Thiol is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-05-11. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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.
| 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 |
Glutathione functions in redox balance, detoxification, and sulfur amino acid storage. It participates in reactions that help maintain ascorbate and protein thiol status. The molecule serves as a cofactor for several enzymes, including glutathione peroxidases and glutathione S-transferases. These enzymes reduce peroxides and conjugate electrophiles, respectively. Glutathione also contributes to the metabolism of xenobiotics and to the transport of cysteine between tissues. How interorgan transport and tissue-specific regulation shape whole-body pools remains an active area of study.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. Its cysteine residue carries a thiol group, which allows the molecule to participate in reduction and oxidation reactions. The compound exists in most living cells, where the reduced form, often abbreviated GSH, is usually more abundant than the oxidized disulfide form, GSSG. Intracellular concentrations are commonly in the millimolar range, while extracellular concentrations are much lower. This uneven distribution supports its role as a major cellular redox buffer.
Cells synthesize glutathione through two ATP-dependent enzymatic steps. The first step combines glutamate and cysteine to form gamma-glutamylcysteine, catalyzed by glutamate-cysteine ligase. The second step adds glycine, producing the complete tripeptide, catalyzed by glutathione synthetase. Glutathione itself can inhibit the first enzyme, providing negative feedback when levels are high. Because cysteine is often limiting, its availability influences how quickly the pathway proceeds. These reactions occur in the cytosol, and the resulting glutathione can be distributed to other compartments.
Glutathione participates in detoxification reactions, amino acid transport, and the maintenance of protein thiols. It serves as a cofactor for several enzymes, including glutathione peroxidases and glutathione S-transferases. In research literature, altered glutathione status appears in studies of aging, infection, metabolic stress, and environmental exposure. Whether low glutathione is a cause, consequence, or marker of such conditions often remains unresolved. Direct measurement in blood or tissue provides a snapshot, but results depend on sample handling, timing, and the method used.
Glutathione is a small tripeptide made of glutamic acid, cysteine, and glycine. Its cysteine thiol group allows reversible oxidation and reduction, making it central to cellular redox chemistry. The reduced form, often abbreviated GSH, predominates inside most cells, while the oxidized disulfide form, GSSG, forms when two GSH molecules react. The ratio of GSH to GSSG is widely used as an indicator of oxidative stress in laboratory research, though it does not by itself diagnose a clinical condition.
Bats provide humans with some direct benefits, at the cost of some disadvantages. Bat dung has been mined as guano from caves and used as fertiliser. Bats consume insect pests, reducing the need for pesticides and other insect management measures. Bats are sometimes numerous enough and close enough to human settlements to serve as tourist attractions, and they are used as food in Africa, Asia, the Pacific and the Caribbean. Due to their physiology, bats are one type of animal that acts as a natural reservoir of many pathogens, such as rabies, and since they are highly mobile, social, and long-lived, they can readily spread disease among themselves. If humans interact with bats, these traits become potentially dangerous to humans. Depending on the culture, bats may be symbolically associated with positive traits, such as protection from certain diseases or risks, rebirth, or long life, but in the West, bats are popularly associated with darkness, malevolence, witchcraft, and vampires.
In 2005, the FDA added a boxed warning concerning pediatric suicidal behavior to all antidepressants, including sertraline. In 2007, labeling was again changed to add a warning regarding suicidal behavior in young adults ages 18 to 24.
