Glutathione reductase
Glutathione reductase is the enzyme that recycles oxidised glutathione (GSSG) back into two molecules of working, reduced glutathione (GSH), using electrons from NADPH.
Also called GR, GSR (its gene).
Recycling is how cells keep glutathione working without making every molecule new, and glutathione reductase is the principal enzyme that regenerates GSH from GSSG (Del Carlo 2003). The NADPH it draws on comes largely from the pentose phosphate pathway, a branch of glucose metabolism.
In human cartilage cells, oxidative stress lowered the activity of glutathione reductase and of thioredoxin reductase, but not of catalase (Del Carlo 2003). Cells from older donors also had a higher ratio of GSSG to GSH, and the authors concluded that a dysregulated glutathione system makes ageing chondrocytes more vulnerable to oxidant-driven cell death (Del Carlo 2003).
Sources
- Carlo MD Jr, Loeser RF. Increased oxidative stress with aging reduces chondrocyte survival: correlation with intracellular glutathione levels. Arthritis Rheum 2003.
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