Effect of a single high-fat meal on endothelial function in healthy subjects.
Although there is a well-established relation between serum cholesterol and coronary artery disease risk, individual and national variations in this association suggest that other factors are involved in atherogenesis. High-fat diet associated triglyceride-rich lipoproteins have also been suggested to be atherogenic. To assess the direct effect of postprandial triglyceride-rich lipoproteins on endothelial function, an early factor in atherogenesis--10 healthy, normocholesterolemic volunteers--were studied before and for 6 hours after single isocaloric high- and low-fat meals (900 calorie; 50 and 0 g fat, respectively). Endothelial function, in the form of flow-mediated vasoactivity, was assessed in the brachial artery using 7.5-MHz ultrasound as percent arterial diameter change 1 minute after 5 minutes of upper-arm arterial occlusion. Serum lipoproteins and glucose were determined before eating and 2 and 4 hours postprandially. Serum triglycerides increased from 94 +/- 55 mg/dl preprandially to 147 +/- 80 mg/dl 2 hours after the high-fat meal (p = 0.05). Flow-dependent vasoactivity decreased from 21 +/- 5% preprandially to 11 +/- 4%, 11 +/- 6%, and 10 +/- 3% at 2, 3, and 4 hours after the high-fat meal, respectively (all p <0.05 compared with low-fat meal data). No changes in lipoproteins or flow-mediated vasoactivity were observed after the low-fat meal. Fasting low-density lipoprotein cholesterol correlated inversely (r = -0.47, p = 0.04) with preprandial flow-mediated vasoactivity, but triglyceride level did not. Mean change in postprandial flow-mediated vasoactivity at 2, 3, and 4 hours correlated with change in 2-hour serum triglycerides (r = -0.51, p = 0.02). These results demonstrate that a single high-fat meal transiently impairs endothelial function. These findings identify a potential process by which a high-fat diet may be atherogenic independent of induced changes in cholesterol.
Vogel
R A
RA
Department of Medicine, University of Maryland School of Medicine, Baltimore 21201-2595, USA.
Corretti
M C
MC
Plotnick
G D
GD
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D001916:Brachial Artery / Q000000981:diagnostic imaging; D015986:Confounding Factors, Epidemiologic; D004041:Dietary Fats / Q000008:administration & dosage / Q000009:adverse effects*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006339:Heart Rate; D006801:Humans; D008074:Lipoproteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D014463:Ultrasonography
D001786:Blood Glucose; D004041:Dietary Fats; D008074:Lipoproteins