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Kajani S, Laker RC, Ratkova E, Will S, Rhodes CJ. Hepatic glucagon action: beyond glucose mobilization. Physiol Rev 2024; 104:1021-1060. [PMID: 38300523 DOI: 10.1152/physrev.00028.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 01/10/2024] [Accepted: 01/11/2024] [Indexed: 02/02/2024] Open
Abstract
Glucagon's ability to promote hepatic glucose production has been known for over a century, with initial observations touting this hormone as a diabetogenic agent. However, glucagon receptor agonism [when balanced with an incretin, including glucagon-like peptide 1 (GLP-1) to dampen glucose excursions] is now being developed as a promising therapeutic target in the treatment of metabolic diseases, like metabolic dysfunction-associated steatotic disease/metabolic dysfunction-associated steatohepatitis (MASLD/MASH), and may also have benefit for obesity and chronic kidney disease. Conventionally regarded as the opposing tag-team partner of the anabolic mediator insulin, glucagon is gradually emerging as more than just a "catabolic hormone." Glucagon action on glucose homeostasis within the liver has been well characterized. However, growing evidence, in part thanks to new and sensitive "omics" technologies, has implicated glucagon as more than just a "glucose liberator." Elucidation of glucagon's capacity to increase fatty acid oxidation while attenuating endogenous lipid synthesis speaks to the dichotomous nature of the hormone. Furthermore, glucagon action is not limited to just glucose homeostasis and lipid metabolism, as traditionally reported. Glucagon plays key regulatory roles in hepatic amino acid and ketone body metabolism, as well as mitochondrial turnover and function, indicating broader glucagon signaling consequences for metabolic homeostasis mediated by the liver. Here we examine the broadening role of glucagon signaling within the hepatocyte and question the current dogma, to appreciate glucagon as more than just that "catabolic hormone."
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Affiliation(s)
- Sarina Kajani
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Rhianna C Laker
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Ekaterina Ratkova
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Mölndal, Sweden
| | - Sarah Will
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Christopher J Rhodes
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
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2
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Trinh B, Rasmussen Rinnov A, Winning Iepsen U, Winding Munch G, Munch Winding K, Lauridsen C, Gluud LL, van Hall G, Ellingsgaard H. Glucose turnover at whole-body and skeletal muscle level in response to parenteral nutrition in male patients with alcoholic liver cirrhosis. Clin Nutr ESPEN 2024; 60:240-246. [PMID: 38479917 DOI: 10.1016/j.clnesp.2024.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/21/2024] [Accepted: 02/09/2024] [Indexed: 04/13/2024]
Abstract
BACKGROUND & AIMS Cirrhosis is associated with insulin resistance and impaired glucose tolerance, which may be caused by impairments at different tissue levels (liver, skeletal muscle, and/or beta cell). METHODS Here, glucose kinetics at whole-body and skeletal muscle level in patients with cirrhosis (Child-Pugh A and B) were studied during parenteral nutrition using the isotope dilution technique and arteriovenous balance approach across the leg. As opposed to the euglycemic hyperinsulinemic clamp or glucose tolerance tests applied in previous studies, this approach provides a nutrient composition more similar to a normal meal while circumventing any possible portal-systemic shunting, impaired hepatic uptake and incretin effect. RESULTS We confirmed the presence of hepatic and peripheral insulin resistance in our patient population. Endogenous glucose production was less suppressed in response to parenteral nutrition. However, glucose uptake in skeletal muscle was increased. CONCLUSION Our results suggests that in our study participants with cirrhosis, the hepatic and peripheral insulin resistance is compensated for by increased insulin secretion and thus, increased glucose uptake in muscle. Hereby, glucose homeostasis is maintained.
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Affiliation(s)
- Beckey Trinh
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark.
| | - Anders Rasmussen Rinnov
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark
| | - Ulrik Winning Iepsen
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark; Department of Anaesthesiology and Intensive Care, Copenhagen University Hospital - Hvidovre Hospital, Copenhagen, Denmark
| | - Gregers Winding Munch
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark
| | - Kamilla Munch Winding
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark
| | - Carsten Lauridsen
- Department of Diagnostic Radiology, Copenhagen University Hospital - Rigshospitalet, Denmark; Department of Technology, Copenhagen University College, Denmark
| | - Lise Lotte Gluud
- Gastrounit, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Clinical Biochemistry, Copenhagen University Hospital, Department of Biomedical Sciences, Health & Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Helga Ellingsgaard
- The Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Denmark
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3
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Gray SM, Goonatilleke E, Emrick MA, Becker JO, Hoofnagle AN, Stefanovski D, He W, Zhang G, Tong J, Campbell J, D’Alessio DA. High Doses of Exogenous Glucagon Stimulate Insulin Secretion and Reduce Insulin Clearance in Healthy Humans. Diabetes 2024; 73:412-425. [PMID: 38015721 PMCID: PMC10882148 DOI: 10.2337/db23-0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 11/20/2023] [Indexed: 11/30/2023]
Abstract
Glucagon is generally defined as a counterregulatory hormone with a primary role to raise blood glucose concentrations by increasing endogenous glucose production (EGP) in response to hypoglycemia. However, glucagon has long been known to stimulate insulin release, and recent preclinical findings have supported a paracrine action of glucagon directly on islet β-cells that augments their secretion. In mice, the insulinotropic effect of glucagon is glucose dependent and not present during basal euglycemia. To test the hypothesis that the relative effects of glucagon on hepatic and islet function also vary with blood glucose, a group of healthy subjects received glucagon (100 ng/kg) during fasting glycemia or experimental hyperglycemia (∼150 mg/dL) on 2 separate days. During fasting euglycemia, administration of glucagon caused blood glucose to rise due to increased EGP, with a delayed increase of insulin secretion. When given during experimental hyperglycemia, glucagon caused a rapid, threefold increase in insulin secretion, as well as a more gradual increase in EGP. Under both conditions, insulin clearance was decreased in response to glucagon infusion. The insulinotropic action of glucagon, which is proportional to the degree of blood glucose elevation, suggests distinct physiologic roles in the fasting and prandial states. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Sarah M. Gray
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Elisha Goonatilleke
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Michelle A. Emrick
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Jessica O. Becker
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Andrew N. Hoofnagle
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
| | - Darko Stefanovski
- Department of Clinical Studies–New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square
| | - Wentao He
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Guofang Zhang
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Jenny Tong
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
- Endocrine Section, VA Puget Sound Health Care System, Seattle
| | - Jonathan Campbell
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC
| | - David A. D’Alessio
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC
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Tomar M, Somvanshi PR, Kareenhalli V. Physiological significance of bistable circuit design in metabolic homeostasis: role of integrated insulin-glucagon signalling network. Mol Biol Rep 2022; 49:5017-5028. [DOI: 10.1007/s11033-022-07175-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 01/19/2022] [Indexed: 10/19/2022]
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Wewer Albrechtsen NJ. The glucose-mobilizing effect of glucagon at fasting is mediated by cyclic AMP. Am J Physiol Endocrinol Metab 2021; 321:E571-E574. [PMID: 34369821 DOI: 10.1152/ajpendo.00172.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Rigshospitalet & Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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6
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Dirnena-Fusini I, Åm MK, Fougner AL, Carlsen SM, Christiansen SC. Physiological effects of intraperitoneal versus subcutaneous insulin infusion in patients with diabetes mellitus type 1: A systematic review and meta-analysis. PLoS One 2021; 16:e0249611. [PMID: 33848314 PMCID: PMC8043377 DOI: 10.1371/journal.pone.0249611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 03/22/2021] [Indexed: 11/18/2022] Open
Abstract
The intraperitoneal route of administration accounts for less than 1% of insulin treatment regimes in patients with diabetes mellitus type 1 (DM1). Despite being used for decades, a systematic review of various physiological effects of this route of insulin administration is lacking. Thus, the aim of this systematic review was to identify the physiological effects of continuous intraperitoneal insulin infusion (CIPII) compared to those of continuous subcutaneous insulin infusion (CSII) in patients with DM1. Four databases (EMBASE, PubMed, Scopus and CENTRAL) were searched beginning from the inception date of each database to 10th of July 2020, using search terms related to intraperitoneal and subcutaneous insulin administration. Only studies comparing CIPII treatment (≥ 1 month) with CSII treatment were included. Primary outcomes were long-term glycaemic control (after ≥ 3 months of CIPII inferred from glycated haemoglobin (HbA1c) levels) and short-term (≥ 1 day for each intervention) measurements of insulin dynamics in the systematic circulation. Secondary outcomes included all reported parameters other than the primary outcomes. The search identified a total of 2242 records; 39 reports from 32 studies met the eligibility criteria. This meta-analysis focused on the most relevant clinical end points; the mean difference (MD) in HbA1c levels during CIPII was significantly lower than during CSII (MD = -6.7 mmol/mol, [95% CI: -10.3 –-3.1]; in percentage: MD = -0.61%, [95% CI: -0.94 –- 0.28], p = 0.0002), whereas fasting blood glucose levels were similar (MD = 0.20 mmol/L, [95% CI: -0.34–0.74], p = 0.47; in mg/dL: MD = 3.6 mg/dL, [95% CI: -6.1–13.3], p = 0.47). The frequencies of severe hypo- and hyper-glycaemia were reduced. The fasting insulin levels were significantly lower during CIPII than during CSII (MD = 16.70 pmol/L, [95% CI: -23.62 –-9.77], p < 0.0001). Compared to CSII treatment, CIPII treatment improved overall glucose control and reduced fasting insulin levels in patients with DM1.
