Telmisartan decreases plasma levels of asymmetrical dimethyl-L-arginine and improves lipid and glucose metabolism and vascular function

Abstract

Telmisartan is an angiotensin II receptor blocker (ARB) and also an activator of peroxisome proliferator-activated receptor-γ (PPAR-γ). We investigated whether telmisartan improves vascular endothelial function in patients with essential hypertension with the production of endothelial nitric oxide synthase (eNOS) through PPAR-γ. Telmisartan was administered to 15 patients with essential hypertension. To assess vascular function, asymmetric dimethylarginine (ADMA), an eNOS inhibitor synthesized by endothelial cells, and the pulse-wave velocity (PWV) were measured. The serum levels of lipid, glucose, and glycohemoglobin (HbA1c) were also evaluated before and after treatment. Telmisartan therapy significantly decreased the blood pressure and to total- and LDL-choleslerol levels. HbA1c was also significantly improved but not in fasting plasma glucose. The serum levels of ADMA were significantly decreased (0.48 ± 0.08 to 0.42 ± 0.05 nmol/mL; P = 0.01). PWV values were significantly decreased by telmisartan from 1,822.5 ± 352.3 to 1,661.5 ± 299.8 cm/second (P = 0.04*). Telmisartan decreased PWV presumably via the activation of PPAR-γ, suggesting that this agent improves vascular endothelial function via its pleiotropic effects, a mechanism that is different from its hypotensive effects.