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Steenberg VR, Jensen SM, Pedersen J, Madsen AN, Windeløv JA, Holst B, Quistorff B, Poulsen SS, Holst JJ. Acute disruption of glucagon secretion or action does not improve glucose tolerance in an insulin-deficient mouse model of diabetes. Diabetologia 2016; 59:363-70. [PMID: 26537124 DOI: 10.1007/s00125-015-3794-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 09/29/2015] [Indexed: 12/25/2022]
Abstract
AIMS/HYPOTHESIS Normal glucose metabolism depends on pancreatic secretion of insulin and glucagon. The bihormonal hypothesis states that while lack of insulin leads to glucose underutilisation, glucagon excess is the principal factor in diabetic glucose overproduction. A recent study reported that streptozotocin-treated glucagon receptor knockout mice have normal glucose tolerance. We investigated the impact of acute disruption of glucagon secretin or action in a mouse model of severe diabetes by three different approaches: (1) alpha cell elimination; (2) glucagon immunoneutralisation; and (3) glucagon receptor antagonism, in order to evaluate the effect of these on glucose tolerance. METHODS Severe diabetes was induced in transgenic and wild-type mice by streptozotocin. Glucose metabolism was investigated using OGTT in transgenic mice with the human diphtheria toxin receptor expressed in proglucagon producing cells allowing for diphtheria toxin (DT)-induced alpha cell ablation and in mice treated with either a specific high affinity glucagon antibody or a specific glucagon receptor antagonist. RESULTS Near-total alpha cell elimination was induced in transgenic mice upon DT administration and resulted in a massive decrease in pancreatic glucagon content. Oral glucose tolerance in diabetic mice was neither affected by glucagon immunoneutralisation, glucagon receptor antagonism, nor alpha cell removal, but did not deteriorate further compared with mice with intact alpha cell mass. CONCLUSIONS/INTERPRETATION Disruption of glucagon action/secretion did not improve glucose tolerance in diabetic mice. Near-total alpha cell elimination may have prevented further deterioration. Our findings support insulin lack as the major factor underlying hyperglycaemia in beta cell-deficient diabetes.
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Affiliation(s)
- Vivi R Steenberg
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Signe M Jensen
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Jens Pedersen
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Andreas N Madsen
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Johanne A Windeløv
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Birgitte Holst
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Bjørn Quistorff
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Steen S Poulsen
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark
| | - Jens J Holst
- Section for Translational Metabolic Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, building 12.2, DK-2200, Copenhagen, Denmark.
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