title: Mechanisms of high-density lipoprotein cholesterol effects on the endothelial function in hyperlipemia.
abstract: High-density lipoprotein-cholesterol (HDL-c) has a favorable influence on the endothelial function, but the mechanisms of this protective action are not fully understood. We studied lipid parameters, soluble adhesion molecules (vascular cell adhesion molecule-1 [VCAM-1], intercellular adhesion molecule [ICAM-1], E-selectin) oxidized low-density lipoproteins (LDL), and brachial-artery flow-mediated vasodilation (FMV) in 184 hyperlipemic patients (90 men, age 54 +/- 10 years, waist/hip circumference ratio 0.89 +/- 0.07, LDL-cholesterol [LDL-c] 4.9 +/- 1.3 mmol/L, triglycerides 1.8 +/- 0.9 mmol/L, HDL-c 1.3 +/- 0.5 mmol/L) after excluding those with current smoking, diabetes, hypertension, and vascular diseases. Patients were divided into 2 groups on the basis of HDL-c levels: < 1.03 mmol/L (n = 53) v >or= 1.03 mmol/L (n = 131). Patients with low HDL-c showed significantly lower LDL-c (P <.05), higher triglycerides (P <.001), higher body mass index (P <.02), lower FMV (3.7% +/- 2.0% v 4.9% +/- 3.4%, P <.002), higher VCAM-1 (1,195 +/- 395 ng/mL v 984 +/- 303 ng/mL, P <.01), and higher ICAM-1 (406 +/- 78 ng/mL v 364 +/- 68 ng/mL, P <.01). E-selectin and oxidized LDL showed no significant differences. In a multivariate age, oxidized LDL and brachial artery diameter predicted a lower FMV, while HDL-c was an independent predictor of a greater FMV (P =.003). Increasing levels of VCAM-1 and ICAM-1 were predicted by lower HDL-c, while higher oxidized LDL predicted higher VCAM-1 (P <.05). Our data suggest that in hyperlipemic subjects free of cardiovascular disease low HDL-c negatively modulates endothelial function through a lack of oxidation inhibition and a concomitant overexpression of adhesion molecules.
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D015992:Body Mass Index; D001916:Brachial Artery / Q000503:physiopathology; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood; D019040:E-Selectin / Q000097:blood; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood / Q000503:physiopathology*; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood; D019010:Vascular Cell Adhesion Molecule-1 / Q000097:blood; D014664:Vasodilation
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D019040:E-Selectin; D008077:Lipoproteins, LDL; D014280:Triglycerides; D019010:Vascular Cell Adhesion Molecule-1; C099252:oxidized low density lipoprotein; D018799:Intercellular Adhesion Molecule-1