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Affiliation(s)
- Ilze Dirnena-Fusini
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- * E-mail:
| | - Marte Kierulf Åm
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Endocrinology, St. Olav’s University Hospital, Trondheim, Norway
| | - Anders Lyngvi Fougner
- Department of Engineering Cybernetics, Faculty of Information Technology and Electrical Engineering, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sven Magnus Carlsen
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Endocrinology, St. Olav’s University Hospital, Trondheim, Norway
| | - Sverre Christian Christiansen
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Endocrinology, St. Olav’s University Hospital, Trondheim, Norway
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Morioka F, Tani N, Ikeda T, Hirokawa T, Ikeda K, Shida A, Aoki Y, Ishikawa T. Morphological and biochemical changes in the pancreas associated with acute systemic hypoxia. Hum Cell 2021; 34:400-418. [PMID: 33532907 PMCID: PMC7900369 DOI: 10.1007/s13577-020-00481-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/30/2020] [Indexed: 11/05/2022]
Abstract
This study aimed to investigate the changes associated with acute systemic hypoxia in the endocrine system, particularly in pancreatic tissues. The investigation was based on macroscopic, pathohistological, biochemical, and molecular biological findings in cell lines and human cadavers. The results showed that cases of death due to asphyxia more frequently showed severe subcapsular/interstitial hemorrhage versus the other causes of death. Histological examination showed that asphyxia cases were associated with severe morphological changes. Although measured insulin levels in the asphyxia were higher compared to other causes of death, no differences were noted for the glucagon and amylase levels with regard to the cause of death. Increased blood insulin levels were not associated with macro- and micromorphological changes, and did not show any association with glucose or cortisol levels. The experiment conducted under hypoxic conditions in cultured cells demonstrated that insulin mRNA expression and insulin protein levels peaked at 10 min after hypoxia exposure. However, there were no changes in either the amylase mRNA or protein levels. Corticosterone level peaked at 120 min after exposure to hypoxic conditions. Overall, acute systemic hypoxic conditions can directly affect the mechanisms involved in pancreatic insulin secretion.
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Affiliation(s)
- Fumiya Morioka
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan.
| | - Naoto Tani
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan.,Forensic Autopsy Section, Medico-Legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan
| | - Tomoya Ikeda
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan.,Forensic Autopsy Section, Medico-Legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan
| | - Tatsuya Hirokawa
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan.,Forensic Autopsy Section, Medico-Legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan
| | - Kei Ikeda
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan
| | - Alissa Shida
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan
| | - Yayoi Aoki
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan
| | - Takaki Ishikawa
- Department of Legal Medicine, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno, Osaka, 545-8585, Japan.,Forensic Autopsy Section, Medico-Legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan
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8
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Butler OL, Mekhael MM, Ahmed A, Cuthbertson DJ, Pritchard DM. Frequency and Causes of False-Positive Elevated Plasma Concentrations of Fasting Gut Hormones in a Specialist Neuroendocrine Tumor Center. Front Endocrinol (Lausanne) 2020; 11:606264. [PMID: 33391185 PMCID: PMC7774602 DOI: 10.3389/fendo.2020.606264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/16/2020] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION In the UK, the fasting plasma concentrations of a panel of gut hormones (comprising vasoactive intestinal peptide (VIP), gastrin, pancreatic polypeptide (PP), glucagon, somatostatin and chromogranin A) are measured to evaluate patients who have or who (due to unexplained and compatible symptoms) are suspected of having neuroendocrine tumors (NETs). False positive elevated hormone concentrations are sometimes found. OBJECTIVE To evaluate the frequency and implications of false positive fasting gut hormone results. METHODS Retrospective audit of fasting gut hormone profile results at a large UK university teaching hospital over 12 months. RESULTS Fasting gut hormone concentrations were measured in 231 patients during 2017. No NETs were found in the 88 patients who had this test performed only to investigate symptoms. 31 false positive gastrin, 8 false positive chromogranin A, two false positive glucagon, three false positive somatostatin, one false positive PP, and one false positive VIP results were found. We extended the audit for glucagon and somatostatin for an additional two years and found seven probable false-positive raised glucagon concentrations and four probable false-positive elevated plasma somatostatin concentrations in total. CONCLUSIONS False-positive elevations of plasma gastrin and chromogranin A were common and causes such as proton pump inhibitor use or inadequate fasting accounted for most cases. Elevated plasma concentrations of the other gut hormones were also detected in patients who had no other evidence of NET. Other diagnoses (e.g. cirrhosis and medullary thyroid carcinoma for hypersomatostatinemia and type 2 diabetes mellitus, pancreatitis, liver or renal impairment for hyperglucagonemia) may cause these false positive results.
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Affiliation(s)
- Olivia L. Butler
- School of Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Monica M. Mekhael
- School of Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Arslan Ahmed
- School of Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Daniel J. Cuthbertson
- Insitute of Lifecourse and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
- ENETS Centre of Excellence, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom
| | - D. Mark Pritchard
- ENETS Centre of Excellence, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- *Correspondence: D. Mark Pritchard,
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9
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Diabetic Myopathy: current molecular understanding of this novel neuromuscular disorder. Curr Opin Neurol 2018; 30:545-552. [PMID: 28665810 DOI: 10.1097/wco.0000000000000479] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE OF REVIEW Here we summarize the evidence from human studies of the impairments to the structural, functional, and metabolic capacities in skeletal muscle in those with type 1 diabetes (T1D) - a condition known as diabetic myopathy. Given the importance of skeletal muscle for blood lipid and glucose management, the development and progression of diabetic myopathy would not only lead to increased insulin resistance, but also impact the ability to mitigate dysglycemic/dyslipidemic burdens. RECENT FINDINGS Despite the importance of skeletal muscle in whole-body metabolic control, studies investigating diabetic myopathy are startling limited. Recent findings have demonstrated that those with T1D exhibit decreased force production, increased fatigability, loss of muscle stem cells, and a greater reliance on glycolytic metabolism, as a result of reduced mitochondrial capacity. SUMMARY We propose a mechanistic model for the development of diabetic myopathy based on the human findings to date. This model suggests that repeated insulin injections in those with T1D leads to recurrent periods of intracellular hyperglycemia in myofibers. Resultant reductions in mitochondrial function lead to greater reliance on glycolytic metabolism and a concomitant shift in fiber type composition. Studies defining the scope and magnitude of diabetic myopathy and testing the veracity of this model are urgently needed in order to develop appropriate therapeutic strategies to maximize muscle health in those with T1D.
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10
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Kowalski GM, Moore SM, Hamley S, Selathurai A, Bruce CR. The Effect of Ingested Glucose Dose on the Suppression of Endogenous Glucose Production in Humans. Diabetes 2017; 66:2400-2406. [PMID: 28684634 DOI: 10.2337/db17-0433] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/21/2017] [Indexed: 11/13/2022]
Abstract
Insulin clamp studies have shown that the suppressive actions of insulin on endogenous glucose production (EGP) are markedly more sensitive than for stimulating glucose disposal (Rd). However, clamp conditions do not adequately mimic postprandial physiological responses. Here, using the variable infusion dual-tracer approach, we used a threefold range of ingested glucose doses (25, 50, and 75 g) to investigate how physiological changes in plasma insulin influence EGP in healthy subjects. Remarkably, the glucose responses were similar for all doses tested, yet there was a dose-dependent increase in insulin secretion and plasma insulin levels. Nonetheless, EGP was suppressed with the same rapidity and magnitude (∼55%) across all doses. The progressive hyperinsulinemia, however, caused a dose-dependent increase in the estimated rates of Rd, which likely accounts for the lack of a dose effect on plasma glucose excursions. This suggests that after glucose ingestion, the body preferentially permits a transient and optimal degree of postprandial hyperglycemia to efficiently enhance insulin-induced changes in glucose fluxes, thereby minimizing the demand for insulin secretion. This may represent an evolutionarily conserved mechanism that not only reduces the secretory burden on β-cells but also avoids the potential negative consequences of excessive insulin release into the systemic arterial circulation.
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Affiliation(s)
- Greg M Kowalski
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
| | - Samantha M Moore
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
| | - Steven Hamley
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
| | - Ahrathy Selathurai
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
| | - Clinton R Bruce
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
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Edgerton DS, Kraft G, Smith M, Farmer B, Williams PE, Coate KC, Printz RL, O'Brien RM, Cherrington AD. Insulin's direct hepatic effect explains the inhibition of glucose production caused by insulin secretion. JCI Insight 2017; 2:e91863. [PMID: 28352665 DOI: 10.1172/jci.insight.91863] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Insulin can inhibit hepatic glucose production (HGP) by acting directly on the liver as well as indirectly through effects on adipose tissue, pancreas, and brain. While insulin's indirect effects are indisputable, their physiologic role in the suppression of HGP seen in response to increased insulin secretion is not clear. Likewise, the mechanisms by which insulin suppresses lipolysis and pancreatic α cell secretion under physiologic circumstances are also debated. In this study, insulin was infused into the hepatic portal vein to mimic increased insulin secretion, and insulin's indirect liver effects were blocked either individually or collectively. During physiologic hyperinsulinemia, plasma free fatty acid (FFA) and glucagon levels were clamped at basal values and brain insulin action was blocked, but insulin's direct effects on the liver were left intact. Insulin was equally effective at suppressing HGP when its indirect effects were absent as when they were present. In addition, the inhibition of lipolysis, as well as glucagon and insulin secretion, did not require CNS insulin action or decreased plasma FFA. This indicates that the rapid suppression of HGP is attributable to insulin's direct effect on the liver and that its indirect effects are redundant in the context of a physiologic increase in insulin secretion.
