Abstract

Objective: Hyperproinsulinemia in type 2 diabetic subjects has recently been accepted as an independent cardiovascular risk factor. Moreover, it has been confirmed that high proinsulin concentrations stimulate amylin secretion by pancreatic b-cells and amyloid accumulation within pancreatic islets leading to impairment of pancreatic islets secretory function. The association between sulfonylureas administration and secretory function of pancreatic b-cells, especially concerning insulin precursor peptides, is not sufficiently elucidated. Preliminary studies by our research group revealed that the fasting proinsulin serum concentration is significantly higher in type 2 diabetic patients treated with sulfonylureas than in a well-matched group treated with insulin only. Methods: A total of 101 subjects with type 2 diabetes were treated either with sulfonylureas (n = 32), with insulin (n = 40), with sulfonylureas + insulin (n = 17) or with diet alone (n = 12). Results: The basal secretory function in the four groups were comparable (C-peptide fasting serum level > 0.5 ng/l). An effect of fasting glycemia, long-term metabolic control (HbA_1c), postprandial hyperglycemia (1,5-anhydro-D-glucitol), insulin resistance (HOMA_IRscore) and diabetes duration on the fasting proinsulin serum level in the subjects treated could be excluded. Conclusion: The disproportionately high proinsulin levels are due to sulfonylureas therapy. The effect is independent of fasting glycemia, long-term metabolic control, postprandial hyperglycemia, diabetes duration and peripheral insulin resistance.

Author Details

Authors

• M. Dworacka
• M. Abramczyk
• H. Winiarska
• S. Kuczynski
• M. Borowska
• K. Szczawinska

Departments

• Department of Pharmacology, Poznan University of Medical Sciences, Poznan, Poland

Address

M. Dworacka Department of Pharmacology Poznan University of Medical Sciences Rokietnicka 5a str. 60-806 Poznan, Poland
Email: [email protected]

Citation