Glucagon receptor antibody completely suppresses type 1 diabetes phenotype without insulin by disrupting a novel diabetogenic pathway

MY Wang, H Yan, Z Shi, MR Evans… - Proceedings of the …, 2015 - National Acad Sciences
MY Wang, H Yan, Z Shi, MR Evans, X Yu, Y Lee, S Chen, A Williams, J Philippe, MG Roth
Proceedings of the National Academy of Sciences, 2015National Acad Sciences
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 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.
National Acad Sciences