Glutathione peroxidase, Thioredoxin reductase, and Selenoprotein P (GPx, TrxR, SELENOP)

This entry encompasses three major members of the human selenoproteome: Glutathione peroxidase (GPx), Thioredoxin reductase (TrxR), and Selenoprotein P (SELENOP). These proteins are characterized by the presence of selenocysteine in their active sites, which confers high catalytic efficiency in redox reactions (UniProt P07203). Glutathione peroxidases function primarily to reduce hydrogen peroxide and organic hydroperoxides, protecting cells from oxidative stress-induced damage (PubMed: 29129946). Thioredoxin reductases maintain the pool of reduced thioredoxin, which is essential for DNA synthesis via ribonucleotide reductase and for regulating various redox-sensitive transcription factors (UniProt Q16881). Selenoprotein P acts as the primary vehicle for selenium transport from the liver to peripheral tissues and provides extracellular antioxidant defense (UniProt P49908). In oncology, TrxR is often upregulated to support rapid proliferation, making it a target for inhibitors like auranofin (PubMed: 30114478). Conversely, GPx mimics like ebselen are investigated for their ability to mitigate oxidative damage in inflammatory and neurodegenerative conditions (PubChem CID 3194). The collective activity of these proteins is a critical determinant of a cell's ability to survive under conditions of high reactive oxygen species (ROS) production.

Other names

SelenoproteinsSelenium-dependent redox enzymesRedox-regulating selenoproteins

Inhibition of thioredoxin reductase to induce oxidative stress and apoptosis in cancer cells; mimicry of glutathione peroxidase activity to neutralize reactive oxygen species; and supplementation of selenium to facilitate the biosynthesis of functional selenoproteins.