Serum Levels of Incretin Hormones - GLP-1 and GIP in Patients with Type 1 Diabetes Mellitus

The glucagon-like peptide-1 (GLP-1) and the glucose- dependent Insulinotropic peptide (GIP) are natural incretin hormones, which are secreted respectively by the L- and K-cells of the intestinal mucosa in response to the physiological gastrointestinal glucose absorption. In patients with type 2 diabetes mellitus, the incretin effect is reduced, whereas the results in type 1 diabetes mellitus (T1DM) are heterogeneous, in some patients normal incretin response is observed.

Comparative analysis of the basal serum levels of the incretin hormones GLP-1 and GIP in patients with type 1 DM and in individuals without carbohydrate disorders.

The study included 27 patients with diagnosed T1DM and a control group of 39 individuals without carbohydrate disorders. All participants in the study were subjected to the following clinical measurements and laboratory tests - height, weight, bioimpedance analysis of body composition, fasting blood sugar (BS 0'), postprandial blood sugar (PPBS), glycated haemoglobin (HbA1c) in T1DM patients, total cholesterol (TC), HDL cholesterol (HDL chol), triglycerides (TG), transaminase (AST and ALT), basal serum levels of GLP-1 and GIP.

The serum levels of GIP in the patients with type T1DM were significantly higher, compared to the individuals without carbohydrate disorders (P<0.05), while there was no statistically significant difference in the GLP-1 levels.

The significantly higher GIP levels and the similar GLP-1 levels in our patients with type 1 DM, compared to the individuals without carbohydrate disorders, support the hypothesis of intact incretin effect in this type of diabetes mellitus Key Words: Glucagon-like peptide-1, Glucose-dependent insulinotropic peptide, Type 1 diabetes mellitus.