1
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Gylfe E, Tengholm A. Bo Hellman, 19 June 1930-4 December 2023. Diabetologia 2024; 67:1165-1167. [PMID: 38658469 DOI: 10.1007/s00125-024-06157-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Affiliation(s)
- Erik Gylfe
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
| | - Anders Tengholm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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2
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Haris B, Saraswathi S, Hussain K. Somatostatin analogues for the treatment of hyperinsulinaemic hypoglycaemia. Ther Adv Endocrinol Metab 2020; 11:2042018820965068. [PMID: 33329885 PMCID: PMC7720331 DOI: 10.1177/2042018820965068] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/11/2020] [Indexed: 01/10/2023] Open
Abstract
Hyperinsulinaemic hypoglycaemia (HH) is a biochemical finding of low blood glucose levels due to the dysregulation of insulin secretion from pancreatic β-cells. Under normal physiological conditions, glucose metabolism is coupled to β-cell insulin secretion so that blood glucose levels are maintained within the physiological range of 3.5-5.5 mmol/L. However, in HH this coupling of glucose metabolism to insulin secretion is perturbed so that insulin secretion becomes unregulated. HH typically occurs in the neonatal, infancy and childhood periods and can be due to many different causes. Adults can also present with HH but the causes in adults tend to be different. Somatostatin (SST) is a peptide hormone that is released by the delta cells (δ-cells) in the pancreas. It binds to G protein-coupled SST receptors to regulate a variety of location-specific and selective functions such as hormone inhibition, neurotransmission and cell proliferation. SST plays a potent role in the regulation of both insulin and glucagon secretion in response to changes in glucose levels by negative feedback mechanism. The half-life of SST is only 1-3 min due to quick degradation by peptidases in plasma and tissues. Thus, a direct continuous intravenous or subcutaneous infusion is required to achieve the therapeutic effect. These limitations prompted the discovery of SST analogues such as octreotide and lanreotide, which have longer half-lives and therefore can be administered as injections. SST analogues are used to treat different forms of HH in children and adults and therapeutic effect is achieved by suppressing insulin secretion from pancreatic β-cells by complex mechanisms. These treatments are associated with several side effects, especially in the newborn period, with necrotizing enterocolitis being the most serious side effect and hence SS analogues should be used with extreme caution in this age group.
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Affiliation(s)
- Basma Haris
- Department of Paediatric Medicine, Division of Endocrinology, Sidra Medicine, Doha, Qatar
| | - Saras Saraswathi
- Department of Paediatric Medicine, Division of Endocrinology, Sidra Medicine, Doha, Qatar
| | - Khalid Hussain
- Professor of Paediatrics, Weill Cornell Medicine-Qatar, Division Chief – Endocrinology, Department of Paediatric Medicine, Division of Endocrinology, Sidra Medicine, OPC, C6-340 |PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar
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3
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Zhang Y, Yañez Guerra LA, Egertová M, Zampronio CG, Jones AM, Elphick MR. Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate. Open Biol 2020; 10:200172. [PMID: 32898470 PMCID: PMC7536072 DOI: 10.1098/rsob.200172] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Somatostatin (SS) and allatostatin-C (ASTC) are structurally and evolutionarily related neuropeptides that act as inhibitory regulators of physiological processes in mammals and insects, respectively. Here, we report the first molecular and functional characterization of SS/ASTC-type signalling in a deuterostome invertebrate—the starfish Asterias rubens (phylum Echinodermata). Two SS/ASTC-type precursors were identified in A. rubens (ArSSP1 and ArSSP2) and the structures of neuropeptides derived from these proteins (ArSS1 and ArSS2) were analysed using mass spectrometry. Pharmacological characterization of three cloned A. rubens SS/ASTC-type receptors (ArSSR1–3) revealed that ArSS2, but not ArSS1, acts as a ligand for all three receptors. Analysis of ArSS2 expression in A. rubens using mRNA in situ hybridization and immunohistochemistry revealed stained cells/fibres in the central nervous system, the digestive system (e.g. cardiac stomach) and the body wall and its appendages (e.g. tube feet). Furthermore, in vitro pharmacological tests revealed that ArSS2 causes dose-dependent relaxation of tube foot and cardiac stomach preparations, while injection of ArSS2 in vivo causes partial eversion of the cardiac stomach. Our findings provide new insights into the molecular evolution of SS/ASTC-type signalling in the animal kingdom and reveal an ancient role of SS-type neuropeptides as inhibitory regulators of muscle contractility.
