This is a working overview of thiol, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-11-02. Anything still debated is marked as such rather than presented as settled.
Interpreting glutathione measurements requires attention to pre-analytical variables. The GSSG concentration in a sample can rise artificially during storage or processing, making the GSH/GSSG ratio unreliable if not controlled. Reference ranges vary by specimen type, assay, and population, so comparisons across studies are difficult. Plasma glutathione is low and sensitive to hemolysis, while whole blood reflects primarily erythrocyte content. Many studies measure total glutathione rather than the reduced and oxidized forms separately, which limits conclusions about redox status.
Accurate measurement of glutathione begins with careful sample handling. Because GSH oxidizes rapidly to GSSG, samples must be processed quickly or frozen immediately. Acid precipitation with metaphosphoric acid or perchloric acid is common; it lowers pH, precipitates proteins, and helps preserve the reduced form. Chelating agents such as EDTA can limit metal-catalyzed oxidation. For whole blood, hemolysis releases glutathione from erythrocytes, so plasma and serum values differ substantially from whole blood values.
Several analytical methods can quantify glutathione, including high-performance liquid chromatography (HPLC) with UV or fluorescence detection for separating GSH and GSSG. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers higher specificity and sensitivity, often detecting nanomolar concentrations. The enzymatic recycling assay, often called the Tietze method, measures total glutathione by coupling reduction of GSSG to a colorimetric or fluorometric readout. Capillary electrophoresis and electrochemical detection are also used in specialized laboratories. Each method has distinct advantages and limitations regarding throughput, cost, and susceptibility to interference.
Synthesis occurs in two ATP-dependent steps. The enzyme glutamate-cysteine ligase joins glutamate and cysteine to form gamma-glutamylcysteine, and glutathione synthetase adds glycine. The first step is rate-limiting and is influenced by cysteine availability and feedback inhibition by GSH. Breakdown involves gamma-glutamyl transferase and subsequent peptidases, which release constituent amino acids for reuse. Because turnover differs among tissues, measurements from blood, plasma, and tissues are not directly interchangeable. Research continues to clarify how compartment-specific pools are regulated in health and disease.
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.
| Property | Value | Notes |
|---|---|---|
| Common analytical method | LC-MS/MS or HPLC | Separation of GSH and GSSG |
| Limit of detection | Nanomolar range | Method dependent |
| Typical sample storage | -80 °C | For biological matrices |
| Common reducing agent | TCEP or DTT | Prevents oxidation during processing |
| Common synonym | Gamma-glutamylcysteinylglycine | Systematic name |
Synthesis occurs in two ATP-dependent steps: glutamate-cysteine ligase joins glutamate and cysteine to form gamma-glutamylcysteine, and glutathione synthetase adds glycine to complete the tripeptide. The pathway is feedback-inhibited by GSH and limited by cysteine availability, so cysteine supply often constrains production. Once formed, GSH participates in redox buffering, xenobiotic conjugation, and protein glutathionylation. Glutathione peroxidase uses GSH to reduce hydrogen peroxide and lipid peroxides, yielding GSSG, while glutathione reductase regenerates GSH using NADPH. Glutathione S-transferases conjugate electrophiles to GSH, supporting detoxification and excretion.
Because GSH is central to redox balance, its status is studied in aging, liver disease, neurodegenerative conditions, and metabolic disorders. Observational studies often report lower GSH or higher GSSG in affected tissues, but such associations do not establish that raising glutathione changes disease outcomes. Oral glutathione is digested into amino acids, and whether intact absorption occurs remains debated; precursors such as N-acetylcysteine and cysteine donors are also investigated. Regulatory agencies generally treat glutathione as a dietary supplement, not an approved drug, and clinical claims require evidence from controlled trials.
Glutathione is a small tripeptide composed of glutamate, cysteine, and glycine, with the unusual gamma-glutamyl linkage between glutamate and cysteine. Its cysteine thiol group makes it a major non-enzymatic antioxidant in cells. The reduced form, GSH, predominates in most intracellular compartments, while the oxidized disulfide form, GSSG, is produced when GSH reduces reactive oxygen species. Intracellular concentrations often reach millimolar levels, whereas plasma concentrations are much lower, typically in the low micromolar range. This gradient reflects active synthesis, transport, and consumption rather than passive distribution.
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.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine uses the gamma-carboxyl group of glutamate rather than the alpha-carboxyl group. This unusual linkage protects the molecule from many common peptidases. The cysteine side chain carries a thiol group that can undergo reversible oxidation. Because of this thiol, glutathione participates in redox reactions and helps maintain the reducing environment inside most cells in living systems.
Mass spectrometry is used where very high sensitivity is required and is sometimes used as a back-end process after gas liquid chromatography for detecting trace organic chemicals. Depending on the components, different methods are applied to determine the quantities or ratios of the components. While some methods can be performed with standard laboratory equipment, others require advanced devices, such as inductively coupled plasma mass spectrometry (ICP-MS).
