Everything below concerns LC-MS/MS. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-07-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
In its reduced form, glutathione carries a sulfhydryl group that can donate electrons. This property lets it act as a major cellular antioxidant and redox buffer. Glutathione peroxidase uses it to reduce hydrogen peroxide and lipid peroxides, while glutathione reductase regenerates the reduced form using NADPH. The ratio of reduced glutathione to glutathione disulfide is widely used as an indicator of oxidative stress, though the ratio changes with compartment, cell type, and sample handling. Oxidized glutathione can also form mixed disulfides with proteins, affecting their activity.
Glutathione supports detoxification by conjugating reactive electrophiles through glutathione S-transferases. The resulting conjugates are processed and exported, often after further metabolism. It also stores cysteine, transports amino acids across membranes through the gamma-glutamyl cycle, and assists in the maturation of iron-sulfur clusters and some prostaglandins. In plants, animals, and many microbes, the molecule appears in similar roles, but concentrations vary enormously between tissues. Liver, kidney, and red blood cells tend to contain high amounts, while blood plasma contains much less.
Glutathione is a small tripeptide built from glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine uses the gamma-carboxyl group, a linkage that resists ordinary peptidases. Cells make it in two ATP-dependent steps: gamma-glutamylcysteine synthetase joins glutamate and cysteine, then glutathione synthetase adds glycine. The pathway is feedback-inhibited by glutathione itself, so intracellular levels tend to stay within a narrow range. Because cysteine is often limiting, sulfur amino acid supply influences how much glutathione a cell can produce.
Glutathione serves as a cofactor for several enzymes, including glutathione peroxidase and glutathione S-transferase. These enzymes help reduce hydrogen peroxide and lipid peroxides, and they conjugate reactive electrophiles for excretion. The molecule also acts as a reservoir for cysteine, an amino acid that is prone to oxidation. In addition, glutathione participates in the metabolism of nitric oxide, leukotrienes, and prostaglandins. Its roles extend to cell signaling, apoptosis, and the regulation of protein function through S-glutathionylation.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine, and it is the most abundant non-protein thiol in most living cells. The reduced form, GSH, carries a sulfhydryl group that can donate electrons, while the oxidized form, GSSG, forms when two GSH molecules link via a disulfide bond. The balance between these two forms helps define the cellular redox environment, and their ratio is often used as an indicator of oxidative stress. Because the sulfhydryl group is reactive, glutathione participates in many cellular processes, including detoxification and protein regulation.
| Property | Value | Notes |
|---|---|---|
| Chemical formula | C10H17N3O6S | Refers to the reduced form |
| Molar mass | 307.32 g/mol | Calculated for the neutral molecule |
| Appearance | White crystalline powder | Often hygroscopic; protect from moisture |
| Water solubility | Soluble in water | Reported values vary with purity and form |
| Alternative names | GSH, reduced glutathione | GSH specifies the thiol form |
In cells, glutathione exists mainly in a reduced form called GSH. When two GSH molecules react, they form oxidized glutathione, or GSSG, which contains a disulfide bond. The ratio of GSH to GSSG is often used as an indicator of oxidative stress. Enzymes such as glutathione peroxidase and glutathione reductase help cycle the molecule between these two states. This cycling supports antioxidant defense, detoxification of reactive molecules, and regulation of certain signaling pathways.
Glutathione is present in most tissues, with especially high concentrations in the liver. It also serves as a cofactor for some enzymes and helps transport amino acids across cell membranes. In plants and microorganisms, glutathione contributes to stress responses and metal handling. The molecule is synthesized in two ATP-dependent steps, first producing gamma-glutamylcysteine and then adding glycine. Because cysteine availability often limits synthesis, dietary and metabolic factors can influence glutathione levels. Research continues to examine how these levels relate to health and disease.