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Affiliation(s)
- Ya Zhang
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | | | - Michaela Egertová
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | - Cleidiane G Zampronio
- School of Life Sciences and Proteomics Research Technology Platform, University of Warwick, Coventry CV4 7AL, UK
| | - Alexandra M Jones
- School of Life Sciences and Proteomics Research Technology Platform, University of Warwick, Coventry CV4 7AL, UK
| | - Maurice R Elphick
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
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4
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Müller TD, Finan B, Bloom SR, D'Alessio D, Drucker DJ, Flatt PR, Fritsche A, Gribble F, Grill HJ, Habener JF, Holst JJ, Langhans W, Meier JJ, Nauck MA, Perez-Tilve D, Pocai A, Reimann F, Sandoval DA, Schwartz TW, Seeley RJ, Stemmer K, Tang-Christensen M, Woods SC, DiMarchi RD, Tschöp MH. Glucagon-like peptide 1 (GLP-1). Mol Metab 2019; 30:72-130. [PMID: 31767182 PMCID: PMC6812410 DOI: 10.1016/j.molmet.2019.09.010] [Citation(s) in RCA: 875] [Impact Index Per Article: 175.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/10/2019] [Accepted: 09/22/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The glucagon-like peptide-1 (GLP-1) is a multifaceted hormone with broad pharmacological potential. Among the numerous metabolic effects of GLP-1 are the glucose-dependent stimulation of insulin secretion, decrease of gastric emptying, inhibition of food intake, increase of natriuresis and diuresis, and modulation of rodent β-cell proliferation. GLP-1 also has cardio- and neuroprotective effects, decreases inflammation and apoptosis, and has implications for learning and memory, reward behavior, and palatability. Biochemically modified for enhanced potency and sustained action, GLP-1 receptor agonists are successfully in clinical use for the treatment of type-2 diabetes, and several GLP-1-based pharmacotherapies are in clinical evaluation for the treatment of obesity. SCOPE OF REVIEW In this review, we provide a detailed overview on the multifaceted nature of GLP-1 and its pharmacology and discuss its therapeutic implications on various diseases. MAJOR CONCLUSIONS Since its discovery, GLP-1 has emerged as a pleiotropic hormone with a myriad of metabolic functions that go well beyond its classical identification as an incretin hormone. The numerous beneficial effects of GLP-1 render this hormone an interesting candidate for the development of pharmacotherapies to treat obesity, diabetes, and neurodegenerative disorders.
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Affiliation(s)
- T D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics, Tübingen, Germany.
| | - B Finan
- Novo Nordisk Research Center Indianapolis, Indianapolis, IN, USA
| | - S R Bloom
- Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London, UK
| | - D D'Alessio
- Division of Endocrinology, Duke University Medical Center, Durham, NC, USA
| | - D J Drucker
- The Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Ontario, M5G1X5, Canada
| | - P R Flatt
- SAAD Centre for Pharmacy & Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - A Fritsche
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Department of Internal Medicine, University of Tübingen, Tübingen, Germany
| | - F Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - H J Grill
- Institute of Diabetes, Obesity and Metabolism, Department of Psychology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - J F Habener
- Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Harvard University, Boston, MA, USA
| | - J J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - W Langhans
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - J J Meier
- Diabetes Division, St Josef Hospital, Ruhr-University Bochum, Bochum, Germany
| | - M A Nauck
- Diabetes Center Bochum-Hattingen, St Josef Hospital (Ruhr-Universität Bochum), Bochum, Germany
| | - D Perez-Tilve
- Department of Internal Medicine, University of Cincinnati-College of Medicine, Cincinnati, OH, USA
| | - A Pocai
- Cardiovascular & ImmunoMetabolism, Janssen Research & Development, Welsh and McKean Roads, Spring House, PA, 19477, USA
| | - F Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - D A Sandoval
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - T W Schwartz
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, DL-2200, Copenhagen, Denmark; Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - R J Seeley
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - K Stemmer
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - M Tang-Christensen
- Obesity Research, Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - S C Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - R D DiMarchi
- Novo Nordisk Research Center Indianapolis, Indianapolis, IN, USA; Department of Chemistry, Indiana University, Bloomington, IN, USA
| | - M H Tschöp
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Division of Metabolic Diseases, Department of Medicine, Technische Universität München, Munich, Germany; Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
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5
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Abstract
The somatostatin-secreting δ-cells comprise ~5% of the cells of the pancreatic islets. The δ-cells have complex morphology and might interact with many more islet cells than suggested by their low numbers. δ-Cells contain ATP-sensitive potassium channels, which open at low levels of glucose but close when glucose is elevated. This closure initiates membrane depolarization and electrical activity and increased somatostatin secretion. Factors released by neighbouring α-cells or β-cells amplify the glucose-induced effects on somatostatin secretion from δ-cells, which act locally within the islets as paracrine or autocrine inhibitors of insulin, glucagon and somatostatin secretion. The effects of somatostatin are mediated by activation of somatostatin receptors coupled to the inhibitory G protein, which culminates in suppression of the electrical activity and exocytosis in α-cells and β-cells. Somatostatin secretion is perturbed in animal models of diabetes mellitus, which might explain the loss of appropriate hypoglycaemia-induced glucagon secretion, a defect that could be mitigated by somatostatin receptor 2 antagonists. Somatostatin antagonists or agents that suppress somatostatin secretion have been proposed as an adjunct to insulin therapy. In this Review, we summarize the cell physiology of somatostatin secretion, what might go wrong in diabetes mellitus and the therapeutic potential of agents targeting somatostatin secretion or action.
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Affiliation(s)
- Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, Churchill Hospital, University of Oxford, Oxford, UK.
- Department of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
| | - Mark O Huising
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, CA, USA
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, Davis, CA, USA
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6
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The somatostatin-secreting pancreatic δ-cell in health and disease. NATURE REVIEWS. ENDOCRINOLOGY 2018. [PMID: 29773871 DOI: 10.1038/s41574‐018‐0020‐6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The somatostatin-secreting δ-cells comprise ~5% of the cells of the pancreatic islets. The δ-cells have complex morphology and might interact with many more islet cells than suggested by their low numbers. δ-Cells contain ATP-sensitive potassium channels, which open at low levels of glucose but close when glucose is elevated. This closure initiates membrane depolarization and electrical activity and increased somatostatin secretion. Factors released by neighbouring α-cells or β-cells amplify the glucose-induced effects on somatostatin secretion from δ-cells, which act locally within the islets as paracrine or autocrine inhibitors of insulin, glucagon and somatostatin secretion. The effects of somatostatin are mediated by activation of somatostatin receptors coupled to the inhibitory G protein, which culminates in suppression of the electrical activity and exocytosis in α-cells and β-cells. Somatostatin secretion is perturbed in animal models of diabetes mellitus, which might explain the loss of appropriate hypoglycaemia-induced glucagon secretion, a defect that could be mitigated by somatostatin receptor 2 antagonists. Somatostatin antagonists or agents that suppress somatostatin secretion have been proposed as an adjunct to insulin therapy. In this Review, we summarize the cell physiology of somatostatin secretion, what might go wrong in diabetes mellitus and the therapeutic potential of agents targeting somatostatin secretion or action.
