Plasma total glutathione concentrations in healthy pediatric and adult subjects.

Glutathione, as a free radical scavenger, plays an important role in protecting cells against oxidative damage. Since aging is associated with decreased plasma glutathione levels, we investigated plasma concentrations of total glutathione (including the reduced and oxidized forms, tGSH=GSH+GSSG) and total cysteine in 129 healthy pediatric and adult subjects. Plasma tGSH concentrations were significantly lower in infants than in adults. There were no significant differences in plasma tGSH concentrations between the children and adult group. No significant differences in plasma total cysteine concentrations were found between any pediatric and adult group. We conclude that lower plasma tGSH levels in pediatric subjects may reflect greater oxidative stress during the neonatal and infant period.