title: Studies on lipid peroxidation in rat liver nuclei and isolated nuclear membranes.
abstract: Non-enzymatic and enzymatically-driven lipid peroxidation processes were studied in rat liver nuclei and isolated nuclear membranes, by evaluating the formation of thiobarbituric acid-chromophore, free malondialdehyde, lipofuscin-like pigments, and the degradation of polyunsaturated fatty acids of the nuclear membrane lipids. The results obtained show that: (1) both non-enzymatic and enzymatically driven lipid peroxidation processes are operative in cell nuclei and isolated nuclear membranes; (2) only for isolated nuclear membranes, a good qualitative and up to a great extent quantitative correlation between malondialdehyde and lipofuscin-like pigment formation was obtained; (3) there is a qualitative but not quantitative correlation between malondialdehyde formation and polyunsaturated fatty acid degradation; (4) lipid peroxidation processes in isolated nuclear membranes and intact nuclei have an essentially identical kinetic behaviour. No statistical differences in the relative increases in the concentrations of malondialdehyde and lipofuscin-like pigments or in the degradation of polyunsaturated fatty acids were obtained, when the two systems were compared, except in the presence of NADPH-ADP-Fe3+, which induced a significantly larger degradation of polyunsaturated fatty acids in isolated nuclear membranes than in intact nuclei, and (5) no malondialdehyde-DNA fluorescent adduct formation was observed in any of the experimental groups studied, as inferred from the characteristics of the fluorescent spectra of lipofuscin-like pigments extracted from incubated nuclear preparations.
authors.affiliation: Department of Radiobiology, University of Stockholm, Sweden.
authors.forename: C E
authors.initials: CE
authors.lastname: Vaca
authors.forename: J
authors.initials: J
authors.lastname: Wilhelm
authors.forename: M
authors.initials: M
authors.lastname: Harms-Ringdahl
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D002467:Cell Nucleus / Q000032:analysis / Q000378:metabolism*; D002712:Chlorides; D002851:Chromatography, High Pressure Liquid; D005227:Fatty Acids / Q000032:analysis; D005231:Fatty Acids, Unsaturated / Q000032:analysis / Q000378:metabolism; D005290:Ferric Compounds / Q000494:pharmacology; D005296:Ferrous Compounds / Q000494:pharmacology; D007700:Kinetics; D008054:Lipid Peroxides / Q000378:metabolism*; D008055:Lipids / Q000032:analysis; D008062:Lipofuscin; D008099:Liver / Q000648:ultrastructure*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009249:NADP / Q000494:pharmacology; D009685:Nuclear Envelope / Q000032:analysis / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013858:Thiobarbiturates
chemical_list: D002712:Chlorides; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D005290:Ferric Compounds; D005296:Ferrous Compounds; D008054:Lipid Peroxides; D008055:Lipids; D008062:Lipofuscin; D013858:Thiobarbiturates; D008315:Malondialdehyde; D009249:NADP; D000244:Adenosine Diphosphate; C029684:thiobarbituric acid; D001205:Ascorbic Acid; C024555:ferric chloride