title: Lipid peroxidation and irreversible cell damage: synergism between carbon tetrachloride and 1,2-dibromoethane in isolated rat hepatocytes.
abstract: The combination of 1,2-dibromoethane (DBE) with carbon tetrachloride (CCl4) in the isolated rat hepatocyte model produces a significant potentiation of both lipid peroxidation and plasma membrane damage induced by the latter compound. The increase in malondialdehyde production precedes the hepatocyte damage, evaluated in terms both of lactate dehydrogenase leakage and trypan blue exclusion. When hepatocytes are isolated from vitamin E pretreated rats, both the prooxidant and the cytotoxic effects of CCl4 are prevented. Also the synergism between CCl4 and DBE on lipid peroxidation disappears completely while that on cell damage is strongly reduced. The increased lipid peroxidation appears to be one of the mechanisms of the observed synergism between CCl4 and DBE on hepatocyte damage. Regarding the antioxidant status of the hepatocyte challenged with CCl4 and DBE, an early and significant consumption of vitamin E is observed only in the presence of the mixture of these xenobiotics. Total nonprotein thiol content is not significantly modified by CCl4 poisoning while DBE, alone and in association with CCl4, markedly decreases it. Vitamin E supplementation does not prevent but moderately delays total nonprotein thiol depletion due to DBE or to the mixture. Finally, glutathione transferase activity is significantly reduced by CCl4 treatment and not by DBE, and vitamin E supplementation totally prevents such inhibition. The increased prooxidant effect of CCl4 plus DBE compared to CCl4 alone seems related to the shift in DBE metabolism consequent to the CCl4-dependent inactivation of glutathione transferase.
authors.affiliation: Dipartimento di Medicina ed Oncologia Sperimentale, Sezione di Patologia Generale, Torino, Italy.
authors.forename: O
authors.initials: O
authors.lastname: Danni
authors.forename: E
authors.initials: E
authors.lastname: Chiarpotto
authors.forename: M
authors.initials: M
authors.lastname: Aragno
authors.forename: F
authors.initials: F
authors.lastname: Biasi
authors.forename: A
authors.initials: A
authors.lastname: Comoglio
authors.forename: F
authors.initials: F
authors.lastname: Belliardo
authors.forename: M U
authors.initials: MU
authors.lastname: Dianzani
authors.forename: G
authors.initials: G
authors.lastname: Poli
mesh_terms: D000818:Animals; D002251:Carbon Tetrachloride / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004357:Drug Synergism; D015946:Ethylene Dibromide / Q000494:pharmacology*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008099:Liver / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology
chemical_list: D014810:Vitamin E; D015946:Ethylene Dibromide; D008315:Malondialdehyde; D002251:Carbon Tetrachloride; D007770:L-Lactate Dehydrogenase; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005982:Glutathione Transferase