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Langhans W, Watts AG, Spector AC. The elusive cephalic phase insulin response: triggers, mechanisms, and functions. Physiol Rev 2023; 103:1423-1485. [PMID: 36422994 PMCID: PMC9942918 DOI: 10.1152/physrev.00025.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 11/04/2022] [Accepted: 11/20/2022] [Indexed: 11/25/2022] Open
Abstract
The cephalic phase insulin response (CPIR) is classically defined as a head receptor-induced early release of insulin during eating that precedes a postabsorptive rise in blood glucose. Here we discuss, first, the various stimuli that elicit the CPIR and the sensory signaling pathways (sensory limb) involved; second, the efferent pathways that control the various endocrine events associated with eating (motor limb); and third, what is known about the central integrative processes linking the sensory and motor limbs. Fourth, in doing so, we identify open questions and problems with respect to the CPIR in general. Specifically, we consider test conditions that allow, or may not allow, the stimulus to reach the potentially relevant taste receptors and to trigger a CPIR. The possible significance of sweetness and palatability as crucial stimulus features and whether conditioning plays a role in the CPIR are also discussed. Moreover, we ponder the utility of the strict classical CPIR definition based on what is known about the effects of vagal motor neuron activation and thereby acetylcholine on the β-cells, together with the difficulties of the accurate assessment of insulin release. Finally, we weigh the evidence of the physiological and clinical relevance of the cephalic contribution to the release of insulin that occurs during and after a meal. These points are critical for the interpretation of the existing data, and they support a sharper focus on the role of head receptors in the overall insulin response to eating rather than relying solely on the classical CPIR definition.
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Affiliation(s)
- Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zürich, Schwerzenbach, Switzerland
| | - Alan G Watts
- Department of Biological Sciences, USC Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California
| | - Alan C Spector
- Department of Psychology and Program in Neuroscience, Florida State University, Tallahassee, Florida
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2
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Use of c-peptide as a measure of cephalic phase insulin release in humans. Physiol Behav 2022; 255:113940. [PMID: 35961609 PMCID: PMC9993810 DOI: 10.1016/j.physbeh.2022.113940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 02/08/2023]
Abstract
Cephalic phase insulin release (CPIR) is a rapid pulse of insulin secreted within minutes of food-related sensory stimulation. Understanding the mechanisms underlying CPIR in humans has been hindered by its small observed effect size and high variability within and between studies. One contributing factor to these limitations may be the use of peripherally measured insulin as an indicator of secreted insulin, since a substantial portion of insulin is metabolized by the liver before delivery to peripheral circulation. Here, we investigated the use of c-peptide, which is co-secreted in equimolar amounts to insulin from pancreatic beta cells, as a proxy for insulin secretion during the cephalic phase period. Changes in insulin and c-peptide were monitored in 18 adults over two repeated sessions following oral stimulation with a sucrose-containing gelatin stimulus. We found that, on average, insulin and c-peptide release followed a similar time course over the cephalic phase period, but that c-peptide showed a greater effect size. Importantly, when insulin and c-peptide concentrations were compared across sessions, we found that changes in c-peptide were significantly correlated at the 2 min (r = 0.50, p = 0.03) and 4 min (r = 0.65, p = 0.003) time points, as well as when participants' highest c-peptide concentrations were considered (r = 0.64, p = 0.004). In contrast, no significant correlations were observed for changes in insulin measured from the sessions (r = -0.06-0.35, p > 0.05). Herein, we detail the individual variability of insulin and c-peptide concentrations measured during the cephalic phase period, and identify c-peptide as a valuable metric for insulin secretion alongside insulin concentrations when investigating CPIR.
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3
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Chen CC, Peng SJ, Wu PY, Chien HJ, Lee CY, Chung MH, Tang SC. Heterogeneity and neurovascular integration of intraportally transplanted islets revealed by 3-D mouse liver histology. Am J Physiol Endocrinol Metab 2021; 320:E1007-E1019. [PMID: 33900850 DOI: 10.1152/ajpendo.00605.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Intraportal islet transplantation has been clinically applied for treatment of unstable type 1 diabetes. However, in the liver, systematic assessment of the dispersed islet grafts and the graft-hepatic integration remains difficult, even in animal models. This is due to the lack of global and in-depth analyses of the transplanted islets and their microenvironment. Here, we apply three-dimensional (3-D) mouse liver histology to investigate the islet graft microstructure, vasculature, and innervation. Streptozotocin-induced diabetic mice were used in syngeneic intraportal islet transplantation to achieve euglycemia. Optically cleared livers were prepared to enable 3-D morphological and quantitative analyses of the engrafted islets. 3-D image data reveal the clot- and plaque-like islet grafts in the liver: the former are derived from islet emboli and associated with ischemia, whereas the latter (minority) resemble the plaques on the walls of portal vessels (e.g., at the bifurcation) with mild, if any, perigraft tissue damage. Three weeks after transplantation, both types of grafts are revascularized, yet significantly more lymphatics are associated with the plaque- than clot-like grafts. Regarding the islet reinnervation, both types of grafts connect to the periportal nerve plexus and develop peri- and intragraft innervation. Specifically, the sympathetic axons and varicosities contact the α-cells, highlighting the graft-host neural integration. We present the heterogeneity of the intraportally transplanted islets and the graft-host neurovascular integration in mice. Our work provides the technical and morphological foundation for future high-definitional 3-D tissue and cellular analyses of human islet grafts in the liver.NEW & NOTEWORTHY Modern 3-D histology identifies the clot- and plaque-like islet grafts in the mouse liver, which otherwise cannot be distinguished with the standard microtome-based histology. The two types of grafts are similar in blood microvessel density and sympathetic reinnervation. Their differences, however, are their locations, severity of associated liver injury, and access to lymphatic vessels. Our work provides the technical and morphological foundation for future high-definitional 3-D tissue/cellular analyses of human islet grafts in the liver.
