Glutathione

Overview

Glutathione is a tripeptide (gamma-L-glutamyl-L-cysteinyl-glycine) that serves as the principal intracellular antioxidant in mammalian cells. Researchers study it for oxidative stress defense, xenobiotic detoxification, immune cell function, and redox signaling.

Mechanism of Action

Glutathione cycles between reduced (GSH) and oxidized (GSSG) forms, donating electrons to reactive oxygen species via glutathione peroxidase. It serves as a cofactor for glutathione S-transferases (GSTs) in Phase II detoxification, maintains reduced protein thiols, supports T-cell proliferation and NK cell cytotoxicity, and regenerates vitamins C and E.

Research Summary

IV glutathione was studied in a randomized, double-blind trial for Parkinson's disease (Hauser et al., Movement Disorders, 2009), confirming safety at 1400mg three times weekly. A Phase II trial of nebulized glutathione in cystic fibrosis showed modest FEV1 improvement (Griese et al., Journal of Cystic Fibrosis, 2013). Oral bioavailability is limited, driving investigation of IV, nebulized, and liposomal delivery.

Dosing Information

Reported Side Effects

• Bloating and abdominal cramps (oral administration)
• Zinc depletion with prolonged high-dose use
• Bronchospasm (inhaled formulations)
• Transient skin lightening at high systemic doses

Research References

• Randomized, double-blind, pilot evaluation of intravenous glutathione in Parkinson's disease (2009)
• Regulation of glutathione synthesis (2009)
• Inhalation treatment with glutathione in patients with cystic fibrosis. A randomized clinical trial (2013)