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7
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Gylfe E. Glucose control of glucagon secretion-'There's a brand-new gimmick every year'. Ups J Med Sci 2016; 121:120-32. [PMID: 27044660 PMCID: PMC4900067 DOI: 10.3109/03009734.2016.1154905] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 02/10/2016] [Accepted: 02/11/2016] [Indexed: 11/13/2022] Open
Abstract
Glucagon from the pancreatic α-cells is a major blood glucose-regulating hormone whose most important role is to prevent hypoglycaemia that can be life-threatening due to the brain's strong dependence on glucose as energy source. Lack of blood glucose-lowering insulin after malfunction or autoimmune destruction of the pancreatic β-cells is the recognized cause of diabetes, but recent evidence indicates that diabetic hyperglycaemia would not develop unless lack of insulin was accompanied by hypersecretion of glucagon. Glucagon release has therefore become an increasingly important target in diabetes management. Despite decades of research, an understanding of how glucagon secretion is regulated remains elusive, and fundamentally different mechanisms continue to be proposed. The autonomous nervous system is an important determinant of glucagon release, but it is clear that secretion is also directly regulated within the pancreatic islets. The present review focuses on pancreatic islet mechanisms involved in glucose regulation of glucagon release. It will be argued that α-cell-intrinsic processes are most important for regulation of glucagon release during recovery from hypoglycaemia and that paracrine inhibition by somatostatin from the δ-cells shapes pulsatile glucagon release in hyperglycaemia. The electrically coupled β-cells ultimately determine islet hormone pulsatility by releasing synchronizing factors that affect the α- and δ-cells.
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Affiliation(s)
- Erik Gylfe
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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8
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Burnstock G. Purinergic signalling in endocrine organs. Purinergic Signal 2014; 10:189-231. [PMID: 24265070 PMCID: PMC3944044 DOI: 10.1007/s11302-013-9396-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/24/2013] [Indexed: 01/08/2023] Open
Abstract
There is widespread involvement of purinergic signalling in endocrine biology. Pituitary cells express P1, P2X and P2Y receptor subtypes to mediate hormone release. Adenosine 5'-triphosphate (ATP) regulates insulin release in the pancreas and is involved in the secretion of thyroid hormones. ATP plays a major role in the synthesis, storage and release of catecholamines from the adrenal gland. In the ovary purinoceptors mediate gonadotrophin-induced progesterone secretion, while in the testes, both Sertoli and Leydig cells express purinoceptors that mediate secretion of oestradiol and testosterone, respectively. ATP released as a cotransmitter with noradrenaline is involved in activities of the pineal gland and in the neuroendocrine control of the thymus. In the hypothalamus, ATP and adenosine stimulate or modulate the release of luteinising hormone-releasing hormone, as well as arginine-vasopressin and oxytocin. Functionally active P2X and P2Y receptors have been identified on human placental syncytiotrophoblast cells and on neuroendocrine cells in the lung, skin, prostate and intestine. Adipocytes have been recognised recently to have endocrine function involving purinoceptors.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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9
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Schwetz TA, Ustione A, Piston DW. Neuropeptide Y and somatostatin inhibit insulin secretion through different mechanisms. Am J Physiol Endocrinol Metab 2013; 304:E211-21. [PMID: 23211512 PMCID: PMC3543566 DOI: 10.1152/ajpendo.00374.2012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pancreatic β-cells regulate glucose homeostasis by secreting insulin in response to glucose elevation and G protein-coupled receptor (GPCR) activation. Neuropeptide Y (NPY) and somatostatin (SST) attenuate insulin secretion through G(i) activation of Y(1) and SSTR(1&5) receptors, respectively. The downstream pathways altered by NPY and SST are poorly understood. Thus, we investigated these underlying mechanisms. NPY and SST increase cellular redox potential, suggesting that their inhibitory effect may not be mediated through metabolic inhibition. NPY does not affect intracellular calcium ([Ca(2+)](i)) activity upon glucose stimulation, whereas SST alters this response. G(βγ)-subunit inhibition by gallein attenuates insulin secretion but does not alter metabolism or [Ca(2+)](i). mSIRK-induced G(βγ) activation does not modulate glucose metabolism but increases [Ca(2+)](i) activity and potentiates insulin release. Cotreatment with gallein and NPY or SST reduces insulin secretion to levels similar to that of gallein alone. mSIRK and NPY cotreatment potentiates insulin secretion similarly to mSIRK alone, whereas mSIRK and SST treatment decreases insulin release. The data support a model where SST attenuates secretion through G(βγ) inhibition of Ca(2+) activity, while NPY activates a Ca(2+)-independent pathway mediated by G(α). GPCR ligands signal through multiple pathways to inhibit insulin secretion, and determining these mechanisms could lead to novel diabetic therapies.
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Affiliation(s)
- Tara A Schwetz
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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10
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Abstract
Pancreatic cells contain specialised stores for ATP. Purinergic receptors (P2 and P1) and ecto-nucleotidases are expressed in both endocrine and exocrine calls, as well as in stromal cells. The pancreas, especially the endocrine cells, were an early target for the actions of ATP. After the historical perspective of purinergic signalling in the pancreas, the focus of this review will be the physiological functions of purinergic signalling in the regulation of both endocrine and exocrine pancreas. Next, we will consider possible interaction between purinergic signalling and other regulatory systems and their relation to nutrient homeostasis and cell survival. The pancreas is an organ exhibiting several serious diseases - cystic fibrosis, pancreatitis, pancreatic cancer and diabetes - and some are associated with changes in life-style and are increasing in incidence. There is upcoming evidence for the role of purinergic signalling in the pathophysiology of the pancreas, and the new challenge is to understand how it is integrated with other pathological processes.
