(2S)-2-Amino-5-[[(2R)-3-[(2R)-2-[[(4S)-4-amino-5-hydroxy-5-oxopentanoyl]amino]-3-(carboxymethylamino)-3-oxopropyl]disulfanyl-1- (carboxymethylamino)-1-oxopropan-2-yl]amino]-5-oxopentanoic acid
3D model (Jmol)
|Molar mass||612.63 g·mol−1|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
In living cells, glutathione disulfide is reduced into two molecules of glutathione with reducing equivalents from the coenzyme NADPH. This reaction is catalyzed by the enzyme glutathione reductase. Antioxidant enzymes, such as glutathione peroxidases and peroxiredoxins, generate glutathione disulfide during the reduction of peroxides such as hydrogen peroxide (H2O2) and organic hydroperoxides (ROOH):
- 2 GSH + ROOH → GSSG + ROH + H2O
Other enzymes, such as glutaredoxins, generate glutathione disulfide through thiol-disulfide exchange with protein disulfide bonds or other low molecular mass compounds, such as coenzyme A disulfide or dehydroascorbic acid.
- 2 GSH + R-S-S-R → GSSG + 2 RSH
The GSH:GSSG ratio is therefore an important bioindicator of cellular health, with a higher ratio signifying less oxidative stress in the organism. A lower ratio may even be indicative of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease.
GSSG, along with glutathione and S-nitrosoglutathione (GSNO), have been found to bind to the glutamate recognition site of the NMDA and AMPA receptors (via their γ-glutamyl moieties), and may be endogenous neuromodulators. At millimolar concentrations, they may also modulate the redox state of the NMDA receptor complex.
- Meister A, Anderson ME (1983). "Glutathione". Annual Review of Biochemistry. 52: 711–60. doi:10.1146/annurev.bi.52.070183.003431. PMID 6137189.
- Deneke SM, Fanburg BL (1989). "Regulation of cellular glutathione". The American Journal of Physiology. 257 (4 Pt 1): L163–73. PMID 2572174.
- Meister A (1988). "Glutathione metabolism and its selective modification". The Journal of Biological Chemistry. 263 (33): 17205–8. PMID 3053703.
- Holmgren A, Johansson C, Berndt C, Lönn ME, Hudemann C, Lillig CH (December 2005). "Thiol redox control via thioredoxin and glutaredoxin systems". Biochem. Soc. Trans. 33 (Pt 6): 1375–7. doi:10.1042/BST20051375. PMID 16246122.
- Owen, Joshua B.; Butterfield, D. Allan (2010). "Measurement of oxidized/reduced glutathione ratio". In Bross, Peter; Gregersen, Niels. Protein Misfolding and Cellular Stress in Disease and Aging. Methods in Molecular Biology. 648. pp. 269–77. doi:10.1007/978-1-60761-756-3_18. ISBN 978-1-60761-755-6. PMID 20700719.
- Steullet P, Neijt HC, Cuénod M, Do KQ (2006). "Synaptic plasticity impairment and hypofunction of NMDA receptors induced by glutathione deficit: relevance to schizophrenia". Neuroscience. 137 (3): 807–19. doi:10.1016/j.neuroscience.2005.10.014. PMID 16330153.
- Varga V, Jenei Z, Janáky R, Saransaari P, Oja SS (1997). "Glutathione is an endogenous ligand of rat brain N-methyl-D-aspartate (NMDA) and 2-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors". Neurochemical Research. 22 (9): 1165–71. doi:10.1023/A:1027377605054. PMID 9251108.