1
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Borgmann D, Fenselau H. Vagal pathways for systemic regulation of glucose metabolism. Semin Cell Dev Biol 2024; 156:244-252. [PMID: 37500301 DOI: 10.1016/j.semcdb.2023.07.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 06/20/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023]
Abstract
Maintaining blood glucose at an appropriate physiological level requires precise coordination of multiple organs and tissues. The vagus nerve bidirectionally connects the central nervous system with peripheral organs crucial to glucose mobilization, nutrient storage, and food absorption, thereby presenting a key pathway for the central control of blood glucose levels. However, the precise mechanisms by which vagal populations that target discrete tissues participate in glucoregulation are much less clear. Here we review recent advances unraveling the cellular identity, neuroanatomical organization, and functional contributions of both vagal efferents and vagal afferents in the control of systemic glucose metabolism. We focus on their involvement in relaying glucoregulatory cues from the brain to peripheral tissues, particularly the pancreatic islet, and by sensing and transmitting incoming signals from ingested food to the brain. These recent findings - largely driven by advances in viral approaches, RNA sequencing, and cell-type selective manipulations and tracings - have begun to clarify the precise vagal neuron populations involved in the central coordination of glucose levels, and raise interesting new possibilities for the treatment of glucose metabolism disorders such as diabetes.
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Affiliation(s)
- Diba Borgmann
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Physical Activity Research (CFAS), Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Henning Fenselau
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50937 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Straße 26, Cologne 50931, Germany.
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2
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Jimenez-Gonzalez M, Li R, Pomeranz LE, Alvarsson A, Marongiu R, Hampton RF, Kaplitt MG, Vasavada RC, Schwartz GJ, Stanley SA. Mapping and targeted viral activation of pancreatic nerves in mice reveal their roles in the regulation of glucose metabolism. Nat Biomed Eng 2022; 6:1298-1316. [PMID: 35835995 PMCID: PMC9669304 DOI: 10.1038/s41551-022-00909-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 06/09/2022] [Indexed: 11/09/2022]
Abstract
A lack of comprehensive mapping of ganglionic inputs into the pancreas and of technology for the modulation of the activity of specific pancreatic nerves has hindered the study of how they regulate metabolic processes. Here we show that the pancreas-innervating neurons in sympathetic, parasympathetic and sensory ganglia can be mapped in detail by using tissue clearing and retrograde tracing (the tracing of neural connections from the synapse to the cell body), and that genetic payloads can be delivered via intrapancreatic injection to target sites in efferent pancreatic nerves in live mice through optimized adeno-associated viruses and neural-tissue-specific promoters. We also show that, in male mice, the targeted activation of parasympathetic cholinergic intrapancreatic ganglia and neurons doubled plasma-insulin levels and improved glucose tolerance, and that tolerance was impaired by stimulating pancreas-projecting sympathetic neurons. The ability to map the peripheral ganglia innervating the pancreas and to deliver transgenes to specific pancreas-projecting neurons will facilitate the examination of ganglionic inputs and the study of the roles of pancreatic efferent innervation in glucose metabolism.
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Affiliation(s)
- M Jimenez-Gonzalez
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - R Li
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - L E Pomeranz
- Laboratory of Molecular Genetics, The Rockefeller University, New York, NY, USA
| | - A Alvarsson
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - R Marongiu
- Laboratory of Molecular Neurosurgery, Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, USA
| | - R F Hampton
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - M G Kaplitt
- Laboratory of Molecular Neurosurgery, Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, USA
| | - R C Vasavada
- Department of Translational Research and Cellular Therapeutics, City of Hope, Duarte, CA, USA
| | - G J Schwartz
- Departments of Medicine and Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - S A Stanley
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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3
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Payne SC, Ward G, Fallon JB, Hyakumura T, Prins JB, Andrikopoulos S, MacIsaac RJ, Villalobos J. Blood glucose modulation and safety of efferent vagus nerve stimulation in a type 2 diabetic rat model. Physiol Rep 2022; 10:e15257. [PMID: 35439355 PMCID: PMC9017977 DOI: 10.14814/phy2.15257] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 12/21/2022] Open
Abstract
Vagus nerve stimulation is emerging as a promising treatment for type 2 diabetes. Here, we evaluated the ability of stimulation of the vagus nerve to reduce glycemia in awake, freely moving metabolically compromised rats. A model of type 2 diabetes (n = 10) was induced using a high‐fat diet and low doses of streptozotocin. Stimulation of the abdominal vagus nerve was achieved by pairing 15 Hz pulses on a distal pair of electrodes with high‐frequency blocking stimulation (26 kHz, 4 mA) on a proximal pair of electrodes to preferentially produce efferent conducting activity (eVNS). Stimulation was well tolerated in awake, freely moving rats. During 1 h of eVNS, glycemia decreased in 90% of subjects (−1.25 ± 1.25 mM h, p = 0.017), and 2 dB above neural threshold was established as the most effective “dose” of eVNS (p = 0.009). Following 5 weeks of implantation, eVNS was still effective, resulting in significantly decreased glycemia (−1.7 ± 0.6 mM h, p = 0.003) during 1 h of eVNS. There were no overt changes in fascicle area or signs of histopathological damage observed in implanted vagal nerve tissue following chronic implantation and stimulation. Demonstration of the biocompatibility and safety of eVNS in awake, metabolically compromised animals is a critical first step to establishing this therapy for clinical use. With further development, eVNS could be a promising novel therapy for treating type 2 diabetes.