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Affiliation(s)
- Dale S Edgerton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Guillaume Kraft
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Marta Smith
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Ben Farmer
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Phillip E Williams
- Division of Surgical Research, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Katie C Coate
- Samford University, Department of Nutrition and Dietetics, Birmingham, Alabama, USA
| | - Richard L Printz
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Richard M O'Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Alan D Cherrington
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
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12
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Edgerton DS, Moore MC, Winnick JJ, Scott M, Farmer B, Naver H, Jeppesen CB, Madsen P, Kjeldsen TB, Nishimura E, Brand CL, Cherrington AD. Changes in glucose and fat metabolism in response to the administration of a hepato-preferential insulin analog. Diabetes 2014; 63:3946-54. [PMID: 24947349 PMCID: PMC4392933 DOI: 10.2337/db14-0266] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Endogenous insulin secretion exposes the liver to three times higher insulin concentrations than the rest of the body. Because subcutaneous insulin delivery eliminates this gradient and is associated with metabolic abnormalities, functionally restoring the physiologic gradient may provide therapeutic benefits. The effects of recombinant human insulin (HI) delivered intraportally or peripherally were compared with an acylated insulin model compound (insulin-327) in dogs. During somatostatin and basal portal vein glucagon infusion, insulin was infused portally (PoHI; 1.8 pmol/kg/min; n = 7) or peripherally (PeHI; 1.8 pmol/kg/min; n = 8) and insulin-327 (Pe327; 7.2 pmol/kg/min; n = 5) was infused peripherally. Euglycemia was maintained by glucose infusion. While the effects on liver glucose metabolism were greatest in the PoHI and Pe327 groups, nonhepatic glucose uptake increased most in the PeHI group. Suppression of lipolysis was greater during PeHI than PoHI and was delayed in Pe327 infusion. Thus small increments in portal vein insulin have major consequences on the liver, with little effect on nonhepatic glucose metabolism, whereas insulin delivered peripherally cannot act on the liver without also affecting nonhepatic tissues. Pe327 functionally restored the physiologic portal-arterial gradient and thereby produced hepato-preferential effects.
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Affiliation(s)
- Dale S Edgerton
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Mary C Moore
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Jason J Winnick
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Melanie Scott
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Ben Farmer
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | | | | | | | | | | | | | - Alan D Cherrington
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
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Erice E, Llop E, Berzigotti A, Abraldes JG, Conget I, Seijo S, Reverter E, Albillos A, Bosch J, García-Pagán JC. Insulin resistance in patients with cirrhosis and portal hypertension. Am J Physiol Gastrointest Liver Physiol 2012; 302:G1458-65. [PMID: 22492691 DOI: 10.1152/ajpgi.00389.2011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Insulin resistance (IR) is involved in the pathogenesis of endothelial dysfunction and is also present in patients with cirrhosis. Intrahepatic endothelial dysfunction plays a major role, increasing hepatic vascular resistance and promoting portal hypertension (PH). In addition, β-adrenergic agonists and insulin share several intracellular signaling pathways. Thus IR may influence the response to β-blockers. This study aimed at evaluating the relationship between IR and hepatic hemodynamics in patients with cirrhosis and with the portal pressure response to acute β-blockade. Forty-nine patients with cirrhosis and PH were included. Hepatic and systemic hemodynamics were measured, and IR was estimated by using the updated homeostasis model assessment (HOMA)-2 index. Patients with HOMA-2 > 2.4 were considered IR. In patients with hepatic venous pressure gradient (HVPG) ≥ 10 mmHg) [clinically significant PH (CSPH)], hemodynamic measurements were performed again 20 min after intravenous propranolol. Mean HOMA-2 index was 3 ± 1.4. Fifty-seven percent of patients had IR. A weak correlation between HOMA-2 index and HVPG was observed. Eighty-six percent of patients had CSPH. HOMA-2 index was an independent predictor of CSPH. However, in patients with CSPH, the correlation between HOMA-2 index and HVPG was lost. HVPG, but not IR, predicted the presence of esophageal varices. Response to propranolol was not different between patients with or without IR. In nondiabetic patients with cirrhosis, HOMA-2 index is directly associated with the presence of CSPH and indirectly with varices, but does not allow either grading HVPG or predicting its response to propranolol.
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Affiliation(s)
- Eva Erice
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Barcelona, Spain
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14
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Schultess J, van Duren C, Martens M, Costa M, Llop T, Martí T, Eppinger M, Hausmann M, Krack W, Dhein J. Diagnostic performance of the ARCHITECT C-Peptide immunoassay. Clin Chem Lab Med 2009; 47:834-41. [DOI: 10.1515/cclm.2009.185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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Gooley JL, Walters JM, Ward GM. The minimal model of glucose disposal in the analysis of glucose effectiveness: importance of early insulin data. Diabetes Technol Ther 2009; 11:25-30. [PMID: 19132852 DOI: 10.1089/dia.2008.0018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Glucose effectiveness (S(g)) is an important component in glucose tolerance. Values of S(g) using "open loop" glucose kinetic computer programs are usually higher compared to closed loop method (CLM) programs that incorporate insulin secretion modeling. We aimed to test whether these differences are caused by (1) inclusion of insulin secretion modeling or (2) the method of representing plasma insulin values in the first few minutes of the frequently sampled intravenous glucose tolerance test (FSIGT). METHODS FSIGTs without insulin supplementation were performed in six healthy volunteers, and the Bergman minimal model was fitted to the data using the simulation and modeling program SAAM. RESULTS The CLM, which represents the insulin data in the first few minutes by a best-fit curve extrapolated to the y-axis, yielded a significantly lower S(g) than the approach similar to the computer program MINMOD, where the first few minutes of insulin data are represented by a line joining the basal to the peak values (1.55 +/- 0.28 vs. 1.97 +/- 0.27 [SE] x 10(-2)/min, P < 0.05). This second analysis was then repeated while forcing the program to represent the insulin data after the insulin peak in the same way as in the CLM, obtaining an almost identical result for S(g) (1.99 +/- 0.29). Insulin sensitivity was not significantly affected. CONCLUSIONS The higher S(g) estimates are caused by the method of representing the first few minutes of insulin data rather than by the incorporation of insulin secretion modeling. It is, therefore, important to know how the early insulin data are represented when comparing results from different computer modeling programs.
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Affiliation(s)
- Judith L Gooley
- Department of Medicine, St. Vincent's Hospital, University of Melbourne, Victoria, Australia
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16
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Schulte-Frohlinde E, Wagenpfeil S, Willis J, Lersch C, Eckel F, Schmid R, Schusdziarra V. Role of meal carbohydrate content for the imbalance of plasma amino acids in patients with liver cirrhosis. J Gastroenterol Hepatol 2007; 22:1241-8. [PMID: 17688664 DOI: 10.1111/j.1440-1746.2006.04620.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIM Imbalance of circulating branched chain amino acids (BCAA) versus aromatic amino acids (AAA) and hyperinsulinemia are common metabolic alterations in patients with liver cirrhosis. The aim of this study was to characterize the effect of the carbohydrate component of a protein-rich mixed meal on postprandial plasma concentrations of 21 amino acids, insulin and C-peptide in patients with compensated liver cirrhosis. Furthermore, the effect of a dietary intervention on the metabolic alterations in cirrhotic patients was examined. METHODS Eighteen patients with cirrhosis and 12 healthy volunteers received a protein-rich meal (pork filet 200 g) with or without carbohydrates (bread 50 g, glucose 20 g). A subgroup of four cirrhotic patients received an isoenergetic (117 kJ/kg bw) carbohydrate-enriched (60%) and -restricted (20%) diet for 7 days each. RESULTS In the cirrhotic patients, basal plasma insulin and C-peptide concentrations were significantly elevated. The ingestion of a protein-rich meal without additional carbohydrates led to a significantly greater increase of insulin and C-peptide in the cirrhotic patients compared to controls. Postprandial increases of leucine and isoleucine were reduced, whereas those of phenylalanine were higher in cirrhotic patients. The addition of carbohydrates led to higher insulin and C-peptide plasma concentrations in cirrhotic patients. Postprandial BCAA increases were more impaired in the cirrhotic group after additional carbohydrate ingestion (46%vs 82%). After the carbohydrate-restricted diet for 7 days BCAA plasma levels increased but the BCAA/AAA ratio remained unaltered. CONCLUSIONS The carbohydrate content of a meal enhances reduction of BCAA plasma concentrations in clinically stable cirrhotic patients. An imbalanced BCAA/AAA ratio cannot be avoided by a carbohydrate-reduced diet alone, supporting mandatory BCAA supplementation.
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17
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Wang XZ, Zhang LJ, Li D, Huang YH, Chen ZX, Li B. Effects of transmitters and interleukin-10 on rat hepatic fibrosis induced by CCl 4. World J Gastroenterol 2003; 9:539-43. [PMID: 12632514 PMCID: PMC4621578 DOI: 10.3748/wjg.v9.i3.539] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the effects of transmitters ET, AgII, PGI2, CGRP and GG on experimental rat hepatic fibrosis and the antifibrogenic effects of IL-10.
METHODS: One hundred SD rats were randomly divided into 3 groups: control group (N): intraperitoneal injection with saline 2 mL·kg-1 twice a week; the fibrogenesis group (C): intraperitoneal injection with 50% CCl4 2 mL·kg-1 twice a week; IL-10 treated group (E): besides same dosage of CCl4 given, intraperitoneal injection with IL-10 4 μg·kg-1 from the third week. In the fifth, the seventh and the ninth week, rats in three groups were selected randomly to collect plasma and liver tissues. The levels of ET, AgII, PGI2, CGRP and GG were assayed by radioimmunoassay (RIA). The liver fibrosis was observed with silver staining.
RESULTS: The hepatic fibrosis was developed with the increase of the injection frequency of CCl4. The ET, AgII, PGI2, CGRP and GG levels in serum of group N were 71.84 ± 60.2 ng·L-1, 76.21 ± 33.3 ng·L-1, 313.03 ± 101.71 ng·L-1, 61.97 ± 21.4 ng·L-1 and 33.62 ± 14.37 ng·L-1, respectively; the levels of them in serum of group C were 523.30 ± 129.3 ng·L-1, 127.24 ± 50.0 ng·L-1, 648.91 ± 357.29 ng·L- 1, 127.15 ± 62.0 ng·L-1 and 85.26 ± 51.83 ng·L- 1, respectively; the levels of them in serum of group E were 452.52 ± 99.5 ng·L-1, 90.60 ± 44.7 ng·L-1, 475.57 ± 179.70 ng·L-1, 102.2 ± 29.7 ng·L-1 and 38.05 ± 19.94 ng·L-1, respectively. The histological examination showed that the degrees of the rats liver fibrosis in group E were lower than those in group C.
