effect of SCG neurite adhesion on intracellular secretory granule movement and glucagon secretion in α cells stimulated by low glucose concentration. Spinning disk microscopic analysis revealed that the mean velocity of intracellular granules was significantly lower in α cells attached to SCG neurites than that in those without neurites under low (2 mM), middle (10 mM), and high (20 mM) glucose concentrations. Stimulation by a low (2 mM) glucose concentration significantly increased glucagon secretion in α cells lacking neurites but not in those bound to neurites. These results suggest that adhesion to SCG neurites decreases low glucose-induced glucagon secretion in pancreatic α cells by attenuating intracellular granule movement activity.
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Affiliation(s)
- Kiyoto Watabe
- School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan
| | - Satoru Yokawa
- School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan
| | - Yoshikazu Inoh
- School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan
| | - Takahiro Suzuki
- School of Dentistry, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan
| | - Tadahide Furuno
- School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan.
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10
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Jessen L, Smith EP, Ulrich-Lai Y, Herman JP, Seeley RJ, Sandoval D, D’Alessio D. Central Nervous System GLP-1 Receptors Regulate Islet Hormone Secretion and Glucose Homeostasis in Male Rats. Endocrinology 2017; 158:2124-2133. [PMID: 28430981 PMCID: PMC5505222 DOI: 10.1210/en.2016-1826] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 04/13/2017] [Indexed: 02/07/2023]
Abstract
The glucagon-like peptide 1 (GLP-1) system plays an important role in blood glucose regulation, in great part through coordinate control of insulin and glucagon secretion. These effects are generally attributed to GLP-1 produced in peripheral sites, principally the intestine. GLP-1 is also produced in hindbrain neurons that signal through GLP-1 receptors (GLP-1rs) expressed in brain regions involved in metabolic regulation. GLP-1 in the central nervous system (CNS) induces satiety, visceral illness, and stress responses. However, recent evidence suggests CNS GLP-1 is also involved in glucose regulation. To test the hypothesis that central GLP-1 regulates islet hormone secretion, conscious rats were given intracerebroventricular (ICV) GLP-1, GLP-1r antagonist exendin-[9-39] (Ex-9), or saline during fasting or hyperglycemia from intravenous glucose. Administration of CNS GLP-1 increased fasting glucose, glucagon, corticosterone, and epinephrine and blunted insulin secretion in response to hyperglycemia. Paradoxically, GLP-1r blockade with ICV Ex-9 also reduced glucose-stimulated insulin secretion, and administration of ICV Ex-9 to freely feeding rats caused mild glucose intolerance. Thus, direct administration of CNS GLP-1 affected islet hormone secretion counter to what is seen with peripherally administered GLP-1, an effect likely due to stimulation of sympathetic nervous system activity. In contrast, blockade of brain GLP-1r supports a role for CNS GLP-1 on glucose-stimulated insulin secretion and glucose control after a meal. These findings suggest a model in which activation of CNS GLP-1r by endogenous peptide promotes glucose tolerance, an effect that can be overridden by stress responses stimulated by exogenous GLP-1.
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Affiliation(s)
- Lene Jessen
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45219
| | - Eric P. Smith
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45219
| | - Yvonne Ulrich-Lai
- Department of Psychiatry and Behavioral Neursocience, University of Cincinnati, Cincinnati, Ohio 45219
| | - James P. Herman
- Department of Psychiatry and Behavioral Neursocience, University of Cincinnati, Cincinnati, Ohio 45219
| | - Randy J. Seeley
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45219
| | - Darleen Sandoval
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45219
| | - David D’Alessio
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45219
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11
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Trevaskis JL, Sacramento CB, Jouihan H, Ali S, Le Lay J, Oldham S, Bhagroo N, Boland BB, Cann J, Chang Y, O'Day T, Howard V, Reers C, Winzell MS, Smith DM, Feigh M, Barkholt P, Schreiter K, Austen M, Andag U, Thompson S, Jermutus L, Coghlan MP, Grimsby J, Dohrmann C, Rhodes CJ, Rondinone CM, Sharma A. Neurturin and a GLP-1 Analogue Act Synergistically to Alleviate Diabetes in Zucker Diabetic Fatty Rats. Diabetes 2017; 66:2007-2018. [PMID: 28408435 DOI: 10.2337/db16-0916] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 04/05/2017] [Indexed: 11/13/2022]
Abstract
Neurturin (NRTN), a member of the glial-derived neurotrophic factor family, was identified from an embryonic chicken pancreatic cDNA library in a screen for secreted factors. In this study, we assessed the potential antidiabetic activities of NRTN relative to liraglutide, a glucagon-like peptide 1 receptor agonist, in Zucker diabetic fatty (ZDF) rats. Subcutaneous administration of NRTN to 8-week-old male ZDF rats prevented the development of hyperglycemia and improved metabolic parameters similar to liraglutide. NRTN treatment increased pancreatic insulin content and β-cell mass and prevented deterioration of islet organization. However, unlike liraglutide-treated rats, NRTN-mediated improvements were not associated with reduced body weight or food intake. Acute NRTN treatment did not activate c-Fos expression in key feeding behavior and metabolic centers in ZDF rat brain or directly enhance glucose-stimulated insulin secretion from pancreatic β-cells. Treating 10-week-old ZDF rats with sustained hyperglycemia with liraglutide resulted in some alleviation of hyperglycemia, whereas NRTN was not as effective despite improving plasma lipids and fasting glucose levels. Interestingly, coadministration of NRTN and liraglutide normalized hyperglycemia and other metabolic parameters, demonstrating that combining therapies with distinct mechanism(s) can alleviate advanced diabetes. This emphasizes that therapeutic combinations can be more effective to manage diabetes in individuals with uncontrolled hyperglycemia.