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Affiliation(s)
- Chien-Chia Chen
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Jung Peng
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Pei-Yu Wu
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Pathology, National Taiwan University Hospital-Hsinchu Branch, Hsinchu, Taiwan
| | - Shiue-Cheng Tang
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
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4
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Zeigerer A, Sekar R, Kleinert M, Nason S, Habegger KM, Müller TD. Glucagon's Metabolic Action in Health and Disease. Compr Physiol 2021; 11:1759-1783. [PMID: 33792899 PMCID: PMC8513137 DOI: 10.1002/cphy.c200013] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Discovered almost simultaneously with insulin, glucagon is a pleiotropic hormone with metabolic action that goes far beyond its classical role to increase blood glucose. Albeit best known for its ability to directly act on the liver to increase de novo glucose production and to inhibit glycogen breakdown, glucagon lowers body weight by decreasing food intake and by increasing metabolic rate. Glucagon further promotes lipolysis and lipid oxidation and has positive chronotropic and inotropic effects in the heart. Interestingly, recent decades have witnessed a remarkable renaissance of glucagon's biology with the acknowledgment that glucagon has pharmacological value beyond its classical use as rescue medication to treat severe hypoglycemia. In this article, we summarize the multifaceted nature of glucagon with a special focus on its hepatic action and discuss the pharmacological potential of either agonizing or antagonizing the glucagon receptor for health and disease. © 2021 American Physiological Society. Compr Physiol 11:1759-1783, 2021.
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Affiliation(s)
- Anja Zeigerer
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Revathi Sekar
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Maximilian Kleinert
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute for Diabetes and Obesity, Helmholtz Center Munich, Neuherberg, Germany
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Shelly Nason
- Comprehensive Diabetes Center, Department of Medicine - Endocrinology, Diabetes & Metabolism, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Kirk M. Habegger
- Comprehensive Diabetes Center, Department of Medicine - Endocrinology, Diabetes & Metabolism, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Timo D. Müller
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute for Diabetes and Obesity, Helmholtz Center Munich, Neuherberg, Germany
- Department of Pharmacology, Experimental Therapy and Toxicology, Institute of Experimental and Clinical Pharmacology and Pharmacogenomics, Eberhard Karls University Hospitals and Clinics, Tübingen, Germany
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5
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Food anticipatory hormonal responses: A systematic review of animal and human studies. Neurosci Biobehav Rev 2021; 126:447-464. [PMID: 33812978 DOI: 10.1016/j.neubiorev.2021.03.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 01/31/2021] [Accepted: 03/27/2021] [Indexed: 12/31/2022]
Abstract
Food anticipatory hormonal responses (cephalic responses) are proactive physiological processes, that allow animals to prepare for food ingestion by modulating their hormonal levels in response to food cues. This process is important for digesting food, metabolizing nutrients and maintaining glucose levels within homeostasis. In this systematic review, we summarize the evidence from animal and human research on cephalic responses. Thirty-six animal and fifty-three human studies were included. The majority (88 %) of studies demonstrated that hormonal levels are changed in response to cues previously associated with food intake, such as feeding time, smell, and sight of food. Most evidence comes from studies on insulin, ghrelin, pancreatic polypeptide, glucagon, and c-peptide. Moreover, impaired cephalic responses were found in disorders related to metabolism and food intake such as diabetes, pancreatic insufficiency, obesity, and eating disorders, which opens discussions about the etiological mechanisms of these disorders as well as on potential therapeutic opportunities.
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Campbell-Thompson M, Butterworth EA, Boatwright JL, Nair MA, Nasif LH, Nasif K, Revell AY, Riva A, Mathews CE, Gerling IC, Schatz DA, Atkinson MA. Islet sympathetic innervation and islet neuropathology in patients with type 1 diabetes. Sci Rep 2021; 11:6562. [PMID: 33753784 PMCID: PMC7985489 DOI: 10.1038/s41598-021-85659-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/04/2021] [Indexed: 02/07/2023] Open
Abstract
Dysregulation of glucagon secretion in type 1 diabetes (T1D) involves hypersecretion during postprandial states, but insufficient secretion during hypoglycemia. The sympathetic nervous system regulates glucagon secretion. To investigate islet sympathetic innervation in T1D, sympathetic tyrosine hydroxylase (TH) axons were analyzed in control non-diabetic organ donors, non-diabetic islet autoantibody-positive individuals (AAb), and age-matched persons with T1D. Islet TH axon numbers and density were significantly decreased in AAb compared to T1D with no significant differences observed in exocrine TH axon volume or lengths between groups. TH axons were in close approximation to islet α-cells in T1D individuals with long-standing diabetes. Islet RNA-sequencing and qRT-PCR analyses identified significant alterations in noradrenalin degradation, α-adrenergic signaling, cardiac β-adrenergic signaling, catecholamine biosynthesis, and additional neuropathology pathways. The close approximation of TH axons at islet α-cells supports a model for sympathetic efferent neurons directly regulating glucagon secretion. Sympathetic islet innervation and intrinsic adrenergic signaling pathways could be novel targets for improving glucagon secretion in T1D.