CONCLUSION: The transmitters ET, AgII, PGI2, CGRP and GG play a significant role in the rat hepatic fibrosis induced by CCl4. IL-10 has the antagonistic action on these transmitters and can relieve the degree of the liver fibrosis.
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Affiliation(s)
- Xiao-Zhong Wang
- Department of Gastroenterology, The Affiliated Union Hospital, Fujian Medical University, Fuzhou, 350001, Fujian Province, China.
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18
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Hayakawa J, Motohashi H, Sairenji M, Kobayashi O, Takahashi M, Usuda Y. The effects of intraoperative glucose infusion on portal blood insulin concentration and hepatic mitochondrial redox state during surgery: comparison of short-term and continuous infusions. Surg Today 2001; 30:228-34. [PMID: 10752774 DOI: 10.1007/s005950050050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The relationships between the blood glucose level, portal blood immunoreactive insulin (IRI) concentration, ketogenesis, and hepatic mitochondrial redox state associated with intraoperative glucose administration were evaluated in patients undergoing total gastrectomy. A total of 26 patients were randomly allocated to two groups according to the type of infusion given; group 1 was given a short-term glucose infusion of 25 g in 30 min and group 2 was given a continuous glucose infusion of 10 g/h. The blood glucose concentration peaked 30 min after the glucose infusion was commenced, then decreased in group 1, despite a continuous rise in group 2. A temporary but significantly higher blood glucose level was observed in group 1 than in group 2, 30 and 60 min after the infusion was commenced. The portal blood IRI concentrations and arterial ketone body ratio (AKBR) continued to increase and the blood ketone body concentrations continued to decline after the start of the glucose infusion in both groups; however, after 60 and 120 min, the portal blood IRI and AKBR levels were significantly higher, and the blood ketone body levels significantly lower in group 1 than in group 2. These findings suggest that intraoperative glucose administration is beneficial for insulin secretion, ketogenesis, and the hepatic mitochondrial redox state, and that short-term infusion is superior to continuous infusion.
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Affiliation(s)
- J Hayakawa
- Department of Anesthesia, Kanagawa Cancer Center Hospital, Yokohama, Japan
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19
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Schneiter P, Gillet M, Chioléro R, Jéquier E, Tappy L. Hepatic nonoxidative disposal of an oral glucose meal in patients with liver cirrhosis. Metabolism 1999; 48:1260-6. [PMID: 10535388 DOI: 10.1016/s0026-0495(99)90265-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Seven patients with liver cirrhosis and five healthy subjects were studied over 4 hours after ingestion of a glucose meal to determine whether alterations of hepatic nonoxidative glucose disposal participate in the pathogenesis of impaired glucose tolerance. Hepatic uridyl-diphosphoglucose (UDPG) turnover was calculated from the isotopic enrichment of urinary acetaminophen glucuronide during continuous infusion of 13C-galactose and used as an index of hepatic glycogen synthesis. Patients with cirrhosis had postprandial hyperglycemia and decreased glucose clearance, but hepatic UDPG turnover was not altered (1.84 +/- 0.29 mg/kg fat-free mass min v 1.76 +/- 0.15 in controls, nonsignificant). It is concluded that hepatic postprandial glycogen synthesis is unaltered in patients with advanced cirrhosis, demonstrating important hepatic functional reserve.
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Affiliation(s)
- P Schneiter
- Institut de physiologie, Université de Lausanne, Switzerland
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20
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Hayakawa J, Tsuburaya A, Motohashi H, Sairenji M, Kobayashi O, Suzuki K, Usuda Y. Acute effects of distal pancreatectomy on portal and peripheral blood insulin concentrations in patients undergoing total gastrectomy. Surg Today 1998; 28:363-6. [PMID: 9590698 DOI: 10.1007/s005950050142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The influence of distal pancreatectomy on portal and peripheral blood immunoreactive insulin (IRI) and immunoreactive glucagon (IRG) concentrations was evaluated in patients undergoing total gastrectomy. There were 22 patients studied, 12 of whom did not undergo distal pancreatectomy (group 1), and 10 who did (group 2). In group 2, the increase in portal blood IRI concentrations after a glucose infusion of 25 g over 30 min was suppressed, and reelevation of the portal blood IRG concentration after the glucose-induced depression was inhibited compared to group 1. In contrast, the peripheral blood IRI concentration did not reflect these changes in the portal blood IRI concentration. The rise in the arterial ketone body ratio (AKBR) and the fall in the total ketone body concentration after glucose infusion were also attenuated after distal pancreatectomy in group 2. These findings suggest that distal pancreatectomy has an immediate suppressive effect on the pancreatic secretion of insulin and glucagon, and might disturb metabolism in the liver.
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Affiliation(s)
- J Hayakawa
- Department of Anesthesia, Kanagawa Cancer Center Hospital, Yokohama, Japan
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21
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Kruszynska YT, Goulas S, Wollen N, McIntyre N. Insulin secretory capacity and the regulation of glucagon secretion in diabetic and non-diabetic alcoholic cirrhotic patients. J Hepatol 1998; 28:280-91. [PMID: 9514541 DOI: 10.1016/0168-8278(88)80015-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND/AIMS Insulin secretion is increased in cirrhotic patients without diabetes but decreased in cirrhotic patients with diabetes. Increased glucagon secretion is found in both groups. Our aim was to determine: 1) whether alterations in insulin secretion are due to changes in maximal secretory capacity or altered islet B-cell sensitivity to glucose, and 2) whether regulation of glucagon secretion by glucose is disturbed. METHODS Insulin, C-peptide and glucagon levels were measured basally and during 12, 19 and 28 mmol/l glucose clamps, and in response to 5 g intravenous arginine basally and after 35 min at a glucose of 12, 19 and 28 mmol/l in 6 non-diabetic alcoholic cirrhotic patients, six diabetic alcoholic cirrhotic patients and six normal controls. RESULTS Fasting insulin, and C-peptide levels were higher in cirrhotic patients than controls but not different between diabetic and non-diabetic patients. C-peptide levels at t=35 min of the clamp increased more with glucose concentration in non-diabetic cirrhotic patients than controls; there was little increase in diabetic cirrhotic patients. At a blood glucose of approximately 5 mmol/l the 2-5 min C-peptide response to arginine (CP[ARG]) was similar in all groups, but enhancement of this response by glucose was greater in non-diabetic cirrhotic patients and impaired in diabetic cirrhotic patients. Maximal insulin secretion (CP(ARG) at 28 mmol/l glucose) was 49% higher in the non-diabetic cirrhotic patients than controls (p<0.05); in diabetic cirrhotic patients it was 47% lower (p<0.05). The glucose level required for half-maximal potentiation of (CPARG) was not different in the three groups. Cirrhotic patients had higher fasting glucagon levels, and a greater 2-5-min glucagon response to arginine, which was enhanced by concomitant diabetes (p<0.001 vs controls). Suppression of plasma glucagon by hyperglycaemia was markedly impaired in diabetic cirrhotic patients (glucagon levels at 35 min of 28 mmol/l glucose clamp: diabetics, 139 x/divided by 1.25 ng/l, non-diabetic cirrhotic patients, 24 x/divided by 1.20, controls, 21 x/divided by 1.15, p<0.001). Suppression of arginine-stimulated glucagon secretion by glucose was also impaired in diabetic cirrhotic patients, and to a lesser extent in non-diabetic cirrhotic patients. CONCLUSIONS Insulin secretory abnormalities in diabetic and non-diabetic cirrhotic patients are due to changes in maximal secretory capacity rather than altered B-cell sensitivity to glucose. The exaggerated glucagon response to arginine in alcoholic cirrhotic patients is not abolished by hyperglycaemia/hyperinsulinaemia. In diabetic alcoholic cirrhotic patients, the inhibitory effect of glucose on basal glucagon secretion is also markedly impaired.
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Affiliation(s)
- Y T Kruszynska
- Department of Endocrinology and Metabolism, VA Medical Center, University of California San Diego, La Jolla 92093, USA
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22
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Velussi M, Cernigoi AM, De Monte A, Dapas F, Caffau C, Zilli M. Long-term (12 months) treatment with an anti-oxidant drug (silymarin) is effective on hyperinsulinemia, exogenous insulin need and malondialdehyde levels in cirrhotic diabetic patients. J Hepatol 1997; 26:871-9. [PMID: 9126802 DOI: 10.1016/s0168-8278(97)80255-3] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIMS Several studies have demonstrated that diabetic patients with cirrhosis require insulin treatment because of insulin resistance. As chronic alcoholic liver damage is partly due to the lipoperoxidation of hepatic cell membranes, anti-oxidizing agents may be useful in treating or preventing damage due to free radicals. The aim of this study was to ascertain whether long-term treatment with silymarin is effective in reducing lipoperoxidation and insulin resistance in diabetic patients with cirrhosis. METHODS A 12-month open, controlled study was conducted in two well-matched groups of insulin-treated diabetics with alcoholic cirrhosis. One group (n=30) received 600 mg silymarin per day plus standard therapy, while the control group (n=30) received standard therapy alone. The efficacy parameters, measured regularly during the study, included fasting blood glucose levels, mean daily blood glucose levels, daily glucosuria levels, glycosylated hemoglobin (HbA1c) and malondialdehyde levels. RESULTS There was a significant decrease (p<0.01) in fasting blood glucose levels, mean daily blood glucose levels, daily glucosuria and HbA1c levels already after 4 months of treatment in the silymarin group. In addition, there was a significant decrease (p<0.01) in fasting insulin levels and mean exogenous insulin requirements in the treated group, while the untreated group showed a significant increase (p<0.05) in fasting insulin levels and a stabilized insulin need. These findings are consistent with the significant decrease (p<0.01) in basal and glucagon-stimulated C-peptide levels in the treated group and the significant increase in both parameters in the control group. Another interesting finding was the significant decrease (p<0.01) in malondialdehyde/levels observed in the treated group. CONCLUSIONS These results show that treatment with silymarin may reduce the lipoperoxidation of cell membranes and insulin resistance, significantly decreasing endogenous insulin overproduction and the need for exogenous insulin administration.