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Affiliation(s)
- James L Trevaskis
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | - Hani Jouihan
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Safina Ali
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - John Le Lay
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Stephanie Oldham
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Nicholas Bhagroo
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Brandon B Boland
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Jennifer Cann
- Translational Sciences (Pathology), MedImmune LLC, Gaithersburg, MD
| | - Yuan Chang
- Biopharmaceutical Development, MedImmune LLC, Gaithersburg, MD
| | | | - Victor Howard
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | | | - David M Smith
- Discovery Sciences, Innovative Medicines & Early Development Biotech Unit, AstraZeneca, Cambridge, U.K
| | | | | | | | | | | | - Simon Thompson
- Research Project and Portfolio Management, MedImmune Ltd., Cambridge, U.K
| | - Lutz Jermutus
- Department of Cardiovascular and Metabolic Diseases, MedImmune Ltd., Cambridge, U.K
| | - Matthew P Coghlan
- Department of Cardiovascular and Metabolic Diseases, MedImmune Ltd., Cambridge, U.K
| | - Joseph Grimsby
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | - Christopher J Rhodes
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Cristina M Rondinone
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Arun Sharma
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
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12
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Fournel A, Marlin A, Abot A, Pasquio C, Cirillo C, Cani PD, Knauf C. Glucosensing in the gastrointestinal tract: Impact on glucose metabolism. Am J Physiol Gastrointest Liver Physiol 2016; 310:G645-58. [PMID: 26939867 PMCID: PMC4867329 DOI: 10.1152/ajpgi.00015.2016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/25/2016] [Indexed: 01/31/2023]
Abstract
The gastrointestinal tract is an important interface of exchange between ingested food and the body. Glucose is one of the major dietary sources of energy. All along the gastrointestinal tube, e.g., the oral cavity, small intestine, pancreas, and portal vein, specialized cells referred to as glucosensors detect variations in glucose levels. In response to this glucose detection, these cells send hormonal and neuronal messages to tissues involved in glucose metabolism to regulate glycemia. The gastrointestinal tract continuously communicates with the brain, especially with the hypothalamus, via the gut-brain axis. It is now well established that the cross talk between the gut and the brain is of crucial importance in the control of glucose homeostasis. In addition to receiving glucosensing information from the gut, the hypothalamus may also directly sense glucose. Indeed, the hypothalamus contains glucose-sensitive cells that regulate glucose homeostasis by sending signals to peripheral tissues via the autonomous nervous system. This review summarizes the mechanisms by which glucosensors along the gastrointestinal tract detect glucose, as well as the results of such detection in the whole body, including the hypothalamus. We also highlight how disturbances in the glucosensing process may lead to metabolic disorders such as type 2 diabetes. A better understanding of the pathways regulating glucose homeostasis will further facilitate the development of novel therapeutic strategies for the treatment of metabolic diseases.
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Affiliation(s)
- Audren Fournel
- 1NeuroMicrobiota, European Associated Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) U1220, Institut de Recherche en Santé Digestive (IRSD), Toulouse, France;
| | - Alysson Marlin
- 1NeuroMicrobiota, European Associated Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) U1220, Institut de Recherche en Santé Digestive (IRSD), Toulouse, France;
| | - Anne Abot
- 1NeuroMicrobiota, European Associated Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) U1220, Institut de Recherche en Santé Digestive (IRSD), Toulouse, France;
| | - Charles Pasquio
- 1NeuroMicrobiota, European Associated Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) U1220, Institut de Recherche en Santé Digestive (IRSD), Toulouse, France;
| | - Carla Cirillo
- 2Laboratory for Enteric NeuroScience (LENS), University of Leuven, Leuven, Belgium; and
| | - Patrice D. Cani
- 3NeuroMicrobiota, European Associated Laboratory, Université Catholique de Louvain (UCL), Louvain Drug Research Institute (LDRI), Metabolism and Nutrition Research Group, WELBIO (Walloon Excellence in Life sciences and BIOtechnology), Brussels, Belgium
| | - Claude Knauf
- NeuroMicrobiota, European Associated Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) U1220, Institut de Recherche en Santé Digestive (IRSD), Toulouse, France;
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13
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Röder PV, Wu B, Liu Y, Han W. Pancreatic regulation of glucose homeostasis. Exp Mol Med 2016; 48:e219. [PMID: 26964835 PMCID: PMC4892884 DOI: 10.1038/emm.2016.6] [Citation(s) in RCA: 467] [Impact Index Per Article: 58.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 12/03/2015] [Accepted: 12/06/2015] [Indexed: 12/11/2022] Open
Abstract
In order to ensure normal body function, the human body is dependent on a tight control of its blood glucose levels. This is accomplished by a highly sophisticated network of various hormones and neuropeptides released mainly from the brain, pancreas, liver, intestine as well as adipose and muscle tissue. Within this network, the pancreas represents a key player by secreting the blood sugar-lowering hormone insulin and its opponent glucagon. However, disturbances in the interplay of the hormones and peptides involved may lead to metabolic disorders such as type 2 diabetes mellitus (T2DM) whose prevalence, comorbidities and medical costs take on a dramatic scale. Therefore, it is of utmost importance to uncover and understand the mechanisms underlying the various interactions to improve existing anti-diabetic therapies and drugs on the one hand and to develop new therapeutic approaches on the other. This review summarizes the interplay of the pancreas with various other organs and tissues that maintain glucose homeostasis. Furthermore, anti-diabetic drugs and their impact on signaling pathways underlying the network will be discussed.
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Affiliation(s)
- Pia V Röder
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore. E-mail: or
| | - Bingbing Wu
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
| | - Yixian Liu
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
| | - Weiping Han
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore. E-mail: or
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14
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Nivlet L, Herrmann J, Martin DE, Meunier A, Orvain C, Gradwohl G. Expression and functional studies of the GDNF family receptor alpha 3 in the pancreas. J Mol Endocrinol 2016; 56:77-90. [PMID: 26576643 PMCID: PMC5911917 DOI: 10.1530/jme-15-0213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2015] [Indexed: 01/11/2023]
Abstract
The generation of therapeutic β-cells from human pluripotent stem cells relies on the identification of growth factors that faithfully mimic pancreatic β-cell development in vitro. In this context, the aim of the study was to determine the expression and function of the glial cell line derived neurotrophic factor receptor alpha 3 (GFRα3) and its ligand artemin (Artn) in islet cell development and function. GFRα3 and Artn expression were characterized by in situ hybridization, immunochemistry, and qRT-PCR. We used GFRα3-deficient mice to study GFRα3 function and generated transgenic mice overexpressing Artn in the embryonic pancreas to study Artn function. We found that GFRα3 is expressed at the surface of a subset of Ngn3-positive endocrine progenitors as well as of embryonic α- and β-cells, while Artn is found in the pancreatic mesenchyme. Adult β-cells lack GFRα3 but α-cells express the receptor. GFRα3 was also found in parasympathetic and sympathetic intra-islet neurons as well as in glial cells in the embryonic and adult pancreas. The loss of GFRα3 or overexpression of Artn has no impact on Ngn3 and islet cell formation and maintenance in the embryo. Islet organization and innervation as well as glucose homeostasis is normal in GFRα3-deficient mice suggesting functional redundancy.