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Affiliation(s)
- G Burnstock
- University College Medical School, Autonomic Neuroscience Centre, Rowland Hill Street, London NW3 2PF, UK.
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11
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Kumar U. Cross-talk and modulation of signaling between somatostatin and growth factor receptors. Endocrine 2011; 40:168-80. [PMID: 21870170 DOI: 10.1007/s12020-011-9524-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 08/11/2011] [Indexed: 12/19/2022]
Abstract
The process of homo- and/or heterodimerization of G-protein coupled receptors (GPCRs) and receptor tyrosine kinase (RTK) families are crucial for implicating the fundamental properties of receptor proteins including receptor expression, trafficking, and desensitization as well as signal transduction. The members of GPCR and RTK family constitute largest cell surface receptor proteins and regulate physiological functions of cells in response to external and internal stimuli. Notably, GPCRs and RTKs play major role in regulation of several key cellular functions which are associated with several pathological conditions including cancer biology, neurodegenerative and cardiovascular diseases. The focus of this review is to highlight the recent findings on the possible cross-talk between somatostatin receptors (members of GPCR family) and growth factor receptors like epidermal growth factor receptors (members of RTK family). Furthermore, functional consequences of such an interaction in modulation of signaling pathways linked to pathological conditions specifically in cancer are discussed.
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Affiliation(s)
- Ujendra Kumar
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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12
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Patel YC, Liu J, Galanopoulou A, Papachristou DN. Production, Action, and Degradation of Somatostatin. Compr Physiol 2011. [DOI: 10.1002/cphy.cp070209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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13
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Affiliation(s)
- Ujendra Kumar
- Faculty of Pharmaceutical Sciences, Department of Pharmacology and Toxicology, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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14
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Watt HL, Kharmate G, Kumar U. Biology of somatostatin in breast cancer. Mol Cell Endocrinol 2008; 286:251-61. [PMID: 18308465 DOI: 10.1016/j.mce.2008.01.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2007] [Revised: 01/02/2008] [Accepted: 01/15/2008] [Indexed: 01/29/2023]
Abstract
The biological effects of the neuropeptide somatostatin (SST) are mediated via a family of five somatostatin receptors (SSTRs) belonging to a family of G-protein-coupled receptors (GPCRs). SSTR regulate the secretion of hormones, growth factors, neurotransmission and cell growth in receptor-specific manner. In addition, SST plays an inhibitory role in several mammary cancer models. These effects are mediated both indirectly through inhibition of hormones and growth factors which promote tumor growth as well as directly via SSTRs present on tumor cells to inhibit mitogenic signaling of growth factor receptor kinases leading to growth arrest and induction of apoptosis. Here, we present an overview on the role of SST and its analogs in breast cancer.
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Affiliation(s)
- Heather L Watt
- Department of Medicine, Royal Victoria Hospital, McGill University, Canada
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15
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Salehi A, Qader SS, Grapengiesser E, Hellman B. Pulses of somatostatin release are slightly delayed compared with insulin and antisynchronous to glucagon. ACTA ACUST UNITED AC 2007; 144:43-9. [PMID: 17628719 DOI: 10.1016/j.regpep.2007.06.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 04/11/2007] [Accepted: 06/14/2007] [Indexed: 11/19/2022]
Abstract
It was early proposed that somatostatin-producing delta-cells in pancreatic islets have local inhibitory effects on the release of insulin and glucagon. Recent observations that pulses of insulin and glucagon are antisynchronous make it important to examine the temporal characteristics of glucose-induced somatostatin release. Analysis of 30 s fractions from the perfused rat pancreas indicated that increase of glucose from 3 to 20 mmol/l results in initial suppression of somatostatin release followed by regular 4-5 min pulses. During continued exposure to 20 mmol/l glucose, the pulses of somatostatin overlapped those of insulin with a delay of 30 s. Somatostatin and glucagon pulses were coupled in antisynchronous fashion (phase shift 2.4+/-0.2 min), supporting the idea that the delta-cells have a local inhibitory effect on glucagon release. It was possible to remove the pulses of somatostatin and glucagon with maintenance of the insulin rhythmicity by addition of 1 micromol/l of the P2Y(1) receptor antagonist MRS 2179.
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Affiliation(s)
- Albert Salehi
- Department of Clinical Science, CRC (UMAS), University of Lund, SE-20502 Malmö, Sweden
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16
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Abstract
The article provides a broad assessment of the occurrence of hormetic-like biphasic dose-response relationships by over 30 peptides representing many major peptide classes. These peptide-induced biphasic dose responses were observed to occur in a extensive range of tissues, affecting an diverse range of biological endpoints. Despite diversity of peptides, models and endpoints, the quantitative features of the biphasic dose responses are remarkably similar with respect to the amplitude and width of the stimulatory response. These findings strongly suggest that hormetic-like biphasic dose responses represent a broadly generalizable biological phenomenon.
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Affiliation(s)
- Edward J Calabrese
- Department of Environmental Health Sciences, University of Massachusetts, Amherst, MA 01003, USA.
