title: Rat hepatic cytosolic glutathione-dependent enzyme protection against lipid peroxidation in the NADPH-microsomal lipid peroxidation system.
abstract: Dialyzed rat liver cytosol (105 000 X g supernatant), when added along with 2.5 mM glutathione, blocked malonaldehyde formation in the NADPH-microsomal lipid peroxidation system, thus protecting against lipid peroxidation. Preheating the cytosol for 10 min at 60 degrees C destroyed its protective ability. Ammonium sulfate fractionation and Sephadex G-100 gel filtration of cytosol indicated that more than one glutathione-dependent protective enzyme was present. Fractions from the G-100 column containing the selenoenzyme glutathione peroxidase failed to protect, but fractions containing the glutathione S-transferases, which have non selenium-dependent glutathione peroxidase activity, did protect. The glutathione S-transferases were purified further with ion exchange chromatography and shown to have protective activity. Thus the rat hepatic cytosolic glutathione-dependent enzyme protection against lipid peroxidation in the NADPH-microsomal lipid peroxidation system is in part due to some of the glutathione S-transferases. The selenium-dependent glutathione peroxidase appears to have no protective effect in this system.
mesh_terms: D000818:Animals; D003600:Cytosol / Q000378:metabolism; D005978:Glutathione / Q000494:pharmacology*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D066298:In Vitro Techniques; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008862:Microsomes, Liver / Q000378:metabolism; D009249:NADP / Q000378:metabolism*; D051381:Rats; D012643:Selenium / Q000494:pharmacology
chemical_list: D008315:Malondialdehyde; D009249:NADP; D005979:Glutathione Peroxidase; D005982:Glutathione Transferase; D005978:Glutathione; D012643:Selenium