FIG. 5.

Thiols are important antioxidants, and the GSH/GSSG ratio modulates vital cellular processes, including antioxidant systems, apoptosis, cellular growth, and signal transduction among others. Thiols are involved in the extracellular and intracellular oxidative defense, including the mitochondrial and nuclear compartments (To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars.) GSH, glutathione; GSSG, disulfide glutathione; TRX, thioredoxin.