Effect of antioxidants on lipid peroxidation in iron-loaded rats.
Indirect evidence has suggested that lipid peroxidation is associated with iron overload in vivo. As a measure of lipid peroxidation, pentane expired in the breath of rats loaded with an accumulated dose of either 100 mg or 186-200 mg of iron injected intraperitoneally as iron dextran was measured over a 7 to 8 week period, and the effect on pentane production of feeding antioxidant-supplemented diets was determined. By the seventh week of feeding the diets, rats fed 0.3% L-ascorbic acid produced 17% less (P = 0.03) pentane than did rats fed the basal antioxidant-deficient diet, whereas rats fed 0.004% dl-alpha-tocopherol acetate produced 92% less (P less than 0.001). After being fed the basal diet for 7 weeks, iron-loaded rats produced 76 +/- 9 pmol pentane/100 g body wt/min. When synthetic antioxidants were added to the diet at a concentration of 0.25%, the order of effectiveness in decreasing pentane production after 1 week was: N,N'-diphenyl-p-phenylenediamine greater than ethoxyquin greater than butylated hydroxyanisole greater than butylated hydroxytoluene greater than propyl gallate approximately equal to no antioxidant. After removal of either ethoxyquin or N,N'-diphenyl-p-phenylenediamine from the diets for 1 week, pentane production increased to a high level. The total amount of lipid soluble fluorophores in individual spleens of rats fed N,N'-diphenyl-p-phenylenediamine, ethoxyquin, dl-alpha- tocopherol acetate, ascorbic acid and no antioxidant were correlated significantly with the corresponding total integrated amount of pentane produced by the individual rats over the 7 to 8 week period. This study has provided some of the most direct evidence to date that lipid peroxidation is associated with iron overload in vivo.
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D002849:Chromatography, Gas / Q000379:methods; D005453:Fluorescence; D007501:Iron / Q000506:poisoning*; D008054:Lipid Peroxides / Q000096:biosynthesis*; D008297:Male; D010420:Pentanes / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000378:metabolism; D013997:Time Factors; D014810:Vitamin E / Q000494:pharmacology
D000975:Antioxidants; D008054:Lipid Peroxides; D010420:Pentanes; D014810:Vitamin E; D007501:Iron; D001205:Ascorbic Acid