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Affiliation(s)
- Sophie C Payne
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Medical Bionics, University of Melbourne, Parkville, Victoria, Australia
| | - Glenn Ward
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia.,Melbourne Medical School, University of Melbourne, Parkville, Victoria, Australia
| | - James B Fallon
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Medical Bionics, University of Melbourne, Parkville, Victoria, Australia
| | - Tomoko Hyakumura
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Medical Bionics, University of Melbourne, Parkville, Victoria, Australia
| | - Johannes B Prins
- Melbourne Medical School, University of Melbourne, Parkville, Victoria, Australia.,Department of Endocrinology, Royal Melbourne Hospital, Parkville, Victoria, Australia.,Australian Centre for Accelerating Diabetes Innovations, University of Melbourne, Melbourne, Australia
| | - Sofianos Andrikopoulos
- Australian Centre for Accelerating Diabetes Innovations, University of Melbourne, Melbourne, Australia.,Department of Medicine (Austin Health), University of Melbourne, Heidelberg, Victoria, Australia
| | - Richard J MacIsaac
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia.,Melbourne Medical School, University of Melbourne, Parkville, Victoria, Australia.,Australian Centre for Accelerating Diabetes Innovations, University of Melbourne, Melbourne, Australia
| | - Joel Villalobos
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Medical Bionics, University of Melbourne, Parkville, Victoria, Australia
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4
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Wakiya T, Ishido K, Yoshizawa T, Kanda T, Hakamada K. Roles of the nervous system in pancreatic cancer. Ann Gastroenterol Surg 2021; 5:623-633. [PMID: 34585047 PMCID: PMC8452481 DOI: 10.1002/ags3.12459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/04/2021] [Accepted: 03/14/2021] [Indexed: 12/24/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC), with its extremely poor prognosis, presents a substantial health problem worldwide. Outcomes have improved thanks to progress in surgical technique, chemotherapy, pre-/postoperative management, and centralization of patient care to high-volume centers. However, our goals are yet to be met. Recently, exome sequencing using PDAC surgical specimens has demonstrated that the most frequently altered genes were the axon guidance genes, indicating involvement of the nervous system in PDAC carcinogenesis. Moreover, perineural invasion has been widely identified as one poor prognostic factor. The combination of innovative technologies and extensive clinician experience with the nervous system come together here to create a new treatment option. However, evidence has emerged that suggests that the relationship between cancer and nerves in PDAC, the underlying mechanism, is not fully understood. In an attempt to tackle this lethal cancer, this review summarizes the anatomy and physiology of the pancreas and discusses the role of the nervous system in the pathophysiology of PDAC.
