The synergistic effects of vitamin E and selenium in iron-overloaded mouse hearts.
OBJECTIVE
To determine whether supplementation with vitamin E and selenium can improve myocardial antioxidant defenses in iron-overloaded mouse hearts.


METHODS
Iron-overload state was created in B6D2F1 mice (n = 20) by daily injection of iron dextran (5 mg intraperitoneally/mouse) for four weeks. The mice were also simultaneously randomly assigned to receive vitamin E (alpha-tocopherol acetate, 40 mg intraperitoneally, n = 5), selenium (sodium selenite, 1 part/million orally, n = 5), both (vitamin E + selenium, n = 5) or iron-only treatment (n = 5). The hearts were harvested for determination of selenium concentration and glutathione peroxidase activity. In a subsequent study, 15 B6D2F1 mice were randomly assigned to receive daily injections of iron (n = 5) or iron and combined antioxidant treatment (vitamin E + selenium, n = 5), or to serve as controls (n = 5) for four weeks. The hearts were harvested for determination of total iron concentrations.


RESULTS
Significantly greater concentrations of heart selenium and glutathione peroxidase activity were observed in groups supplemented with both agents, as opposed to iron-only treated or single supplemented mice. Significantly lower concentrations of iron were found in controls and in those receiving combined iron and antioxidant treatment (vitamin E + selenium) than in iron-only treated mice.


CONCLUSIONS
Vitamin E and selenium function synergistically in the myocardium to provide important antioxidant defenses in iron-overload states, including increased concentrations of selenium, increased glutathione peroxidase activity and decreased concentrations of iron.
Centre For Cardiovascular Research, Toronto Hospital, Ontario.
W J
WJ
Bartfay
D
D
Hou
G M
GM
Brittenham
E
E
Bartfay
M J
MJ
Sole
D
D
Lehotay
P P
PP
Liu
D000818:Animals; D009202:Cardiomyopathies / Q000139:chemically induced / Q000188:drug therapy*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D062787:Drug Overdose; D004357:Drug Synergism; D006321:Heart / Q000187:drug effects; D006801:Humans; D007501:Iron / Q000008:administration & dosage* / Q000009:adverse effects; D051379:Mice; D012643:Selenium / Q000008:administration & dosage* / Q000494:pharmacology; D014810:Vitamin E / Q000008:administration & dosage* / Q000494:pharmacology
D014810:Vitamin E; D007501:Iron; D012643:Selenium