Abstract:
Soybean lipoxygenase (SLO) (500-5000 units/ml), Fe(III)Cl3/ascorbate (5-100microM)
and hematin (5-100microM) induced oxidative modification of lipids present in micelles of
linoleic acid (0.5 mM), liposomes prepared from phospholipid extracts of bovine brain (2.5
mg/ml), and h-LDL (0.5 mg/ml). Oxidation of the lipid substrates was determined by the
formation of thiobarbituric acid reactive substances and conjugated dienes. Free iron
(Fe(III)Cl3/ascorbate) was the strongest initiator, followed by hematin and SLO.
Ketoconazole (KC) attenuated lipid oxidation in a concentration dependent manner at
pharmacologically relevant levels (25-100microM) in all three substrates. Pretreatment of liposomes and h-LDL with KC produced greater attenuation of lipid oxidation by the various initiators in comparison to free KC.