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Affiliation(s)
- Laure Nivlet
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Joel Herrmann
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Delia Esteban Martin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Aline Meunier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Christophe Orvain
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Gérard Gradwohl
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC)Institut National de la Santé et de la Recherche Médicale (INSERM) U964, Centre National de Recherche Scientifique (CNRS) UMR 7104, Université de Strasbourg (UdS), 1 Rue Laurent Fries, 67404 Illkirch, France
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15
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Brereton MF, Vergari E, Zhang Q, Clark A. Alpha-, Delta- and PP-cells: Are They the Architectural Cornerstones of Islet Structure and Co-ordination? J Histochem Cytochem 2015. [PMID: 26216135 DOI: 10.1369/0022155415583535] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Islet non-β-cells, the α- δ- and pancreatic polypeptide cells (PP-cells), are important components of islet architecture and intercellular communication. In α-cells, glucagon is found in electron-dense granules; granule exocytosis is calcium-dependent via P/Q-type Ca(2+)-channels, which may be clustered at designated cell membrane sites. Somatostatin-containing δ-cells are neuron-like, creating a network for intra-islet communication. Somatostatin 1-28 and 1-14 have a short bioactive half-life, suggesting inhibitory action via paracrine signaling. PP-cells are the most infrequent islet cell type. The embryologically separate ventral pancreas anlage contains PP-rich islets that are morphologically diffuse and α-cell deficient. Tissue samples taken from the head region are unlikely to be representative of the whole pancreas. PP has anorexic effects on gastro-intestinal function and alters insulin and glucagon secretion. Islet architecture is disrupted in rodent diabetic models, diabetic primates and human Type 1 and Type 2 diabetes, with an increased α-cell population and relocation of non-β-cells to central areas of the islet. In diabetes, the transdifferentiation of non-β-cells, with changes in hormone content, suggests plasticity of islet cells but cellular function may be compromised. Understanding how diabetes-related disordered islet structure influences intra-islet cellular communication could clarify how non-β-cells contribute to the control of islet function.
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Affiliation(s)
- Melissa F Brereton
- Department of Physiology, Anatomy and Genetics, University of Oxford, United Kingdom. (MFB)
| | - Elisa Vergari
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, United Kingdom. (EV, QZ, AC)
| | - Quan Zhang
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, United Kingdom. (EV, QZ, AC)
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, United Kingdom. (EV, QZ, AC)
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16
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Sandoval DA, D'Alessio DA. Physiology of proglucagon peptides: role of glucagon and GLP-1 in health and disease. Physiol Rev 2015; 95:513-48. [PMID: 25834231 DOI: 10.1152/physrev.00013.2014] [Citation(s) in RCA: 307] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The preproglucagon gene (Gcg) is expressed by specific enteroendocrine cells (L-cells) of the intestinal mucosa, pancreatic islet α-cells, and a discrete set of neurons within the nucleus of the solitary tract. Gcg encodes multiple peptides including glucagon, glucagon-like peptide-1, glucagon-like peptide-2, oxyntomodulin, and glicentin. Of these, glucagon and GLP-1 have received the most attention because of important roles in glucose metabolism, involvement in diabetes and other disorders, and application to therapeutics. The generally accepted model is that GLP-1 improves glucose homeostasis indirectly via stimulation of nutrient-induced insulin release and by reducing glucagon secretion. Yet the body of literature surrounding GLP-1 physiology reveals an incompletely understood and complex system that includes peripheral and central GLP-1 actions to regulate energy and glucose homeostasis. On the other hand, glucagon is established principally as a counterregulatory hormone, increasing in response to physiological challenges that threaten adequate blood glucose levels and driving glucose production to restore euglycemia. However, there also exists a potential role for glucagon in regulating energy expenditure that has recently been suggested in pharmacological studies. It is also becoming apparent that there is cross-talk between the proglucagon derived-peptides, e.g., GLP-1 inhibits glucagon secretion, and some additive or synergistic pharmacological interaction between GLP-1 and glucagon, e.g., dual glucagon/GLP-1 agonists cause more weight loss than single agonists. In this review, we discuss the physiological functions of both glucagon and GLP-1 by comparing and contrasting how these peptides function, variably in concert and opposition, to regulate glucose and energy homeostasis.
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Affiliation(s)
- Darleen A Sandoval
- Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - David A D'Alessio
- Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, Cincinnati, Ohio
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17
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18
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Vogt MC, Paeger L, Hess S, Steculorum SM, Awazawa M, Hampel B, Neupert S, Nicholls HT, Mauer J, Hausen AC, Predel R, Kloppenburg P, Horvath TL, Brüning JC. Neonatal insulin action impairs hypothalamic neurocircuit formation in response to maternal high-fat feeding. Cell 2014; 156:495-509. [PMID: 24462248 DOI: 10.1016/j.cell.2014.01.008] [Citation(s) in RCA: 258] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 12/04/2013] [Accepted: 01/06/2014] [Indexed: 11/17/2022]
Abstract
Maternal metabolic homeostasis exerts long-term effects on the offspring's health outcomes. Here, we demonstrate that maternal high-fat diet (HFD) feeding during lactation predisposes the offspring for obesity and impaired glucose homeostasis in mice, which is associated with an impairment of the hypothalamic melanocortin circuitry. Whereas the number and neuropeptide expression of anorexigenic proopiomelanocortin (POMC) and orexigenic agouti-related peptide (AgRP) neurons, electrophysiological properties of POMC neurons, and posttranslational processing of POMC remain unaffected in response to maternal HFD feeding during lactation, the formation of POMC and AgRP projections to hypothalamic target sites is severely impaired. Abrogating insulin action in POMC neurons of the offspring prevents altered POMC projections to the preautonomic paraventricular nucleus of the hypothalamus (PVH), pancreatic parasympathetic innervation, and impaired glucose-stimulated insulin secretion in response to maternal overnutrition. These experiments reveal a critical timing, when altered maternal metabolism disrupts metabolic homeostasis in the offspring via impairing neuronal projections, and show that abnormal insulin signaling contributes to this effect.