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Affiliation(s)
- M Velussi
- Anti-Diabetes Centre, Monfalcone Hospital, Gorizia, Italy
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23
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Record CO. Glucose and insulin metabolism in cirrhosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1997; 420:229-33. [PMID: 9286437 DOI: 10.1007/978-1-4615-5945-0_15] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- C O Record
- Liver Unit, Royal Victoria Infirmary and University of Newcastle upon Tyne, UK
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24
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Lin HC, Yang MC, Hou MC, Lee FY, Huang YT, Lin LF, Li SM, Hwang SJ, Wang SS, Tsai YT, Lee SD. Hyperglucagonaemia in cirrhotic patients and its relationship to the severity of cirrhosis and haemodynamic values. J Gastroenterol Hepatol 1996; 11:422-8. [PMID: 8743913 DOI: 10.1111/j.1440-1746.1996.tb00285.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Plasma glucagon concentrations were measured in 160 cirrhotic patients (Pugh's grade A in 52 patients, Pugh's grade B in 64 patients and Pugh's grade C in 44 patients). These values were compared with plasma glucagon concentrations in 57 age and sex-matched healthy subjects. Systemic and portal haemodynamic measurements, effective renal plasma flow and creatinine clearance were recorded for each patient. Plasma glucagon levels were significantly increased in cirrhotic patients compared with healthy subjects. In addition, plasma glucagon levels were higher in cirrhotic patients with ascites than in those without ascites and were increased in relation to the severity of cirrhosis as assessed by Pugh's score. Multiple linear regression found that only Child-Pugh's score was estimated to be an independent predictor of hyperglucagonaemia in cirrhotic patients. However, in patients with different degrees of oesophageal varices and in patients without oesophageal varices, plasma glucagon concentrations were no different among the different groups of patients, but were still higher than plasma glucagon concentrations in healthy subjects. In contrast, plasma glucagon levels were negatively correlated with mean arterial pressure and systemic vascular resistance. The results of the present study suggest that impairment of liver function plays, in part, a role in increased plasma glucagon levels observed in patients with cirrhosis. In addition, these data support the hypothesis that hyperglucagonaemia may contribute, at least in part, to the pathogenesis of peripheral arterial vasodilatation in cirrhosis with portal hypertension.
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Affiliation(s)
- H C Lin
- Department of Medicine, Taipei Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China
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25
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Kabadi U, Fragstedt L. Impaired TSH secretion during sustained hyperglucagonemia in anesthetized dogs. Thyroid 1995; 5:389-93. [PMID: 8563478 DOI: 10.1089/thy.1995.5.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We previously demonstrated that hyperglucagonemia may be responsible for thyroid hormone alterations noted in some nonthyroidal illnesses. Since TSH secretion is also known to be altered in many subjects with several nonthyroidal illnesses, we assessed the influence of sustained hyperglucagonemia on TSH secretory pattern in 5 anesthetized dogs. Serum TSH concentrations were determined after a 16-h fast and again at intervals of 15 min during sustained hyperglucagonemia (515-645 pg/mL) induced by iv bolus administration of glucagon 0.1 mg followed by a continuous glucagon infusion 3 ng/kg/min for 3 h. TRH (200 micrograms) was administered iv at 60 min to assess the influence of sustained hyperglucagonemia on the hypothalamic pituitary thyrotroph axis during the study. A control study was also conducted using normal saline instead of glucagon, and both studies were performed in a randomized sequence. Basal TSH levels were not significantly different during both studies. However, serum TSH declined significantly during sustained hyperglucagonemia prior to TRH administration (delta TSH, pre-TRH, -0.86 +/- 0.24 vs 0.02 +/- 0.07 ng/mL for normal saline, p < 0.01). Furthermore, TSH response to iv TRH administration was significantly blunted during glucagon infusion alone as expressed by both the absolute rise (delta TSH, post-TRH, 1.1 +/- 0.5 vs 5.9 +/- 1.7 ng/ml for normal saline, p < 0.01) as well as an integrated response over a 2-h period (sigma TSH, post-TRH, 4.0 +/- 1.1 vs 11.7 +/- 3.5 ng/min/mL, p < 0.001). Therefore, this study demonstrates that sustained hyperglucagonemia inhibits basal TSH secretion as well as TSH response to iv TRH administration, a TSH secretory pattern similar to that noted at the peak of many nonthyroidal illnesses.
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Affiliation(s)
- U Kabadi
- VA Medical Center, Des Moines, Iowa 50310, Iowa 52242, and School of Medicine, University of Arizona, Tucson, Arizona 85724, USA
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26
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Kaneko K, Arai M, Funatomi H, Hatta Y, Mitamura K. Changes in immunoreactive insulin, C-peptide immunoreactivity, and immunoreactive glucagon in acute viral hepatitis. J Gastroenterol 1995; 30:624-31. [PMID: 8574335 DOI: 10.1007/bf02367789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Insulin and glucagon are thought to play important roles as hepatotrophic factors in acute viral hepatitis (AVH); however, few reports have investigated the responses and relationships of each of these hormones to liver damage in detail. We studied insulin and glucagon responses during the acute and recovery phases of AVH. We performed a glucose tolerance test (GTT) and an insulin sensitivity test (IST) in each phase in 11 patients with AVH. In 8 additional patients in the acute phase (total n = 19), were compared immunoreactive insulin (IRI) and C-peptide immunoreactivity (CPR) levels with transaminase levels. In the acute phase, IRI concentrations were normal from fasting to 60 min, despite an increased CPR level. In the recovery phase, IRI and CPR levels increased significantly. Immunoreactive glucagon levels in both phases did not differ significantly from those in controls. During the IST, the insulin sensitivity index in both phases was significantly lower than that in the controls. Fasting IRI and sigma IRI showed significant negative correlations with transaminase levels. We found enhanced insulin secretion and a decrease in plasma insulin in the acute phase of AVH. The discrepancy between IRI and CPR responses in the acute phase suggests an increase in the degradation or consumption of insulin in the liver.
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Affiliation(s)
- K Kaneko
- Second Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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27
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Castillo MJ, Scheen AJ, Letiexhe MR, Lefèbvre PJ. How to measure insulin clearance. DIABETES/METABOLISM REVIEWS 1994; 10:119-50. [PMID: 7956676 DOI: 10.1002/dmr.5610100205] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- M J Castillo
- Department of Medicine, CHU Liège, University of Liège, Belgium
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28
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Petrides AS, Vogt C, Schulze-Berge D, Matthews D, Strohmeyer G. Pathogenesis of glucose intolerance and diabetes mellitus in cirrhosis. Hepatology 1994; 19:616-27. [PMID: 8119686 DOI: 10.1002/hep.1840190312] [Citation(s) in RCA: 179] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Glucose intolerance and diabetes mellitus are both prevalent in cirrhosis, yet the pathogenesis of impaired glucose metabolism remains unknown. Therefore insulin secretion (hyperglycemic clamp, +125 mg/dl), insulin sensitivity (euglycemic hyperinsulinemic insulin clamp, +10 microU/ml and +50 microU/ml), whole-body glucose oxidation (indirect calorimetry) and glucose turnover ([6,6-2H2]glucose isotope dilution) were evaluated in a homogenous group of cirrhotic patients with glucose intolerance (n = 7) or frank diabetes mellitus (n = 6). The results were compared with those obtained in control subjects (n = 8). In glucose-intolerant patients, whole-body glucose uptake (mainly reflecting glucose utilization by muscle) was significantly impaired in patients during both insulin infusions as a result of decreased stimulation of the two major intracellular pathways of glucose disposal--nonoxidative glucose disposal (i.e., glycogen synthesis) and glucose oxidation. Hepatic glucose production was normal in the basal state and was normally suppressed during stepwise insulin infusion (by 65% and 85%, respectively, p = NS vs. controls). Hyperglycemia-induced increases of plasma C-peptide concentrations were comparable to those in controls (p = NS). In diabetic patients, insulin-mediated glucose uptake was significantly reduced, mainly because of impaired non-oxidative glucose disposal. Glucose oxidation appeared to be reduced, too. Hepatic glucose production was significantly increased in the basal state (3.03 +/- 0.24 vs. 2.34 +/- 0.10 mg/kg min, p < 0.02) and during insulin infusion (+50 microU/ml: 0.67 +/- 0.17 vs. 0.13 +/- 0.08 mg/kg min, p < 0.05) compared with that in controls. Both the first and second phases of beta-cell secretion were significantly reduced in response to steady-state hyperglycemia (both p < 0.01 vs. control values). In conclusion, glucose intolerance in cirrhosis results from two abnormalities that occur simultaneously: (a) insulin resistance of muscle and (b) an inadequate response (even when comparable to that of controls) of the beta-cells to appropriately secrete insulin to overcome the defect in insulin action. Diabetes mellitus in insulin-resistant cirrhotic patients develops as the result of progressive impairment in insulin secretion together with the development of hepatic insulin resistance leading to fasting hyperglycemia and a diabetic glucose tolerance profile.