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Affiliation(s)
- Martha Campbell-Thompson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA. .,Department of Biomedical Engineering, College of Engineering, University of Florida, Gainesville, FL, 32610, USA.
| | - Elizabeth A Butterworth
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - J Lucas Boatwright
- Bioinformatics Core, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, 32610, USA
| | - Malavika A Nair
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Lith H Nasif
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Kamal Nasif
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Andy Y Revell
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Alberto Riva
- Bioinformatics Core, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, 32610, USA
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Ivan C Gerling
- Department of Medicine-Endocrinology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Desmond A Schatz
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Mark A Atkinson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.,Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
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7
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Grüneis V, Schweiger K, Galassi C, Karl CM, Treml J, Ley JP, König J, Krammer GE, Somoza V, Lieder B. Sweetness Perception is not Involved in the Regulation of Blood Glucose after Oral Application of Sucrose and Glucose Solutions in Healthy Male Subjects. Mol Nutr Food Res 2021; 65:e2000472. [PMID: 33249735 PMCID: PMC7900990 DOI: 10.1002/mnfr.202000472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/07/2020] [Indexed: 01/01/2023]
Abstract
SCOPE This study investigates the effect of the sweetness of a sucrose versus an isocaloric glucose solution in dietary concentrations on blood glucose regulation by adjusting the sweetness level using the sweet taste inhibitor lactisole. METHODS AND RESULTS A total of 27 healthy males participated in this randomized, crossover study with four treatments: 10% glucose, 10% sucrose, 10% sucrose + 60 ppm lactisole, and 10% glucose + 60 ppm lactisole. Plasma glucose, insulin, glucagon-like peptide 1, and glucagon levels are measured at baseline and 15, 30, 60, 90, and 120 min after beverage consumption. Test subjects rated the sucrose solution to be sweeter than the isocaloric glucose solution, whereas no difference in sweetness is reported after addition of lactisole to the sucrose solution. Administration of the less sweet glucose solution versus sucrose led to higher blood glucose levels after 30 min, as reflected by a lower ΔAUC for sucrose (1072 ± 136) than for glucose (1567 ± 231). Application of lactisole leads to no differences in glucose, insulin, or glucagon responses induced by sucrose or glucose. CONCLUSION The results indicate that the structure of the carbohydrate has a stronger impact on the regulation of blood glucose levels than the perceived sweetness.
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Affiliation(s)
- Verena Grüneis
- Christian Doppler Laboratory for Taste ResearchFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Kerstin Schweiger
- Department of Physiological ChemistryFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Claudia Galassi
- Christian Doppler Laboratory for Taste ResearchFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Corinna M. Karl
- Christian Doppler Laboratory for Taste ResearchFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Julia Treml
- Christian Doppler Laboratory for Taste ResearchFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Jakob P. Ley
- Symrise AGMuehlenfeldstrasse 1Holzminden37603Germany
| | - Jürgen König
- Department of Nutritional ScienceFaculty of Life SciencesUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | | | - Veronika Somoza
- Department of Physiological ChemistryFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Barbara Lieder
- Christian Doppler Laboratory for Taste ResearchFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
- Department of Physiological ChemistryFaculty of ChemistryUniversity of ViennaAlthanstrasse 14Vienna1090Austria
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8
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Wiedemann SJ, Rachid L, Illigens B, Böni-Schnetzler M, Donath MY. Evidence for cephalic phase insulin release in humans: A systematic review and meta-analysis. Appetite 2020; 155:104792. [DOI: 10.1016/j.appet.2020.104792] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 06/24/2020] [Accepted: 06/24/2020] [Indexed: 02/02/2023]
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9
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Lasschuijt MP, Mars M, de Graaf C, Smeets PAM. Endocrine Cephalic Phase Responses to Food Cues: A Systematic Review. Adv Nutr 2020; 11:1364-1383. [PMID: 32516803 PMCID: PMC7490153 DOI: 10.1093/advances/nmaa059] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/10/2020] [Accepted: 04/29/2020] [Indexed: 01/16/2023] Open
Abstract
Cephalic phase responses (CPRs) are conditioned anticipatory physiological responses to food cues. They occur before nutrient absorption and are hypothesized to be important for satiation and glucose homeostasis. Cephalic phase insulin responses (CPIRs) and pancreatic polypeptide responses (CPPPRs) are found consistently in animals, but human literature is inconclusive. We performed a systematic review of human studies to determine the magnitude and onset time of these CPRs. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to develop a search strategy. The terms included in the search strategy were cephalic or hormone response or endocrine response combined with insulin and pancreatic polypeptide (PP). The following databases were searched: Scopus (Elsevier), Science Direct, PubMed, Google Scholar, and The Cochrane Library. Initially, 582 original research articles were found, 50 were included for analysis. An insulin increase (≥1μIU/mL) was observed in 41% of the treatments (total n = 119). In 22% of all treatments the increase was significant from baseline. The median (IQR) insulin increase was 2.5 (1.6-4.5) μIU/mL, 30% above baseline at 5± 3 min after food cue onset (based on study treatments that induced ≥1 μIU/mL insulin increase). A PP increase (>10 pg/mL) was found in 48% of the treatments (total n = 42). In 21% of the treatments, the increase was significant from baseline. The median (IQR) PP increase was 99 (26-156) pg/mL, 68% above baseline at 9± 4 min after food cue onset (based on study treatments that induced ≥1 μIU/mL insulin increase). In conclusion, CPIRs are small compared with spontaneous fluctuations. Although CPPPRs are of a larger magnitude, both show substantial variation in magnitude and onset time. We found little evidence for CPIR or CPPPR affecting functional outcomes, that is, satiation and glucose homeostasis. Therefore, CPRs do not seem to be biologically meaningful in daily life.