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Affiliation(s)
- Merly C Vogt
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Lars Paeger
- Biocenter, Institute for Zoology, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Simon Hess
- Biocenter, Institute for Zoology, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Sophie M Steculorum
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Motoharu Awazawa
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Brigitte Hampel
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Susanne Neupert
- Biocenter, Institute for Zoology, University of Cologne, 50674 Cologne, Germany
| | - Hayley T Nicholls
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Jan Mauer
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - A Christine Hausen
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Reinhard Predel
- Biocenter, Institute for Zoology, University of Cologne, 50674 Cologne, Germany
| | - Peter Kloppenburg
- Biocenter, Institute for Zoology, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Department of Obstetrics/Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT 06510, USA.
| | - Jens C Brüning
- Max Planck Institute for Neurological Research, 50931 Cologne, Germany; Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Cologne, 50674 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50674 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, 50924 Cologne, Germany.
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19
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Lombaert IMA, Abrams SR, Li L, Eswarakumar VP, Sethi AJ, Witt RL, Hoffman MP. Combined KIT and FGFR2b signaling regulates epithelial progenitor expansion during organogenesis. Stem Cell Reports 2013; 1:604-19. [PMID: 24371813 PMCID: PMC3871401 DOI: 10.1016/j.stemcr.2013.10.013] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/30/2013] [Accepted: 10/31/2013] [Indexed: 11/14/2022] Open
Abstract
Organ formation and regeneration require epithelial progenitor expansion to engineer, maintain, and repair the branched tissue architecture. Identifying the mechanisms that control progenitor expansion will inform therapeutic organ (re)generation. Here, we discover that combined KIT and fibroblast growth factor receptor 2b (FGFR2b) signaling specifically increases distal progenitor expansion during salivary gland organogenesis. FGFR2b signaling upregulates the epithelial KIT pathway so that combined KIT/FGFR2b signaling, via separate AKT and mitogen-activated protein kinase (MAPK) pathways, amplifies FGFR2b-dependent transcription. Combined KIT/FGFR2b signaling selectively expands the number of KIT+K14+SOX10+ distal progenitors, and a genetic loss of KIT signaling depletes the distal progenitors but also unexpectedly depletes the K5+ proximal progenitors. This occurs because the distal progenitors produce neurotrophic factors that support gland innervation, which maintains the proximal progenitors. Furthermore, a rare population of KIT+FGFR2b+ cells is present in adult glands, in which KIT signaling also regulates epithelial-neuronal communication during homeostasis. Our findings provide a framework to direct regeneration of branched epithelial organs. Combined KIT and FGFR2b signaling amplifies FGFR2b-dependent transcription KIT/FGFR2b signaling during organogenesis expands distal KIT+ epithelial progenitors Distal progenitors communicate with proximal progenitors via the neuronal niche KIT+ progenitors maintain epithelial-neuronal communication during adult homeostasis
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Affiliation(s)
- Isabelle M A Lombaert
- Matrix and Morphogenesis Section, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shaun R Abrams
- Matrix and Morphogenesis Section, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Li Li
- Department of Orthopedics & Rehabilitation, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Veraragavan P Eswarakumar
- Department of Orthopedics & Rehabilitation, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Aditya J Sethi
- Developmental Mechanisms Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert L Witt
- Head & Neck Multidisciplinary Clinic, Helen F. Graham Cancer Center of Christiana Care, Newark, DE 19713, USA
| | - Matthew P Hoffman
- Matrix and Morphogenesis Section, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
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20
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Wang K, Demir IE, D'Haese JG, Tieftrunk E, Kujundzic K, Schorn S, Xing B, Kehl T, Friess H, Ceyhan GO. The neurotrophic factor neurturin contributes toward an aggressive cancer cell phenotype, neuropathic pain and neuronal plasticity in pancreatic cancer. Carcinogenesis 2013; 35:103-13. [PMID: 24067900 DOI: 10.1093/carcin/bgt312] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED Neurotrophic factors possess an emerging role in the pathophysiology of several gastrointestinal disorders, regulating innervation, pain sensation and disease-associated neuroplasticity. Here, we aimed at characterizing the role of the neurotrophic factor neurturin (NRTN) and its receptor glial-cell-line-derived neurotrophic factor receptor alpha-2 (GFRα-2) in pancreatic cancer (PCa) and pancreatic neuropathy. For this purpose, NRTN and GFRα-2 were studied in normal human pancreas and PCa tissues via immunohistochemistry, quantitative reverse transcription-polymerase chain reaction, immunoblotting and correlated to abdominal pain. The impact of NRTN/GFRα-2 on PCa cell (PCC) biology was investigated via exposure to hypoxia, 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide viability and matrigel invasion assays in native and specific small interfering RNA-silenced PCCs. To assess the influence of NRTN on pancreatic neuroplasticity and neural invasion (NI), its impact was explored via an in vitro 'neuroplasticity assay' and a 3D neural migration assay. NRTN and GFRα-2 demonstrated a site-specific upregulation in PCa, predominantly in nerves, PCCs and extracellular matrix. Patients with severe pain demonstrated higher intraneural GFRα-2 immunoreactivity than patients with no pain. PCa tissue and PCCs contained increased amounts of NRTN, which was suppressed under hypoxia. NRTN promoted PCC invasiveness, and silencing of NRTN limited both PCC proliferation and invasion. Depletion of NRTN from PCa tissue extracts and PCC supernatants decreased axonal sprouting in neuronal cultures but did not influence glial density. Silencing of NRTN in PCCs boosted NI. We conclude that increased NRTN/GFRα-2 in PCa seems to promote an aggressive PCC phenotype and neuroplasticity in PCa. Accelerated NI following NRTN suppression constitutes a novel explanation for the attraction of PCC to nerves in the hypoxic PCa tumor microenvironment. SUMMARY PCa is characterized by intrapancreatic neuroplasticity and NI. Here, we show that PCC produce the neurotrophic factor NRTN, which reinforces their biological properties, triggers neuroplastic alterations, NI and influences pain sensation via the GFRα-2 receptor.