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Affiliation(s)
- Taiichi Wakiya
- Department of Gastroenterological SurgeryHirosaki University Graduate School of MedicineHirosakiJapan
| | - Keinosuke Ishido
- Department of Gastroenterological SurgeryHirosaki University Graduate School of MedicineHirosakiJapan
| | - Tadashi Yoshizawa
- Department of Pathology and BioscienceHirosaki University Graduate School of MedicineHirosakiJapan
| | - Taishu Kanda
- Department of Gastroenterological SurgeryHirosaki University Graduate School of MedicineHirosakiJapan
| | - Kenichi Hakamada
- Department of Gastroenterological SurgeryHirosaki University Graduate School of MedicineHirosakiJapan
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Payne SC, Ward G, MacIsaac RJ, Hyakumura T, Fallon JB, Villalobos J. Differential effects of vagus nerve stimulation strategies on glycemia and pancreatic secretions. Physiol Rep 2020; 8:e14479. [PMID: 32512650 PMCID: PMC7280012 DOI: 10.14814/phy2.14479] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/15/2020] [Accepted: 05/15/2020] [Indexed: 12/14/2022] Open
Abstract
Despite advancements in pharmacotherapies, glycemia is poorly controlled in type 2 diabetic patients. As the vagus nerve regulates energy metabolism, here we evaluated the effect various electrical vagus nerve stimulation strategies have on glycemia and glucose-regulating hormones, as a first step to developing a novel therapy of type 2 diabetes. Sprague-Dawley rats were anesthetized, the abdominal (anterior) vagus nerve implanted, and various stimulation strategies applied to the nerve: (a) 15 Hz; (b) 4 kHz, or 40 kHz and; (c) a combination of 15 Hz and 40 kHz to directionally activate afferent or efferent vagal fibers. Following a glucose bolus (500 mg/kg, I.V.), stimulation strategies were applied (60 min) and serial blood samples taken. No stimulation was used as a crossover control sequence. Applying 15 Hz stimulation significantly increased glucose (+2.9 ± 0.2 mM·hr, p = .015) and glucagon (+17.1 ± 8.0 pg·hr/ml, p = .022), compared to no stimulation. Application of 4 kHz stimulation also significantly increased glucose levels (+1.5 ± 0.5 mM·hr, p = .049), while 40 kHz frequency stimulation resulted in no changes to glucose levels but did significantly lower glucagon (-12.3 ± 1.1 pg·hr/ml, p = .0009). Directional afferent stimulation increased glucose (+2.4 ± 1.5 mM·hr) and glucagon levels (+39.5 ± 15.0 pg·hr/ml). Despite hyperglycemia resulting when VNS, aVNS, and 4 kHz stimulation strategies were applied, the changes in insulin levels were not significant (p ≥ .05). In summary, vagus nerve stimulation modulates glycemia by effecting glucagon and insulin secretions, and high-frequency 40 kHz stimulation may have potential application for the treatment of type 2 diabetes.
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Affiliation(s)
- Sophie C. Payne
- Bionics InstituteEast MelbourneVic.Australia
- Medical Bionics DepartmentThe University of MelbourneParkvilleVic.Australia
| | - Glenn Ward
- Bionics InstituteEast MelbourneVic.Australia
- Department of Endocrinology and DiabetesSt Vincent’s HospitalFitzroyVic.Australia
- Department of MedicineThe University of MelbourneParkvilleVic.Australia
| | - Richard J. MacIsaac
- Bionics InstituteEast MelbourneVic.Australia
- Department of Endocrinology and DiabetesSt Vincent’s HospitalFitzroyVic.Australia
- Department of MedicineThe University of MelbourneParkvilleVic.Australia
| | - Tomoko Hyakumura
- Bionics InstituteEast MelbourneVic.Australia
- Medical Bionics DepartmentThe University of MelbourneParkvilleVic.Australia
| | - James B. Fallon
- Bionics InstituteEast MelbourneVic.Australia
- Medical Bionics DepartmentThe University of MelbourneParkvilleVic.Australia
| | - Joel Villalobos
- Bionics InstituteEast MelbourneVic.Australia
- Medical Bionics DepartmentThe University of MelbourneParkvilleVic.Australia
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Reis MB, Elias-Oliveira J, Pastore MR, Ramos SG, Gardinassi LG, Faccioli LH. Interleukin-1 Receptor-Induced Nitric Oxide Production in the Pancreas Controls Hyperglycemia Caused by Scorpion Envenomation. Toxins (Basel) 2020; 12:toxins12030163. [PMID: 32150895 PMCID: PMC7150851 DOI: 10.3390/toxins12030163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 12/14/2022] Open
Abstract
Tityus serrulatus causes numerous scorpion envenomation accidents and deaths worldwide. The symptoms vary from local to systemic manifestations, culminating in pulmonary edema and cardiogenic shock. Among these events, transitory hyperglycemia is a severe manifestation that influences pulmonary edema, hemodynamic alterations, and cardiac disturbances. However, the molecular mechanism that leads to increased glucose levels after T. serrulatus envenomation remains unknown. This study aimed to investigate our hypothesis that hyperglycemia due to scorpion envenomation involves inflammatory signaling in the pancreas. The present study showed that T. serrulatus venom induces the production of IL-1α and IL-1β in the pancreas, which signal via IL-1R and provoke nitric oxide (NO) production as well as edema in β-cells in islets. Il1r1−/− mice were protected from transitory hyperglycemia and did not present disturbances in insulin levels in the serum. These results suggest that the pathway driven by IL-1α/IL-1β-IL-1R-NO inhibits insulin release by β-cells, which increases systemic glucose concentration during severe scorpion envenomation. A supportive therapy that inhibits NO production, combined with antiserum, may help to prevent fatal outcomes of scorpion envenomation. Our findings provide novel insights into the design of supportive therapy with NO inhibitors combined with antiscorpion venom serum to overcome fatal outcomes of scorpion envenomation.
