Glutathione, Reduced (GSH) Monograph

Introduction Reduced glutathione, most commonly called glutathione or GSH, is a relatively small molecule ubiquitous in living systems. Occurring naturally in all human cells, GSH is a water-phase orthomolecule. Its intracellular depletion ultimately results in cell death and its clinical relevance has been researched for decades. GSH is the smallest intracellular thiol (–SH) molecule. Its high electron-donating capacity (high negative redox potential) combined with high intracellular concentration (millimolar levels) generate great reducing power. This characteristic underlies its potent antioxidant action and enzyme cofactor properties, and supports a complex thiol-exchange system, which hierarchically regulates cell activity. GSH levels in human tissues normally range from 0.1 to 10 millimolar (mM), most concentrated in the liver (up to 10 mM) and in the spleen, kidney, lens, erythrocytes, and leukocytes. Plasma concentration is in the micromolar range (approx. 4.5 μM). Oxidative stressors that can deplete GSH include ultraviolet and other radiation; viral infections; environmental toxins, household chemicals, and heavy metals; surgery, inflammation, burns, septic shock; and dietary deficiencies of GSH precursors and enzyme cofactors.