Meal-dependent Regulation of Circulating Glycated Insulin in Type 2 Diabetic Subjects

Abstract

There is mounting evidence that elevated circulating concentrations of glycated insulin play a role in insulin resistance in type 2 diabetes. This study evaluated the secretion of glycated insulin in response to enteral stimulation in type 2 diabetic subjects. Following a mixed meal (450 kcal; 44 % carbohydrate; 40 % fat; 16 % protein), glycated insulin rose 10-fold to peak (60 min) at 104.5 ± 25.0 pmol/l (p < 0.001), representing 22 % total circulating insulin. The response paralleled early rises in insulin and C-peptide, which peaked at 90 min and were more protracted. Maximum glucose concentrations were observed at 50 min. These data indicate that type 2 diabetic subjects exhibit a rapid meal-induced release of glycated insulin from readily releasable pancreatic beta-cell stores, which might contribute to impaired glucose homeostasis following enteral nutrition.

Key words

Glycated insulin - meal - type 2 diabetes

References

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