Antiapoptotic and proapoptotic action of various amino acids and analogs in starving MOLT-4 cells

This study is based on our previous findings showing that certain amino acids may protect hybridoma cells against starvation-induced apoptosis. In the present work we have screened 44 amino acids and analogs for their capacity of modulating apoptosis in human T-lymphoblastic leukemia cell line MOLT-4 exposed to starvation in a nutrient-poor medium. The panel of tested substances was found to contain not only compounds with antiapoptotic activity (e.g., L-glutamine, L-histidine, glycine, L-proline, and L-2-aminopentanoic acid), but also compounds with proapoptotic activity (e.g., L-phenylalanine, L-tryptophan, L-arginine, and L-2-aminohexanoic acid). The apoptosis-modulating effects were dependent on fine details of the structure of the compounds. A switch from antiapoptotic activity to proapoptotic activity was found between 6-aminohexanoic acid and 7-aminoheptanoic acid, as well as between L-2-aminopentanoic acid and L-2-aminohexanoic acid. D-amino acids tested were without effect. (C) 2002 Elsevier Science.