== Mechanism of action == Nitrovasodilators are prodrugs that donate NO by various mechanisms. Nitrates undergo chemical reduction, likely mediated by enzymes. Molsidomine and nitroprusside already contain nitrogen in the right oxidation state (+2) and liberate NO without the aid of enzymes. NO stimulates the soluble form of the enzyme guanylate cyclase in the smooth muscle cells of blood vessels. Guanylate cyclase produces cyclic guanosine monophosphate (cGMP) from guanosine triphosphate (GTP). cGMP in turn activates cyclic nucleotide-dependent protein kinase G, which phosphorylates various proteins that play a role in decreasing intracellular calcium levels, leading to relaxation of the muscle cells and thus to dilation of blood vessels. The most important effect in angina is the widening of veins, which increases their capacity to hold blood ("venous pooling") and reduces the pressure of the blood returning to the heart (the preload). Widening of the large arteries also reduces the pressure against which the heart has to pump, the afterload. Lower preload and afterload result in the heart needing less energy and thus less oxygen. Besides, NO donated by nitrovasodilators can reduce coronary spasms, increasing the heart's oxygen supply. PDE5 inhibitors block deactivation of cGMP by the enzyme phosphodiesterase-5. In combination with the increased cGMP production caused by nitrovasodilators, this leads to high concentrations of cGMP, extensive venous pooling, and potentially life-threatening hypotension.
A permanent routine of exercise, eating healthily, and, during periods of being overweight, consuming the same number or fewer calories than used will prevent and help fight obesity. A single pound of fat yields approximately 3500 calories of energy (32 000 kJ energy per kilogram of fat), and weight loss is achieved by reducing energy intake, or increasing energy expenditure, thus achieving a negative balance. Adjunctive therapies which may be prescribed by a physician are orlistat or sibutramine, although the latter has been associated with increased cardiovascular events and strokes and has been withdrawn from the market in the US, the UK, the EU, Australia, Canada, Hong Kong, and Thailand. A 2006 study published in the International Journal of Sport Nutrition and Exercise Metabolism suggests that combining cardiovascular (aerobic) exercise with resistance training is more effective than cardiovascular training alone in getting rid of abdominal fat. An additional benefit to exercising is that it reduces stress and insulin levels, which reduce the presence of cortisol, a hormone that leads to more belly fat deposits and leptin resistance. Age-related increases in central adiposity are strongly linked to a progressive decline in basal metabolic rate and loss of lean body mass in adult males. To effectively reduce visceral fat and maintain metabolic health, structured physical activity combining both aerobic and resistance training is recommended.
Sources: en.wikipedia.org
== Further reading. == Mendelsohn, John Andrew. "Cultures of bacteriology: Formation and transformation of a science in France and Germany, 1870-1914" (PhD dissertation, Princeton University' ProQuest Dissertations & Theses, 1996. 9701218).
== Indications (biomarkers) == The most common biomarker for exposure to AzM is the inhibition of AChE. Also other esterase enzymes as CaE and BChE are inhibited by AzM. In general AzM exposure can be better detected by AChE inhibition than CaE inhibition. In amphibians and also zebrafish, AChE is a more sensitive biomarker for low AzM exposure-levels. As already mentioned in paragraph 7 “detoxification”, AzM can be metabolized into nontoxic dimethylated alkylphosphates (AP), with the help of CYP450 and glutathione. These APs are: dimethylphosphate (DM), dimethylthiophosphate (DMTP) and dimethyldithiophosphate (DMDTP). These three metabolites may be excreted into the urine and can be used as reliable biomarkers of exposure to AzM. However these metabolites are not specific to AzM, because other organophosphate pesticides might also be metabolized into the three alkylphosphates. The amount of erythrocyte acetylcholinesterase (RBE-AChE) in the blood can also be used as a biomarker of effect for AzM. According to Zavon (1965) RBC-AChE is the best indicator of AChE activity at the nerve synapse, because this closely parallels the level of AChE in the CNS and PNS. A depression of RBC-AChE will correlate with effects due to a rapid depression of AChE enzymes found in other tissues, this is due to the fact that both enzymes can be inhibited by AzM.