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17
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Nadal A, Quesada I, Soria B. Homologous and heterologous asynchronicity between identified alpha-, beta- and delta-cells within intact islets of Langerhans in the mouse. J Physiol 1999; 517 ( Pt 1):85-93. [PMID: 10226151 PMCID: PMC2269319 DOI: 10.1111/j.1469-7793.1999.0085z.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
1. Using laser scanning confocal microscopy to image [Ca2+]i within intact murine islets of Langerhans, we analysed the [Ca2+]i signals generated by glucose in immunocytochemically identified alpha-, beta- and delta-cells. 2. Glucagon-containing alpha-cells exhibited [Ca2+]i oscillations in the absence of glucose, which petered out when islets were exposed to high glucose concentrations. 3. Somatostatin-containing delta-cells were silent in the absence of glucose but concentrations of glucose as low as 3 mM elicited oscillations. 4. In pancreatic beta-cells, a characteristic oscillatory calcium pattern was evoked when glucose levels were raised from 3 to 11 mM and this was synchronized throughout the beta-cell population. Remarkably, [Ca2+]i oscillations in non-beta-cells were completely asynchronous, both with respect to each other and to beta-cells. 5. These results demonstrate that the islet of Langerhans behaves as a functional syncytium only in terms of beta-cells, implying a pulsatile secretion of insulin. However, the lack of a co-ordinated calcium signal in alpha- and delta-cells implies that each cell acts as an independent functional unit and the concerted activity of these units results in a smoothly graded secretion of glucagon and somatostatin. Understanding the calcium signals underlying glucagon and somatostatin secretion may be of importance in the treatment of non-insulin-dependent diabetes mellitus since both glucagon and somatostatin appear to regulate insulin release in a paracrine fashion.
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Affiliation(s)
- A Nadal
- Institute of Bioengineering and Department of Physiology, Miguel Hernández University, Campus of San Juan, Alicante 03550, Spain.
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Sciciński JJ, Barker MD, Murray PJ, Jarvie EM. The solid phase synthesis of a series of tri-substituted hydantoin ligands for the somatostatin SST5 receptor. Bioorg Med Chem Lett 1998; 8:3609-14. [PMID: 9934480 DOI: 10.1016/s0960-894x(98)00647-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A series of trisubstituted hydantoins has been prepared by a versatile solid phase route employing primary alcohols, amines and amino acids as the monomeric building blocks. Several compounds showed submicromolar affinity in binding assays at recombinant human somatostatin receptors.
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Affiliation(s)
- J J Sciciński
- Glaxo Wellcome Cambridge Chemistry Laboratory, University Chemical Laboratories, UK.
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19
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20
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Zhu LJ, Krempels K, Bardin CW, O'Carroll AM, Mezey E. The localization of messenger ribonucleic acids for somatostatin receptors 1, 2, and 3 in rat testis. Endocrinology 1998; 139:350-7. [PMID: 9421433 DOI: 10.1210/endo.139.1.5661] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Somatostatin (SRIF) exerts multiple inhibitory actions throughout the body by binding to specific SRIF receptors (sst). In recent years, five subtypes of SRIF receptors (sst1-5) have been cloned. In this study, 35S-labeled complementary RNA probes were used for in situ hybridization to localize the sst1-5 messenger RNAs (mRNAs) in the rat testis and examine the changes in their distribution during the cycle of the seminiferous epithelium. We found that sst 1-3 mRNAs were visualized in rat testes and were mainly localized within the seminiferous tubules. The signal for sst3 mRNA was also found in interstitial cells. sst4 and 5 mRNAs were not detected in rat testes with the method used in this study. In Sertoli cells, the most intense labeling for sst1 and 3 mRNAs was in stages IV-VII of the cycle of the seminiferous epithelium, which coincided with the lowest labeling intensity for sst2. In germ cells, sst1-3 mRNAs showed similar patterns of distribution. In these cells, sst1-3 mRNA was not observed at the early steps of spermatogenesis. Positive signals for sst1-3 mRNAs were first apparent in the pachytene spermatocytes at stage VII and last until stage XII and in the diplotene spermatocyte at stage XIII. Positive signals for sst1-3 were also detected in round spermatids at stages I-VIII. Labeling of spermatids dramatically decreased at stage IX, when these cells began their elongating changes. The presence of three sst in testis suggests that SRIF may play an essential role in testicular function.
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Affiliation(s)
- L J Zhu
- The Population Council, Center for Biomedical Research, New York, New York 10021, USA.
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21
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Liapakis G, Fitzpatrick D, Hoeger C, Rivier J, Vandlen R, Reisine T. Identification of ligand binding determinants in the somatostatin receptor subtypes 1 and 2. J Biol Chem 1996; 271:20331-9. [PMID: 8702767 DOI: 10.1074/jbc.271.34.20331] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The somatostatin (SRIF) receptors (SSTRs) 1 and 2 bind SRIF and SRIF 28 with high affinity, although a number of synthetic hexapeptide and octapeptide analogs of SRIF bind selectively to SSTR2. Extracellular loop three and its adjoining trans-membrane-spanning regions contain elements essential for the binding of such analogs to murine SSTR2. In particular, a stretch of amino acids from residues 294-297 (FDFV) in murine SSTR2 in trans-membrane domain seven can determine affinity for the SSTR2-selective analogs. Within this region, Phe294 has previously been predicted to be essential for the binding of octapeptides (Kaupmann, K., Bruns, C., Raulf, F., Weber, H., Mattes, H., and Lubbert, H. (1995) EMBO J. 14, 727-735) based on the observation that SSTR1 can bind the octapeptide SMS-201-995 with reasonable affinity after a Ser-to-Phe conversion in the analogous region of this receptor (SSTR1S305F). We find that SSTR1S305F has low affinity for a number of SSTR2-selective hexapeptides, suggesting that these analogs have different binding requirements than SMS-201-995. A correlation is seen between the ability of SSTR1S305F to bind hexapeptide analogs and the presence of a phenylalanine, but not tyrosine, at position two in these small cyclic molecules. Thus, a single hydroxyl group in hexapeptides can play a critical role in determining receptor binding to these receptor mutants. We also find that the second extracellular loop of SSTR1 is important for the selectivity of certain SRIF agonists for binding to SSTR1. Taken together, our data indicate that there are multiple elements in the somatostatin receptors that can determine the binding affinity and selectivity of peptide analogs.
