Single-dose acarbose decreased glucose-dependent insulinotropic peptide and glucagon levels in Chinese patients with newly diagnosed type 2 diabetes mellitus after a mixed meal

BACKGROUND: Acarbose slows down the intestinal absorption of carbohydrates, but its effects on the secretion of incretins are still poorly known. This study aimed to examine the effects of single-dose acarbose on the secretion of incretins in patients with newly diagnosed type 2 diabetes mellitus (T2DM). METHODS: In this pilot study, twenty-three patients diagnosed with T2DM were randomly assigned to the oral glucose tolerance test (OGTT) group (n = 11) and the mixed meal test (MMT) group (n = 12). Fourteen subjects with normal OGTT were included as controls. Plasma glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic peptide (GIP) were measured at 0 (fasting), 15, 30, 60, 90, and 120 min after nutrient load. A week later, controls underwent MMT, the OGTT group underwent OGTT receiving 100 mg acarbose, and the MMT group underwent MMT receiving 100 mg acarbose. The same blood markers were measured again. RESULTS: No significant difference was observed in the OGTT group before and after administering acarbose. In the MMT group, postprandial levels of glucose (P < 0.01), insulin (P < 0.01), glucagon at 15 min (P < 0.05), glucagon area under the curve (AUC) (P < 0.05), GIP levels at 30 min (P < 0.05), and GIP AUC (P < 0.05) were decreased after receiving acarbose with a mixed meal, but GLP-1 levels and GLP-1 AUC did not change. CONCLUSIONS: Single-dose acarbose could reduce the secretion of GIP and glucagon after a mixed meal in patients with newly diagnosed T2DM. The influence of acarbose on incretin levels could be related to the types of carbohydrate being consumed. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trial Registry (Registration Number: ChiCTR-TRC-14004260, Date of Registration: 2014-01-19).