Vildagliptin Improves Endothelium-Dependent Vasodilatation in Type 2 Diabetes

OBJECTIVE: To investigate whether the dipeptidyl peptidase-4 inhibitor vildagliptin improves endothelium-dependent vasodilatation in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Sixteen subjects with type 2 diabetes (age 59.8 ± 6.8 years, BMI 29.1 ± 4.8 kg/m(2), HbA(1c) 6.97 ± 0.61) on oral blood glucose–lowering treatment were included. Participants received vildagliptin 50 mg b.i.d. or acarbose 100 mg t.i.d. for four consecutive weeks in a randomized, double-blind, cross-over design. At the end of each treatment period, we measured forearm vasodilator responses to intra-arterially administered acetylcholine (endothelium-dependent vasodilator) and sodium nitroprusside (endothelium-independent vasodilator). RESULTS: Infusion of acetylcholine induced a dose-dependent increase in forearm blood flow in the experimental arm, which was higher during vildagliptin (3.1 ± 0.7, 7.9 ± 1.1, and 12.6 ± 1.4 mL ⋅ dL(−1) ⋅ min(−1) in response to three increasing dosages of acetylcholine) than during acarbose (2.0 ± 0.7, 5.0 ± 1.2, and 11.7 ± 1.6 mL ⋅ dL(−1) ⋅ min(−1), respectively; P = 0.01 by two-way ANOVA). Treatment with vildagliptin did not significantly change the vascular responses to sodium nitroprusside. CONCLUSIONS: Four weeks’ treatment with vildagliptin improves endothelium-dependent vasodilatation in subjects with type 2 diabetes. This observation might have favorable cardiovascular implications.