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Affiliation(s)
- G Liapakis
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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23
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Tallent M, Liapakis G, O'Carroll AM, Lolait SJ, Dichter M, Reisine T. Somatostatin receptor subtypes SSTR2 and SSTR5 couple negatively to an L-type Ca2+ current in the pituitary cell line AtT-20. Neuroscience 1996; 71:1073-81. [PMID: 8684611 DOI: 10.1016/0306-4522(95)00510-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The somatostatin receptor subtypes SSTR2 and SSTR5 mediate distinct endocrine and exocrine functions of somatostatin and may also be involved in mediating the neuromodulatory actions of somatostatin in the brain. To investigate whether these receptors couple to voltage-sensitive Ca2+ channels, SSTR2 and SSTR5 selective agonists were tested for their effects on AtT-20 cells using whole cell patch clamp techniques. The SSTR2 selective agonist MK 678 inhibited Ca2+ currents in AtT-20 cells. The effects of MK 678 were reversible and blocked by pertussis toxin pretreatment, suggesting that SSTR2 couples to the L-type Ca2+ channels via G proteins. Other SSTR2-selective agonists, including BIM 23027 and NC8-12, were able to inhibit the Ca2+ currents in these cells. The SSTR5 selective agonist BIM 23052 also inhibited the Ca2+ currents in these cells and this effect was reversible and blocked by pertussis toxin treatment. The ability of SSTR5 to mediate inhibition of the Ca2+ current was greatly attenuated by pretreatment with the SSTR5-selective agonist BIM 23052, whereas SSTR2-mediated inhibition of the Ca2+ current was not altered by pretreatment with the SSTR2-selective agonist MK 678. Thus, the SSTR2 and SSTR5 couplings to the Ca2+ current are differentially regulated. The peptide L362,855, which we previously have shown to have high affinity for the cloned SSTR5, had minimal effects on Ca2+ currents in AtT-20 cells at concentrations up to 100 nM and did not alter the ability of MK 678 to inhibit Ca2+ currents. However, it completely antagonized the effects of the SSTR5-selective agonist BIM 23052 on the Ca2+ currents. L362,855 is an antagonist/partial agonist at SSTR5 since it can reduce Ca2+ currents in these cells at concentrations above 100 nM. L362,855 is also an antagonist/partial agonist at the cloned rat SSTR5 expressed in CHO cells since it is able to block the inhibition of cAMP accumulation induced by somatostatin at concentrations below 100 nM but at higher concentrations can inhibit cAMP formation itself. Structural analysis of L362,855 reveals that only a single hydroxyl group at residue seven in the peptide is needed to convert the compound from an antagonist/partial agonist to a full agonist at SSTR5. These studies reveal that two different somatostatin receptor subtypes, SSTR2 and SSTR5, can mediate the inhibition of an L-type Ca2+ channel in AtT-20 cells by somatostatin. The receptor subtype responses can be distinguished by selective agonists and antagonists and are regulated differently by agonist pretreatment. The inhibition of Ca2+ influx into endocrine cells and neurons may be a major cellular mechanism by which somatostatin modulates hormone and neurotransmitter release. Our results reveal that at least two receptor subtypes can mediate this cellular response.
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Affiliation(s)
- M Tallent
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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24
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Abstract
1. Somatostatin (SRIF) exerts diverse physiological actions in the body including regulation of hormone and neurotransmitter release and neuronal firing activity. Analogs of SRIF are used clinically to treat tumors and cancers and to block the hypersecretion of growth hormone in acromegaly. 2. The recent cloning of five SRIF receptor subtypes has allowed for the identification of the molecular basis of the cellular actions of SRIF. The ligand binding domains and regions involved in coupling to G proteins and cellular effector systems are being identified and the processes by which SRIF inhibits cell growth and proliferation are being established. Furthermore, subtype selective agonists have been generated which are being used to investigate the specific biological roles of each SRIF receptor subtypes. 3. Such information will be useful in developing a new generation of SRIF drugs that could be employed to treat metabolic diseases, disorders of the gut, cancer and abnormalities in the central nervous system such as epilepsy and Alzheimer's disease.
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Affiliation(s)
- T Reisine
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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25
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Abstract
The neuropeptide somatostatin is widely distributed in the central nervous system and in peripheral tissues and may be involved in the regulation of a number of physiological functions including movement and cognition. Somatostatin may also have a role in the development of the central nervous system, in particular, the cerebellum and spinal cord. Somatostatin induces its actions by interacting with a family of membrane associated receptors. Recently, five somatostatin receptors have been cloned and referred to as SSTR1-SSTR5. The distribution of the expression of the mRNAs for these receptors are distinct but overlapping. Preliminary pharmacological analysis of these receptors may lead to the development of selective ligands at these receptors. These compounds may be useful in identifying the selective functions of these receptor subtypes. Some somatostatin analogues have antiproliferative actions and are used presently to treat carcinoids. Development of subtype selective somatostatin analogues could be helpful in further identifying somatostatin receptor-expressing tumors and in the treatment of cancer. The cloning of these receptors has now opened up the possibility of more clearly investigating the functions of somatostatin in the brain and peripheral tissues and will facilitate the generation of new somatostatin drugs that may be employed for the treatment of a number of diseases.
