Induction of Apoptosis of HL60 Cells by Gallic Acid Derivatives

Abstract

Induction of apoptosis of HL60 cells by gallic acid derivatives was analyzed in relation to its prooxidant action. Gallic acid esters with long hydrophobic alcoholic chain showed potent apoptotic activity. Octyl-and laurylgallates induced apoptotic cell death of HL60, whereas gallic acid, ethyl-, propyl-and butylgallates caused only a little apoptosis. Octylgallate inactivated aconitase prior to the induction of apoptosis of the cells. Treatment of cells with antibodies to Fas and TNF did not affect the octylgallate-mediated apoptosis, suggesting that Fas or TNF signaling pathway is not responsible for the apoptosis by gallate derivatives. Gallic acid esters with hydrophobic chains can generate superoxide radical and then hydroxyl radical through the inactivation of aconitase in cells. Gallate esters-dependent formation of reactive oxygen species may participate in the apoptosis of HL60 cells.