=== Special cases === Idiopathic infantile hypercalcemia is caused by a mutation of the CYP24A1 gene, leading to a reduction in the degradation of vitamin D. Infants who have such a mutation have an increased sensitivity to vitamin D and in case of additional intake a risk of hypercalcaemia. The disorder can continue into adulthood.
== Medical uses == The primary application for phentolamine is for the control of hypertensive emergencies, most notably due to pheochromocytoma. It also has usefulness in the treatment of cocaine-induced cardiovascular complications, where one would generally avoid β-blockers (e.g., metoprolol), as they can cause unopposed α-adrenergic mediated coronary vasoconstriction, worsening myocardial ischemia and hypertension. Phentolamine is not a first-line agent for this indication. Phentolamine should only be given to patients who do not fully respond to benzodiazepines, nitroglycerin, and calcium channel blockers. When given by injection, it causes blood vessels to dilate, thereby increasing blood flow. When injected into the penis (intracavernosal), it increases blood flow to the penis, which results in an erection. It may be stored in crash carts to counteract severe peripheral vasoconstriction secondary to extravasation of peripherally placed vasopressor infusions, typically of norepinephrine. Epinephrine infusions are less vasoconstrictive than norepinephrine as they primarily stimulate β receptor more than α receptors, but the effect remains dose-dependent. Phentolamine also has diagnostic and therapeutic roles in complex regional pain syndrome (CRPS). Phentolamine is marketed in the dental field as a local anesthetic reversal agent. Branded as OraVerse, it is a phentolamine mesylate injection designed to reverse the local vasoconstrictor properties used in many local anesthetics to prolong anesthesia.
Bronchiolitis obliterans (BO), also known as obliterative bronchiolitis, constrictive bronchiolitis and popcorn lung, is a disease that results in obstruction of the smallest airways of the lungs (bronchioles) due to inflammation. Symptoms include a dry cough, shortness of breath, wheezing and feeling tired. These symptoms generally get worse over weeks to months. It is not related to cryptogenic organizing pneumonia, previously known as bronchiolitis obliterans organizing pneumonia. Causes include breathing in toxic fumes, respiratory infections, connective tissue disorder or complications following a bone marrow or heart-lung transplant. Symptoms may not occur until two to eight weeks following toxic exposure or infection. The underlying mechanism involves inflammation that results in scar tissue formation. Diagnosis is by CT scan, pulmonary function tests or lung biopsy. A chest X-ray is often normal. While the disease is not reversible, treatments can slow further worsening. This may include the use of corticosteroids or immunosuppressive medication. A lung transplant may be offered. Outcomes are often poor, with most people dying in months to years. Bronchiolitis obliterans is rare in the general population. It, however, affects about 75% of people by ten years following a lung transplant and up to 10% of people who have received a bone marrow transplant from someone else. The condition was first clearly described in 1981. Prior descriptions occurred as early as 1956, with the term "bronchiolitis obliterans" used first by Reynaud in 1835.
== See also == Bioluminescence imaging Gene expression Gene knock-in Gene regulatory network GUS reporter system Molecular cloning Promoter (genetics) Selectable marker Synthetic biology Transcription factor Transfection
Sources: en.wikipedia.org
Stress granule assembly is dependent upon the conditions of the cell. In yeast, stress granules form under conditions of high heat. Stress granules are of significance for their roles in mRNA localization, cell signaling pathways, and antiviral processes. Once disassembled, the RNA inside stress granules can go back to translation or be removed as cellular waste. Stress granules may provide protection for mRNA from interactions with the cytosol. Moreover, mutations that affect the formation or degradation of stress granules may contribute to neurodegenerative conditions such as ALS and FTLD. However, the effects of stress granules on cell physiology are still under study.
The Conservative Party under the leadership of Margaret Thatcher won the 1979 general election, placing the Labour Party back in opposition, which served to push the Liberals back into the margins. In 1981, defectors from a moderate faction of the Labour Party, led by former Cabinet ministers Roy Jenkins, David Owen, Shirley Williams and Bill Rodgers founded the Social Democratic Party (SDP). The new party and the Liberals quickly formed the SDP–Liberal Alliance, which for a while polled as high as 50% in the opinion polls and appeared capable of winning the next general election. Indeed, Steel was so confident of an Alliance victory that he told the 1981 Liberal conference, "Go back to your constituencies, and prepare for government!". However, the Alliance was overtaken in the polls by the Tories in the aftermath of the Falkland Islands War and at the 1983 general election the Conservatives were re-elected by a landslide, with Labour once again forming the opposition. While the SDP–Liberal Alliance came close to Labour in terms of votes (a share of more than 25%), it only had 23 MPs compared to Labour's 209. The Alliance's support was spread out across the country, and was not concentrated in enough areas to translate into seats. In the 1987 general election, the Alliance's share of the votes fell slightly and it now had 22 MPs. In the election's aftermath Steel proposed a merger of the two parties. Most SDP members voted in favour of the merger, but SDP leader David Owen objected and continued to lead a "rump" SDP.