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Affiliation(s)
- Kun Wang
- Department of Surgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, Munich D-81675, Germany and
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Muñoz-Bravo JL, Hidalgo-Figueroa M, Pascual A, López-Barneo J, Leal-Cerro A, Cano DA. GDNF is required for neural colonization of the pancreas. Development 2013; 140:3669-79. [PMID: 23903190 DOI: 10.1242/dev.091256] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The mammalian pancreas is densely innervated by both the sympathetic and parasympathetic nervous systems, which control exocrine and endocrine secretion. During embryonic development, neural crest cells migrating in a rostrocaudal direction populate the gut, giving rise to neural progenitor cells. Recent studies in mice have shown that neural crest cells enter the pancreatic epithelium at E11.5. However, the cues that guide the migration of neural progenitors into the pancreas are poorly defined. In this study we identify glial cell line-derived neurotrophic factor (GDNF) as a key player in this process. GDNF displays a dynamic expression pattern during embryonic development that parallels the chronology of migration and differentiation of neural crest derivatives in the pancreas. Conditional inactivation of Gdnf in the pancreatic epithelium results in a dramatic loss of neuronal and glial cells and in reduced parasympathetic innervation in the pancreas. Importantly, the innervation of other regions of the gut remains unaffected. Analysis of Gdnf mutant mouse embryos and ex vivo experiments indicate that GDNF produced in the pancreas acts as a neurotrophic factor for gut-resident neural progenitor cells. Our data further show that exogenous GDNF promotes the proliferation of pancreatic progenitor cells in organ culture. In summary, our results point to GDNF as crucial for the development of the intrinsic innervation of the pancreas.
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Affiliation(s)
- José Luis Muñoz-Bravo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, Seville, Spain
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22
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Bonal CB, Baronnier DE, Pot C, Benkhoucha M, Schwab ME, Lalive PH, Herrera PL. Nogo-A downregulation improves insulin secretion in mice. Diabetes 2013; 62:1443-52. [PMID: 23274909 PMCID: PMC3636604 DOI: 10.2337/db12-0949] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes (T2D) is characterized by β-cell dysfunction and the subsequent depletion of insulin production, usually in a context of increased peripheral insulin resistance. T2D patients are routinely treated with oral antidiabetic agents such as sulfonylureas or dipeptidyl peptidase-4 antagonists, which promote glucose- and incretin-dependent insulin secretion, respectively. Interestingly, insulin secretion may also be induced by neural stimulation. Here we report the expression of Nogo-A in β-cells. Nogo-A is a membrane protein that inhibits neurite outgrowth and cell migration in the central nervous system. We observed that Nogo-A-deficient mice display improved insulin secretion and glucose clearance. This was associated with a stronger parasympathetic input and higher sensitivity of β-cells to the cholinergic analog carbachol. Insulin secretion was also improved in diabetic db/db mice treated with neutralizing antibody against Nogo-A. Together, these findings suggest that promoting the vagal stimulation of insulin secretion through the selective inhibition of Nogo-A could be a novel therapeutic approach in T2D.
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Affiliation(s)
- Claire B. Bonal
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Delphine E. Baronnier
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Caroline Pot
- Division of Neurology, Department of Neurosciences, Geneva University Hospital, Geneva, Switzerland
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Mahdia Benkhoucha
- Division of Neurology, Department of Neurosciences, Geneva University Hospital, Geneva, Switzerland
| | - Martin E. Schwab
- Brain Research Institute, University of Zurich, Zurich, Switzerland
- Department of Biology, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Patrice H. Lalive
- Division of Neurology, Department of Neurosciences, Geneva University Hospital, Geneva, Switzerland
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
- Division of Laboratory Medicine, Department of Genetic and Laboratory Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Pedro L. Herrera
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Corresponding author: Pedro L. Herrera,
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Hypothalamic ventromedial COUP-TFII protects against hypoglycemia-associated autonomic failure. Proc Natl Acad Sci U S A 2013; 110:4333-8. [PMID: 23440210 DOI: 10.1073/pnas.1219262110] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nuclear receptor Chicken Ovalbumin Upstream Promoter-Transcription Factor II (COUP-TFII) is an important coordinator of glucose homeostasis through its function in different organs such as the endocrine pancreas, adipose tissue, skeletal muscle, and liver. Recently we have demonstrated that COUP-TFII expression in the hypothalamus is restricted to a subpopulation of neurons expressing the steroidogenic factor 1 transcription factor, known to play a crucial role in glucose homeostasis. To understand the functional significance of COUP-TFII expression in the steroidogenic factor 1 neurons, we generated hypothalamic ventromedial nucleus-specific COUP-TFII KO mice using the cyclization recombination/locus of X-overP1 technology. The heterozygous mutant mice display insulin hypersensitivity and a leaner phenotype associated with increased energy expenditure and similar food intake. These mutant mice also present a defective counterregulation to hypoglycemia with altered glucagon secretion. Moreover, the mutant mice are more likely to develop hypoglycemia-associated autonomic failure in response to recurrent hypoglycemic or glucopenic events. Therefore, COUP-TFII expression levels in the ventromedial nucleus are keys in the ability to resist the onset of hypoglycemia-associated autonomic failure.
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Kupari J, Rossi J, Herzig KH, Airaksinen MS. Lack of cholinergic innervation in gastric mucosa does not affect gastrin secretion or basal acid output in neurturin receptor GFRα2 deficient mice. J Physiol 2013; 591:2175-88. [PMID: 23339174 DOI: 10.1113/jphysiol.2012.246801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Efferent signals from the vagus nerve are thought to mediate both basal and meal-induced gastric acid secretion, and provide trophic support of the mucosa. However, the underlying mechanisms are incompletely understood. Neurturin, signalling via glial cell line-derived neurotrophic factor (GDNF)-family receptor α2 (GFRα2), is essential for parasympathetic innervation of many target tissues but its role in gastric innervation is unknown. Here we show that most nerve fibres in wild-type mouse gastric mucosa, including all positive for gastrin-releasing peptide, are cholinergic. GFRα2-deficient (KO) mice lacked virtually all cholinergic nerve fibres and associated glial cells in the gastric (oxyntic and pyloric) mucosa but not in the smooth muscle, consistent with the selective expression of neurturin mRNA in the gastric mucosa. 2-Deoxyglucose and hexamethonium failed to affect acid secretion in the GFRα2-KO mice indicating the lack of functional innervation in gastric mucosa. Interestingly, basal and maximal histamine-induced acid secretion did not differ between wild-type and GFRα2-KO mice. Moreover, circulating gastrin levels in both fasted and fed animals, thickness of gastric mucosa, and density of parietal and different endocrine cells were similar. Carbachol-stimulated acid secretion was higher in GFRα2-KO mice, while atropine reduced basal secretion similarly in both genotypes. We conclude that cholinergic innervation of gastric mucosa depends on neurturin-GFRα2 signalling but is dispensable for gastrin secretion and for basal and maximal acid output. Basal acid secretion in the KO mice appears to be, at least partly, facilitated by constitutive activity of muscarinic receptors.
