Glutathione
Overview
Glutathione is a tripeptide antioxidant synthesized intracellularly that maintains cellular redox balance, detoxifies xenobiotics, and regenerates vitamins C and E. As the most abundant non-protein thiol, it exists in reduced (GSH) and oxidized (GSSG) forms, with the GSH:GSSG ratio reflecting oxidative stress status. Low levels indicate oxidative stress, chronic inflammation, liver disease, or malnutrition, while direct clinical measurement has limited routine utility. Glutathione assessment is primarily research-focused for oxidative stress biomarkers rather than standard clinical diagnostics.
Clinical Use Cases
- Research evaluation of oxidative stress in chronic diseases.
- Assessment of liver detoxification capacity in toxicology.
- Monitoring nutritional glutathione status in critical illness.
- Limited clinical use; primarily investigational for neurodegenerative diseases.
Specimen Types
- Whole blood (for erythrocyte glutathione).
- Plasma (total glutathione).
- Tissue biopsy (research).
Measurement Methods
- High-performance liquid chromatography (HPLC) with fluorescence or electrochemical detection.
- Enzymatic recycling assay (DTNB-GR method).
- Mass spectrometry for GSH/GSSG ratio.
Test Preparation and Influencing Factors
- Avoid acetaminophen and alcohol prior to testing.
- Recent oxidative stress, inflammation, or critical illness depletes levels.
- N-acetylcysteine supplementation elevates glutathione.
- Sample processing critical: immediate acidification prevents GSH auto-oxidation.
Synonyms
- GSH.
- Reduced glutathione.
- L-gamma-glutamyl-L-cysteinylglycine.