Changes in glutathione and its metabolizing enzymes in human erythrocytes and lymphocytes with age.

The levels of glutathione (GSH) and the activities of glutathione S-transferases (GST) and glutathione reductase (GSR) in human erythrocytes and lymphocytes were determined in three age groups (5-12, 25-40, 65-83 years). The levels of GSH in lymphocytes increased with age, however, its levels in erythrocytes reached a maximum in the middle age group. The activity of GST in erythrocytes and lymphocytes changed as a function of age in a pattern similar to the changes found for GSH levels. GSR activity increased from young to middle age in both erythrocytes and lymphocytes, but decreased again in the old age group.