Alongside the general election, voters were asked to participate in a referendum regarding a proposed rewrite of the country's 2017 Constitution. On election night, unofficial results reported by Al Jazeera indicated that more than 57 per cent of voters had supported the drafting of a new constitution. People's Party leader Natthaphong Ruengpanyawut acknowledged that the referendum appeared to have been approved and stated his party would respect the parliamentary process. The proposal was carried. According to the Election Commission, 21,621,638 voters (60.16 per cent) approved the drafting of a new constitution, 11,241,653 (31.28 per cent) rejected it and 3,074,330 (8.55 per cent) expressed no opinion, from 35,937,621 valid ballots. A further 932,583 ballots were rejected as invalid. Turnout in the referendum was 36,870,266, or 69.65 per cent, about 937,000 fewer ballots than were cast in the general election held the same day. Support was broadly spread, with 288 of the 400 constituencies recording a 'yes' vote above 70 per cent and only 38 recording a 'no' vote above 50 per cent, two of them in Buriram and the remaining 36 in the upper south.
The beta decay of Pu-241 forms Am-241; the in-growth of americium is likely to be a greater problem than the decay of Pu-239 and Pu-240 as the americium is a gamma emitter (increasing external-exposure to workers) and is an alpha emitter which can cause the generation of heat. The plutonium could be separated from the americium by several different processes; these would include pyrochemical processes and aqueous/organic solvent extraction. A truncated PUREX type extraction process would be one possible method of making the separation. Naturally occurring uranium is not fissile because it contains 99.3% of U-238 and only 0.7% of U-235.
During the events of the crossover film Tokusou Sentai Dekaranger vs. Abaranger, Trinoid #0 Saunaginnan resurrects Ben G, who is subsequently killed by Deka Master, Pink, and Break, as well as Abare Killer. Ben G is voiced by Nobuyuki Hiyama (檜山 修之, Hiyama Nobuyuki). Cristonian Ferley (クリスト星人ファーリー, Kurisuto Seijin Fārī): A werewolf/vampire bat–themed criminal from Planet Cristo who is charged with burglary and murdering several S.P.D. officers. As his body is photosensitive, he tasks a Batsuroid with piloting a Kaijuki called Devil Capture 4 (デビルキャプチャー4, Debiru Kyapuchā Fō) to distract the Dekarangers while Ferley locates and eats a mineral called Lunar Metal so he can roam freely in daylight. Devil Capture 4 is destroyed by Dekaranger Robo while Ferley is deleted by the Dekarangers via the D-Bazooka. In the direct-to-video special Tokusou Sentai Dekaranger Super Video: Super Finisher Match! Deka Red vs. Deka Break, a variation of Ferley called Burning Ferley (バーニング・ファーリー, Bāningu Fārī) appears as part of a simulation training session. Ferley is voiced by Hisao Egawa (江川 央生, Egawa Hisao). Titarnian Metiussl (ティタン星人メテウス, Titan Seijin Meteusu): A brutal flame/astronaut–themed criminal and self-proclaimed "Destroyer King" (破壊王, Hakaiō) from Planet Titarn who seeks out an android girl named Flora, whom he created to control his giant creation Machine Monster Gigas (マシンモンスター・ギーガス, Mashin Monsutā Gīgasu). He tasks a Batsuroid with piloting a gladiator-themed Kaijuki called Cannon Gladiator (キャノングラディエーター, Kyanon Guradiētā) and attacking the Deka Base while he locates Flora.
Sources: en.wikipedia.org
== Corporate structure == TikTok Ltd was incorporated in the Cayman Islands in the Caribbean and is based in both Singapore and Los Angeles. It owns entities which are based respectively in Australia (which also runs the New Zealand business), United Kingdom (also owns subsidiaries in the European Union), and Singapore (owns operations in Southeast Asia and India). A spin-off company, TikTok USDS Joint Venture LLC was formed on 22 January 2026 to handle TikTok and other ByteDance properties in the United States. Oracle Corporation, MGX Fund Management Limited, Silver Lake each hold a 15% stake, ByteDance holds a 19.9% stake, and the remaining 35.1% is shared between Dell Technologies founder Michael Dell and Vastmere Strategic Investments. Its parent company, Beijing-based ByteDance, is owned by founders and Chinese investors, other global investors, and employees. One of ByteDance's main domestic subsidiaries is owned by Chinese state funds and entities through a 1% golden share. Employees have reported that multiple overlaps exist between TikTok and ByteDance in terms of personnel management and product development. TikTok says that since 2020, its US-based CEO is responsible for making important decisions, and has downplayed its China connection.
