Proinsulin levels in patients with pancreatic diabetes are associated with functional changes in insulin secretion rather than pancreatic β-cell area

Abstract

Introduction: Hyperproinsulinaemia has been reported in patients with type 2 diabetes. It is unclear whether this is due to an intrinsic defect in b-cell function or secondary to the increased demand on the b-cells. We investigated whether hyperproinsulinaemia is also present in patients with secondary diabetes, and whether proinsulin levels are associated with impaired b-cell area or function. Patients and methods: Thirty-three patients with and without diabetes secondary to pancreatic diseases were studied prior to pancreatic surgery. Intact and total proinsulin levels were compared with the pancreatic b-cell area and measures of insulin secretion and action. Results: Fasting concentrations of total and intact proinsulin were similar in patients with normal, impaired (including two cases of impaired fasting glucose) and diabetic glucose tolerance (PZ0.58 and PZ0.98 respectively). There were no differences in the total proinsulin/insulin or intact proinsulin/insulin ratio between the groups (PZ0.23 and PZ0.71 respectively). There was a weak inverse association between the total proinsulin/insulin ratio and pancreatic b-cell area (r

Misfolded proteins in Alzheimer's disease and type II diabetes

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Correlation between serum proinsulin levels and fatty liver: The Dynamics of Lifestyle and Neighborhood Community on Health Study

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