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Affiliation(s)
- A S Petrides
- Department of Internal Medicine, Heinrich-Heine University, Düsseldorf, Germany
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Abstract
The direct feedback regulation between the endocrine gland and its target organ is an expected biological relationship. However, such a phenomenon is far from being well established in the case of the endocrine pancreas and its major target organ, the liver, especially since plasma glucose has been established as the prime regulator. In this perspective, I have reexamined the feedback regulation between plasma glucose and glucagon secretion by the pancreatic alpha cell. Surprisingly, available data in the literature appear to document a frequent breakdown of this well-established interdependence between plasma glucose and pancreatic alpha cells, as reflected by a sustained elevation of plasma glucagon levels in several physiologic and pathologic states with concurrent euglycemia or hyperglycemia. Moreover, normal or low glucagon concentrations in the presence of fasting hypoglycemia in patients with insulinoma or non-islet cell tumors secreting insulin-like peptides and in patients with hepatic glycogen storage disorders may enhance our hypothesis that plasma glucose level may not be the major regulator of glucagon secretion. Extensive data in the literature show that hyperglucagonemic states are characterized by a unique metabolic environment, namely hepatic glycogen depletion. Similarly, hepatic glycogen stores are abundant in the presence of normal or low glucagon concentrations. These findings imply a distinct relationship between hepatic glycogen content and plasma glucagon level.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- U M Kabadi
- Endocrinology Section, Veterans Administration Medical Center, Phoenix, AZ 85012
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Velussi M, Cernigoi A, Viezzoli L, Dapas F, Caffau C, Zilli M. Silymarin reduces hyperinsulinemia, malondialdehyde levels, and daily insulin need in cirrhotic diabetic patients. CURRENT THERAPEUTIC RESEARCH 1993. [DOI: 10.1016/s0011-393x(05)80660-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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31
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Cavallo-Perin P, Bruno A, Scaglione L, Gruden G, Cassader M, Pagano G. Feedback inhibition of insulin and glucagon secretion by insulin is altered in abdominal obesity with normal or impaired glucose tolerance. Acta Diabetol 1993; 30:154-8. [PMID: 8111076 DOI: 10.1007/bf00572860] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We investigated the feedback inhibition of insulin and glucagon secretion during euglycemic-hyperinsulinemic clamp at about 350 pmol/l in 16 patients with abdominal obesity [8 with normal glucose tolerance (oNGT), 8 with impaired glucose tolerance (oIGT)] and 8 normal-weight subjects matched for age, sex and blood pressure. In oNGT and oIGT, fasting plasma C-peptide levels were twice those in the controls (962 +/- 51 and 915 +/- 85 vs 439 +/- 28 pmol/l, P < 0.001) and their suppression was lower than in the controls, both in absolute terms (155 +/- 19 and 185 +/- 17 vs 274 +/- 18 pmol/l, P < 0.001) and as a percentage decline from basal levels (16 +/- 2% and 21 +/- 2% vs 63 +/- 2%, P < 0.001). Fasting plasma glucagon levels were similar in the patients and in the controls, but were less suppressed during clamp in oNGT and oIGT, both in absolute terms (7.0 +/- 0.9 and 5.6 +/- 0.6 vs 13.2 +/- 1.2 pmol/l, P < 0.001) and as a percentage change from basal levels (23 +/- 3% and 19 +/- 2% vs 44 +/- 4%, P < 0.001). These results suggest that the insulin feedback on B and A cells is impaired in abdominal obesity, and that this defect is of similar degree in oNGT and oIGT. These alterations could be implicated in the pathogenesis of hyperinsulinemia in obesity.
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Shmueli E, Record CO, Alberti KG. Liver disease, carbohydrate metabolism and diabetes. BAILLIERE'S CLINICAL ENDOCRINOLOGY AND METABOLISM 1992; 6:719-43. [PMID: 1445166 DOI: 10.1016/s0950-351x(05)80163-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- E Shmueli
- Royal Victoria Infirmary, Newcastle Upon Tyne, UK
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Morishima T, Pye S, Bradshaw C, Radziuk J. Posthepatic rate of appearance of insulin: measurement and validation in the nonsteady state. THE AMERICAN JOURNAL OF PHYSIOLOGY 1992; 263:E772-9. [PMID: 1415699 DOI: 10.1152/ajpendo.1992.263.4.e772] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
To assess the accuracy with which insulin appearance rates in the peripheral circulation can be measured out of steady state, seven conscious dogs were simultaneously infused with somatostatin and insulin at known variable rates. Tritiated insulin was infused concurrently at a constant rate. Insulin rates of appearance were estimated continuously on the basis of a two-compartment model for systemic insulin kinetics. The calculations were performed assuming that insulin kinetics were linear (tracer data not used) and nonlinear or time varying (tracer data used to assess the variation). The average error in areas under the curve was -3.5 +/- 2.5 and 27.0 +/- 14.2% when nonlinear or linear kinetics were assumed. The maximal errors when linearity was assumed was 39.9 +/- 11.3% and decreased to 16.3 +/- 2.6% when the tracer data was used to account for changes in the fractional removal rate of insulin. The accuracy of the linear estimates improved as the fractional removal rate remained closer to constant. These data suggest that a priori assumptions should not be made on the linearity of the insulin system in a given experimental situation.
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Affiliation(s)
- T Morishima
- Department of Medicine, Royal Victoria Hospital, Montreal, Quebec, Canada
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Kruszynska YT, Home PD, McIntyre N. Relationship between insulin sensitivity, insulin secretion and glucose tolerance in cirrhosis. Hepatology 1991; 14:103-11. [PMID: 2066059 DOI: 10.1002/hep.1840140117] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Hepatic insulin extraction is difficult to measure in humans; as a result, the interrelationship between defective insulin secretion and insulin insensitivity in the pathogenesis of glucose intolerance in cirrhosis remains unclear. To reassess this we used recombinant human C-peptide to measure C-peptide clearance in cirrhotic patients and controls and thus derive C-peptide and insulin secretion rates after a 75-gm oral glucose load and during a 10 mmol/L hyperglycemic clamp. Cirrhotic patients were confirmed as insulin-insensitive during a euglycemic clamp (glucose requirement: 4.1 +/- 0.1 mg/kg/min vs. 8.1 +/- 0.5 mg/kg/min; p less than 0.001), which also demonstrated a low insulin metabolic clearance rate (p less than 0.001). Although intolerant after oral glucose, the cirrhotic patients had glucose requirements identical to those of controls during the hyperglycemic clamp (cirrhotic patients: 6.1 +/- 1.0 mg/kg/min; controls: 6.3 +/- 0.7 mg/kg/min), suggesting normal intravenous glucose tolerance. C-peptide MCR was identical in cirrhotic patients (2.93 +/- 0.16 ml/min/kg) and controls (2.96 +/- 0.24 ml/min/kg). Insulin secretion was higher in cirrhotic patients, both fasting (2.13 +/- 0.26 U/hr vs. 1.09 +/- 0.10 U/hr; p less than 0.001) and from min 30 to 90 of the hyperglycemic clamp (5.22 +/- 0.70 U/hr vs. 2.85 +/- 0.22 U/hr; p less than 0.001). However, with oral glucose the rise in serum C-peptide concentration was relatively delayed, and the insulin secretion index (secretion/area under 3-hr glucose curve) was not elevated. Hepatic insulin extraction was reduced both in fasting and during the hyperglycemic clamp (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- Y T Kruszynska
- Department of Medicine, Royal Free Hospital School of Medicine, London, United Kingdom
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Johansson U, Hagenfeldt L, Persson A, Siw Eriksson L. Parenteral nutrition in patients with liver cirrhosis. Effects on circulating levels of glucose and hormones and on cerebral function. Clin Nutr 1989; 8:321-7. [PMID: 16837308 DOI: 10.1016/0261-5614(89)90007-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/1988] [Accepted: 03/09/1989] [Indexed: 10/26/2022]
Abstract
The effects of 2 and 5 days of total parenteral nutrition (TPN; 70 g amino-acids, 100 g fat, 150 g glucose) on carbohydrate, fat and amino-acid levels and on cerebral function were investigated in 10 patients with alcoholic cirrhosis and 7 age-matched healthy controls. The results were compared to those after a standardised oral diet. During TPN, glucose concentrations increased slightly in both groups. Insulin concentrations also rose in both groups, but the rise was more pronounced in the patients, resulting in a 10-fold difference between the two groups after 6.5 hours (patients: 281 +/- 81 U/l; controls: 28 +/- 5 U/l; p < 0.02). Glucagon increased significantly during TPN in the patients only (33%, p < 0.05). Similar but less pronounced patterns were observed after the oral diet. The basal concentrations of free fatty acids and 3-OH-butyrate were higher in the patients than in the controls. However, during both oral and parenteral nutrition, the concentrations fell in both groups. For 3-OH-butyrate the difference between the groups disappeared, while the free fatty acid levels remained higher in the patients throughout the TPN administration. Basal triglyceride levels were similar in patients and controls and rose to a similar extent in both groups during TPN. Plasma amino-acid concentrations were typical for cirrhotic patients in the basal state: low levels of the branched-chain amino-acids (BCAA) and high concentrations of the aromatic amino-acids (AAA). During TPN BCAA, as well as AAA, increased in both patients and controls, resulting in unaltered BCAA AAA ratio. All patients performed poorly on psychometric tests (Number Connection Tests A and B; Digit Symbol) before the study, indicating subclinical encephalopathy. However, no deterioration was observed in any of the tests during five days of TPN. Similarly, EEG and visual evoked potentials were unchanged during the study, demonstrating that patients with severe alcoholic liver disease tolerate a balanced intravenous nutrition without adverse effects on cerebral function.