Measuring glutathione in biological samples requires attention to oxidation, because GSH can convert to GSSG after sample collection. Blood and plasma samples are often treated with acid or alkylating agents to preserve the reduced form. Without stabilization, apparent GSH concentrations can fall while GSSG rises. Differences in sample type, handling delay, and deproteinization method can produce results that are not comparable across studies. Reporting preanalytical details is therefore important for interpreting findings.
Common analytical approaches include enzymatic recycling assays, high-performance liquid chromatography, and mass spectrometry. Enzymatic recycling measures total glutathione after converting GSSG back to GSH, while separation methods can quantify GSH and GSSG separately. Derivatization may be used to improve detection or stability during analysis. LC-MS/MS offers high specificity and can distinguish glutathione from related thiols and adducts. Each method has different sensitivity, throughput, and susceptibility to interference, so method selection depends on the study question and sample matrix.
Glutathione is a small tripeptide built from glutamic acid, cysteine, and glycine. Its peptide bond between glutamate and cysteine involves the gamma-carboxyl group rather than the usual alpha-carboxyl group. This structure gives the molecule a reactive thiol on the cysteine residue. The reduced form, often abbreviated GSH, is the predominant intracellular species in many cell types. Because the thiol can donate electrons, glutathione participates in redox chemistry and in the conjugation of reactive molecules.
Cells synthesize glutathione through two ATP-dependent steps: glutamate-cysteine ligase joins glutamate and cysteine, and glutathione synthetase adds glycine to form the complete tripeptide. Breakdown occurs through gamma-glutamyl transpeptidase and subsequent peptidase reactions, forming the gamma-glutamyl cycle. Within cells, glutathione also forms a disulfide-linked dimer called GSSG when two GSH molecules react. The balance between GSH and GSSG is widely used as an indicator of oxidative conditions, although the ratio can vary by compartment and tissue.
Glutathione supports several cellular processes beyond direct antioxidant action. It serves as a cofactor for glutathione peroxidase and glutathione S-transferase enzymes, which reduce peroxides and conjugate electrophiles, respectively. The molecule also acts as a reservoir of cysteine, an amino acid that can limit protein synthesis and redox signaling. In human nutrition, oral glutathione is sold as a supplement, but how much intact glutathione reaches tissues after ingestion remains an active research question. Clinical claims about supplementation are not uniformly supported by controlled trials.
Enzymatic recycling assays provide a complementary approach for total glutathione. In these methods, glutathione reductase reduces oxidized glutathione while a thiol-reactive reagent, such as 5,5'-dithiobis(2-nitrobenzoic acid), produces a colored product. The reaction cycles between reduced and oxidized forms, amplifying the signal. Spectrophotometric or fluorometric detection can then estimate concentration. Distinguishing reduced glutathione from glutathione disulfide often requires separate aliquots, masking agents, or chromatographic separation, and the choice affects reported values.
Storage conditions strongly influence glutathione stability. The solid reduced form is commonly kept desiccated at or below minus twenty degrees Celsius, protected from light and moisture. Aqueous solutions are less stable because the thiol group reacts with dissolved oxygen, and oxidation accelerates at neutral or alkaline pH. Acidic solutions and oxygen-free handling can slow degradation, but repeated freeze-thaw cycles should be avoided. Researchers often verify concentration before use, because apparent losses can arise from oxidation or water uptake.
== Research == As of October 2025, seltorexant is in phase 3 clinical trials for treatment of major depressive disorder (MDD) and phase 2 trials for treatment of insomnia and Alzheimer's disease. It was also under investigation for the treatment of sleep apnea, but no recent development has been reported for this indication. Seltorexant is under development by Minerva Neurosciences and Johnson & Johnson's Janssen Pharmaceuticals. Seltorexant is being explored at doses of 5 to 80 mg. In the early clinical trials conducted so far, seltorexant has been found to improve depression scores on the Hamilton Depression Rating Scale in people with MDD and to improve sleep onset, total sleep time, time awake after sleep onset, and sleep efficiency in people with MDD and/or insomnia.
