An antioxidant in all tissues and is crucial for many aspects of cell metabolism and survival.
A cysteine-containing peptide found in most forms of aerobic life.
It is not required in the diet and is instead synthesized in cells from its constituent amino acids.
Tissue depletion increases susceptibility to injury.
Uptake of cysteine by cells is a rate limiting step for its synthesis.
Acetylcysteine increases the production of glutathione because it crosses cell membranes readily and can be converted to cysteine.
Glutathione has antioxidant properties since the thiol group in its cysteine moiety is a reducing agent and can be reversibly oxidized and reduced.
In cells, glutathione is maintained in the reduced form by the enzyme glutathione reductase.
It reduces other metabolites and enzyme systems, such as ascorbate in the glutathione-ascorbate cycle, glutathione peroxidases and glutaredoxins, as well as reacting directly with oxidants.