Everything below concerns GSSG. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
In living systems, glutathione occurs in millimolar concentrations in many cell types, while extracellular levels are generally much lower. The liver holds a substantial share of the body's total pool, and the molecule participates in reduction, detoxification, and amino acid transport. It also serves as a cofactor for enzymes such as glutathione peroxidase and glutathione S-transferase. Because the cysteine residue supplies a reactive thiol, glutathione can donate electrons and become oxidized. Cells regenerate reduced glutathione through glutathione reductase using NADPH.
Commercial glutathione is produced by microbial fermentation or chemical synthesis, then purified. Reduced and oxidized grades are offered separately, with purity specifications often exceeding 98 percent. The compound appears in foods such as fresh fruits, vegetables, and meats, although cooking and processing can lower amounts. Oral, topical, and inhaled forms are discussed in research and consumer contexts, but absorption and tissue delivery remain active areas of study. Regulatory status varies by country and intended use.
Measuring glutathione requires attention to sample preparation because the molecule oxidizes readily. Blood, tissue, and cell samples are often treated with acid to precipitate proteins and stabilize the thiol. Without such steps, GSH can convert to GSSG or form mixed disulfides during storage. Analytical methods include spectrophotometric assays, high-performance liquid chromatography, and mass spectrometry. Each approach has different sensitivity, specificity, and susceptibility to interference from related compounds in complex matrices.
For solid glutathione, storage conditions affect shelf life. The reduced form is typically kept cool, dry, and protected from air and light. Moisture can promote oxidation, while elevated temperatures accelerate degradation. Suppliers often specify storage at or below freezing, sometimes under inert gas. Solutions are less stable than powders and may require preparation shortly before use. Buffers and chelating agents can slow oxidation, but they do not eliminate it. Published stability data vary with matrix, pH, and container.
Quality control for glutathione focuses on identity, purity, and oxidation state. Certificates of analysis may report assay value, water content, and the presence of GSSG or other impurities. Chromatographic purity is often expressed as a percentage of peak area. Reference standards help laboratories compare results across instruments and batches. Because glutathione is a small, polar molecule, separation from cysteine, gamma-glutamylcysteine, and related thiols can be challenging. Verification often combines more than one analytical technique.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C10H17N3O6S | Reduced glutathione (GSH) |
| Molar mass | 307.32 g/mol | Oxidized dimer GSSG is 612.63 g/mol |
| Appearance | White to off-white crystalline powder | Typical purified solid |
| Solubility | Freely soluble in water; practically insoluble in ethanol | Polarity reflects multiple ionizable groups |
| Common synonyms | GSH; L-glutathione; γ-glutamylcysteinylglycine | 'Reduced' distinguishes it from GSSG |
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.
For solid glutathione reagents, storage at low temperature and protection from moisture and light are typical precautions. Aqueous solutions can oxidize over time, and pH affects stability; alkaline conditions generally promote thiol oxidation. Some protocols prepare fresh solutions, while others use antioxidants or chelators to limit metal-catalyzed oxidation. Purity and counterion content can vary among commercial preparations, affecting concentration calculations. Certificates of analysis and validated assays help verify identity and purity.
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.
Stability depends on pH, temperature, oxygen exposure, and trace metals. Aqueous solutions of reduced glutathione are susceptible to oxidation, especially when neutral or alkaline and exposed to air. Transition metal ions can catalyze thiol oxidation, so chelators and inert atmospheres are sometimes used in research settings. Standards are typically stored cold and desiccated, with limited freeze-thaw cycles. Questions remain about how closely in vitro stability data reflect the behavior of glutathione within intact cells and tissues.
Measuring glutathione requires attention to oxidation during sample handling, because GSH in biological samples can convert to GSSG or form mixed disulfides with proteins after collection. Acidic extraction, rapid cooling, and chelating agents are commonly used to limit such changes. Analytical methods usually distinguish free reduced glutathione, total glutathione, and protein-bound forms. Because these forms have different stability and reactivity, reported values depend heavily on the preparation protocol. No single preparation is universally suitable for every biological matrix or analytical goal.