===== Iron export ===== Iron export occurs in a variety of cell types, including neurons, red blood cells, macrophages and enterocytes. The latter two are especially important since systemic iron levels depend upon them. There is only one known iron exporter, ferroportin. It transports ferrous iron out of the cell, generally aided by ceruloplasmin and/or hephaestin (mostly in enterocytes), which oxidize iron to its ferric state so it can bind ferritin in the extracellular medium. Hepcidin causes the internalization of ferroportin, decreasing iron export. Besides, hepcidin seems to downregulate both TFR1 and DMT1 through an unknown mechanism. Another player assisting ferroportin in effecting cellular iron export is GAPDH. A specific post translationally modified isoform of GAPDH is recruited to the surface of iron loaded cells where it recruits apo-transferrin in close proximity to ferroportin so as to rapidly chelate the iron extruded. The expression of hepcidin, which only occurs in certain cell types such as hepatocytes, is tightly controlled at the transcriptional level and it represents the link between cellular and systemic iron homeostasis due to hepcidin's role as "gatekeeper" of iron release from enterocytes into the rest of the body. Erythroblasts produce erythroferrone, a hormone which inhibits hepcidin and so increases the availability of iron needed for hemoglobin synthesis.
=== Ancient Greece and Rome === Lime (calcium oxide) was used on Crete and by the Ancient Greeks. There is evidence that the Minoans of Crete used crushed potsherds as an artificial pozzolan for hydraulic cement. Nobody knows who first discovered that a combination of hydrated non-hydraulic lime and a pozzolan produces a hydraulic mixture (see also: Pozzolanic reaction), but such concrete was used by the Greeks, specifically the Ancient Macedonians, and three centuries later on a large scale by Roman engineers.
== Early life and education == Abdel Fattah al-Burhan was born in 1960 in the village of Gandatu in northern Sudan, to a Ja'ali family. Al-Burhan studied elementary and intermediate level in his village school, and later moved to Shendi to complete his education before joining the Sudanese Military College.
In July 2024, Lyme Disease Vaccine Reached Completion of the Primary Series In July 2024, Pfizer and Flagship Pioneering announced an "Innovation Supply Chain" partnership to co-develop 10 drug candidates. Each party committed $50 million upfront, leveraging Flagship's ecosystem of over 40 startups to align with Pfizer's priorities. Pfizer will fund the selected programs and has the option to license or acquire assets, with potential success milestones and royalties reaching up to $700 million per commercialized drug. Two programs, focused on obesity and cardiovascular diseases, have already been initiated. In July 2024, Pfizer advanced its obesity treatment research through the development of danuglipron, an oral glucagon-like peptide-1 (GLP-1) receptor agonist: In August 2024, Pfizer introduced PfizerForAll, a digital platform designed to streamline access to healthcare and wellness resources in the United States. In October 2024, Pfizer announced positive results from phase 3 TALAPRO-2 trial of Talzenna in combination with Xtandi in patients with mCRPC. In October 2024, Pfizer announced a partnership with the Ignition AI Accelerator, a collaborative initiative by Nvidia, Tribe, and Digital Industry Singapore (DISG). The collaboration aims using artificial intelligence to expedite drug discovery and development processes, improve operational efficiency, and streamline stakeholder engagement. The initiative also focuses on optimizing manufacturing processes, including improving yields and reducing cycle times.
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.
It is a tripeptide of glutamic acid, cysteine, and glycine. The linkage between glutamate and cysteine uses the gamma-carboxyl group, which is unusual for peptides.