Oxidative Modification of Enzymes During Aging and Acute Oxidative Stress
Previous studies have demonstrated that many cellular enzymes accumulate as catalytically inactive or less active forms during normal aging.1,2 The mechanism(s) for these changes has (have) not been determined. However, because many of the enzymes which exhibit loss of enzymatic activity during aging are also inactivated by mixed-function oxidation (MFO) systems in vitro,3,4 we have considered the possibility that these changes may be due to oxidative inactivation by MFO systems in vivo. In the studies reported here we have examined the levels of oxidatively modified proteins in hepatocytes isolated from young and old rats and from young rats subjected to treatment with 100% oxygen.
KeywordsGlutamine Synthetase Protein Carbonyl Oxidative Modification Glutamine Synthetase Activity Protein Carbonyl Content
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