=== Reference material === Graphene's properties suggest it as a reference material for characterizing electroconductive and transparent materials. One layer of graphene absorbs 2.3% of red light. This property was used to define the conductivity of transparency that combines sheet resistance and transparency. This parameter was used to compare materials without the use of two independent parameters.
Myomesin plays an important role in the structure of sarcomeres. They are found in the M-band region of the sarcomere, between the thick filaments (myosin). Its main purpose in this setting is to provide structural integrity by linking the antiparallel myosin fibers and titin filaments which are connected to the Z-discs. These myosin filaments form a hexagonal lattice with titin and myomesin. This shape allows the M-band to withstand large conformational changes during muscle contraction and return to their original shape upon relaxation. Since the Z-disc region of the sarcomere is very stiff and unable to bend for contraction, the elastic activity of myomesin in the M-band is what makes muscle contraction possible as it acts as a molecular spring.
Sources: en.wikipedia.org
=== Rash === The superficial burrows of scabies usually occur in the area of the finger webs, feet, ventral wrists, elbows, back, buttocks, and external genitals. Except in infants and the immunosuppressed, infection generally does not occur in the skin of the face or scalp. The burrows are created by the excavation of the adult mite in the epidermis. Acropustulosis, or blisters and pustules on the palms and soles of the feet, are characteristic symptoms of scabies in infants.
Methylhexanamine, also known as 1,3-dimethylamylamine (1,3-DMAA), is an alkylamine. It is closely structurally related to other alkylamines, including 1,3-dimethylbutylamine (1,3-DMBA), 1,4-dimethylamylamine (1,4-DMAA), heptaminol (2-methyl-6-amino-2-heptanol), iproheptine (N-isopropyl-1,5-dimethylhexylamine), isometheptene (2-methyl-6-methylamino-2-heptene), octodrine (2-amino-6-methylheptane or 1,5-dimethylhexylamine), and tuaminoheptane (tuamine; 2-aminoheptane or 1-methylhexylamine). Methylhexanamine and other related alkylamines are similar in chemical structure to phenethylamines and amphetamines, but lack a closed ring. The predicted log P (XLogP3) of methylhexanamine is 1.9.
However, he can't open the hatch by himself. The player must fight through the asylum and the local theater, which is now overrun with zombified soldiers, to meet him on the other side. The player and the deputy take off in a police helicopter. The game reaches its climax as the player and the deputy are forced to fight Dr. Franklin, who, after taking the full impact of the blast in episode 2, has been rebuilt into a half-zombie, half-machine cyborg. After the doctor's defeat, the player is pursued by Sheriff Rockwood in another helicopter with a mounted mini-gun. The player must defeat the sheriff and send him plummeting toward one of the great lakes before exploding. The game ends with the player and the deputy flying off into the sunrise while the game plays "You Are What I Eat" along with the end credits.
Ciglitazone (INN) is a thiazolidinedione. Developed by Takeda Pharmaceuticals in the early 1980s, it is considered the prototypical compound for the thiazolidinedione class. Ciglitazone was never used as a medication, but it sparked interest in the effects of thiazolidinediones. Several analogues were later developed, some of which—such as pioglitazone and troglitazone—made it to the market. Ciglitazone significantly decreases VEGF production by human granulosa cells in an in vitro study, and may potentially be used in ovarian hyperstimulation syndrome. Ciglitazone is a potent and selective PPARγ ligand. It binds to the PPARγ ligand-binding domain with an EC50 of 3.0 μM. Ciglitazone is active in vivo as an anti-hyperglycemic agent in the ob/ob murine model. Inhibits HUVEC differentiation and angiogenesis and also stimulates adipogenesis and decreases osteoblastogenesis in human mesenchymal stem cells.
== Early life and education == King was born in 1934 in an army family. Since childhood, King enjoyed hiking and camping. He graduated from Episcopal High School in Alexandria, Virginia. He received a B.E. in chemical engineering from Yale University in 1956. He then entered Massachusetts Institute of Technology, where he received S.M. in chemical engineering in 1958 and Sc.D. in chemical engineering in 1960, under the supervision of J. Edward Vivian.
Sources: en.wikipedia.org
Glutathione oxidizes quickly when cells are disrupted or when samples sit at room temperature. Rapid processing or immediate freezing minimizes the conversion of GSH to GSSG. This step helps ensure that the measured ratio reflects the original biological state.
The Tietze assay is an enzymatic recycling method that measures total glutathione. It uses glutathione reductase to reduce GSSG back to GSH, which then reacts with a chromogen or fluorophore. The reaction cycles repeatedly, amplifying the signal for detection.
Yes, but the choice of blood fraction matters. Plasma or serum contains low glutathione levels and is easily affected by hemolysis. Whole blood mainly reflects the high glutathione content of erythrocytes, so results from different fractions are not directly comparable.
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.