Regulation of glucagon secretion by incretin-like hormone family in the patients at risk of developing type 2 diabetes mellitus

Abstract

The study included 127 patients with type 2 diabetes (T2D) risk factors, who underwent oral glucose tolerance test (75 g glucose) with pancreatic and incretin hormones estimated in fasting state, at 30 and 120 minutes after glucose load. According to the test results the population was divided into 3 groups: group with normal glucose tolerance (NGT), group with high risk of diabetes developing (impaired glucose tolerance (IGT) and impaired fasting glycemia (IFG)) and newly-diagnosed T2D. The stimulated glucagon secretion was suppressed in NGT group, whereas in T2D patients there was an increase in glucagon levels at 30 min after the glucose load. Within high risk group the area under curve (AUC) of glucagon secretion was significantly elevated in IFG patients comparing to IGT (0,52 vs 0,07 ng·ml-1·min-1, р=0,0005). AUC of glucagon secretion was positively related only to fasting glucagon-like peptide 2 (GLP-2) level (r=0,61, р=0,0001), that suggests glucagonotropic properties for GLP-2. We conclude that glucagon stimulation by GLP-2 may play a role in decreased glucagon suppression in T2D patients and IFG state development.