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Affiliation(s)
- U Johansson
- Department of Clinical Chemistry, Karolinska Hospital, Karolinska Institute, Stockholm, Sweden
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Petrides AS, DeFronzo RA. Glucose metabolism in cirrhosis: a review with some perspectives for the future. DIABETES/METABOLISM REVIEWS 1989; 5:691-709. [PMID: 2693018 DOI: 10.1002/dmr.5610050805] [Citation(s) in RCA: 96] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- A S Petrides
- Department of Internal Medicine, University of Dusseldorf, West Germany
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Obata H, Koga A. Glucose intolerance and pancreatic endocrine dysfunction in dogs with obstructive jaundice. GASTROENTEROLOGIA JAPONICA 1988; 23:666-72. [PMID: 3065135 DOI: 10.1007/bf02782953] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Mechanisms involved in pancreatic endocrine disturbances in the presence of obstructive jaundice were studied in mongrel dogs with a ligated bile duct. Slower disappearance rate of glucose (KG) and lower portal insulin responses within ten minutes following intravenous glucose loading were observed in jaundiced dogs than in the controls. Hyperglucagonemia in the portal vein was evident in jaundiced dogs for five weeks. Morphometrical analysis of the beta-cells showed that the volume density of secretory granules decreased in jaundiced dogs. However, in three types of beta-granules, the change of size was observed only in the bar-shaped core granules. The volume density of the rough endoplasmic reticulum increased whereas that of the Golgi apparatus decreased in jaundiced dogs for five weeks. In contrast with beta-cells, alpha-cells revealed no morphological changes in any groups. These findings suggest that the beta-granules fail to mature if there is an inhibition by a blockade of energy-requiring steps such as the ER-Golgi transfer system. Impairment of beta-granules is considered to lead to glucose intolerance. Hyperglucagonemia is probably secondary to abnormal beta-cell function, which causes insulin deficiency and the loss of the relation between alpha-cells and beta-cells.
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Affiliation(s)
- H Obata
- First Department of Surgery, Kyushu University Faculty of Medicine, Fukuoka, Japan
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Ichiba T, Tanaka A, Ohta Y. Adrenergic control of the glucagon response to ammonia in the perfused rat pancreas. Diabetes Res Clin Pract 1988; 5:177-84. [PMID: 3146494 DOI: 10.1016/s0168-8227(88)80085-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The isolated perfused rat pancreas was used to investigate how adrenergic influences within the pancreas might mediate ammonia-induced glucagon secretion. The addition of 2 mM ammonia to the perfusate increased norepinephrine release and glucagon secretion in the effluent. Upon cessation of ammonia addition, a pronounced burst of glucagon release was observed. Alpha-adrenergic blockade with phentolamine (10 microM) blocked the glucagon response to ammonia. Beta-adrenergic blockade with propranolol (10 microM) had no significant effect on the amount of glucagon release induced by ammonia. Depletion of norepinephrine from sympathetic nerve terminals by pretreatment with 6-hydroxydopamine lowered the pancreatic norepinephrine content to less than 16% of the control value and diminished the glucagon and norepinephrine response to ammonia almost completely. The burst of glucagon release after the removal of ammonia was inhibited to 2% of the control value by phentolamine and to 57% by propranolol. Pretreatment with 6-hydroxydopamine reduced the burst of glucagon secretion to 28% of the control value. Neither phentolamine nor propranolol reduced the magnitude of the ammonia-induced suppression of insulin secretion. We conclude that the effect of ammonia on glucagon release from the isolated rat pancreas is mediated by intrapancreatic adrenergic control.
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Affiliation(s)
- T Ichiba
- Third Department of Internal Medicine, Ehime University School of Medicine, Japan
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Nakamura T, Otsuki M, Tani S, Okabayashi Y, Fujii M, Oka T, Fujisawa T, Baba S. Pancreatic endocrine function in cirrhotic rats. Metabolism 1988; 37:892-9. [PMID: 3047524 DOI: 10.1016/0026-0495(88)90125-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Pancreatic endocrine function in liver cirrhosis was examined in rats both in vivo and in vitro. Experimental liver cirrhosis was induced by subcutaneous injections of 50% carbon tetrachloride in a dose of 2 mL/kg body weight twice a week for 16 weeks. Control rats received a similar dose of olive oil during the same period. In cirrhotic rats, immunoreactive insulin contents in the pancreas were significantly lower, whereas immunoreactive glucagon contents were about threefold higher than those of control rats. In the first part of this study, insulin and glucagon concentrations in both jugular and portal venous blood at basal conditions and after oral glucose loading were simultaneously determined in vivo. Peripheral insulin levels, both before and after glucose loading, were higher, whereas portal insulin concentrations were lower in cirrhotic rats than in the control rats. In contrast, glucagon levels in both the peripheral and portal veins were significantly higher in cirrhotic rats than in control rats. In the second part, isolated perfused pancreata were prepared from cirrhotic and control rats to further characterize the endocrine function of cirrhotic rat pancreas. Insulin secretion in response to 16.7 mmol/L glucose and 100 pmol/L cholecystokinin-octapeptide both were 40% lower in cirrhotic rats than in controls. In contrast, there was no significant difference in arginine-stimulated insulin release between the two groups. However, glucagon secretion in response to 20 mmol/L arginine was 40% higher in cirrhotic rats. If sensitivity is defined as the hormone release proportional to the pancreatic contents, then A and B cells in the cirrhotic rats had normal sensitivity to both glucose and cholecystokinin-octapeptide.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Nakamura
- Second Department of Internal Medicine, Kobe University School of Medicine, Japan
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Stremmel W, Niederau C, Berger M, Kley HK, Krüskemper HL, Strohmeyer G. Abnormalities in estrogen, androgen, and insulin metabolism in idiopathic hemochromatosis. Ann N Y Acad Sci 1988; 526:209-23. [PMID: 3291683 DOI: 10.1111/j.1749-6632.1988.tb55507.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Of 44 male patients with idiopathic hemochromatosis who were diagnosed at an early stage without morphological or biochemical evidence of liver disease, 25% suffered from impotence and 34% manifested glucose intolerance. Impotence was correlated with a 50% reduction in plasma testosterone, resulting from a 63% decrease in testosterone production. Testicular atrophy was caused by insufficient secretion of gonadotropins due to the selective accumulation of iron in gonadotropic cells of the pituitary gland. However, peripheral sexual hormone metabolism, in particular the conversion of androgens to estrogens, remained unaltered. It was therefore possible to employ substitution therapy successfully with testosterone in these men, and hyperestrogenism was not observed as a side effect. The pathogenetic factors in the development of diabetes mellitus in patients with idiopathic hemochromatosis include impaired insulin secretion caused by the selective deposition of iron in B-cells of the pancreas and insulin resistance due to iron accumulation in the liver. In particular, the insulin resistance is markedly improved after depletion of body iron stores by phlebotomy treatment, resulting in lower insulin requirements in patients with insulin-dependent diabetes as well as improvement of carbohydrate metabolisms in about half of the patients with non-insulin-dependent diabetes. We have concluded that hypogonadism and carbohydrate intolerance are caused by the specific distribution pattern of excess iron in the organism, accompanied by functional impairment of affected parenchymal cells.
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Affiliation(s)
- W Stremmel
- Division of Gastroenterology, Düsseldorf University Medical Center, Federal Republic of Germany
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Silva G, Gomis R, Bosch J, Casamitjana R, Mastai R, Navasa M, Rivera F, Rodés J. Hyperglucagonism and glucagon resistance in cirrhosis. Paradoxical effect of propranolol on plasma glucagon levels. J Hepatol 1988; 6:325-31. [PMID: 3392382 DOI: 10.1016/s0168-8278(88)80049-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Propranolol, a non-selective beta-blocker, is known to decrease glucagon release in normal subjects. The present study was aimed at investigating the effects of propranolol on the hyperglucagonism commonly observed in patients with cirrhosis. Eight cirrhotic patients and 6 matched healthy controls were studied. The plasma concentrations of glucagon, insulin, c-peptide and glucose were measured in basal conditions and after stimulating glucagon secretion by an i.v. infusion of arginine (0.4 g/kg/30 min). The study was repeated 24 h later after inducing beta-blockade by the i.v. infusion of propranolol (10 mg). In baseline conditions, patients with cirrhosis, despite normal levels of insulin and glucose, had a marked hyperglucagonism (654 +/- 303 pg/ml vs. 269 +/- 90 in controls, P less than 0.01). Prior to propranolol, arginine infusion caused greater glucagon release in cirrhotics (71 +/- 31 ng.h.ml-1) than in controls (33 +/- 17 ng.h.ml-1, P less than 0.02), but despite a similar insulin secretion (assessed from c-peptide), blood glucose did not increase. After propranolol, glucagon secretion decreased as expected in controls (29 +/- 12 ng.h.ml-1, P less than 0.05) but experienced a paradoxical increase in cirrhotics (113 +/- 64 ng.h.ml-1, P less than 0.05). Again, despite the marked increase in glucagon release, there was no increase in glucose production, providing further evidence of the glucagon resistance that accompanies hyperglucagonism in cirrhosis. Our results suggest that hyperglucagonism with glucagon resistance might be the initial disturbance in carbohydrate metabolism in patients with cirrhosis. Contrary to what could be expected, propranolol does not correct but further accentuates this disturbance.
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Affiliation(s)
- G Silva
- Liver Unit, Hospital Clinic i Provincial, University of Barcelona, School of Medicine, Spain
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Abstract
Fourteen normal controls, eleven patients with non-alcoholic cirrhosis, twenty-nine with hepatocellular carcinoma (HCC) and six with HCC and hypoglycemia were studied. The tests performed include iv glucose tolerance test (25 g) and glucagon challenge test (2 mg). In cirrhosis, glucose intolerance and insulin resistance were demonstrated. The fasting hyperinsulinemia in cirrhosis is the result of decreased degradation as shown by the normal fasting C-peptide. The increased insulin responses to glucose, despite a normal C-peptide response, further supports the importance of impaired degradation in the pathogenesis of hyperinsulinemia after challenge. Despite a strong etiological association between cirrhosis and HCC, patients with HCC do not have significant hyperinsulinemia or glucose intolerance. This provides metabolic evidence to support the clinico-pathological observation that HCC occurred when cirrhosis was not advanced or in a precirrhotic stage. In HCC patients with clinically overt hypoglycemia, the fasting glucose, insulin and C-peptide were very low. The C-peptide responses to glucose and glucagon challenges were suppressed despite pharmacologic stimulation. This can be explained by the suppression of insulin secretion by a circulating substance secreted by hepatoma. The results support the pathogenetic importance of insulin-like activities recently detected in HCC patients with hypoglycemia.
