Vitamin E is protective against iron toxicity and iron-induced hepatic vitamin E depletion in mice.

This study examined the effect of excess dietary iron on liver function, iron and vitamin E status and the protective activity of vitamin E. Consumption of excess dietary iron (3000, 5000, 8000 mg iron/kg/diet) compared with consumption of the control diet (120 mg iron/kg diet) by weanling male CD-1 mice for 7 wk resulted in accumulation of iron in liver, increased relative liver weights and a reduction in hepatic vitamin E stores. The concentration of vitamin E in the liver was negatively correlated with dietary iron concentration (r = 0.998). Weekly administration of vitamin E (20 mg/kg, subcutaneously) prevented iron-induced liver damage without altering hepatic iron stores. Pretreatment of adult male CD-1 mice with a single subcutaneous dose of vitamin E (20 mg/kg body wt) 24 h prior to a lethal dose of iron (60 mg/kg, intraperitoneally) resulted in 100% protection. A similar dose of vitamin E given 5, 30 or 60 min (intravenously) after iron intoxication enhanced survival to 90, 70 and 80%, respectively, compared with the untreated control group. Vitamin E treatment 30 min after iron intoxication reduced mortality by 75% compared with intravenous treatment with 10 mg/kg of deferoxamine (Desferal). Data in this study indicate that vitamin E may be a useful antidote for iron toxicoses and that iron-induced depletion of vitamin E may play a role in the pathogenesis of iron toxicity.