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Affiliation(s)
- Mouzarllem B. Reis
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo 14040-903, Brazil; (M.B.R.); (J.E.-O.); (M.R.P.); (L.G.G.)
| | - Jefferson Elias-Oliveira
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo 14040-903, Brazil; (M.B.R.); (J.E.-O.); (M.R.P.); (L.G.G.)
| | - Marcella R. Pastore
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo 14040-903, Brazil; (M.B.R.); (J.E.-O.); (M.R.P.); (L.G.G.)
| | - Simone G. Ramos
- Departamento de Patologia e Medicina Legal, Faculdade de Medicina de Ribeirão Preto, São Paulo 14049-900, Brazil;
| | - Luiz G. Gardinassi
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo 14040-903, Brazil; (M.B.R.); (J.E.-O.); (M.R.P.); (L.G.G.)
| | - Lúcia H. Faccioli
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo 14040-903, Brazil; (M.B.R.); (J.E.-O.); (M.R.P.); (L.G.G.)
- Correspondence:
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7
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Güemes A, Herrero P, Bondia J, Georgiou P. Modeling the effect of the cephalic phase of insulin secretion on glucose metabolism. Med Biol Eng Comput 2019; 57:1173-1186. [PMID: 30685858 PMCID: PMC6525153 DOI: 10.1007/s11517-019-01950-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 01/07/2019] [Indexed: 02/05/2023]
Abstract
The nervous system has a significant impact in glucose homeostasis and endocrine pancreatic secretion in humans, especially during the cephalic phase of insulin release (CPIR); that is, before a meal is absorbed. However, the underlying mechanisms of this neural-pancreatic interaction are not well understood and therefore often neglected, despite their significance to achieving an optimal glucose control. As a result, the dynamics of insulin release from the pancreas are currently described by mathematical models that reproduce the behavior of the β cells using exclusively glucose levels and other hormones as inputs. To bridge this gap, we have combined, for the first time, metabolic and neural mathematical models in a unified system to reproduce to a great extent the ideal glucoregulation observed in healthy subjects. Our results satisfactorily replicate the CPIR and its impact during the post-absorptive phase. Furthermore, the proposed model gives insight into the physiological interaction between the brain and the pancreas in healthy people and suggests the potential of considering the neural information for restoring glucose control in people with diabetes. Graphical Abstract (a) Physiological scenario. Diagram of the biological interaction among the most important organs involved in glucose control during meal intake. (b) Scheme of the unified bio-inspired neural-metabolic model. Each of the boxes represents one subsystem of the model. The pink shades boxes depicts the novel subsystems introduced to the current metabolic models (grey shaded boxes). Insulin-related action and mass fluxes (solid black lines) and glucose-related action and mass flux (dotted black lines) are depicted to show the relationship among the blocks. I(t), Ic(t), G(t) and SI related to plasma insulin, plasma cephalic insulin, plasma glucose and insulin sensitivity, respectively.
