Apoptosis-inducing activity of galloyl monosaccharides in human histiocytic lymphoma U937 cells

Three galloyl monosaccharides contained in medicinal plants were examined for apoptosis-inducing activity in human histiocytic lymphoma U937 cells. Tetragalloyl glucose (TgG) induced apoptosis as found by chromatin condensation, DNA ladder formation, and inhibition by a caspase inhibitor. Digalloyl hamamelose had moderate activity, while monogalloyl glucose was only marginally active. These findings suggest that the number and disposition of their phenolic groups are important for apoptosis induction. TgG induced apoptosis in human colon and stomach cancer cell lines as well, indicating it is potentially useful as an anti-cancer agent.