Supplementation with tomato juice increases plasma lycopene but does not alter susceptibility to oxidation of low-density lipoproteins from renal transplant recipients.
OBJECTIVE
Oxidative stress and susceptibility of low-density lipoproteins (LDL) to oxidation are increased in renal transplant recipients. The aim of this study was to determine the effect of dietary supplementation with tomato juice on plasma levels of the antioxidant lycopene, serum indices of lipid peroxidation (fluorescent lipid oxidation products (FLOP) and thiobarbituric acid-reacting substances (TBARS)) and the resistance of isolated low-density lipoprotein (LDL) to oxidation (lag time) in patients with a kidney graft.


METHODS
Fifteen patients were randomized to daily consumption of either tomato juice or synthetic orange drink for 4 weeks in a crossover study. Plasma lycopene levels were significantly higher (1.57 micromol/l versus 0.91 micromol/l, p = 0.015) while serum FLOP and TBARS and resistance of LDL to oxidation were not significantly different during supplementation with tomato juice compared with orange drink. At baseline, serum levels of lycopene and FLOP were abnormally high and serum FLOP was correlated significantly with plasma cyclosporine levels (r = 0.646, p = 0.016).


CONCLUSIONS
In conclusion, these data suggest that increased oxidative stress and susceptibility of LDL to oxidation may not be reduced by increasing plasma lycopene levels with regular consumption of tomato juice in renal transplant recipients.
Sutherland
W H
WH
Department of Medicine, University of Otago Medical School, Dunedin, New Zealand.
Walker
R J
RJ
De Jong
S A
SA
Upritchard
J E
JE
D000328:Adult; D000704:Analysis of Variance; D000975:Antioxidants / Q000378:metabolism*; D001628:Beverages; D002338:Carotenoids / Q000097:blood*; D002957:Citrus; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D016030:Kidney Transplantation / Q000502:physiology*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D000077276:Lycopene; D018551:Solanum lycopersicum; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D000975:Antioxidants; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; D002338:Carotenoids; D000077276:Lycopene