Glutathione

Overview

Glutathione (L-gamma-glutamyl-L-cysteinyl-glycine, abbreviated GSH) is a 307 Da tripeptide synthesized endogenously in virtually all mammalian cells, with the highest concentrations found in hepatocytes (5-10 mM), where it serves as the principal intracellular thiol antioxidant and the primary substrate for Phase II detoxification conjugation reactions. At the molecular level, glutathione's cysteine sulfhydryl group (-SH) functions as the active electron donor, directly neutralizing reactive oxygen species (ROS) including superoxide, hydroxyl radicals, and peroxynitrite, while the gamma-peptide bond between glutamate and cysteine confers resistance to conventional peptidase degradation. Published peer-reviewed research demonstrates that GSH serves as an essential cofactor for glutathione peroxidase (GPx) in reducing hydrogen peroxide and lipid hydroperoxides, for glutathione S-transferase (GST) in conjugating electrophilic toxins and drug metabolites for biliary and renal excretion, and for the glutathione-ascorbate cycle that regenerates oxidized vitamin C back to its active reduced form. Injectable glutathione bypasses the near-complete gastrointestinal degradation that limits oral bioavailability, delivering intact GSH directly to the systemic circulation where it can replenish depleted intracellular pools. What distinguishes injectable glutathione from oral N-acetylcysteine (NAC) or liposomal glutathione supplements is the direct delivery of the complete, reduced tripeptide without requiring intracellular synthesis from precursors. Current scientific investigation spans oxidative stress-related pathologies, hepatoprotection, neurodegenerative disease models, immune cell optimization, and the well-documented decline of endogenous GSH levels with advancing age.

Research Applications

Frequently Asked Questions