Characterization of glutathione-dependent inhibition of lipid peroxidation of isolated rat liver nuclei.
Glutathione (GSH) is known to play an important role in protecting cells against oxidative stress. The present study was undertaken to assess the ability of GSH to protect isolated rat liver nuclei against NADPH-induced peroxidation. Nuclei were isolated from rat liver homogenates by discontinuous sucrose gradient centrifugation, and lipid peroxidation was induced by 1.7 mM ADP, 0.11 mM EDTA, 0.1 mM FeCl3, and either 1 mM NADPH or 0.5 mM ascorbate. The amount of lipid peroxidation was determined by measuring the formation of thiobarbituric acid-reactive products and the disappearance of lipid unsaturated fatty acid moieties. The addition of GSH (0.1 to 1.0 mM) produced a concentration-dependent lag period prior to the onset of lipid peroxidation. This GSH-induced lag period was abolished by pretreatment of nuclei with trypsin, thiol modifying reagents, disulfides, or heating nuclei at 60 degrees C for 15 min. Nuclei which were incubated with GSH also catalyzed the conversion of cumene hydroperoxide to cumyl alcohol. Similarly, this activity was also inhibited by thiol modifying reagents, disulfides, and heating nuclei at 60 degrees C for 15 min. The data suggest that a GSH-dependent peroxidase activity is associated with rat liver nuclear membranes which are capable of inhibiting lipid peroxidation.
Tirmenstein
M A
MA
Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331.
Reed
D J
DJ
D000818:Animals; D001555:Benzene Derivatives / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005978:Glutathione / Q000494:pharmacology*; D007700:Kinetics; D008054:Lipid Peroxides / Q000096:biosynthesis*; D008099:Liver / Q000378:metabolism*; D008297:Male; D009249:NADP / Q000378:metabolism; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains
D001555:Benzene Derivatives; D005231:Fatty Acids, Unsaturated; D008054:Lipid Peroxides; D009249:NADP; D005978:Glutathione; C007164:cumene hydroperoxide