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Affiliation(s)
- Marlou P Lasschuijt
- Division of Human Nutrition and Health, Wageningen University & Research, Wageningen, The Netherlands
| | - Monica Mars
- Division of Human Nutrition and Health, Wageningen University & Research, Wageningen, The Netherlands
| | - Cees de Graaf
- Division of Human Nutrition and Health, Wageningen University & Research, Wageningen, The Netherlands
| | - Paul A M Smeets
- Division of Human Nutrition and Health, Wageningen University & Research, Wageningen, The Netherlands
- Image Sciences Institute, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
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10
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Chien HJ, Chiang TC, Peng SJ, Chung MH, Chou YH, Lee CY, Jeng YM, Tien YW, Tang SC. Human pancreatic afferent and efferent nerves: mapping and 3-D illustration of exocrine, endocrine, and adipose innervation. Am J Physiol Gastrointest Liver Physiol 2019; 317:G694-G706. [PMID: 31509431 DOI: 10.1152/ajpgi.00116.2019] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The pancreas consists of both the exocrine (acini and ducts) and endocrine (islets) compartments to participate in and regulate the body's digestive and metabolic activities. These activities are subjected to neural modulation, but characterization of the human pancreatic afferent and efferent nerves remains difficult because of the lack of three-dimensional (3-D) image data. Here we prepare transparent human donor pancreases for 3-D histology to reveal the pancreatic microstructure, vasculature, and innervation in a global and integrated fashion. The pancreatic neural network consists of the substance P (SP)-positive sensory (afferent) nerves, the vesicular acetylcholine transporter (VAChT)-positive parasympathetic (efferent) nerves, and the tyrosine hydroxylase (TH)-positive sympathetic (efferent) nerves. The SP+ afferent nerves were found residing along the basal domain of the interlobular ducts. The VAChT+ and TH+ efferent nerves were identified at the peri-acinar and perivascular spaces, which follow the blood vessels to the islets. In the intrapancreatic ganglia, the SP+ (scattered minority, ~7%) and VAChT+ neurons co-localize, suggesting a local afferent-efferent interaction. Compared with the mouse pancreas, the human pancreas differs in 1) the lack of SP+ afferent nerves in the islet, 2) the lower ganglionic density, and 3) the obvious presence of VAChT+ and TH+ nerves around the intralobular adipocytes. The latter implicates the neural influence on the pancreatic steatosis. Overall, our 3-D image data reveal the human pancreatic afferent and efferent innervation patterns and provide the anatomical foundation for future high-definition analyses of neural remodeling in human pancreatic diseases.NEW & NOTEWORTHY Modern three-dimensional (3-D) histology with multiplex optical signals identifies the afferent and efferent innervation patterns of human pancreas, which otherwise cannot be defined with standard histology. Our 3-D image data reveal the unexpected association of sensory and parasympathetic nerves/neurons in the intrapancreatic ganglia and identify the sympathetic and parasympathetic nerve contacts with the infiltrated adipocytes. The multiplex approach offers a new way to characterize the human pancreas in remodeling (e.g., fatty infiltration and duct lesion progression).
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Affiliation(s)
- Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Jung Peng
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Pathology, National Taiwan University Hospital-Hsinchu Branch, Hsinchu, Taiwan
| | - Ya-Hsien Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
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11
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Do non-nutritive sweeteners influence acute glucose homeostasis in humans? A systematic review. Physiol Behav 2017; 182:17-26. [PMID: 28939430 DOI: 10.1016/j.physbeh.2017.09.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 08/17/2017] [Accepted: 09/18/2017] [Indexed: 12/16/2022]
Abstract
The human body associates sensory cues with metabolic consequences. Exposure to sweet-tasting sugars - even in the absence of ingestion - triggers physiological responses that are associated with carbohydrate digestion, absorption and metabolism. These responses include the release of insulin and incretin hormones, which work to reduce blood glucose. For this reason, non-nutritive sweeteners (NNS) have been posited to trigger similar physiological responses and reduce postprandial blood glucose concentrations. The first part of this review presents a brief overview of sweet taste receptor activation in the oral cavity and gastrointestinal tract and the ensuing physiological responses related to glucose homeostasis. The second part of this review contains a systematic literature review that tested the hypothesis that NNS use improves glucose regulation postprandially. Studies were grouped based on sweet taste receptor stimulation paradigms, including pre-ingestive stimulation, ingestion of NNS alone, co-ingestion of NNS with foods, and using NNS as preloads to influence subsequent blood glucose excursions. In summary, the review found that NNS triggered physiological responses, albeit inconsistently, yet failed to significantly lower blood glucose levels in almost all studies.
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12
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Abstract
Contrary to dogma, much physiological regulation utilizes learning from past experience to make responses that preemptively and effectively neutralize anticipated regulatory challenges. Understanding physiological regulation therefore requires expanding explanatory models beyond homeostasis and allostasis to emphasize the prominence of conditioning.
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Affiliation(s)
- Douglas S Ramsay
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA 98195, USA
| | - Stephen C Woods
- Department of Psychiatry and Behavioral Neuroscience, School of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA.
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13
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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: 310] [Impact Index Per Article: 34.4] [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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Gylfe E, Tengholm A. Neurotransmitter control of islet hormone pulsatility. Diabetes Obes Metab 2014; 16 Suppl 1:102-10. [PMID: 25200303 DOI: 10.1111/dom.12345] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 04/15/2014] [Indexed: 12/26/2022]
Abstract
Pulsatile secretion is an inherent property of hormone-releasing pancreatic islet cells. This secretory pattern is physiologically important and compromised in diabetes. Neurotransmitters released from islet cells may shape the pulses in auto/paracrine feedback loops. Within islets, glucose-stimulated β-cells couple via gap junctions to generate synchronized insulin pulses. In contrast, α- and δ-cells lack gap junctions, and glucagon release from islets stimulated by lack of glucose is non-pulsatile. Increasing glucose concentrations gradually inhibit glucagon secretion by α-cell-intrinsic mechanism/s. Further glucose elevation will stimulate pulsatile insulin release and co-secretion of neurotransmitters. Excitatory ATP may synchronize β-cells with δ-cells to generate coinciding pulses of insulin and somatostatin. Inhibitory neurotransmitters from β- and δ-cells can then generate antiphase pulses of glucagon release. Neurotransmitters released from intrapancreatic ganglia are required to synchronize β-cells between islets to coordinate insulin pulsatility from the entire pancreas, whereas paracrine intra-islet effects still suffice to explain coordinated pulsatile release of glucagon and somatostatin. The present review discusses how neurotransmitters contribute to the pulsatility at different levels of integration.
