Amino Acid Metabolism of Platelets in Leukemia¹

Platelets from patients with acute myelogenous leukemia, both before and after remission induction, were evaluated for their ability to incorporate d-[U-¹⁴C]glucose into the four amino acids, glutamine, asparagine, glutamic acid, and aspartic acid. Normal platelets incorporated about 80% of the activity into the amides, glutamine and asparagine, and only 20% into their respective amino acids, glutamic acid and aspartic acid. Platelets from patients with acute myelogenous leukemia in the acute stage showed a reversal of this pattern, which then returned to normal during remission. However, the concentration of amino acids was higher than normal, suggesting that remission platelets behaved like a young cell population. The abnormal pattern of labeling could be interpreted as a defect in the platelet citric acid cycle thereby compromising its energy source.