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Affiliation(s)
- Amparo Güemes
- Centre for Bio-Inspired Technology, Department of Electrical and Electronic Engineering, Imperial College London, South Kensington Campus, London, UK.
| | - Pau Herrero
- Centre for Bio-Inspired Technology, Department of Electrical and Electronic Engineering, Imperial College London, South Kensington Campus, London, UK
| | - Jorge Bondia
- Instituto Universitario de Automática e Informática Industrial, Universitat Politècnica de València, Valencia, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Pantelis Georgiou
- Centre for Bio-Inspired Technology, Department of Electrical and Electronic Engineering, Imperial College London, South Kensington Campus, London, UK
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8
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Meyers EE, Kronemberger A, Lira V, Rahmouni K, Stauss HM. Contrasting effects of afferent and efferent vagal nerve stimulation on insulin secretion and blood glucose regulation. Physiol Rep 2016; 4:e12718. [PMID: 26884478 PMCID: PMC4759047 DOI: 10.14814/phy2.12718] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 11/24/2022] Open
Abstract
Parasympathetic activation reduces hepatic glucose release and increases pancreatic insulin secretion in hyperglycemic conditions. Thus, vagal nerve stimulation (VNS) may potentially be effective in treating type II diabetes. To investigate this possibility, we hypothesized that VNS reduces blood glucose concentration [Glu] via insulin secretion. [Glu] together with insulin and glucagon serum concentrations were determined in anesthetized rats during baseline conditions and 120 min of cervical VNS with the nerve left intact for combined afferent and efferent VNS (n = 9) or the nerve sectioned proximal or distal from the stimulation electrode for selective efferent (n = 8) or afferent (n = 7) VNS, respectively. Afferent VNS caused a strong and sustained increase in [Glu] (+108.9 ± 20.9% or +77.6 ± 15.4%, after 120 min of combined afferent and efferent VNS or selective afferent VNS) that was not accompanied by an increase in serum insulin concentration. However, serum insulin levels increased significantly with selective efferent VNS (+71.2 ± 27.0% after 120 min of VNS) that increased [Glu] only temporarily (+28.8 ± 11.7% at 30 min of VNS). Efferent VNS initially increased serum glucagon concentration which remained elevated for 120 min when efferent VNS was combined with afferent VNS, but returned to baseline with selective efferent VNS. These findings demonstrate that afferent VNS causes a marked and sustained increase in [Glu] that is partly mediated by suppression of pancreatic insulin secretion. In contrast, efferent VNS stimulates pancreatic glucagon secretion that appears to be antagonized by insulin secretion in the case of selective efferent VNS. Selective efferent VNS may potentially be effective in treating type II diabetes.
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Affiliation(s)
- Erin E Meyers
- Department of Health and Human Physiology, The University of Iowa, Iowa City, Iowa
| | - Ana Kronemberger
- Department of Health and Human Physiology, The University of Iowa, Iowa City, Iowa
| | - Vitor Lira
- Department of Health and Human Physiology, The University of Iowa, Iowa City, Iowa
| | - Kamal Rahmouni
- Department of Pharmacology, The University of Iowa, Iowa City, Iowa
| | - Harald M Stauss
- Department of Health and Human Physiology, The University of Iowa, Iowa City, Iowa
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10
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Gilon P, Henquin JC. Mechanisms and physiological significance of the cholinergic control of pancreatic beta-cell function. Endocr Rev 2001; 22:565-604. [PMID: 11588141 DOI: 10.1210/edrv.22.5.0440] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Acetylcholine (ACh), the major parasympathetic neurotransmitter, is released by intrapancreatic nerve endings during the preabsorptive and absorptive phases of feeding. In beta-cells, ACh binds to muscarinic M(3) receptors and exerts complex effects, which culminate in an increase of glucose (nutrient)-induced insulin secretion. Activation of PLC generates diacylglycerol. Activation of PLA(2) produces arachidonic acid and lysophosphatidylcholine. These phospholipid-derived messengers, particularly diacylglycerol, activate PKC, thereby increasing the efficiency of free cytosolic Ca(2+) concentration ([Ca(2+)](c)) on exocytosis of insulin granules. IP3, also produced by PLC, causes a rapid elevation of [Ca(2+)](c) by mobilizing Ca(2+) from the endoplasmic reticulum; the resulting fall in Ca(2+) in the organelle produces a small capacitative Ca(2+) entry. ACh also depolarizes the plasma membrane of beta-cells by a Na(+)- dependent mechanism. When the plasma membrane is already depolarized by secretagogues such as glucose, this additional depolarization induces a sustained increase in [Ca(2+)](c). Surprisingly, ACh can also inhibit voltage-dependent Ca(2+) channels and stimulate Ca(2+) efflux when [Ca(2+)](c) is elevated. However, under physiological conditions, the net effect of ACh on [Ca(2+)](c) is always positive. The insulinotropic effect of ACh results from two mechanisms: one involves a rise in [Ca(2+)](c) and the other involves a marked, PKC-mediated increase in the efficiency of Ca(2+) on exocytosis. The paper also discusses the mechanisms explaining the glucose dependence of the effects of ACh on insulin release.
