Glutathione disulfide reduction in tumor mitochondria after t-butyl hydroperoxide treatment.
Treatment of isolated mitochondria from rat hepatoma tumor cells (AS-30D) with the oxidant, t-butyl hydroperoxide (tBuOOH, 1 or 5 mumol/ml) resulted in the oxidation of glutathione (GSH to GSSG) and the formation of protein-glutathione mixed disulfides (ProSSG). The GSSG was retained inside of the hepatoma mitochondria. In the presence of ADP+succinate (5 or 10 mM), or ketoglutarate (10 mM) or malate (5 mM), the GSSG was reduced to GSH, but the amount of ProSSG stayed constant. With saline or ADP+glutamate (10 mM)/malate (0.1 mm) no reduction of GSSG to GSH occurred. The presence of antimycin (5 micrograms/ml) with ADP+succinate inhibited reduction. At a concentration of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU, 0.5 mM) which inhibited a major portion of the glutathione reductase activity, the reduction of GSSG to replenish GSH was also inhibited. NADPH may play a critical role as well, for the addition of 2.4 mM NADPH to permeabilized hepatoma mitochondria fostered the reduction of GSSG after tBuOOH treatment. Therefore, hepatoma mitochondria possess a glutathione reductase-dependent system to reduce GSSG to GSH. The reaction only occurs with actively respiring mitochondria.
Brodie
A E
AE
Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331-6503.
Reed
D J
DJ
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D000968:Antimycin A / Q000031:analogs & derivatives / Q000494:pharmacology; D002330:Carmustine / Q000494:pharmacology; D005978:Glutathione / Q000031:analogs & derivatives* / Q000378:metabolism; D019803:Glutathione Disulfide; D005980:Glutathione Reductase / Q000378:metabolism; D007656:Ketoglutaric Acids / Q000494:pharmacology; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008293:Malates / Q000494:pharmacology; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D009249:NADP / Q000494:pharmacology; D010084:Oxidation-Reduction; D010545:Peroxides / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013386:Succinates / Q000494:pharmacology; D019802:Succinic Acid; D020122:tert-Butylhydroperoxide
D007656:Ketoglutaric Acids; D008293:Malates; D010545:Peroxides; D013386:Succinates; C032456:antimycin; D009249:NADP; D000244:Adenosine Diphosphate; D000968:Antimycin A; C030298:malic acid; D020122:tert-Butylhydroperoxide; D019802:Succinic Acid; D005980:Glutathione Reductase; D005978:Glutathione; D002330:Carmustine; D019803:Glutathione Disulfide