Study of the serum level of fasting glucagon-like peptide-1 in type 2 diabetics and its relation to the glycemic profile

Abstract

Glucagon-like peptide-1 (GLP-1) is a peptide formed of 30 amino acids. It is synthesized in and released from the enteroendocrine L cells that are present throughout the small and the large intestine. Because of the important physiological role of GLP-1 in augmenting insulin secretion, it is generally believed that GLP-1 release is deficient in type 2 diabetes mellitus (T2DM) patients. However, studies in adults have yielded conflicting results showing decreased, normal, or increased GLP-1 concentrations in prediabetics or T2DM after oral glucose or mixed meal. The aim of this work was to study the level of fasting total GLP-1 in T2DM patients and its relation to the glycemic profile. This study included 60 T2DM patients and 40 participants matched for age and sex as a control group, selected from the inpatient and outpatient clinics of the Internal Medicine Department in Menoufia University Hospital. After obtaining their informed consent, all participants were subjected to a full assessment of history and physical examination with estimation of BMI, insulin resistance with homeostasis model assessment-2, and investigations including fasting blood glucose (FBG), glycated hemoglobin (HbAIc), and the total fasting levels of GLP-1. There was no significant difference in the level of GLP-1 between T2DM patients and the controls. There were significant negative correlations between the fasting total GLP-1 and FBG, HbAIc, serum insulin, and homeostasis model assessment-2 in both the total sample and the T2DM patients. Fasting total levels of GLP-1 are not reduced in T2DM patients and are negatively correlated with FBG, HbAIc, and insulin resistance.