Serum bile acid response to oral glucose is attenuated in patients with early type 2 diabetes and correlates with 2‐hour plasma glucose in individuals without diabetes

AIM: To determine the serum bile acid (BA) response to 75‐g oral glucose in individuals without diabetes, and whether this is attenuated in patients with ‘early’ type 2 diabetes (T2D) and related to the glycaemic response at 2 hours in either group. METHODS: Forty newly diagnosed, treatment‐naïve Han Chinese T2D subjects and 40 age‐, gender‐, and body mass index‐matched controls without T2D ingested a 75‐g glucose drink after an overnight fast. Plasma glucose and serum concentrations of total and individual BAs, fibroblast growth factor‐19 (FGF‐19), total glucagon‐like peptide‐1 (GLP‐1), and insulin, were measured before and 2 hours after oral glucose. RESULTS: Fasting total BA levels were higher in T2D than control subjects (P < .05). At 2 hours, the BA profile exhibited a shift from baseline in both groups, with increases in conjugated BAs and/or decreases in unconjugated BAs. There were increases in total BA and FGF‐19 levels in control (both P < .05), but not T2D, subjects. Plasma glucose concentrations at 2 hours related inversely to serum total BA levels in control subjects (r = −0.42, P = .006). Total GLP‐1 and the insulin/glucose ratio were increased at 2 hours in both groups, and the magnitude of the increase was greater in control subjects. CONCLUSIONS: The serum BA response to a 75‐g oral glucose load is attenuated in patients with ‘early’ T2D, as is the secretion of FGF‐19 and GLP‐1, while in individuals without T2D it correlates with 2‐hour plasma glucose levels. These observations support a role for BAs in the regulation of postprandial glucose metabolism.