title: Cytotoxicity of food preservatives in cultured rat hepatocytes loaded with linolenic acid.
abstract: We investigated the ability of eight food preservatives to induce lipid peroxidation in normal and alpha-linolenic acid (LNA)-loaded cultured rat hepatocytes. On the addition of sodium dehydroacetate (DHA-Na), potassium sorbate (SA-K) or thiabendazole (TBZ) to the cell culture, lipid peroxidation, assessed in terms of the production of malondialdehyde (MDA), was induced in LNA-loaded cells, but not in normal cells. At the low concentrations, induction of lipid peroxidation in LNA-loaded cells was highest with TBZ, whereas at high concentrations DHA-Na greatly induced lipid peroxidation. The occurrence of lipid peroxidation in LNA-loaded cells was accompanied by a decrease in cellular GSH levels with the three preservatives and by a decrease in cellular protein-SH levels with DHA-Na and TBZ. Furthermore, cell injury, measured by the release of LDH, was produced in LNA-loaded cells exposed to DHA-Na and SA-K. The addition of TBZ caused substantial cell injury in normal cells, and even greater injury in LNA-loaded cells. The prevention of lipid peroxidation in LNA-loaded hepatocytes by addition of an antioxidant, N,N'-diphenyl-p-phenylenediamine (DPPD) almost completely prevented DHA-Na- and SA-K-induced cell injury, and reduced TBZ-induced cell injury. The addition of diphenyl (DP), o-phenylphenol (OPP) or butyl p-hydroxybenzoate (BHB) caused severe cell injury, in association with a marked decrease in cellular levels of both of GSH and protein-SH in both groups of cells. However, lipid peroxidation was not detectable in either group of cells exposed to these preservatives. Sodium propionate (PA-Na) and sodium benzoate (BA-Na) had little effect on any cytotoxic parameter in either group of cells.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Hiroshima, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Sugihara
authors.forename: K
authors.initials: K
authors.lastname: Shimomichi
authors.forename: K
authors.initials: K
authors.lastname: Furuno
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D005520:Food Preservatives / Q000633:toxicity*; D005978:Glutathione / Q000187:drug effects / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013438:Sulfhydryl Compounds / Q000378:metabolism; D017962:alpha-Linolenic Acid / Q000378:metabolism*
chemical_list: D005520:Food Preservatives; D013438:Sulfhydryl Compounds; D017962:alpha-Linolenic Acid; D008315:Malondialdehyde; D007770:L-Lactate Dehydrogenase; D005978:Glutathione