A practical reference on glutathione: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-07-03 and is reviewed periodically as new material appears.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. It occurs in nearly all living cells, with highest concentrations in liver, kidney, and red blood cells, and exists in reduced (GSH) and oxidized disulfide (GSSG) forms. The cysteine thiol group enables reversible oxidation and reduction reactions. This property makes glutathione a central participant in cellular redox balance. The balance between these forms is often used as an indicator of oxidative stress.
Glutathione synthesis proceeds in two ATP-dependent steps catalyzed by glutamate-cysteine ligase and glutathione synthetase. The first step joins glutamate and cysteine to form gamma-glutamylcysteine and is generally rate-limiting. The second step adds glycine to complete the tripeptide. Cysteine availability, feedback inhibition by glutathione, and oxidative conditions influence flux through this pathway. The pathway is conserved across many organisms, and degradation by gamma-glutamyl transpeptidase and related peptidases recycles amino acids for new synthesis.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. It contains an unusual gamma-glutamyl bond between glutamate and cysteine, which resists cleavage by many peptidases. The reduced form, GSH, carries a thiol group on cysteine and is the dominant intracellular form in most cells. Its structure allows it to participate in redox reactions and to serve as a sulfur donor. The oxidized form, GSSG, consists of two GSH molecules joined by a disulfide bond.
In cells, glutathione helps maintain the reducing environment of the cytosol and supports enzymes that counteract reactive oxygen species. It acts as a cofactor for glutathione peroxidases, which reduce hydrogen peroxide and lipid peroxides, and for glutathione S-transferases, which conjugate electrophiles. The ratio of GSH to GSSG is often used as an indicator of oxidative stress, although the ratio can vary by compartment and cell type. Glutathione also stores cysteine, an amino acid that can be limiting for protein synthesis and antioxidant defense.
| Property | Value | Notes |
|---|---|---|
| Common name | Glutathione | Reduced form is abbreviated GSH |
| Chemical class | Tripeptide | Composed of glutamate, cysteine, and glycine |
| Molar mass | 307.32 g/mol | For reduced glutathione |
| CAS Registry Number | 70-18-8 | For reduced L-glutathione |
| Appearance | White crystalline powder | Typical solid reference material |
Arranging a secret deal in which Tippett would be traded to a club of his choice at the end of 2012 Direct payments of $100,000 outside the salary cap in each of 2011 and 2012 Illegally arranging third-party deals in 2011 and 2012, resulting in Tippett receiving further money outside the salary cap in those years. Adelaide was considered likely to incur a loss of draft picks, among other penalties, if found guilty, but the AFL Commission was yet to complete its hearing into the matter when the National Draft was held on 22 November 2012, so the club was permitted to participate in the draft as normal. However, on the day before the draft, the club voluntarily relinquished its highest two remaining selections (No. 20 and 54) as a "gesture of goodwill" ahead of the hearing. The final hearing took place on 30 November, and Adelaide and Tippett pleaded guilty to all charges. Adelaide was stripped of its first and second round draft picks, and banned from taking any father-son selections, in the 2013 National Draft, and received a $300,000 fine. Tippett was suspended for the 2013 NAB Cup and 11 premiership matches, with a further suspended sentence of 11 matches, and received a $50,000 fine. Several senior Adelaide personnel were also punished by the league: chief executive Steven Trigg and former football manager John Reid were each fined $50,000 and banned from AFL functions for six months (with a further suspended sentence of six months), and current football manager Phil Harper was banned from AFL functions for two months with a four-month suspended sentence.