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Affiliation(s)
- T Reisine
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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Amartey JK. Technetium-99m labeled somatostatin and analogs: synthesis, characterization and in vivo evaluation. Nucl Med Biol 1993; 20:539-43. [PMID: 8099301 DOI: 10.1016/0969-8051(93)90084-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Technetium-99m complexes of somatostatin and analogs were synthesized following the introduction of sulfhydryl groups with 2-iminothiolane (Traut's Reagent). In rats the complex was taken up by the liver, kidneys, adrenals, lungs and the pancreas. Analysis of urine samples of treated rats showed that the radiochemicals have reasonably good in vivo stability. This implies that the complexes may be potentially useful for biochemical characterization of somatostatin receptors and also in scintigraphic detection of somatostatin receptor positive tumors, especially for metastatic deposits in patients on somatostatin therapy.
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Affiliation(s)
- J K Amartey
- Radionuclide and Cyclotron Operations Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia
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27
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Chejfec G, Kovarick P, Graham G, Eichorst M, Gould VE. Neuroendocrine carcinoma of the stomach with extensive somatostatin immunoreactivity. Ultrastruct Pathol 1992; 16:537-45. [PMID: 1359688 DOI: 10.3109/01913129209061545] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Upper gastrointestinal tract neuroendocrine tumors producing predominantly somatostatin have thus far been described only in the duodenum; their characteristic features include the frequent presence of psammoma bodies (psammomatous somatostinomas), and the association with von Recklinghausen's neurofibromatosis. Gastric neuroendocrine tumors, on the other hand, tend to display immunoreactivity to serotonin but may include small subpopulations producing gastrin, motilin, pancreatic polypeptide, and somatostatin. In this report we describe a neuroendocrine carcinoma of the stomach with rapidly fatal outcome, displaying neurosecretory granules by electron microscopy and immunoreactivity to pan-neuroendocrine markers, ie, chromogranin and neuron-specific enolase. The only neuroendocrine regulatory peptide detected in the tumor was somatostatin, identified by immunohistochemistry in the majority of neoplastic cells. In contrast with duodenal somatostinomas, there were no psammoma bodies and no demonstrable association with von Recklinghausen's neurofibromatosis. To our knowledge this appears to be the first report of a malignant neuroendocrine tumor with diffuse somatostatin immunoreactivity.
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Affiliation(s)
- G Chejfec
- Department of Pathology, Hines Veterans Administration Hospital, Illinois 60141
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28
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Mozell EJ, Woltering EA, O'Dorisio TM. Non-endocrine applications of somatostatin and octreotide acetate: facts and flights of fancy. Dis Mon 1991; 37:749-848. [PMID: 1683832 DOI: 10.1016/s0011-5029(05)80015-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Somatostatin, originally detected by Krulich and ultimately isolated by Brazeau, was initially described as a growth hormone release-inhibiting factor. Subsequent investigation into the use of native somatostatin and the development of long-acting somatostatin analogues, especially octreotide acetate, have fostered increasing uses of these compounds. Though the clinical and investigational uses of somatostatin and its analogues are varied, one central theme remains constant: the ability of these agents to suppress circulating peptide levels. This article, a review of the current non-endocrine applications of somatostatin and its analogues, covers a wide range of potential applications for somatostatin-like compounds. These include use in cirrhosis and variceal bleeding, peptic ulcer disease, pancreatic fistulas, acute and chronic pancreatitis, dumping syndrome, cancer therapy, small bowel fistulas, psoriasis, pain control, and autonomic hypotension. Somatostatin may also play a role in the development and potential treatment of neurologic disease and may have profound found influence on behavior.
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Affiliation(s)
- E J Mozell
- Department of Surgery, Oregon Health Sciences University, Portland
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30
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Mozell E, Stenzel P, Woltering EA, Rösch J, O'Dorisio TM. Functional endocrine tumors of the pancreas: clinical presentation, diagnosis, and treatment. Curr Probl Surg 1990; 27:301-86. [PMID: 1973365 DOI: 10.1016/0011-3840(90)90025-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- E Mozell
- Department of Surgery, Oregon Health Sciences University, Portland
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31
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Rosenberg JM. Octreotide: a synthetic analog of somatostatin. DRUG INTELLIGENCE & CLINICAL PHARMACY 1988; 22:748-54. [PMID: 3068036 DOI: 10.1177/106002808802201001] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Octreotide is an investigational synthetic peptide exhibiting actions similar to those of endogenous somatostatin. It has a longer half-life than the native hormone and can be administered by subcutaneous injection. Octreotide inhibits the secretion of growth hormone and numerous regulatory peptides of the gastroenteropancreatic system. Trials evaluating the clinical utility of octreotide indicate efficacy in the management of symptoms associated with acromegaly and hypersecretory neuroendocrine tumors, and in the control of nontumoral secretory diarrheas. Octreotide therapy is well tolerated. This agent should prove useful in the symptomatic control of a number of rare hypersecretory disorders.
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Affiliation(s)
- J M Rosenberg
- Division of Pharmacy Practice, Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201
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Reichlin S. Somatostatin: historical aspects. SCANDINAVIAN JOURNAL OF GASTROENTEROLOGY. SUPPLEMENT 1986; 119:1-10. [PMID: 2876490 DOI: 10.3109/00365528609087426] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Somatostatin, in essence an almost universal chalone, initially described as a 14 amino-acid-long peptide that inhibits growth hormone (GH) release, has been shown to be one of a family of related peptides, ubiquitous in distribution and versatile as a paracrine factor with a potentially important role in the regulation of gut, pancreatic, and nervous system function, in addition to its well-recognized influence on the pituitary secretion of GH and thyroid-stimulating hormone. With the development of new super agonists, it has become possible to manipulate the endocrine milieu, to modify gut, pancreatic, and pituitary function, and, in the case of several diseases such as acromegaly and intractable diarrhoea, to make a significant advance in therapy.
