What is glutathione?
Glutathione is the most abundant antioxidant made inside our cells. Here is what it is, how cells make and recycle it, and why it is central to research on oxidative stress.
At a glance
- Full name
- γ-L-glutamyl-L-cysteinylglycine
- Forms
- Reduced (GSH) and oxidised (GSSG)
- Molecular formula
- C10H17N3O6S
- Molecular weight
- ≈ 307.3 g/mol
- CAS number
- 70-18-8
- Appearance
- White lyophilized powder
- Our fill size
- 1200mg
A tripeptide with an unusual bond
Glutathione is made of three amino acids: glutamate, cysteine and glycine. Unlike most peptides, the glutamate is joined through its side chain (a γ-glutamyl bond) rather than its usual backbone, which protects glutathione from most of the enzymes that break down peptides. The working part is the cysteine's thiol group, which can give up electrons to neutralise oxidants. Glutathione is the most abundant non-protein thiol in mammalian cells and is found in every tissue.2
How cells make it
Cells build glutathione in two energy-using steps in the cytosol. Glutamate-cysteine ligase first joins glutamate and cysteine; this is the rate-limiting step. Glutathione synthetase then adds glycine. The supply of cysteine and the activity of glutamate-cysteine ligase are the main factors that control how much glutathione a cell can make.2
What it does in the cell
Neutralising oxidants
Glutathione protects cells from oxidative damage and helps keep their redox balance.1 Enzymes called glutathione peroxidases use it to reduce hydrogen peroxide and lipid peroxides; in the process two glutathione molecules are joined into the oxidised form, GSSG, which glutathione reductase then recycles back to GSH.
Clearing toxins
Glutathione S-transferases attach glutathione to reactive electrophiles, including many drug metabolites and environmental chemicals, which marks them for removal from the cell.1
Redox signalling
Beyond protection, glutathione helps regulate redox signalling, and through it cell proliferation, programmed cell death and immune function.2
Why the GSH/GSSG ratio matters
Because glutathione cycles between its reduced and oxidised forms, the ratio of GSH to GSSG is one of the most widely used markers of a cell's oxidative state: a falling ratio signals oxidative stress. Measuring it accurately is harder than it sounds, because GSH can oxidise during sample handling, so methods for measuring glutathione are a research topic in their own right.1
Where glutathione is used in the lab
Glutathione is a standard reagent in research on oxidative stress, detoxification and conjugation chemistry, and cell protection. It is often studied alongside other compounds in cellular-health research, such as NAD+, the mitochondria-targeted peptide SS-31, and the copper peptide GHK-Cu.
Handling glutathione in the lab
Lyophilized glutathione is stable stored frozen at −4 °F and protected from light. Let a vial reach room temperature before opening, reconstitute with bacteriostatic water added slowly down the side of the vial, swirl rather than shake, and keep the solution refrigerated at 36–46 °F. Reduced glutathione oxidises in solution over time, so prepare solutions fresh where possible and keep them cold.
Before using any lot, check its certificate of analysis. Our current glutathione lot, VD-GSH1200-2610, tested at 99.30% purity by HPLC with identity confirmed by LC-MS at VeriPure Labs. View the certificate ↗ or see every lot on our lab reports page.
Frequently asked questions
What is the difference between GSH and GSSG?
GSH is reduced glutathione, the active antioxidant form. When it neutralises an oxidant, two GSH molecules join to form oxidised glutathione, GSSG, which cells recycle back to GSH.
What limits how much glutathione cells make?
Mainly the supply of the amino acid cysteine and the activity of glutamate-cysteine ligase, the enzyme that carries out the first step.
Why is the GSH/GSSG ratio used in research?
Because glutathione shifts toward its oxidised form under oxidative stress, the ratio of GSH to GSSG is a standard marker of a cell’s redox state.
Is research glutathione for human use?
No. Vivid DNA supplies glutathione strictly for laboratory research. It is not a drug, food or supplement, and is not for human or veterinary use.
References
- Forman HJ, Zhang H, Rinna A. Glutathione: overview of its protective roles, measurement, and biosynthesis. Molecular Aspects of Medicine. 2009;30(1–2):1–12. PubMed 18796312 ↗
- Lu SC. Glutathione synthesis. Biochimica et Biophysica Acta. 2013;1830(5):3143–3153. PubMed ↗
More research overviews
Research use only. Vivid DNA products are sold strictly for laboratory research. They are not drugs, foods, cosmetics or supplements, are not for human or veterinary use, and are not intended to diagnose, treat, cure or prevent any disease. Clinical results described here refer to investigational or approved medicines studied under medical supervision, not to research-grade material. This article summarises published research and has not been evaluated by the Food and Drug Administration.