== Economic effects == Scotland's identity and heritage are deeply intertwined with Scotch whisky, a cornerstone of the country's economy exported to nearly 180 markets. The Scotch Whisky Association estimated that Scotland's whisky industry supported 40,000 jobs and accounted for £4.37 billion in exports in 2017. Of that total, single malt Scotch accounted for £1.17 billion in exports, a 14% increase over 2016. In 2022, its exports were valued at over £6 billion for the first time. The industry's contribution to the economy of the UK was estimated as £5.5 billion in 2018; the industry provided £3.8 billion in direct GVA (gross value added) to Scotland. Whisky tourism has also become significant and accounts for £68.3 million per year. One factor negatively affected sales, an extra 3.9% duty on spirits imposed by the UK in 2017. (The effect of the 25% increase in tariffs imposed by the U.S. in October 2019 would not be apparent until 2020.) Nonetheless, by year-end 2017, exports had reached a record-breaking amount. In November 2019, the Association announced that the government of the UK had agreed to consider revising the alcohol taxation system, hopefully producing a new plan that was simplified and "fairer". Exports in 2018 again increased 7.8% by value, and 3.6% in the number of bottles, in spite of the duty imposed in 2017; exports grew to a record level, £4.7 billion. The US imported Scotch whisky with a value of just over £1 billion while the European Union was the second-largest importer, taking 30% of global value.
The early European studies of what is now known as Lyme disease described its skin manifestations. The first study dates to 1883 in Breslau, Germany (now Wrocław, Poland), where physician Alfred Buchwald described a man who for 16 years had had a degenerative skin disorder now known as acrodermatitis chronica atrophicans. At a 1909 research conference, Swedish dermatologist Arvid Afzelius presented a study about an expanding, ring-like lesion he had observed in an older woman following the bite of a sheep tick. He named the lesion erythema migrans. The skin condition now known as borrelial lymphocytoma was first described in 1911.
Databases are essential for bioinformatics research and applications. Databases exist for many different information types, including DNA and protein sequences, molecular structures, phenotypes and biodiversity. Databases can contain both empirical data (obtained directly from experiments) and predicted data (obtained from analysis of existing data). They may be specific to a particular organism, pathway or molecule of interest. Alternatively, they can incorporate data compiled from multiple other databases. Databases can have different formats, access mechanisms, and be public or private. Some of the most commonly used databases are listed below: Used in biological sequence analysis: Genbank, UniProt Used in structure analysis: Protein Data Bank (PDB) Used in finding Protein Families and Motif Finding: InterPro, Pfam Used for Next Generation Sequencing: Sequence Read Archive Used in Network Analysis: Metabolic Pathway Databases (KEGG, BioCyc), Interaction Analysis Databases, Functional Networks Used in design of synthetic genetic circuits: GenoCAD
2023 Analytical Scientist the Power List - Leaders and Advocates 2020 Society for Glycobiology Molecular and Cellular Proteomics (MCP) / American Society for Biochemistry and Molecular Biology (ASBMB) Lectureship Award 2019 inaugural winner of the US Human Proteome Organization Lifetime Achievement in Proteomics Award 2019 Analytical Scientist the Power List 2017 American Society for Mass Spectrometry John B. Fenn Award for a Distinguished Contribution in Mass Spectrometry 2016 American Association for the Advancement of Science Fellow 2015 Human Proteome Organization Distinguished Service Award 2015 German Mass Spectrometry Society (Deutsche Gesellschaft für Massenspektrometrie, DGMS) Wolfgang Paul Lecture 2013 Boston University The William Fairfield Warren Distinguished Professorship 2011 American Chemical Society Fellow 2010 American Chemical Society Frank H. Field and Joe L. Franklin Award for Outstanding Achievement in Mass Spectrometry 2009 International Mass Spectrometry Foundation Thomson Medal 2008 Human Proteome Organization Discovery in Proteomic Sciences Award
Sources: en.wikipedia.org
