Microvascular endothelial dysfunction in obesity and hypertension.

Endothelium plays a crucial role in modulating vascular function and structure, mainly by production of nitric oxide which protects the vasculature against the development of atherosclerosis and thrombosis. Traditional cardiovascular risk factors are characterized by endothelial dysfunction caused by an enhanced production of oxidative stress leading to destroy NO thus reducing its availability. A reduced endothelium-dependent relaxation is a predictor of cardiovascular events in high risk patients. Abdominal obesity is associated with microvascular endothelial dysfunction, through indirect mechanisms, such as insulin-resistance and the association with risk factors (including diabetes mellitus, hypertension and dyslipidemia), and directly, among others, by the production of adipokines and pro-inflammatory cytokines which in turn induce oxidative stress leading to a reduced NO availability. Several systems are amplified by the concomitant obesity and hypertension, thus generating a perpetual vicious circle which further contribute to the pathogenesis/progression of microvascular disease. Weight loss and modification of life-style ameliorate endothelial function in obese patients. It is conceivable that endothelial dysfunction might represent a complementary but crucial objective of a modern therapeutical approach leading to improve the prognosis in many patients, including obese patients, exposed to a high cardiovascular risk.