=== Activity-based protein profiling === Activity-based protein profiling (ABPP, also activity-based proteomics) is a technique that was developed to monitor the availability of enzymatic active sites to their endogenous ligands. ABPP uses specially designed probes that enter and form a covalent bond with an enzyme's active site, which confirms that the enzyme is an active state. The probe is typically an analog of the drug whose mechanism is being studied, so covalent labeling of an enzyme is indicative of drug binding. ABPP probes are designed with three key functional units: (1) a site-directed covalent warhead (reactive group); (2) a reporter tag, such as biotin or rhodamine; and (3) a linker group. The site-directed covalent warhead, also called a covalent modifier, is an electrophile that covalently modifies a serine, cysteine, or lysine residue in the enzyme's active site and prevents future interactions with other ligands. ABPP probes are generally designed against enzymatic classes, and thus can provide systems-level information about the impact of cell state on enzymatic networks. The reporter tag is used to confirm labeling of the enzyme with the reactive group and can vary depending on the downstream readout. The most widely used reporters are fluorescent moieties that enable imaging and affinity tags, such as biotin, that allow for pull-down of labeled enzymes and analysis via mass spectrometry.
Pharmacokinetics (from Ancient Greek pharmakon 'drug' and kinetikos 'moving, putting in motion'; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to describing how the body affects a specific substance after administration. The substances of interest include any chemical xenobiotics such as pharmaceutical drugs, pesticides, food additives, cosmetics, etc. PK attempts to analyze chemical metabolism and discover the fate of a chemical from the moment that it is administered up to the point at which it is completely eliminated from the body. PK is based on mathematical modeling that places great emphasis on the relationship between drug plasma concentration and the time elapsed since the drug's administration. Pharmacokinetics is the study of how an organism affects the drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. Both together influence dosing, benefit, and adverse effects, as seen in PK/PD models.
Sources: en.wikipedia.org
=== Management of acute flare === During moderate or severe symptomatic attacks, a short course (usually 3–5 days) of high doses of corticosteriods is the usual approach. Initially, oral corticosteroids are used; if that is ineffective, an intravenous course can be tried. Milder attacks may not need treatment. Although targeted at acute attacks, they might also have a small longer-term benefit. Severe attacks that do not respond to corticosteroids might be treatable by plasma exchange.
Here, RA is the isotope amount ratio of the natural analyte, RA = n(iA)A/n(jA)A, RB is the isotope amount ratio of the isotopically enriched analyte, RB = n(iA)B/n(jA)B, RAB is the isotope amount ratio of the resulting mixture, x(jA)A is the isotopic abundance of the minor isotope in the natural analyte, and x(jA)B is the isotopic abundance of the major isotope in the isotopically enriched analyte. For elements with only two stable isotopes, such as boron, chlorine, or silver, the above single dilution equation simplifies to the following:
=== Pharmacokinetics === Flurpiridaz (18F) has peak blood radioactivity at 2.3 minutes after administration, followed by a rise and plateau. Distribution of this radiopharmaceutical is complex, as it transfuses into the liver (13%), kidneys (9%), brain (8%) and epicardium (3%, radioactivity retains for 1 hour after administration). Full clearance is achieved within 48 hours. Only metabolites of flurpiridaz are excreted, mainly in urine and feces. Flurpiridaz metabolises into many different polar metabolites. There are no differences in pharmacokinetics caused by age, sex, body mass index (BMI), diabetic status, Clid Pugh A hepatic impairment and renal impairment at eGFR≥19-89 mL/min.
Sources: en.wikipedia.org
GSH is the reduced thiol form, while GSSG is the disulfide-linked oxidized dimer. The GSH:GSSG ratio is used as a redox indicator, though the ratio can vary with sample handling and cell type.
Glutathione is present in many foods, including meats, poultry, fish, some vegetables, and fruits. Cooking, storage, and digestion affect the amounts available for absorption.
Yes, both enzymatic steps in glutathione synthesis consume ATP. The first step, catalyzed by glutamate-cysteine ligase, is usually rate-limiting.
GSH is the reduced form with a free thiol group, while GSSG is the oxidized disulfide-linked dimer. Most assays distinguish the two because their balance reflects redox conditions. The names are not interchangeable.