Antioxidant vitamins C and E improve endothelial function in children with hyperlipidemia: Endothelial Assessment of Risk from Lipids in Youth (EARLY) Trial.
BACKGROUND
Hyperlipidemia is associated with endothelial dysfunction, an early event in atherosclerosis and predictor of risk for future coronary artery disease. Epidemiological studies suggest that increased dietary intake of antioxidants reduces the risk of coronary artery disease. The purpose of this study was to determine whether antioxidant vitamin therapy improves endothelial function and affects surrogate biomarkers for oxidative stress and inflammation in hyperlipidemic children.


RESULTS
In a randomized, double-blind, placebo-controlled trial, the effects of antioxidant vitamins C (500 mg/d) and E (400 IU/d) for 6 weeks and the National Cholesterol Education Program Step II (NCEP-II) diet for 6 months on endothelium-dependent flow-mediated dilation (FMD) of the brachial artery were examined in 15 children with familial hypercholesterolemia (FH) or the phenotype of familial combined hyperlipidemia (FCH). Antioxidant vitamin therapy improved FMD of the brachial artery compared with baseline (P<0.001) without an effect on biomarkers for oxidative stress (autoantibodies to epitopes of oxidized LDL, F2-isoprostanes, 8-hydroxy-2'-deoxyguanosine), inflammation (C-reactive protein), or levels of asymmetric dimethylarginine, an endogenous inhibitor of nitric oxide.


CONCLUSIONS
Antioxidant therapy with vitamins C and E restores endothelial function in hyperlipidemic children. Early detection and treatment of endothelial dysfunction in high-risk children may retard the progression of atherosclerosis.
Engler
Marguerite M
MM
University of California, San Francisco, 2 Koret Way, Rm N631, San Francisco, Calif 94143-0610, USA. marguerite.engler@nursing.ucsf.edu
Engler
Mary B
MB
Malloy
Mary J
MJ
Chiu
Elisa Y
EY
Schloetter
Monique C
MC
Paul
Steven M
SM
Stuehlinger
Markus
M
Lin
Ken Y
KY
Cooke
John P
JP
Morrow
Jason D
JD
Ridker
Paul M
PM
Rifai
Nader
N
Miller
Elizabeth
E
Witztum
Joseph L
JL
Mietus-Snyder
Michele
M
D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use*; D001916:Brachial Artery / Q000503:physiopathology; D002648:Child; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006949:Hyperlipidemias / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D014664:Vasodilation; D014810:Vitamin E / Q000627:therapeutic use*
D000975:Antioxidants; D014810:Vitamin E; D001205:Ascorbic Acid