Effects of a high polyunsaturated fat diet and vitamin E supplementation on high-density lipoprotein oxidation in humans.
Oxidative modification of high-density lipoproteins (HDL) impairs several biologic functions critical to its role in reverse cholesterol transport. We therefore investigated the effect of dietary polyunsaturated fat and vitamin E on the kinetics of HDL oxidation. Ten subjects were fed sequentially: a baseline diet in which the major fat source was olive oil; a high polyunsaturated fat diet in which the major fat source was safflower oil; and the safflower oil diet plus 800 I.U. vitamin E per day. Plasma lipoprotein levels, vitamin E content, fatty acid composition, and oxidation lag time and rate were determined after 3 weeks on each diet. The polyunsaturated fat diet increased the mean HDL(2) lag time from 45.8+/-12.5 to 83.3+/-11.6 min with no change in oxidation rate. Addition of vitamin E further increased the HDL(2) lag time to 115.6+/-4.4 min and decreased the HDL(2) oxidation rate 10-fold. Neither the polyunsaturated diet alone nor the diet with vitamin E supplementation had any effect on HDL(3) oxidation. We conclude that under conditions of controlled dietary fat intake, a high polyunsaturated fat intake does not increase the oxidation susceptibility of HDL subfractions, and that in this setting, vitamin E supplementation reduces the oxidation susceptibility of HDL(2). These data suggest that antioxidants could influence HDL function in vivo.
Schnell
J W
JW
Section of Gastroenterology, Department of Internal Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
Anderson
R A
RA
Stegner
J E
JE
Schindler
S P
SP
Weinberg
R B
RB
D000328:Adult; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D019587:Dietary Supplements; D005227:Fatty Acids / Q000032:analysis / Q000378:metabolism; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects*; D008075:Lipoproteins, HDL / Q000032:analysis / Q000378:metabolism*; D011336:Probability; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014280:Triglycerides / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D008075:Lipoproteins, HDL; D014280:Triglycerides; D014810:Vitamin E