Abstract |
Insulin monotherapy can neither maintain normoglycemia in type 1 diabetes (T1D) nor prevent the long-term damage indicated by elevated glycation products in blood, such as glycated hemoglobin (HbA1c). Here we find that hyperglycemia, when unaccompanied by an acute increase in insulin, enhances itself by paradoxically stimulating hyperglucagonemia. Raising glucose from 5 to 25 mM without insulin enhanced glucagon secretion ∼two- to fivefold in InR1-G9 α cells and ∼18-fold in perfused pancreata from insulin-deficient rats with T1D. Mice with T1D receiving insulin treatment paradoxically exhibited threefold higher plasma glucagon during hyperglycemic surges than during normoglycemic intervals. Blockade of glucagon action with mAb Ac, a glucagon receptor (GCGR) antagonizing antibody, maintained glucose below 100 mg/dL and HbA1c levels below 4% in insulin-deficient mice with T1D. In rodents with T1D, hyperglycemia stimulates glucagon secretion, up-regulating phosphoenolpyruvate carboxykinase and enhancing hyperglycemia. GCGR antagonism in mice with T1D normalizes glucose and HbA1c, even without insulin.
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Authors | May-Yun Wang, Hai Yan, Zhiqing Shi, Matthew R Evans, Xinxin Yu, Young Lee, Shiuhwei Chen, Annie Williams, Jacques Philippe, Michael G Roth, Roger H Unger |
Journal | Proceedings of the National Academy of Sciences of the United States of America
(Proc Natl Acad Sci U S A)
Vol. 112
Issue 8
Pg. 2503-8
(Feb 24 2015)
ISSN: 1091-6490 [Electronic] United States |
PMID | 25675519
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
- Antibodies, Monoclonal
- Blood Glucose
- Insulin
- Receptors, Glucagon
- Glucagon
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Topics |
- Animals
- Antibodies, Monoclonal
(pharmacology, therapeutic use)
- Blood Glucose
(metabolism)
- Diabetes Mellitus, Experimental
(blood, drug therapy, pathology)
- Diabetes Mellitus, Type 1
(blood, drug therapy, pathology)
- Female
- Glucagon
(metabolism)
- Humans
- Insulin
(therapeutic use)
- Mice
- Mice, Inbred NOD
- Paracrine Communication
(drug effects)
- Rats
- Rats, Zucker
- Receptors, Glucagon
(immunology)
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