title: The effects of glutathione and vitamin E on iron toxicity in isolated rat hepatocytes.
abstract: This study examined the acute toxicity of ferrous sulfate on rat hepatocyte suspensions, the correlation between lipid peroxidation and cell death, and the roles of glutathione and vitamin E in protecting against iron toxicity. Incubation with ferrous sulfate for 2 h produced lipid peroxidation, but did not decrease cell viability in the hepatocytes. When diethyl maleate (DEM) was added to deplete cellular glutathione concentrations, ferrous sulfate treatment (2.0-5.0 mM) did cause cell death and lipid peroxidation developed more extensively, suggesting that iron-mediated hepatotoxicity is influenced by glutathione content. Reduced glutathione (GSH), N-acetylcysteine (NAC) and alpha-tocopherol (vitamin E), alone and in combination, were added to hepatocyte suspensions in an attempt to protect cells against iron-induced damage. In iron-DEM-treated cells, GSH and NAC treatment increased viability by 43 and 36%, respectively, but only the combination of the two agents reduced lipid peroxidation (53% decrease). Vitamin E treatment reduced lipid peroxidation by 39% and also increased cell viability by 12%. The greatest protection against iron-induced lipid peroxidation occurred with the combination of GSH, NAC and vitamin E, which reduced lipid peroxidation by 94% in iron-treated cells, and by 98% in iron-DEM-treated cells. However, this combination did not prevent iron-induced cell death, although it did increase viability by 18%. These results suggest that iron-induced cell death may not be dependent upon lipid peroxidation, at least in short-term exposures. The results also suggest an interaction between GSH and vitamin E in protecting against lipid peroxidation.
authors.affiliation: Department of Pharmacology-Toxicology, Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA.
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Milchak
authors.forename: J
authors.initials: J
authors.lastname: Douglas Bricker
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005296:Ferrous Compounds / Q000633:toxicity*; D005978:Glutathione / Q000494:pharmacology*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D004338:Drug Combinations; D005296:Ferrous Compounds; D014810:Vitamin E; C020748:ferrous sulfate; D005978:Glutathione; D000111:Acetylcysteine