Several techniques are used for quantification. Enzymatic recycling assays rely on glutathione reductase and a colorimetric or fluorescent readout, offering sensitivity for total glutathione. High-performance liquid chromatography can separate GSH from GSSG and other thiols, often with UV, fluorescence, or electrochemical detection. Mass spectrometry provides structural confirmation and can quantify low-abundance species when paired with separation. Each approach has trade-offs in specificity, throughput, and equipment requirements, so method selection depends on the research question and available instrumentation.
Other researchers of the entities seemingly encountered by DMT users describe them as "entities" or "beings" in humanoid as well as animal form, with descriptions of "little people" being common (non-human gnomes, elves, imps, etc.). Strassman and others have speculated that this form of hallucination may be the cause of alien abduction and extraterrestrial encounter experiences, which may occur through endogenously-occurring DMT. Likening them to descriptions of rattling and chattering auditory phenomena described in encounters with the Hayyoth in the Book of Ezekiel, Rick Strassman notes that participants in his studies, when reporting encounters with the alleged entities, have also described loud auditory hallucinations, such as one subject reporting typically "the elves laughing or talking at high volume, chattering, twittering". Researchers such as Robin Carhart-Harris and David E. Nichols among others believe that DMT entities are merely illusions and hallucinations. However, Andrew Gallimore believes that entity encounters are real and genuine interactions with other-dimensional beings. Neurocomputational models of entity encounters have been proposed, for instance by Carhart-Harris and colleagues.
Narrated by Paul Barry, produced by Daryl Karp, directed by Richard Smith, an Australian production, made by ABC 25 September Cleared for Take-off, the years leading to the first flight of the Boeing 777, planned for May 1995; testing the Boeing 777 APU in cold weather in Alaska; Boeing put £5bn into the testing; Alan Mulally, head of the 777 team; the evangelical management process of 'Working Together', to avoid secrecy; Ronald Ostrowski, director of engineering on the 777; the engines cost 20% of the total cost; Granville Frazier of propulsion; the ETOPS standard for twin-engined aircraft; Chester Ekstrand; the first ever 747 is fitted with a 777 testbed engine; the Pratt Whitney test rig at the Aero-propulsion Systems Test Facility at Tullahoma, Tennessee; Baldey Mehta of the 777 engine; John Cashman, the chief 777 test pilot; the 777 engine testbed has an engine surge, on take off; Thomas Davenport, head of the 777 program for Pratt Whitney; Rocky Thomas of Propulsion; the 777 fuselage is pressurised in January 1994, for the first time from 5 psi to 12 psi; Philip M. Condit; Neil Standal of the fabrication division; Jim McWha of flight testing; Lyle Eveland, head of factory operations; the 777 has its first flight on 12 June 1994, to test the aircraft stability; Frank Shrontz, head of Boeing.
