EFFECT OF AGE ON THE FATTY-ACID COMPOSITION OF PHOSPHOLIPIDS IN HUMAN-LYMPHOCYTES

We have examined the fatty acid composition of phospholipids of unstim ulated and PHA-stimulated T cells from young and old donors. Our resul ts demonstrate that aging is accompanied by decreases in the saturated fatty acids, myristic acid, and palmitic acid, and a concomitant incr ease in the unsaturated arachidonic acid, Following activation with PH A for 24 h, age-associated differences in fatty acids could no longer be detected, In contrast to the lymphocyte, aging did not affect the f atty acid composition of either serum or neutrophil phospholipids. Exp osure of lymphocytes from old donors to myristic acid complexed medium increased the levels of myristate in the phospholipids to levels simi lar to that seen in lymphocytes from young donors. We conclude from th ese studies that aging is accompanied by an alteration in the fatty ac id profiles of phospholipids, and that incubation in myristic acid com plexed medium modulates these profiles. These alterations are unique t o lymphocytes and may contribute to the age-related declines in lympho cyte function.