9. Ferric ion-induced lipid peroxidation
in erythrocyte membranes: effects of phytic acid and butylated hydroxytoluene.
Ko KM, Godin DV.
Department of Pharmacology & Therapeutics, Faculty of Medicine, University of British
Columbia, Vancouver,
Canada.
Ferric ion was found to stimulate the peroxidation of
erythrocyte membrane lipids, causing a biphasic and concentration-dependent
increase in the formation of thiobarbituric acid
reactive substances. Ascorbic acid and reduced glutathione were able to enhance
this lipid peroxidation, presumably by facilitating
the reduction of ferric ion. Iron chelators, such as phytic acid, ethylenediaminetetraacetic
acid and uric acid, and the chain-reaction-terminating antioxidant butylated hydroxytoluene
suppressed the ferric ion-induced peroxidation by
actions not likely related to hydroxyl radical scavenging. The effectiveness of
phytic acid, a naturally occurring antioxidant, in
the inhibition of iron-dependent lipid peroxidation
suggests its possible therapeutic application as a non-toxic iron chelator for ameliorating the extent of oxy-radical-induced
tissue damage.