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Affiliation(s)
- E Gylfe
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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15
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Abstract
Over the past 30 years, it has been established that hormones produced by the gut, pancreas, and adipose tissue are key players in the control of body weight. These hormones act through a complex neuroendocrine system, including the hypothalamus, to regulate metabolism and energy homeostasis. In obesity, this homeostatic balance is disrupted, either through alterations in the levels of these hormones or through resistance to their actions. Alterations in gut hormone secretion following gastric bypass surgery are likely to underlie the dramatic and persistent loss of weight following this procedure, as well as the observed amelioration in type 2 diabetes mellitus. Medications based on the gut hormone GLP-1 are currently in clinical use to treat type 2 diabetes mellitus and have been shown to produce weight loss. Further therapies for obesity based on other gut hormones are currently in development.
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Affiliation(s)
- Rebecca Scott
- Division of Diabetes, Endocrinology, Metabolism, Hammersmith Hospital, Imperial College London, London, United Kingdom.
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Abstract
Many questions must be considered with regard to consuming food, including when to eat, what to eat and how much to eat. Although eating is often thought to be a homeostatic behaviour, little evidence exists to suggest that eating is an automatic response to an acute shortage of energy. Instead, food intake can be considered as an integrated response over a prolonged period of time that maintains the levels of energy stored in adipocytes. When we eat is generally determined by habit, convenience or opportunity rather than need, and meals are preceded by a neurally-controlled coordinated secretion of numerous hormones that prime the digestive system for the anticipated caloric load. How much we eat is determined by satiation hormones that are secreted in response to ingested nutrients, and these signals are in turn modified by adiposity hormones that indicate the fat content of the body. In addition, many nonhomeostatic factors, including stress, learning, palatability and social influences, interact with other controllers of food intake. If a choice of food is available, what we eat is based on pleasure and past experience. This article reviews the hormones that mediate and influence these processes.
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Affiliation(s)
- Denovan P Begg
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, 2170 East Galbraith Road, Cincinnati, OH 45237, USA
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Naumann E, Trentowska M, Svaldi J. Increased salivation to mirror exposure in women with binge eating disorder. Appetite 2013; 65:103-10. [DOI: 10.1016/j.appet.2013.01.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 12/12/2012] [Accepted: 01/21/2013] [Indexed: 12/25/2022]
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Begg DP, Woods SC. Interactions between the central nervous system and pancreatic islet secretions: a historical perspective. ADVANCES IN PHYSIOLOGY EDUCATION 2013; 37:53-60. [PMID: 23471249 PMCID: PMC3776474 DOI: 10.1152/advan.00167.2012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 01/14/2013] [Indexed: 05/10/2023]
Abstract
The endocrine pancreas is richly innervated with sympathetic and parasympathetic projections from the brain. In the mid-20th century, it was established that α-adrenergic activation inhibits, whereas cholinergic stimulation promotes, insulin secretion; this demonstrated the importance of the sympathetic and parasympathetic systems in pancreatic endocrine function. It was later established that insulin injected peripherally could act within the brain, leading to the discovery of insulin and insulin receptors within the brain and the receptor-mediated transport of insulin into the central nervous system from endothelial cells. The insulin receptor within the central nervous system is widely distributed, reflecting insulin's diverse range of actions, including acting as an adiposity signal to reduce food intake and increase energy expenditure, regulation of systemic glucose responses, altering sympathetic activity, and involvement in cognitive function. As observed with central insulin administration, the pancreatic hormones glucagon, somatostatin, pancreatic polypeptide, and amylin can each also reduce food intake. Pancreatic and also gut hormones are released cephalically, in what is an important mechanism to prepare the body for a meal and prevent excessive postprandial hyperglycemia.
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Affiliation(s)
- Denovan P Begg
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH 45237, USA
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19
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Abstract
Islet hormones, especially insulin and glucagon, are important for glucose homeostasis. Insulin is a necessity for life, and disturbed insulin release results in disordered blood glucose regulation. Although isolated islets are fully capable of detecting changes in their local environment (particularly glucose fluctuations) and altering hormone release appropriately, experimentally manipulating pancreatic innervation alters islet hormone release in the whole animal. This article describes how brain may play a role in influencing and directing secretion of insulin and glucagon as a key part of the integrated physiology of blood glucose homeostasis.
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Affiliation(s)
- Mayowa A Osundiji
- Department of Medicine, Institute of Metabolic Science, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
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20
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Teff KL. How neural mediation of anticipatory and compensatory insulin release helps us tolerate food. Physiol Behav 2011; 103:44-50. [PMID: 21256146 PMCID: PMC3056926 DOI: 10.1016/j.physbeh.2011.01.012] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 01/06/2011] [Accepted: 01/12/2011] [Indexed: 11/18/2022]
Abstract
Learned anticipatory and compensatory responses allow the animal and human to maintain metabolic homeostasis during periods of nutritional challenges, either acutely within each meal or chronically during periods of overnutrition. This paper discusses the role of neurally-mediated anticipatory responses in humans and their role in glucoregulation, focusing on cephalic phase insulin and pancreatic polypeptide release as well as compensatory insulin release during the etiology of insulin resistance. The necessary stimuli required to elicit CPIR and vagal activation are discussed and the role of CPIR and vagal efferent activation in intra-meal metabolic homeostasis and during chronic nutritional challenges are reviewed.