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Affiliation(s)
- Jussi Kupari
- Institute of Biomedicine, Anatomy, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
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25
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Marino JS, Xu Y, Hill JW. Central insulin and leptin-mediated autonomic control of glucose homeostasis. Trends Endocrinol Metab 2011; 22:275-85. [PMID: 21489811 PMCID: PMC5154334 DOI: 10.1016/j.tem.2011.03.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 02/25/2011] [Accepted: 03/05/2011] [Indexed: 12/17/2022]
Abstract
Largely as a result of rising obesity rates, the incidence of type 2 diabetes is escalating rapidly. Type 2 diabetes results from multi-organ dysfunctional glucose metabolism. Recent publications have highlighted hypothalamic insulin- and adipokine-sensing as a major determinant of peripheral glucose and insulin responsiveness. The preponderance of evidence indicates that the brain is the master regulator of glucose homeostasis, and that hypothalamic insulin and leptin signaling in particular play a crucial role in the development of insulin resistance. This review discusses the neuronal crosstalk between the hypothalamus, autonomic nervous system, and tissues associated with the pathogenesis of type 2 diabetes, and how hypothalamic insulin and leptin signaling are integral to maintaining normal glucose homeostasis.
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Affiliation(s)
- Joseph S Marino
- Center for Diabetes and Endocrine Research, College of Medicine, The University of Toledo, Toledo, OH 43614, USA
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Schmutzler BS, Roy S, Pittman SK, Meadows RM, Hingtgen CM. Ret-dependent and Ret-independent mechanisms of Gfl-induced sensitization. Mol Pain 2011; 7:22. [PMID: 21450093 PMCID: PMC3078874 DOI: 10.1186/1744-8069-7-22] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 03/30/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The GDNF family ligands (GFLs) are regulators of neurogenic inflammation and pain. We have previously shown that GFLs increase the release of the sensory neuron neuropeptide, calcitonin gene-related peptide (CGRP) from isolated mouse DRG. RESULTS Inhibitors of the mitogen-activated protein kinase (MAPK) pathway abolished the enhancement of CGRP release by GDNF. Neurturin-induced enhancement in the stimulated release of CGRP, used as an indication of sensory neuronal sensitization, was abolished by inhibition of the phosphatidylinositol-3 kinase (PI-3K) pathway. Reduction in Ret expression abolished the GDNF-induced sensitization, but did not fully inhibit the increase in stimulus-evoked release of CGRP caused by neurturin or artemin, indicating the presence of Ret-independent GFL-induced signaling in sensory neurons. Integrin β-1 and NCAM are involved in a component of Ret-independent GFL signaling in sensory neurons. CONCLUSIONS These data demonstrate the distinct and variable Ret-dependent and Ret-independent signaling mechanisms by which GFLs induce sensitization of sensory neurons. Additionally, there is a clear disconnect between intracellular signaling pathway activation and changes in sensory neuronal function.
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Affiliation(s)
- Brian S Schmutzler
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, 46202, USA.
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Abstract
This short review outlines the physiology of glucagon in vivo, with an emphasis on its neural control, the author's area of interest. Glucagon is secreted from alpha cells, which are a minority of the pancreatic islet. Anatomically, they are down stream from the majority islet beta cells. Beta-cell secretory products restrain glucagon secretion. Activation of the autonomic nerves, which innervate the islet, increases glucagon secretion. Glucagon is secreted into the portal vein and thus has its major physiologic action at the liver to break down glycogen. Glucagon thereby maintains hepatic glucose production during fasting and increases hepatic glucose production during stress, including the clinically important stress of hypoglycemia. Three different mechanisms proposed to stimulate glucagon secreted during hypoglycemia are discussed: (1) a stimulatory effect of low glucose directly on the alpha cell, (2) withdrawal of an inhibitory effect of adjacent beta cells, and (3) a stimulatory effect of autonomic activation. In type 1 diabetes (T1DM), increased glucagon secretion contributes to the elevated ketones and acidosis present in diabetic ketoacidosis (DKA). It also contributes to the hyperglycemia seen with or without DKA. The glucagon response to insulin-induced hypoglycemia is impaired soon after the development of T1DM. The mediators of this impairment include loss of beta cells and loss of sympathetic nerves from the autoimmune diabetic islet.
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Developmental determinants of the independence and complexity of the enteric nervous system. Trends Neurosci 2010; 33:446-56. [DOI: 10.1016/j.tins.2010.06.002] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 06/08/2010] [Accepted: 06/14/2010] [Indexed: 02/06/2023]
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Callahan T, Young HM, Anderson RB, Enomoto H, Anderson CR. Development of satellite glia in mouse sympathetic ganglia: GDNF and GFR alpha 1 are not essential. Glia 2009; 56:1428-37. [PMID: 18551627 DOI: 10.1002/glia.20709] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The phenotypic development of satellite cells in mouse sympathetic ganglia was examined by localizing the transcription factors, Sox10 and Phox2b, the neuronal marker, tyrosine hydroxylase (TH), and brain-derived fatty acid binding protein (B-FABP), which identifies glial precursors and mature glia. In E10.5 mice, most cells in the sympathetic chain expressed both Sox10 and Phox2b, with a minority of cells expressing Sox10 only or Phox2b only. In E11.5 mice, the majority of cells expressed Sox10 only or Phox2b only. B-FABP was colocalized with Sox10 in satellite glial precursors, which were located on the periphery of the ganglion. There was no overlap between B-FABP and Phox2b or B-FABP and TH. During subsequent development, the number of B-FABP+ cells increased and they became more common deep within the ganglion. In E12.5 and E18.5 mice, there was no overlap between Sox10 and Phox2b, and 98% of Sox10 cells were also B-FABP+. Satellite glial precursors in E11.5-E15.5 mice also expressed the GDNF-binding molecule, GFRalpha1. B-FABP immunoreactive cells did not express Ret or NCAM, two potential signaling molecules for GDNF/GFRalpha1. In E12.5 and E18.5 mice lacking GFRalpha1 or GDNF, the development of B-FABP immunoreactive satellite cells was normal, and hence neither GDNF or GFRalpha1 are essential for the development of satellite glia in sympathetic ganglia.