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34
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Morley JE, Bartness TJ, Gosnell BA, Levine AS. Peptidergic regulation of feeding. INTERNATIONAL REVIEW OF NEUROBIOLOGY 1985; 27:207-98. [PMID: 2867979 DOI: 10.1016/s0074-7742(08)60559-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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35
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36
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Verspohl EJ, Händel M, Hagenloh I, Ammon HP. In vitro effect of exogenous insulin on insulin secretion. Studies with glucose, leucine, arginine, aminophylline and tolbutamide. ACTA DIABETOLOGICA LATINA 1982; 19:303-17. [PMID: 6758458 DOI: 10.1007/bf02629253] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Using rat pancreatic islets and the perfused rat pancreas, the effect of exogenous insulin on insulin secretion mediated by glucose, leucine, arginine, aminophylline and tolbutamide was studied. (1) In both systems the insulin releasing capacity of glucose was inhibited by exogenous insulin. In the perfused pancreas the inhibition concerned the first and the second phase of insulin release; (2) the EC50 (half-maximal inhibitory effect of insulin on glucose-induced insulin secretion) in islets was 1.2 nM (= 160 microU/ml) and 2.8 nM (390 microU/ml) in perfused pancreas; (3) exogenous insulin also inhibited insulin release in response to leucine and arginine in the isolated islet system and in the perfused pancreas; (4) using aminophylline and tolbutamide in combination with glucose, the extent of the inhibitory effect of insulin was in the range of the inhibitory effect when glucose was used alone as stimulator in islets. Data suggest that the insulinogenic action of physiological stimulators including glucose, leucine and arginine is inhibited by exogenous insulin whereas this seems not to be the case when insulin release was stimulated by aminophylline and tolbutamide. Comparing the EC50s, isolated islets seem to be more sensitive to inhibition than the perfused pancreas when glucose was used as stimulator. As far as glucose is concerned the inhibitory effect seems to depend on the extent of its concentration and/or the extent to which the mechanism of insulin release is sensitive to stimulation. The EC50 of the inhibitory effect of exogenous insulin was in the range of dissociation constant of binding of insulin to insulin receptors of islets.
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37
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38
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Van Noorden S, Ostberg Y, Pearse AG. Localization of somatostatin-like immunoreactivity in the pancreatic islets of the hagfish, Myxine glutinosa and the lamprey Lampetra fluviatilis. Cell Tissue Res 1977; 177:281-5. [PMID: 319906 DOI: 10.1007/bf00221088] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Somatostatin-like immunofluorescence has been found by immunostaining in cells of the bile duct mucosa and pancreatic islet parenchyma of the hagfish, Myxine glutinosa, and the islet lobules of the lamprey, Lampetra fluviatilis.
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Abstract
The gastrointestinal tract is a large and complex endocrine organ. Elucidation of its nature, and the actions of its individual hormonal components, has advanced in recent years following the purification and sequencing of six probable hormones and the subsequent development of radioimmunoassay techniques for their measurement and immunocytochemistry for the determination of their cellular origin. Immunoassay and immunocytochemistry are clearly complimentary to each other in providing a fuller understanding of the dynamics of endocrine function at the cellular level. This is illustrated in the examples described in this paper.
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Mahler RJ. The pathogenesis of pancreatic islet cell hyperplasia and insulin insensitivity in obesity. ADVANCES IN METABOLIC DISORDERS 1974; 7:213-41. [PMID: 4607214 DOI: 10.1016/b978-0-12-027307-2.50016-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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42
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Deconinck JF, Van Assche FA, Potvliege PR, Gepts W. The ultrastructure of the human pancreatic islets. II. The islets of neonates. Diabetologia 1972; 8:326-33. [PMID: 4565829 DOI: 10.1007/bf01218493] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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43
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[Isolated mouse islets as a model for studying insulin release]. ACTA DIABETOLOGICA LATINA 1971; 8:649-79. [PMID: 4942530 DOI: 10.1007/bf01550894] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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44
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Hinz M, Katsilambros N, Schweitzer B, Raptis S, Pfeiffer EF. The role of the exocrine pancreas in the stimulation of insulin secretion by intestinal hormones. I. The effect of pancreozymin, secretin, gastrin-pentapeptide and of glucagon upon insulin secretion of isolated islets of rat pancreas. Diabetologia 1971; 7:1-5. [PMID: 4926758 DOI: 10.1007/bf02346246] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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45
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46
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Stauffacher W, Orci L, Cameron DP, Burr IM, Renold AE. Spontaneous hyperglycemia and-or obesity in laboratory rodents: an example of the possible usefulness of animal disease models with both genetic and environmental components. RECENT PROGRESS IN HORMONE RESEARCH 1971; 27:41-95. [PMID: 5003638 DOI: 10.1016/b978-0-12-571127-2.50026-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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47
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Strautz RL. Studies of hereditary-obese mice (obob) after implantation of pancreatic islets in Millipore filter capsules. Diabetologia 1970; 6:306-12. [PMID: 4914667 DOI: 10.1007/bf01212243] [Citation(s) in RCA: 86] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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48
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49
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Barrington EJ. Opening address at the Fifth Conference of European Comparative Endocrinologists, Utrecht, The Netherlands, 24-29 August 1969. Gen Comp Endocrinol 1969; 13:482-8. [PMID: 4933206 DOI: 10.1016/0016-6480(69)90273-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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