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Affiliation(s)
- Karen L Teff
- Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, United States.
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Vahl TP, Drazen DL, Seeley RJ, D'Alessio DA, Woods SC. Meal-anticipatory glucagon-like peptide-1 secretion in rats. Endocrinology 2010; 151:569-75. [PMID: 19915164 PMCID: PMC2817629 DOI: 10.1210/en.2009-1002] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Animals anticipating a meal initiate a series of responses enabling them to better cope with the meal's metabolic impact. These responses, such as cephalic insulin, occur prior to the onset of ingestion and are especially evident in animals maintained on a meal-feeding schedule with limited but predictable access to food each day. We tested the hypothesis that meal-fed rats secrete the incretin hormone glucagon-like peptide-1 (GLP-1) cephalically when anticipating a large meal. Male Long-Evans rats were fed ad libitum (controls) or adapted to a schedule on which food was available for the same 4-h period each day (meal fed animals). Plasma GLP-1 increased in meal-fed rats over an interval from 75 to 60 min prior to feeding time, from a baseline of 10 to around 40 pm, and then returned to baseline prior to food presentation. Controls had steady plasma GLP-1 levels (10-15 pm) over the same span. Meal-fed rats also secreted cephalic insulin starting around 15 min prior to food presentation. Administration of the selective GLP-1 receptor antagonist exendin-4[desHis-1,Glu-9] prior to the premeal spike of GLP-1 caused meal-fed rats to eat significantly less food than normal, whereas administration of the antagonist after the GLP-1 spike but prior to food presentation resulted in a significant increase in food consumption. These findings document for the first time a cephalic increase of plasma GLP-1 and suggest that it functions to facilitate consumption of a large meal.
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Affiliation(s)
- Torsten P Vahl
- Department of Psychiatry, University of Cincinnati, 2170 East Galbraith Road, Cincinnati, Ohio 45237, USA
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Alcedo J, Maier W, Ch’ng Q. Sensory Influence on Homeostasis and Lifespan: Molecules and Circuits. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010. [DOI: 10.1007/978-1-4419-7002-2_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Frystyk J, Ritzel RA, Maubach J, Büsing M, Lück R, Klempnauer J, Schmiegel W, Nauck MA. Comparison of pancreas-transplanted type 1 diabetic patients with portal-venous versus systemic-venous graft drainage: impact on glucose regulatory hormones and the growth hormone/insulin-like growth factor-I axis. J Clin Endocrinol Metab 2008; 93:1758-66. [PMID: 18319317 DOI: 10.1210/jc.2007-2350] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
CONTEXT Pancreas grafts can be drained through the iliac vein (systemic drainage) or the portal vein. OBJECTIVE We hypothesized that normalization of portal insulin in patients with portal pancreas graft drainage stimulates the GH/IGF-I axis and thereby contributes to glucose control. METHODS We compared patients after combined kidney and pancreas transplantation with portal drainage (n = 7) to patients with systemic drainage of the pancreas graft (n = 8) and nondiabetic controls (n = 8). Overnight fasting sera were analyzed for free and total IGF-I and IGF-binding proteins. Glucose regulatory hormones were examined after an oral glucose tolerance test and GH after stimulation with GHRH. RESULTS Systemic drainage led to higher basal and stimulated insulin levels than portal drainage (P < 0.05), but increments in response to oral glucose were reduced in both transplanted groups (P < 0.05 vs. controls). However, glucose tolerance was similar in all groups. Circulating free and total IGF-I and IGF-binding protein-3 were similar to control levels in the systemic drainage group but elevated in the portal drainage group (P < 0.05). Consistently, the GH response was reduced in the portal drainage group (P < 0.05 vs. controls) and correlated inversely with free IGF-I (r = -0.63, P < 0.05). CONCLUSION Portal drainage of pancreatic endocrine secretion in pancreas graft recipients raises IGF-I and lowers GH secretion. These changes might explain that glucose regulation is maintained despite lower peripheral insulin levels, compared with patients with systemic graft drainage and nondiabetic control subjects.
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Affiliation(s)
- Jan Frystyk
- Medical Research Laboratories, Aarhus University Hospital, Nørrebrogade 44, Aarhus C, Denmark.
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Woods SC, Lutz TA, Geary N, Langhans W. Pancreatic signals controlling food intake; insulin, glucagon and amylin. Philos Trans R Soc Lond B Biol Sci 2006; 361:1219-35. [PMID: 16815800 PMCID: PMC1642707 DOI: 10.1098/rstb.2006.1858] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The control of food intake and body weight by the brain relies upon the detection and integration of signals reflecting energy stores and fluxes, and their interaction with many different inputs related to food palatability and gastrointestinal handling as well as social, emotional, circadian, habitual and other situational factors. This review focuses upon the role of hormones secreted by the endocrine pancreas: hormones, which individually and collectively influence food intake, with an emphasis upon insulin, glucagon and amylin. Insulin and amylin are co-secreted by B-cells and provide a signal that reflects both circulating energy in the form of glucose and stored energy in the form of visceral adipose tissue. Insulin acts directly at the liver to suppress the synthesis and secretion of glucose, and some plasma insulin is transported into the brain and especially the mediobasal hypothalamus where it elicits a net catabolic response, particularly reduced food intake and loss of body weight. Amylin reduces meal size by stimulating neurons in the hindbrain, and there is evidence that amylin additionally functions as an adiposity signal controlling body weight as well as meal size. Glucagon is secreted from A-cells and increases glucose secretion from the liver. Glucagon acts in the liver to reduce meal size, the signal being relayed to the brain via the vagus nerves. To summarize, hormones of the endocrine pancreas are collectively at the crossroads of many aspects of energy homeostasis. Glucagon and amylin act in the short term to reduce meal size, and insulin sensitizes the brain to short-term meal-generated satiety signals; and insulin and perhaps amylin as well act over longer intervals to modulate the amount of fat maintained and defended by the brain. Hormones of the endocrine pancreas interact with receptors at many points along the gut-brain axis, from the liver to the sensory vagus nerve to the hindbrain to the hypothalamus; and their signals are conveyed both neurally and humorally. Finally, their actions include gastrointestinal and metabolic as well as behavioural effects.