Certificate of Merit (1987) from the Indian Chemical Society for the best paper presentation, at the Convention of Chemists, 1987 2. Special Award and Citation (1988) of the Syndicate of Calicut University, Kerala, India for outstanding research contributions during 1985-1988 3. Swarnajayanti Research Grant (2001), Special research grant to outstanding young researchers by DST, Govt. India 4. Ramanna Fellow, DST (2007) 5. Adjunct Professor, Material Science Programme, IIT, Kanpur 6. Dean, Chemical Sciences, Academy of Scientific and Innovative Research (AcSIR) 7. A. V. Rama Rao Foundation Award Lecture of JNCASR, Bangalore (2012) 8. R. A. Mashelkar Endowment, NCL Pune (2012) 9. Chair on Nanoscience and Nanotechnology, Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam, Kerala, 2013 10. Prof. K. K. M. Yusuff Endowment, Cochin University of Science and Technology, 2013 11. CHEMCON distinguished speaker award, 2016. 12. ISCB-2017 Award given by Indian Society of Chemists and Biologists. Academy Fellowships 1. Fellow, Indian Academy of Sciences, Bangalore (2006) 2. Fellow, National Academy of Sciences, Allahabad, India (2011) 3. Fellow, Indian National Science Academy, New Delhi (2012) 4. Honorary Fellow, Kerala Academy of Sciences (2013) 5. Fellow, Royal Society of Chemistry, London (2014) 6. Fellow, The World Academy of Science (2015) Research Fellowships
Sources: en.wikipedia.org
Professor Dame Melanie Jane Hall (née Davies; born 8 July 1961) is a British physician and academic specialising in type 2 diabetes. She is Professor of Diabetes Medicine at the University of Leicester and an Honorary Consultant Diabetologist at University Hospitals of Leicester NHS Trust. Davies is co-director of the Leicester Diabetes Centre, a collaboration between the University of Leicester and University Hospitals of Leicester NHS Trust, based at Leicester General Hospital.
Size-exclusion chromatography (SEC) is also known as gel permeation chromatography (GPC) or gel filtration chromatography and separates molecules according to their size (or more accurately according to their hydrodynamic diameter or hydrodynamic volume). Smaller molecules are able to enter the pores of the media and, therefore, molecules are trapped and removed from the flow of the mobile phase. The average residence time in the pores depends upon the effective size of the analyte molecules. However, molecules that are larger than the average pore size of the packing are excluded and thus suffer essentially no retention; such species are the first to be eluted. It is generally a low-resolution chromatography technique and thus it is often reserved for the final, "polishing" step of a purification. It is also useful for determining the tertiary structure and quaternary structure of purified proteins, especially since it can be carried out under native solution conditions.
== Research == AAS, alone and in combination with progestogens, have been studied as potential male hormonal contraceptives. Dual AAS and progestins such as trestolone and dimethandrolone undecanoate have also been studied as male contraceptives, with the latter under active investigation as of 2018. Topical androgens have been used and studied in the treatment of cellulite in women. Topical androstanolone on the abdomen has been found to significantly decrease subcutaneous abdominal fat in women, and hence may be useful for improving body silhouette. However, men and hyperandrogenic women have higher amounts of abdominal fat than healthy women, and androgens have been found to increase abdominal fat in postmenopausal women and transgender men as well.
== ABRF Executive Board == Kevin Knudtson, ABRF President, Genomics Division, University of Iowa Justine Kigenyi, Treasurer, KU Medical Center Marie Adams, Van Andel Institute Roxann Ashworth, Johns Hopkins University Kym Delventhal, Stowers Institute for Medical Research Sridar Chittur, SUNY Albany Nick Ambulos, University of Maryland School of Medicine Sue Weintraub, University of Texas Health Science Center at San Antonio Magnus Palmblad, Leiden University Medical Center Ken Schoppmann, ABRF Executive Director
Sources: en.wikipedia.org
== Function == This gene encodes the alpha chain of type XVI collagen, a member of the FACIT collagen family (fibril-associated collagens with interrupted helices). Members of this collagen family are found in association with fibril-forming collagens such as type I and II, and serve to maintain the integrity of the extracellular matrix. High levels of type XVI collagen have been found in fibroblasts and keratinocytes, and in smooth muscle and amnion.