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Affiliation(s)
- P Gilon
- Unité d'Endocrinologie et Métabolisme, University of Louvain Faculty of Medicine, B-1200 Brussels, Belgium.
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11
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Brunicardi FC, Shavelle DM, Andersen DK. Neural regulation of the endocrine pancreas. INTERNATIONAL JOURNAL OF PANCREATOLOGY : OFFICIAL JOURNAL OF THE INTERNATIONAL ASSOCIATION OF PANCREATOLOGY 1995; 18:177-95. [PMID: 8708389 DOI: 10.1007/bf02784941] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- F C Brunicardi
- Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA
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12
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Dunning BE, Taborsky GJ. Neural control of islet function by norepinephrine and sympathetic neuropeptides. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 291:107-27. [PMID: 1927679 DOI: 10.1007/978-1-4684-5931-9_10] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
It is clear that the sympathoadrenal system has a role in the regulation of endocrine pancreatic function and that the sympathetic nerves of the pancreas can change pancreatic hormone secretion to increase the availability of metabolic fuels. It seems likely that the classical sympathetic neurotransmitter, NE, acts in concert with peptide co-transmitters, such as galanin and NPY. Each is released during the stimulation of pancreatic sympathetic nerves and each is capable of influencing either islet function or pancreatic blood flow. There is considerable indirect evidence that the sympathetic innervation of the pancreas is activated during acute stress and influences the endocrine pancreas. However, proving such a physiologic role is difficult because of redundant mechanisms that influence the secretion of the metabolically-crucial hormones, insulin and glucagon. Such definitive proof therefore awaits the development of new techniques to dissect and dissociate these mechanisms.
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Affiliation(s)
- B E Dunning
- Diabetes Depart, Sandoz Research Institute, East Hanover, NJ 07936
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13
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Kurose T, Seino Y, Nishi S, Tsuji K, Taminato T, Tsuda K, Imura H. Mechanism of sympathetic neural regulation of insulin, somatostatin, and glucagon secretion. THE AMERICAN JOURNAL OF PHYSIOLOGY 1990; 258:E220-7. [PMID: 1689116 DOI: 10.1152/ajpendo.1990.258.1.e220] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effects of electrical stimulation of the left splanchnic nerve on insulin, somatostatin, and glucagon secretion from the isolated perfused rat pancreas were investigated. Electrical splanchnic nerve stimulation (SNS), performed by square-wave impulses, produced a 25% decrease in effluent flow and a 10-fold increase in perfusate norepinephrine. Both insulin and somatostatin output in the presence of 16.7 mM glucose were inhibited during SNS by 85 and 56% of the basal value, respectively. Glucagon output in the presence of 5.5 mM glucose was stimulated 20-fold by SNS. Perfusion with 10(-6) M propranolol further decreased insulin and somatostatin output during SNS, when expressed as the total decrement beneath basal during stimulation. The glucagon response to SNS tended to be enhanced, although not significantly, by simultaneous infusion of 10(-6) M propranolol. However, 10(-6) M phentolamine (Phe) attenuated the SNS-induced inhibition of insulin and somatostatin output by 50 and 40%, respectively. However, insulin output remained decreased after SNS with Phe. The SNS-induced glucagon response was completely abolished by 10(-6) M Phe alone or by 10(-6) M Phe plus 10(-6) M propranolol. With 10(-6) M Phe plus 10(-6) M propranolol, insulin and somatostatin output remained decreased after SNS. These results suggest that insulin and somatostatin secretions induced by glucose are inhibited during SNS through the alpha-adrenergic mechanism and also that the beta-adrenergic mechanism exerts a stimulatory action. SNS-induced glucagon secretion occurs mainly through alpha-adrenergic activation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Kurose
- Department of Medicine, Kyoto University School of Medicine, Japan
