Measuring the oxidation of heme compounds in heart homogenates from rats supplemented with dietary antioxidants.
Protection by antioxidant nutrients against oxidative damage in rat heart homogenates was studied. Following spontaneous oxidation of heart homogenates from rats fed vitamin E, selenium, or beta-carotene, oxidized heme proteins (OHP) and thiobarbituric acid reactive substances (TBARS) were measured. The absorbance spectra of oxidized and reduced heme proteins were analyzed with a heme spectral analysis program (HSAP) developed in this laboratory. HSAP is a multicomponent analysis program that uses successive approximations and computer spread-sheet solver functions to deconvolute a complex absorbance spectrum into individual heme protein spectra. Vitamin E markedly decreased formation of OHP, and vitamin E, selenium, or beta-carotene significantly lowered the production of TBARS during spontaneous oxidation of heart homogenates compared with homogenates from rats fed antioxidant-deficient diets. Pyridine hemochrome analysis showed that the total amounts of heme proteins present in the homogenates decreased during the oxidative incubation period. The formation of OHP correlated significantly with the amount of TBARS produced and could be simulated as a function of the oxidative and protective reactions involved in the oxidation of rat heart homogenates.
North
J A
JA
Department of Food Science and Technology, University of California, Davis 95616, USA.
Tappel
A L
AL
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001665:Binding Sites; D004032:Diet; D005609:Free Radicals; D005979:Glutathione Peroxidase / Q000378:metabolism; D006420:Hemeproteins / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D012643:Selenium / Q000494:pharmacology; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000494:pharmacology; D019207:beta Carotene / Q000494:pharmacology
D000975:Antioxidants; D005609:Free Radicals; D006420:Hemeproteins; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D019207:beta Carotene; D014810:Vitamin E; D005979:Glutathione Peroxidase; D012643:Selenium