=== Russia === Russia has a plan for increasing its fleet of fast breeder reactors significantly. A BN-800 reactor (800 MWe) at Beloyarsk was completed in 2012, succeeding a smaller BN-600. It reached its full power production in 2016. Plans for the construction of a larger BN-1200 reactor (1,200 MWe) was scheduled for completion in 2018, with two additional BN-1200 reactors built by the end of 2030. However, in 2015 Rosenergoatom postponed construction indefinitely to allow fuel design to be improved after more experience of operating the BN-800 reactor, and among cost concerns. In January 2026, Rosatom reported that preparations had begun for Beloyarsk Unit 5, using the BN-1200M sodium-cooled fast reactor. Construction of the lead-cooled BREST-OD-300 reactor at the Siberian Chemical Combine in Seversk began in June 2021. The BREST (Russian: bystry reaktor so svintsovym teplonositelem, English: fast reactor with lead coolant) design is seen as a successor to the BN series and the 300 MWe unit at the SCC could be the forerunner to a 1,200 MWe version for wide deployment as a commercial power generation unit. The development program is as part of an Advanced Nuclear Technologies Federal Program 2010–2020 that seeks to exploit fast reactors for uranium efficiency while 'burning' radioactive substances that would otherwise be disposed of as waste. Its core would measure about 2.3 metres in diameter by 1.1 metres in height and contain 16 tonnes of fuel. The unit would be refuelled every year, with each fuel element spending five years in total within the core.
== History == AZD-2327 was first described by 2004 and was first described in the scientific literature in 2009. The development of AZD-2327 was discontinued in 2010. It reached phase 2 clinical trials for both depressive disorders and anxiety disorders prior to its discontinuation. No reason was given for the discontinuation of its development. However, the drug was found to be ineffective for major depressive disorder in a phase 2 clinical trial. AZD-2327 was developed by AstraZeneca.
The Greenspan lab was also involved in studies showing that mutations that affect the protease BMP-1 underlie some cases of osteogenesis imperfecta (brittle bone disease), and showing molecular mechanisms involved.
Ginkgo biloba, commonly known as ginkgo ( GINK-oh, -goh), also known as the maidenhair tree, and often misspelled "gingko" (see Taxonomy below) is a species of gymnosperm tree native to East Asia. It is the last living species in the order Ginkgoales, which first appeared over 290 million years ago. Fossils similar to the living species, belonging to the genus Ginkgo, extend back to the Middle Jurassic epoch about 170 million years ago. The tree was cultivated early in human history, remains commonly planted, and is widely regarded as a living fossil. G. biloba is a long-lived, disease-resistant, dioecious tree with unique fan-shaped leaves, capable of clonal reproduction, and known for its striking yellow autumn foliage and resilience in disturbed environments. It was known historically as "silver fruit" or "white fruit" in Chinese and called "ginkgo" due to a centuries-old transcription error. It is closely related to cycads and characterized by unique seeds that resemble apricots but are not true fruits. G. biloba, once widespread but thought extinct in the wild for centuries, is now commonly cultivated in East Asia, with some genetically diverse populations possibly representing rare wild survivors in southwestern China's mountainous regions. Some G. biloba trees have survived extreme events like the Hiroshima atomic bomb. Others show extreme longevity; G. biloba specimens have been measured in excess of 1,600 years, and the largest living trees are estimated to exceed 3,500 years.
Sources: en.wikipedia.org
It is a tripeptide of glutamate, cysteine, and glycine. The glutamate-cysteine bond is unusual because it forms through the gamma-carboxyl group.
It reflects the balance between oxidant exposure and antioxidant capacity. The ratio is not a direct clinical diagnosis and depends on the tissue and sample method.
No. It also participates in detoxification, amino acid transport, and protein modification. Its roles vary by cell type and compartment.
Glutathione is a tripeptide of three amino acids: glutamate, cysteine, and glycine. The cysteine residue provides the sulfhydryl group that gives the molecule its reducing properties.