Liraglutide in the management of type 2 diabetes

The pathophysiology of type 2 diabetes has been attributed to the classic triad of decreased insulin secretion, increased insulin resistance, and elevated hepatic glucose production. Research has shown additional mechanisms, including incretin deficiency or resistance in the gastrointestinal tract. Liraglutide is a modified form of human glucagon-like peptide-1. Liraglutide was obtained by substitution of lysine 34 for arginine near the NH2 terminus, and by addition of a C16 fatty acid at the ɛ-amino group of lysine (at position 26) using a γ-glutamic acid spacer. Liraglutide has demonstrated glucose-dependent insulin secretion, improvements in β-cell function, deceleration of gastric emptying, and promotion of early satiety leading to weight loss. Liraglutide has the potential to acquire an important role, not only in the treatment of type 2 diabetes, but also in preservation of β-cell function, weight loss, and prevention of chronic diabetic complications

Effect of exenatide on splanchnic and peripheral glucose metabolism in type 2 diabetic subjects

OBJECTIVE: Our objective was to examine the mechanisms via which exenatide attenuates postprandial hyperglycemia in type 2 diabetes mellitus (T2DM). STUDY DESIGN: Seventeen T2DM patients (44 yr; seven females, 10 males; body mass index = 33.6 kg/m(2); glycosylated hemoglobin = 7.9%) received a mixed meal followed for 6 h with double-tracer technique ([1-(14)C]glucose orally; [3-(3)H]glucose i.v.) before and after 2 wk of exenatide. In protocol II (n = 5), but not in protocol I (n = 12), exenatide was given in the morning of the repeat meal. Total and oral glucose appearance rates (RaT and RaO, respectively), endogenous glucose production (EGP), splanchnic glucose uptake (75 g - RaO), and hepatic insulin resistance (basal EGP x fasting plasma insulin) were determined. RESULTS: After 2 wk of exenatide (protocol I), fasting plasma glucose decreased (from 10.2 to 7.6 mm) and mean postmeal plasma glucose decreased (from 13.2 to 11.3 mm) (P < 0.05); fasting and meal-stimulated plasma insulin and glucagon did not change significantly. After exenatide, basal EGP decreased (from 13.9 to 10.8 mumol/kg . min, P < 0.05), and hepatic insulin resistance declined (both P < 0.05). RaO, gastric emptying (acetaminophen area under the curve), and splanchnic glucose uptake did not change. In protocol II (exenatide given before repeat meal), fasting plasma glucose decreased (from 11.1 to 8.9 mm) and mean postmeal plasma glucose decreased (from 14.2 to 10.1 mm) (P < 0.05); fasting and meal-stimulated plasma insulin and glucagon did not change significantly. After exenatide, basal EGP decreased (from 13.4 to 10.7 mumol/kg . min, P = 0.05). RaT and RaO decreased markedly from 0-180 min after meal ingestion, consistent with exenatide\u27s action to delay gastric emptying. CONCLUSIONS: Exenatide improves 1) fasting hyperglycemia by reducing basal EGP and 2) postmeal hyperglycemia by reducing the appearance of oral glucose in the systemic circulation