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Dunning BE, Ahrén B, Veith RC, Taborsky GJ. Nonadrenergic sympathetic neural influences on basal pancreatic hormone secretion. THE AMERICAN JOURNAL OF PHYSIOLOGY 1988; 255:E785-92. [PMID: 2904765 DOI: 10.1152/ajpendo.1988.255.6.e785] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Evidence for peptidergic innervation of the islets of Langerhans is increasing, yet the role of neuropeptides in mediating neurally induced changes of islet function is not clear. To determine if nonadrenergic transmitters make an important contribution to sympathetic neural effects on basal pancreatic hormone secretion, we examined the effect of local sympathetic nerve stimulation (SNS) on the output of immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and somatostatin (SLI) from the duodenal lobe of the pancreas in situ in halothane-anesthetized dogs, under conditions where the actions of the classical transmitter norepinephrine (NE) should be blocked by propranolol (PROP) and yohimbine (YO). In the absence of adrenergic antagonists, SNS rapidly reduced the output of IRI (delta = -1.34 +/- 0.91 mU/min) and SLI (delta = -600 +/- 350 fmol/min) and stimulated that of IRG (delta = +1.39 +/- 0.57 ng/min). In the presence of PROP and YO, SNS induced similar changes of hormone secretion: delta IRI, -1.30 +/- 0.53 mU/min; delta SLI, -480 +/- 180 fmol/min; delta IRG = +1.89 +/- 0.63 ng/min. Because PROP and YO abolished the pancreatic effects of high dose infusions of NE (1 microgram.kg-1.min-1 iv), we suggest that the antagonists produced sufficient, combined adrenergic blockade at the level of the islet, and we conclude that a nonadrenergic neurotransmitter or modulator plays a major role in mediating sympathetic neural effects on basal islet hormone secretion.
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Affiliation(s)
- B E Dunning
- Division of Endocrinology and Metabolism, Veterans Administration Medical Center, Seattle, Washington
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Schulz A, Hasselblatt A. Phentolamine, a deceptive tool to investigate sympathetic nervous control of insulin release. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1988; 337:637-43. [PMID: 3063970 DOI: 10.1007/bf00175789] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We investigated the effects of phentolamine and another more selective alpha 2-adrenoceptor antagonist, rauwolscine, on insulin release in vivo (in female Wistar-rats) and in vitro (in perfused rat pancreas and in isolated perifused mouse islets). Phentolamine was found to significantly increase glucose-induced insulin release. On the other hand, rauwolscine failed to do so, when applied in a concentration that effectively antagonized the inhibitory effect of clonidine. These results demonstrate that phentolamine is capable of directly stimulating insulin release. This effect is thus not mediated by alpha-adrenoceptors. For this reason phentolamine is not an appropriate tool to study possible inhibitory effects of the sympathetic nervous system on insulin release. An enhanced insulin response as may be observed in animals and in man in the presence of phentolamine does not furnish evidence for a tonic inhibitory control of the islet cells by the sympathetic nervous system.
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Affiliation(s)
- A Schulz
- Institut für Pharmakologie und Toxikologie, Universität Göttingen, Federal Republic of Germany
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Dunning BE, Ahren B, Böttcher G, Sundler F, Taborsky GJ. The presence and actions of NPY in the canine endocrine pancreas. REGULATORY PEPTIDES 1987; 18:253-65. [PMID: 2890183 DOI: 10.1016/0167-0115(87)90183-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Immunofluorescent staining for neuropeptide Y (NPY) in canine pancreatic tissue was performed together with an evaluation of the effects of synthetic NPY on the release of insulin (IRI), glucagon (IRG) and somatostatin (SLI) from the duodenal lobe of the canine pancreas in situ. NPY-like immunoreactivity was localized in perivascular nerve fibers throughout the acinar tissue. NPY-immunoreactive fibers were also demonstrated in the islets, usually surrounding blood vessels but also occasionally in fibers associated with endocrine cells, primarily at the periphery of islets. In addition, the ganglia dispersed in the pancreatic parenchyma were densely innervated by NPY-immunoreactive fibers, and these ganglia regularly contained cell bodies staining for NPY. Direct infusion of NPY into the pancreatic artery (p.a.) produced a dose-dependent decrease of pancreatic SLI output and of pancreatic venous blood flow. Low-dose p.a. infusion of NPY (50 pmol/min) had no effect on basal IRI or IRG output or on the islet response to glucose (5-g bolus, i.v.). High-dose p.a. infusion of NPY (500 pmol/min) transiently stimulated IRI output and modestly increased IRG output. However, the comparatively sparse innervation of canine islets with NPY-like immunoreactive fibers and the relatively minor effects of large doses of synthetic NPY on pancreatic hormone release lead us to conclude that this peptide is not an important neuromodulator of islet function in the dog.
