High-Density Lipoprotein Cholesterol Affects Early Endothelial Progenitor Cell Number and Endothelial Function in Obese Women

Objective: In order to improve our understanding of high-density lipoprotein cholesterol (HDL-C) cardiovascular (CV) impact in obesity, the association of HDL-C plasma level with circulating early endothelial progenitor cell (early-EPC) number and endothelium-dependent vasodilatation (EDV) in obese women with normal or high low-density lipoprotein cholesterol (LDL-C) plasma levels was evaluated. Design and Methods: One hundred thirteen obese female subjects and a control group of 78 healthy female subjects were recruited. Circulating early-EPC were assessed by single-and two-color flow cytometric analyses with a fluorescence activated cell sorting (FACScan) flow cytometer. EDV was evaluated as response to ischemia by strain gauge plethysmography. Results: Both early-EPC number and EDV were significantly decreased in obese women compared with the control group. Obese women with low HDL-C showed a further decrease of early-EPC and EDV in the presence of both high or normal LDL-C plasmatic levels. In the normal HDL-C level subgroup, hypercholesterolemic and nonhypercholesterolemic subjects showed no difference in early-EPC number, whereas slight EDV impairment was present in hypercholesterolemic subjects. Conclusion: In obese women, low HDL-C is associated to decreased early-EPC number and impaired EDV, suggesting the need to assess whether evaluation of early-EPC and EDV may increase HDL-C prognostic value in the stratification of CV risk.