出版社：American Society for Biochemistry and Molecular Biology
摘要：Abdominal obesity is associated with a decreased plasma concentrationof HDL cholesterol and with qualitative modifications of HDL,such as triglyceride enrichment. Our aim was to determine, inisolated aorta rings, whether HDL from obese subjects can counteractthe inhibitory effect of oxidized low density lipoprotein (OxLDL)on endothelium-dependent vasodilation as efficiently as HDLfrom normolipidemic, lean subjects. Plasma triglycerides were74% higher (P < 0.005) in obese subjects compared with controls,and apolipoprotein A-I (apoA-I) and HDL cholesterol concentrationswere 12% and 17% lower (P < 0.05), respectively. HDL fromcontrol subjects significantly reduced the inhibitory effectof OxLDL on vasodilation [maximal relaxation (Emax) = 82.1 ±8.6% vs. 54.1 ± 8.1%; P < 0.0001], but HDL from obesesubjects had no effect (Emax = 47.2 ± 12.5% vs. 54.1± 8.1%; NS). In HDL from abdominally obese subjects comparedwith HDL from controls, the apoA-I content was 12% lower (P< 0.05) and the triglyceride-to-cholesteryl ester ratio was36% higher (P = 0.08)). Emax(OxLDL + HDL) was correlated withHDL apoA-I content and triglyceride-to-cholesteryl ester ratio(r = 0.36 and r = –0.38, respectively; P < 0.05). Weconclude that in abdominally obese subjects, the ability ofHDL to counteract the inhibitory effect of OxLDL on vascularrelaxation is impaired. This could contribute to the increasedcardiovascular risk observed in these subjects.Supplementary key words obesity • high density lipoprotein • oxidized low density lipoprotein • triglycerides • apolipoprotein A-I
Abbreviations: apoA-I, apolipoprotein A-I; Emax, maximal relaxation; eNOS, endothelial nitric oxide synthase; HOMA, homeostasis model assessment; NO, nitric oxide; OxLDL, oxidized low density lipoprotein; PAF-AH, platelet-activated factor-acetyl hydrolase; PON, paraoxonase