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Affiliation(s)
- B E Dunning
- Division of Endocrinology and Metabolism, Veterans Administration Medical Center, Seattle, WA 98108
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Berrios GE, Bulbena A, Martinez AR, Ortega Gazo D, Castellanos Llorens JM, Lozano CD. Significant rise in plasma insulin after electroconvulsive therapy. Acta Psychiatr Scand 1986; 74:222-4. [PMID: 3535384 DOI: 10.1111/j.1600-0447.1986.tb10610.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The effect of ECT on insulin plasma levels was studied in 10 single treatments in five patients suffering from DSM III-diagnosed schizophrenia. The treatments were chosen from early, middle and late ordinal positions. A significant rise was found 10, 20 and 30 min after an effective electrical stimulus. Values returned to normal in all cases at 60 min. The rise at 10 min occurred in all treatments, irrespective of ordinal position, but an incidental finding was that the higher the ordinal position of a given treatment, the higher the peak of insulin.
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Ahrén B, Lundquist I. Effects of alpha-adrenoceptor blockade by phentolamine on basal and stimulated insulin secretion in the mouse. ACTA PHYSIOLOGICA SCANDINAVICA 1985; 125:211-7. [PMID: 2866660 DOI: 10.1111/j.1748-1716.1985.tb07709.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The sympathetic nervous system is known to innervate the pancreatic islets and to have the capability to influence islet hormone release. The effects are, however, complex since the islet nerves contain catecholaminergic as well as peptidergic fibres, and the catecholamines stimulate alpha- as well as beta-adrenoceptors. The present study was undertaken to establish the possible influence of the alpha-adrenoceptors on basal and stimulated insulin secretion under in vivo conditions. The alpha-adrenoceptor blocker phentolamine was injected at various dose levels i.p. to mice and a dose-dependent increase in plasma concentrations of insulin was seen. The maximal plasma insulin levels were observed 10 min after injection and were accompanied by decreased plasma glucose concentrations. Additionally, plasma glucose levels fell in response to phentolamine by an apparent insulin-independent manner, since at the low dose of 2.6 mumol kg-1, plasma glucose levels did decrease without any apparent increase in plasma insulin levels. After injection of a low dose of phentolamine 10 min prior to a rapid i.v. injection of one of four different insulin secretagogues, the following effects on insulin release were observed. Glucose (+55%) and the cholinergic agonist carbachol (+140%) displayed a potentiated insulin secretory response after phentolamine pretreatment, whereas the beta 2-adrenoceptor agonist terbutaline (-45%) had a blunted, though not abolished, insulin response. The absolute insulin secretory response to CCK-8 was unaffected by phentolamine despite the fact that plasma glucose levels were lowered by phentolamine. In conclusion, phentolamine enhanced insulin secretion and depressed plasma glucose levels in mice.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J.J. Holst
- Institute of Medical Physiology Cthe Panum InstituteUniversity of CopenhagenDenmark
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Bloom SR, Edwards AV. Characteristics of the neuroendocrine responses to stimulation of the splanchnic nerves in bursts in the conscious calf. J Physiol 1984; 346:533-45. [PMID: 6366188 PMCID: PMC1199516 DOI: 10.1113/jphysiol.1984.sp015039] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Neuroendocrine responses to splanchnic nerve stimulation in bursts (at 40 Hz for 1 s at 10 s intervals for 10 min) have been investigated in conscious adrenalectomized calves, 3-6 weeks after birth, in the presence of various pharmacological blocking agents. Preganglionic blockade with hexamethonium abolished all the neuroendocrine responses that were monitored. Pre-treatment with phentolamine significantly reduced, but failed to eliminate, the release of both pancreatic glucagon and pancreatic polypeptide. In the presence of phentolamine splanchnic nerve stimulation produced a massive rise in arterial plasma insulin concentration. None of these pancreatic neuroendocrine responses was significantly affected by additional pre-treatment with propranolol. The rise in mean plasma insulin concentration which occurred in calves pre-treated with both phentolamine and propranolol was significantly reduced by atropine. Release of bombesin-like immunoreactivity (BLI) was unaffected by total post-ganglionic adrenergic and cholinergic blockade. The results indicate that pancreatic endocrine responses to splanchnic nerve stimulation may be attributable, at least in part, to release of BLI in this species.
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