Glutathione (GSH) is a tripeptide (λ-glutamyl-cysteinylglycine) synthesized by most cells, serving as a critical marker of cellular health and resilience against toxic stress. In erythrocytes, GSH levels are a sensitive indicator of the body's intracellular GSH status and overall cellular well-being. It is the most abundant non-protein thiol in mammalian cells, playing key roles in various biological processes, such as detoxifying harmful compounds (xenobiotics), neutralizing reactive oxygen species, regulating cellular redox balance, and maintaining the oxidative state of vital protein sulfhydryl groups. Additionally, GSH supports immune function. Intracellular GSH concentrations are significantly higher than plasma levels, with plasma GSH largely derived from the liver. The active form, reduced GSH (rGSH), is maintained at a ratio of approximately 9:1 with its oxidized counterpart (GSSH) in healthy cells. However, once a blood sample is collected, erythrocyte rGSH is highly prone to oxidation, rapidly diminishing the rGSH ratio. Due to the impracticality of preventing ex vivo oxidation and the challenges of directly measuring rGSH in clinical settings, it is more feasible to assess total erythrocyte GSH as an indicator of overall GSH status. Research suggests that an unfavorable rGSHratio is closely associated with abnormally low total cellular GSH levels.
Glutathione; Erythrocytes
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