Occupancy of the serotonin transporter with vortioxetine in young men was found to be highest in the raphe nucleus with median occupancies of 25%, 53%, and 98% after 9 days of administration with 2.5, 10, and 60 mg/day vortioxetine. In another study, serotonin transporter occupancy in men was 50%, 65%, and ≥80% for 5, 10, and 20 mg/day vortioxetine respectively. Vortioxetine at 5 mg/day may produce antidepressant effects and result in SERT occupancy as low as 50%. This is in apparent contrast to SSRIs and SNRIs, which appear to require a minimum of 70 to 80% occupancy for antidepressant efficacy. These findings are suggestive that the antidepressant effects of vortioxetine may be mediated by serotonin receptor interactions in addition to serotonin reuptake inhibition. A study found no significant occupancy of the 5-HT1A receptor with vortioxetine at 30 mg/day for 9 days, which suggests that at least this specific serotonin receptor may not be involved in the clinical pharmacology of vortioxetine. However, methodological concerns were noted that may limit the interpretability of this result. Occupancy of other serotonin receptors like 5-HT3 and 5-HT7 by vortioxetine in humans does not seem to have been studied. In relation to the preceding, the contribution of serotonin receptor interactions to the antidepressant effects of vortioxetine is unknown and remains to be established. Uncertainties remain about whether vortioxetine is indeed a clinically multimodal antidepressant or whether it is effectively "[just] another selective serotonin reuptake inhibitor".
Climate change in Brazil is causing higher temperatures and longer-lasting heatwaves, changing precipitation patterns, more intense wildfires and heightened fire risk. Brazil's hydropower, agriculture and urban water supplies will be affected. Brazil's rainforests, and the Amazon, are particularly at risk to climate change. At worst, large areas of the Amazon River basin could turn into savannah, with severe consequences for global climate and local livelihoods. Extreme weather events like droughts and flash floods are causing annual losses of around R$13 billion (US$2.6 billion), equivalent to 0.1% of the country's 2022 GDP. Climate impacts could exacerbate poverty. Brazil's greenhouse gas emissions per person are higher than the global average, and Brazil is among the top 10 highest emitting countries. Greenhouse gas emissions by Brazil are over 4% of the annual world total. In 2026 the Brazilian government has launched a National Climate Change Plan which should cut greenhouse gas emissions by 59% - 67% by 2035, and make the country carbon neutral by 2050. Brazil hosted the 2025 United Nations Climate Change Conference, in which it launched the Global carbon market coalition immediately joined by 11 countries including Brazil, China, the European Union, United Kingdom. According to some calculations, a global carbon market can speed up emission reduction seven-fold.
=== Brazil === The rate of overweight and obesity in Brazilian children increased from 4% in the 1980s to 14% in the 1990s. In 2007 the prevalence of children overweight and childhood obesity was 11.1% and 2.7% in girls, 8.2% and 1.5% in boys, respectively.
=== Optical methods === Directed assembly or more specifically directed self-assembly, can produce a high pattern resolution (~10 nm) with high efficiency and compatibility. However, when using DSA in high volume manufacturing, one must have a way to quantify the degree of order of line/space patterns formed by DSA in order to reduce defect. Normal approaches, such as critical dimension-scanning electron microscopy (CD-SEM), to obtain data for pattern quality inspection take too much time and is also labor-intensive. On the other hand, the optical scatterometer-based metrology is a non-invasive technique and has very high throughput due to its larger spot size. These result in the collection of more statistical data than by using SEM, and that data processing is also automated with the optical technique making it more feasible than traditional CD-SEM.
Sources: en.wikipedia.org
It is a tripeptide rather than a full protein. Proteins generally contain many amino acids joined by alpha-peptide bonds, while glutathione has three residues and an unusual gamma-glutamyl linkage. That structure affects how enzymes recognize and break it down.
GSH is the reduced form with a free thiol group. GSSG is the oxidized disulfide dimer formed when two GSH molecules react. The GSH-to-GSSG ratio is used in research as one indicator of cellular redox conditions.
Yes, it is present in many animal and plant tissues, including meats, some vegetables, and fruits. Heat, storage, and processing can reduce its content, so measured amounts vary widely.
Common methods include spectrophotometric enzyme cycling assays, HPLC with UV or fluorescence detection, and LC-MS/MS. Detection often requires derivatization because glutathione lacks a strong chromophore. Method choice depends on the sample type and the required sensitivity.