Microvascular Endothelial Dysfunction in Patients with Obesity

Purpose of Review: To examine the state of the art on the pathogenesis of endothelial dysfunction in the microcirculation of patients with obesity, focusing on the complex relationship between the consolidated and the novel mechanisms involved in this alteration. Recent Findings: Human obesity is associated with vascular endothelial dysfunction, caused by a reduced nitric oxide availability secondary to an enhanced oxidative stress production. Pro-inflammatory cytokine generation, secreted by perivascular adipose tissue, is a major mechanism whereby obesity is associated with a reduced vascular NO availability. Vasculature also represents a source of low-grade inflammation and oxidative stress which contribute to endothelial dysfunction in obese patients. Recently, a direct influence of arginase on endothelial function by reducing nitric oxide availability was demonstrated in small vessels from patients with severe obesity. This effect is modulated by ageing and related to the high levels of vascular oxidative stress. Summary: Oxidative stress, inflammation, and enzymatic pathways are important players in the pathophysiology of obesity-related vascular disease. The identification of new therapeutic approaches able to interfere with these mechanisms will result in more effective prevention of the cardiovascular complications associated with obesity.