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Affiliation(s)
- K K Pun
- Department of Medicine, University of Hong Kong, Queen Mary Hospital
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Hother-Nielsen O, Schmitz O, Bak J, Beck-Nielsen H. Enhanced hepatic insulin sensitivity, but peripheral insulin resistance in patients with type 1 (insulin-dependent) diabetes. Diabetologia 1987; 30:834-40. [PMID: 3328718 DOI: 10.1007/bf00274790] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Sensitivity to insulin in vivo was studied in 8 normal weight C-peptide negative Type 1 (insulin-dependent) diabetic patients (age 23 +/- 1 years, diabetes duration 6 +/- 2 years), and in 8 age, weight and sex matched healthy subjects, using the euglycaemic clamp and 3-3H-glucose tracer technique. Prior to the study diabetic patients were maintained normoglycaemic overnight by a glucose controlled insulin infusion. Sequential infusions of insulin in 3 periods of 2 h resulted in mean steady state insulin levels of 12 +/- 2 versus 11 +/- 1, 18 +/- 2 versus 18 +/- 2 and 28 +/- 3 versus 24 +/- 2 microU/ml in diabetic patients and control subjects. Corresponding glucose utilization rates were 2.4 +/- 0.2 versus 2.4 +/- 0.1, 2.4 +/- 0.2 versus 3.0 +/- 0.3 and 2.9 +/- 0.3 versus 4.6 +/- 0.6 mg.kg-1.min-1, p less than 0.02. Portal insulin values in the three periods were calculated to 12 +/- 2 versus 25 +/- 3, 18 +/- 2 versus 32 +/- 3 and 28 +/- 3 versus 37 +/- 3 microU/ml in the diabetic patients and control subjects using peripheral insulin and C-peptide concentrations and assuming a portal to peripheral insulin concentration gradient of 1 in diabetic patients and of 2.4 in control subjects. Corresponding glucose production rates were 2.5 +/- 0.2 versus 2.4 +/- 0.1, 1.6 +/- 0.1 versus 0.9 +/- 0.2 and 0.7 +/- 0.1 versus 0.4 +/- 0.2 mg.kg-1.min-1.(ABSTRACT TRUNCATED AT 250 WORDS)
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Yoshiya K, Kishimoto T, Ishikawa Y, Utsunomiya J. Insulin response following intravenous glucose administration in dogs with obstructive jaundice. J Surg Res 1987; 43:271-7. [PMID: 3306155 DOI: 10.1016/0022-4804(87)90081-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In order to further clarify the circulating insulin kinetics in obstructive jaundice, five anesthetized dogs were given a 15-min intravenous infusion of 1 g/kg glucose before and during the first 1 to 2 weeks after a common bile duct ligation. Significantly higher blood glucose levels, a lower insulin response in femoral vein blood, and a lower initial insulin response in portal vein blood were observed following glucose administration in the animals with jaundice. The ratio of (integrated portal insulin response-integrated femoral insulin response)/(integrated portal insulin response) was significantly increased in the animals with jaundice when compared with that of the control animals. These results suggest that a low peripheral insulin response following glucose administration in obstructive jaundice is induced by an augmented insulin extraction in the liver and/or peripheral tissue as well as by an insulin hyposecretion from the pancreas.
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Ferrannini E, Cobelli C. The kinetics of insulin in man. II. Role of the liver. DIABETES/METABOLISM REVIEWS 1987; 3:365-97. [PMID: 3552527 DOI: 10.1002/dmr.5610030202] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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47
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Ballmann M, Hartmann H, Deacon CF, Schmidt WE, Conlon JM, Creutzfeldt W. Hypersecretion of proinsulin does not explain the hyperinsulinaemia of patients with liver cirrhosis. Clin Endocrinol (Oxf) 1986; 25:351-61. [PMID: 3304724 DOI: 10.1111/j.1365-2265.1986.tb01701.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A radioimmunoassay using a proinsulin-specific antiserum that does not react preferentially with the split forms of proinsulin has been used to compare the response of circulating proinsulin to low (25 g) and high (75 g) oral glucose loads in healthy subjects and in patients with liver cirrhosis. The patients were divided into two groups: Group A (n = 7) with normal glucose tolerance and Group B with diabetic (n = 5) and impaired (n = 1) glucose tolerance. There was no apparent correlation between glucose tolerance and the results of quantitative liver function tests. In the fasted state, the concentrations of serum proinsulin did not differ significantly in patients of Group A (0.022 +/- 0.002 nmol/l) or Group B (0.026 +/- 0.004 nmol/l) from those in healthy subjects (0.021 +/- 0.002 nmol/l). After 75 g glucose, the rise in serum proinsulin to a maximum concentration of 0.082 +/- 0.012 nmol/l in patients of Group A and to 0.070 +/- 0.019 nmol/l in Group B was not significantly different at any time point up to 180 min from the rise in healthy subjects (to 0.063 +/- 0.005 nmol/l). After 25 g glucose, the response of serum proinsulin in Group B patients (maximum concentration 0.035 +/- 0.003 nmol/l) was not significantly different from that in healthy subjects (maximum concentration 0.032 +/- 0.003 nmol/l) but a slightly enhanced release was observed in the Group A patients (maximum concentration 0.049 +/- 0.003 nmol/l) that was significantly greater (P less than 0.05) at 60 min post-glucose. In contrast, the concentrations of serum immunoreactive insulin and immunoreactive C-peptide in all patients with cirrhosis were significantly elevated compared with healthy subjects both in the fasted state and at several time points following high and low oral glucose. In the fasted state, the serum proinsulin/C-peptide molar ratio, an index of the relative state of secretion of proinsulin and insulin, was significantly lower (P less than 0.05) in both groups of cirrhotic patients than in healthy subjects. After high and low glucose, this ratio fell in all patients and in the healthy subjects. We conclude that cirrhosis of the liver is associated with a hypersecretion of insulin but hyperproinsulinaemia does not contribute appreciably to the elevated concentration of immunoreactive insulin in the peripheral circulation.
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Mukai J, Tanaka A, Ohta Y. Effect of ammonia on glucagon secretion from the perfused pancreas of cirrhotic rats. Diabetes Res Clin Pract 1986; 2:145-55. [PMID: 3527623 DOI: 10.1016/s0168-8227(86)80016-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Effects of ammonia on glucagon and insulin secretion from the perfused pancreas of cirrhotic rats were investigated to clarify the occurring mechanism of hypersecretion of pancreatic glucagon in liver cirrhotics. The results were as follows: During ammonia loading, insulin secretion was inhibited in a dose-related manner, whereas glucagon secretion was gradually increased at high concentrations of ammonia (2 mM) in control rats; this tendency was augmented in the presence of alpha-ketoglutarate in cirrhotic rats. On cessation of ammonia loading, a transient but definite increase in glucagon and insulin secretion was observed. Basal plasma glucagon and ammonia levels as well as basal glucagon secretion from the perfused pancreas of cirrhotic rats were significantly higher than in control rats. Basal insulin secretion from the perfused pancreas of cirrhotic rats was not different in spite of high levels of plasma insulin. Glucagon secretory response to glucose and arginine from the perfused pancreas of cirrhotic rats was higher than in the control pancreas, whereas insulin secretion was lower. In these cirrhotic rats, an increase in the number of islet cells, particularly A cells, was observed. These data suggested that hypersecretion of pancreatic glucagon which was responsible for hyperglucagonemia in cirrhotic rats might be attributed to high levels of ammonia and alpha-ketoglutarate in blood as well as to the fluctuation of abnormal ammonia concentration in blood and to the hypertrophy of islets, particularly of the A cell group due to hypersecretion.
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Verrillo A, de Teresa A, Martino C, Pinto M, Golia R. Circulating somatostatin concentrations in healthy and cirrhotic subjects. Metabolism 1986; 35:130-5. [PMID: 2868381 DOI: 10.1016/0026-0495(86)90113-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Plasma insulin, glucagon, somatostatin, and glucose concentrations were measured in the fasting state as well as after mixed meals (breakfast, lunch, and dinner) in 10 cirrhotic patients and 10 control subjects during a 24-hour period. Cirrhotic patients had fasting glucose values higher than controls (at -15 min: 5.2 +/- 0.2 mmol/L v 3.9 +/- 0.5 mmol/L, P less than 0.05; at 0 min: 5.5 +/- 0.3 mmol/L v 4.3 +/- 0.5 mmol/L, P less than 0.01). After meals blood glucose values remained higher in cirrhotics than in controls. Insulin levels did not differ between the groups in the fasting state, but cirrhotics showed a lower response to meals. Corresponding glucagon concentrations were greater in cirrhotics than in controls before and after meals throughout the 24-hour period (from -15 min to 24 hour: P less than 0.01). BAsal plasma somatostatin levels in the cirrhotic group were significantly higher than in control subjects (at -15 min and at 0 min: P less than 0.05) and further increased after meals. Plasma somatostatin was heterogeneous in normal and cirrhotic group, but the increase in its concentrations in patients with chronic liver disease was for the most part a consequence of elevations in the 1600 and 3500 molecular weight components. The half-life of exogenously infused somatostatin in cirrhotics was comparable to that of controls. These results indicate that in liver cirrhosis elevated levels of circulating somatostatin are associated with hyperglucagonemia and impaired insulin release. The high plasma somatostatin levels observed in cirrhotic patients are the result of hypersecretion of the D cell rather than impaired removal of the peptide.
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