Effects of Luseogliflozin on the Secretion of Islet Hormones and Incretins in Patients with Type 2 Diabetes

The insufficient activity of insulin and the hyperactivity of glucagon are responsible for glucose intolerance in patients with type 2 diabetes. Whereas sodium-glucose cotransporter-2 (SGLT2) inhibitors improve blood glucose levels in patients with type 2 diabetes, their effects on the secretion profiles of glucagon and incretins remain unclear. Therefore, to investigate the effects of the SGLT2 inhibitor luseogliflozin on metabolic and endocrine profiles, 19 outpatients with type 2 diabetes were administered luseogliflozin for 12 weeks. It is of note that all subjects were treated only with diet and exercise therapy, and we were able to investigate the effects of luseogliflozin separately from the effects of other antidiabetic agents. Body weight, body fat mass, fat-free mass, and muscle mass were significantly reduced after 12 weeks of luseogliflozin administration. Glycosylated hemoglobin significantly decreased from the baseline of 8.2% ± 0.8% to 7.3% ± 0.7% (p < 0.0001). The meal tolerance test demonstrated that luseogliflozin significantly recovered glucose tolerance, accompanied by improved insulin resistance and β-cell function, whereas glucagon secretion was unaffected. Furthermore, GLP-1 secretion was significantly increased after luseogliflozin administration. Thus, luseogliflozin improved metabolic and endocrine profiles accompanied by increased GLP-1 secretion in type 2 diabetic patients without any antidiabetic medication, but did not affect glucagon secretion.