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Affiliation(s)
- Thomas Callahan
- Department of Anatomy and Cell Biology, University of Melbourne, Victoria 3010, Australia
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30
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Oikari S, Ahtialansaari T, Huotari A, Kiehne K, Fölsch UR, Wolffram S, Jänne J, Alhonen L, Herzig KH. Effect of medium- and long-chain fatty acid diets on PPAR and SREBP-1 expression and glucose homeostasis in ACBP-overexpressing transgenic rats. Acta Physiol (Oxf) 2008; 194:57-65. [PMID: 18394026 DOI: 10.1111/j.1748-1716.2008.01860.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM Acyl-CoAs are important intermediates and regulators of lipid metabolism. Binding proteins like acyl-CoA binding protein (ACBP) can influence their regulatory functions. ACBP has also been shown to exert direct effects on gene regulation in vitro. As the physiological relevance of ACBP in the regulation of lipid metabolism under high fat diets is unclear, we investigated the influence of such diets on the metabolic responses in ACBP-overexpressing rats. METHODS A transgenic rat line overexpressing the ACBP gene was used to study the effects of 4 weeks of feeding with medium- (MC) or long-chain (LC) fatty acid-containing diets. Glucose tolerance tests were performed. Expression of transcription factors was measured by quantitative RT-PCR and protein levels of AMP-activated protein kinase were determined by western blotting. RESULTS Transgenic animals fed the MC diet had an improved glucose tolerance and lower serum insulin levels compared with controls. Their liver PPARgamma (by 43%) and SREBP-1 (by 35%) mRNA levels were found to be decreased, while adipose tissue PPARgamma expression was increased by 31%. Tg animals fed the LC diet did not exhibit changes in glucose or insulin levels but exhibited increased mRNA levels of liver PPARs and SREBP-1 (1.5-3.5 times) and decreased protein levels of AMPKalpha (by 48%). CONCLUSIONS Our results demonstrate that ACBP overexpression affects metabolic responses to diets with distinct difference in their fatty acid chain lengths. The molecular regulatory mechanism behind these effects seems to be an ACBP-induced tissue-specific regulation of expression of PPARs and SREBP.
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Affiliation(s)
- S Oikari
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, Kuopio, Finland
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Effect of protein, fat, carbohydrate and fibre on gastrointestinal peptide release in humans. ACTA ACUST UNITED AC 2008; 149:70-8. [DOI: 10.1016/j.regpep.2007.10.008] [Citation(s) in RCA: 184] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2007] [Accepted: 10/22/2007] [Indexed: 02/07/2023]
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Burcelin R, Knauf C, Cani P. Pancreatic α-cell dysfunction in diabetes. DIABETES & METABOLISM 2008; 34 Suppl 2:S49-55. [DOI: 10.1016/s1262-3636(08)73395-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Burris RE, Hebrok M. Pancreatic innervation in mouse development and beta-cell regeneration. Neuroscience 2007; 150:592-602. [PMID: 18006238 DOI: 10.1016/j.neuroscience.2007.09.079] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Revised: 08/17/2007] [Accepted: 10/23/2007] [Indexed: 01/08/2023]
Abstract
Pancreatic innervation is being viewed with increasing interest with respect to pancreatic disease. At the same time, relatively little is currently known about innervation dynamics during development and disease. The present study employs confocal microscopy to analyze the growth and development of sympathetic and sensory neurons and astroglia during pancreatic organogenesis and maturation. Our research reveals that islet innervation is closely linked to the process of islet maturation-neural cell bodies undergo intrapancreatic migration/shuffling in tandem with endocrine cells, and close neuro-endocrine contacts are established quite early in pancreatic development. In addition, we have assayed the effects of large-scale beta-cell loss and repopulation on the maintenance of islet innervation with respect to particular neuron types. We demonstrate that depletion of the beta-cell population in the rat insulin promoter (RIP)-cmyc(ER) mouse line has cell-type-specific effects on postganglionic sympathetic neurons and pancreatic astroglia. This study contributes to a greater understanding of how cooperating physiological systems develop together and coordinate their functions, and also helps to elucidate how permutation of one organ system through stress or disease can specifically affect parallel systems in an organism.
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Affiliation(s)
- R E Burris
- University of California, San Francisco, Diabetes Center, San Francisco, CA 94143-0540, USA
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Tong Q, Ye C, McCrimmon RJ, Dhillon H, Choi B, Kramer MD, Yu J, Yang Z, Christiansen LM, Lee CE, Choi CS, Zigman JM, Shulman GI, Sherwin RS, Elmquist JK, Lowell BB. Synaptic glutamate release by ventromedial hypothalamic neurons is part of the neurocircuitry that prevents hypoglycemia. Cell Metab 2007; 5:383-93. [PMID: 17488640 PMCID: PMC1934926 DOI: 10.1016/j.cmet.2007.04.001] [Citation(s) in RCA: 316] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 03/26/2007] [Accepted: 04/11/2007] [Indexed: 10/23/2022]
Abstract
The importance of neuropeptides in the hypothalamus has been experimentally established. Due to difficulties in assessing function in vivo, the roles of the fast-acting neurotransmitters glutamate and GABA are largely unknown. Synaptic vesicular transporters (VGLUTs for glutamate and VGAT for GABA) are required for vesicular uptake and, consequently, synaptic release of neurotransmitters. Ventromedial hypothalamic (VMH) neurons are predominantly glutamatergic and express VGLUT2. To evaluate the role of glutamate release from VMH neurons, we generated mice lacking VGLUT2 selectively in SF1 neurons (a major subset of VMH neurons). These mice have hypoglycemia during fasting secondary to impaired fasting-induced increases in the glucose-raising pancreatic hormone glucagon and impaired induction in liver of mRNAs encoding PGC-1alpha and the gluconeogenic enzymes PEPCK and G6Pase. Similarly, these mice have defective counterregulatory responses to insulin-induced hypoglycemia and 2-deoxyglucose (an antimetabolite). Thus, glutamate release from VMH neurons is an important component of the neurocircuitry that functions to prevent hypoglycemia.