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Affiliation(s)
- Stephen C Woods
- Department of Psychiatry, University of Cincinnati, OH 45237 USA.
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ZAFRA M, MOLINA F, PUERTO A. The neural/cephalic phase reflexes in the physiology of nutrition. Neurosci Biobehav Rev 2006; 30:1032-44. [DOI: 10.1016/j.neubiorev.2006.03.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 03/15/2006] [Accepted: 03/16/2006] [Indexed: 10/24/2022]
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Lechner A. Stem cells and regenerative medicine for the treatment of type 1 diabetes: the challenges lying ahead. Pediatr Diabetes 2005; 5 Suppl 2:88-93. [PMID: 15601379 DOI: 10.1111/j.1399-543x.2004.00084.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The differentiation of insulin-producing cells in vitro from embryonic or adult stem cells offers potential new treatment options for type 1 diabetes. Progress toward this goal has been made in the recent years, but substantial obstacles still remain. In order to be advantageous over the current standard regimens with exogenous insulin, any stem cell-based therapy would have to restore normal or near normal metabolic control. To achieve this, many of the complex regulatory mechanisms that control physiologic insulin secretion would have to be recreated with in vitro-generated tissue. An alternative approach would be to use the insights gained through stem cell research to develop pharmacologic agents that can induce regeneration of endogenous pancreatic islets in patients with type 1 diabetes. Such a therapy also requires extensive further research, but it could have principal advantages over tissue transplantation.
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Affiliation(s)
- Andreas Lechner
- Ludwig-Maximilians-Universität, Klinikum Grosshadern, Medizinische Klinik 2, Marchioninistr. 15, 81377 München, Germany.
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Labouré H, Van Wymelbeke V, Fantino M, Nicolaidis S. Behavioral, plasma, and calorimetric changes related to food texture modification in men. Am J Physiol Regul Integr Comp Physiol 2002; 282:R1501-11. [PMID: 11959694 DOI: 10.1152/ajpregu.00287.2001] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesized that food texture modifications might alter anticipatory reflexes, feeding behavior, and the postabsorptive consequences of ingestion. Two sets of complete meals with different textures but the same macronutrient composition were prepared. The first set was either a soup containing chunks of food (mixture) or the same soup blended until smooth (purée). The second set was either a rusk (R), a sandwich loaf (SL), or a liquid rusk meal (LR). We measured hunger and fullness feelings after ingestion of each food in a calibrated lunch, the ingestion rate, the duration between lunch and a spontaneous dinner request, the energy value, and the macronutrient composition of the ad libitum dinner. We also studied plasma modifications and respiratory gas exchanges from lunch to dinner. Feelings of hunger and fullness were not affected by texture modifications. The purée soup was consumed faster than the mixture (P < 0.05), and insulin, triacylglycerol, and energy expenditure were greater with the purée (P < 0.05). LR was less palatable than the other rusk lunch versions (P < 0.001), and R was ingested more slowly (P < 0.05). The lowest increase in plasma glucose occurred with SL, and the highest energy expenditure was seen with LR (P < 0.05). In humans, food texture modification affects not only eating patterns and palatability of ingestants but also metabolic management.
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Affiliation(s)
- Hélène Labouré
- Institut Européen des Sciences du Goût et des Comportements Alimentaires, Centre National de la Recherche Scientifique, 21000 Dijon, France.
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Pileggi A, Ricordi C, Alessiani M, Inverardi L. Factors influencing Islet of Langerhans graft function and monitoring. Clin Chim Acta 2001; 310:3-16. [PMID: 11485749 DOI: 10.1016/s0009-8981(01)00503-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Transplantation of islet of Langerhans represents a viable therapeutic option for insulin-dependent diabetes mellitus. Dramatic progress has been recently reported with the introduction of a glucocorticoid-free immunosuppressive regimen that improved success rate, namely, insulin independence for 1 year or more, from 8% to 100%. The fate of islet grafts is determined by many concurrent phenomena, some of which are common to organ grafts (i.e. rejection), while others are unique to nonvascularized cell transplants, including transplant cell mass and viability, as well as nonspecific inflammation at the site of implant. Moreover, islet grafts lack clinical markers of early rejection, making it difficult to recognize imminent rejection and to implement intervention with graft-saving immunosuppressive regimens. In the present review, we will address the problems influencing islet graft success and the monitoring of islet cell graft function.
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Affiliation(s)
- A Pileggi
- Diabetes Research Institute, Cell Transplantation Center, University of Miami School of Medicine, Miami, FL 33136, USA.