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Affiliation(s)
- Qingchun Tong
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - ChianPing Ye
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Rory J. McCrimmon
- Department of Internal Medicine & Endocrinology, Yale University School of Medicine, New Haven, CT, 06520
| | - Harveen Dhillon
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Brian Choi
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Melissa D. Kramer
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Jia Yu
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Zongfang Yang
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Lauryn M. Christiansen
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
| | - Charlotte E. Lee
- Center for Hypothalamic Research, Departments of Internal Medicine and Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9077
| | - Cheol Soo Choi
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, 06520
| | - Jeffrey M. Zigman
- Center for Hypothalamic Research, Departments of Internal Medicine and Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9077
| | - Gerald I. Shulman
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, 06520
- Department of Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06520
- Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT, 06520
| | - Robert S. Sherwin
- Department of Internal Medicine & Endocrinology, Yale University School of Medicine, New Haven, CT, 06520
| | - Joel K. Elmquist
- Center for Hypothalamic Research, Departments of Internal Medicine and Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9077
| | - Bradford B. Lowell
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 99 Brookline Ave., Boston, MA, 02215
- * To whom correspondence should be addressed (e-mail: ) Ph: 617-667-5954; Fax: 617-667-2927
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Lähteenmäki M, Kupari J, Airaksinen MS. Increased apoptosis of parasympathetic but not enteric neurons in mice lacking GFRα2. Dev Biol 2007; 305:325-32. [PMID: 17355878 DOI: 10.1016/j.ydbio.2007.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 01/26/2007] [Accepted: 02/13/2007] [Indexed: 01/19/2023]
Abstract
Enteric neurons, unlike sympathetic and sensory neurons that require target-derived neurotrophins for survival, do not undergo classical caspase-3-mediated programmed cell death (PCD) during normal development. Whether parasympathetic neurons in the pancreas, which originate from a subpopulation of enteric nervous system (ENS) precursors, or other parasympathetic neurons undergo PCD during normal mammalian development is unknown. In GFRalpha2-deficient mice, many submandibular and intrapancreatic parasympathetic neurons are missing but whether this is due to increased neuronal death is unclear. Here we show that activated caspase-3 and PGP9.5 doubly positive neurons are present in wild-type mouse pancreas between embryonic day E15 and birth. Thus, in contrast to ENS neurons, intrapancreatic neurons undergo PCD via apoptosis during normal development. We also show that, in GFRalpha2-deficient mice, most intrapancreatic neurons are lost during this late fetal period, which coincides with a period of increased apoptosis of the neurons. Since the percentage of BrdU and Phox2b doubly positive cells in the fetal pancreas and the number of intrapancreatic neurons at E15 were similar between the genotypes, impaired precursor proliferation and migration are unlikely to contribute to the loss of intrapancreatic neurons in GFRalpha2-KO mice. Caspase-3-positive neurons were also found in GFRalpha2-deficient submandibular ganglia around birth, suggesting that parasympathetic neurons depend on limited supply of (presumably target-derived neurturin) signaling via GFRalpha2 for survival.
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Affiliation(s)
- Meri Lähteenmäki
- Neuroscience Center, Viikinkaari 4, 00014 University of Helsinki, Helsinki, Finland
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Gromada J, Franklin I, Wollheim CB. Alpha-cells of the endocrine pancreas: 35 years of research but the enigma remains. Endocr Rev 2007; 28:84-116. [PMID: 17261637 DOI: 10.1210/er.2006-0007] [Citation(s) in RCA: 424] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Glucagon, a hormone secreted from the alpha-cells of the endocrine pancreas, is critical for blood glucose homeostasis. It is the major counterpart to insulin and is released during hypoglycemia to induce hepatic glucose output. The control of glucagon secretion is multifactorial and involves direct effects of nutrients on alpha-cell stimulus-secretion coupling as well as paracrine regulation by insulin and zinc and other factors secreted from neighboring beta- and delta-cells within the islet of Langerhans. Glucagon secretion is also regulated by circulating hormones and the autonomic nervous system. In this review, we describe the components of the alpha-cell stimulus secretion coupling and how nutrient metabolism in the alpha-cell leads to changes in glucagon secretion. The islet cell composition and organization are described in different species and serve as a basis for understanding how the numerous paracrine, hormonal, and nervous signals fine-tune glucagon secretion under different physiological conditions. We also highlight the pathophysiology of the alpha-cell and how hyperglucagonemia represents an important component of the metabolic abnormalities associated with diabetes mellitus. Therapeutic inhibition of glucagon action in patients with type 2 diabetes remains an exciting prospect.
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Affiliation(s)
- Jesper Gromada
- Novartis Institutes for BioMedical Research, 100 Technology Square, Cambridge, Massachusetts 02139, USA.
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Abstract
Diabetes is the extreme manifestation of a spectrum conditions in which the balance of insulin secretion and insulin action (or insulin resistance) has been altered. Loss of euglycemia is caused by relative insulin deficiency in the presence of insulin resistance, or by absolute insulin deficiency. There are related conditions in which an alteration of insulin resistance or beta-cell dysfunction exists, but because of compensation glucose homeostasis has not been lost. The elucidation of the causes of insulin resistance and -cell failure and the attention to the different degrees of insulin deficiency and insulin resistance allow for better diagnosis, treatment, and prevention of diabetes and its related conditions.
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Affiliation(s)
- Diego Ize-Ludlow
- Division of Endocrinology, Diabetes, and Metabolism, University of Pittsburgh School of Medicine, Children's Hospital of Pittsburgh, 3705 Fifth Avenue, 4A-400, Pittsburgh, PA 15213-2583, USA
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