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Buijs RM, Chun SJ, Niijima A, Romijn HJ, Nagai K. Parasympathetic and sympathetic control of the pancreas: a role for the suprachiasmatic nucleus and other hypothalamic centers that are involved in the regulation of food intake. J Comp Neurol 2001; 431:405-23. [PMID: 11223811 DOI: 10.1002/1096-9861(20010319)431:4<405::aid-cne1079>3.0.co;2-d] [Citation(s) in RCA: 236] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
To reveal brain regions and transmitter systems involved in control of pancreatic hormone secretion, specific vagal and sympathetic denervation were combined with injection of a retrograde transsynaptic tracer, pseudorabies virus (PRV), into the pancreas. After sympathetic or vagal transsection first-order neurons were revealed in the dorsal motor nucleus of the vagus (DMV) or in preganglionic spinal cord neurons (SPN), respectively. Careful timing of the survival of the animals allowed the detection of cell groups in immediate control of these DMV or SPN neurons. A far larger number of cell groups is involved in the control of DMV than of SPN neurons. Examples are given of a high level of interaction between the sympathetic and parasympathetic nervous system. Several cell groups project to both branches of the autonomic nervous system, sometimes even the same neurotransmitter is used, e.g., oxytocin neurons in the paraventricular nucleus and melanin-concentrating hormone and orexin neurons in the lateral hypothalamus project to both the DMV and SPN neurons. Moreover, the appearance of third-order neurons located in the sympathetic SPN after complete sympathectomy and in the DMV after complete vagotomy illustrates the possibility that motor neurons of the sympathetic and parasympathetic system may exchange information by means of interneurons. The presence of second-order neurons in prefrontal, gustatory, and piriform cortex may provide an anatomic basis for the involvement of these cortices in the cephalic insulin response. The observation that second-order neurons in both vagal and sympathetic control of the pancreas contain neuropeptides that are known to play a role in food intake indicates a direct association between behavioral and autonomic functions. Finally, the observation of third-order neurons in the suprachiasmatic nucleus and ventromedial hypothalamus shows the modulatory action of the time of the day and metabolic state, respectively.
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Affiliation(s)
- R M Buijs
- Netherlands Institute for Brain Research, Meibergdreef 33, Amsterdam 1105 AZ, The Netherlands.
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Nederkoorn C, Smulders FT, Jansen A. Cephalic phase responses, craving and food intake in normal subjects. Appetite 2000; 35:45-55. [PMID: 10896760 DOI: 10.1006/appe.2000.0328] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cephalic phase responses (CPRs) are elicited during exposure to food cues. They gear up the body to optimize digestion or they compensate for unwanted changes during a meal. The cue reactivity model of binge eating predicts that CPRs are experienced as craving for food, thereby increasing food intake and playing a role in abnormal eating behaviour. The present experiment was designed to measure CPRs in normal women and to examine its relationship with craving, food intake and restraint. Results show that normal subjects do react to food exposure with changes in heart rate, heart rate variability (HRV), salivation, blood pressure, skin conductance and gastric activity. These CPRs presumably gear up the body and presumably do not reflect compensatory responses. Significant correlations between restraint and blood pressure, between blood pressure and craving, and between craving and food intake were also found. These results are in line with the cue reactivity model and suggest that research into physiological CPRs and craving in the field of eating disorders is valuable.
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Affiliation(s)
- C Nederkoorn
- Department of Experimental Psychology, Maastricht University, The Netherlands.
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Abstract
Cephalic phase hormonal release occurs through activation of vagal-efferent fibers in response to food-related sensory stimuli. Thus, tasting, chewing and expectorating food elicits hormonal release prior to nutrient absorption. Differential sensitivity of cell types within the islet to neural activation determines the profile and magnitude of hormonal release. While the magnitude of cephalic phase insulin release is relatively small (25% above baseline), pancreatic polypeptide, a hormone almost exclusively under vagal control increases 100% above baseline when individuals taste, chew and expectorate food. Thus, the cephalic phase pancreatic polypeptide response is a sensitive indicator of vagal activation to food stimuli. The physiological significance of the cephalic phase hormonal responses is demonstrated by experimental manipulations which inhibit or bypass cephalic phase insulin release. Under these circumstances, hyperglycemia and hyperinsulinemia are evident. Conversely, supplementation of insulin during the preabsorptive time period improves glucose tolerance in certain clinical populations. These data suggest that cephalic phase insulin release plays a role in glucose homeostasis.
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Affiliation(s)
- K Teff
- Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA
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Babazono T, Teraoka S, Tomonaga O, Iwamoto Y, Omori Y. Circulating proinsulin levels in insulin-dependent diabetic patients after whole pancreas-kidney transplantation. Metabolism 1998; 47:1325-30. [PMID: 9826207 DOI: 10.1016/s0026-0495(98)90299-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Disproportional hyperproinsulinemia is a sensitive marker for beta-cell dysfunction. The objective of this study was to assess the proinsulin profile in persons with insulin-dependent diabetes mellitus (IDDM) after pancreas-kidney transplantation. We determined serum insulin, C-peptide, and proinsulin concentrations during an oral glucose challenge in five pancreas-kidney transplant recipients, nine nondiabetic kidney transplant recipients, and 17 normal subjects. Basal proinsulin concentrations were significantly increased in pancreas-kidney recipients (geometric mean [+/-1 SE range], 6.0 [5.5 to 6.4] pmol/L) and kidney recipients (6.4 [5.4 to 7.5] pmol/L) compared with the normal subjects (2.8 [2.5 to 3.2] pmol/L). Integrated proinsulin concentrations during the oral glucose load were also higher in pancreas-kidney recipients (1.4 [1.1 to 1.8] nmol/L x min) and kidney recipients (1.5 [1.2 to 2.0] nmol/L x min) versus normal subjects (0.8 [0.7 to 0.9] nmol/L x min). There was no difference in basal or integrated proinsulin concentrations between the two transplant groups. Even after adjustment for the glomerular filtration rate (GFR), basal and incremental proinsulin concentrations continued to be higher in the transplant groups than in the normal subjects. Proinsulin to C-peptide molar ratios both before and after the glucose load were similar in the three groups. From these findings, we conclude that pancreas-kidney transplantation provokes proportional hyperproinsulinemia, which is closely associated with its reduced clearance in the kidneys.
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Affiliation(s)
- T Babazono
- Department of Medicine, Diabetes Center, Tokyo Women's Medical College, Japan
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