S-ALLYLMERCAPTOCYSTEINE, A STABLE THIOALLYL COMPOUND, INDUCES APOPTOSIS IN ERYTHROLEUKEMIA CELL-LINES

The antiproliferative potential of S-allylmercaptocysteine (SAMC), a s table organosulfur compound of aged garlic extract, has been investiga ted using two erythroleukemia cell lines, HEL and OCIM-1. It induced a dose-dependent inhibition of cell growth with a 50% lethal dose of 0. 046 mM for OCIM-1 cells and 0.093 mM for HEL cells. [H-3]thymidine inc orporation was reduced in cells treated with this thioallyl compound, and analysis of high-molecular-weight DNA showed fragmentation compati ble with apoptosis. Flow cytometric analyses of DNA revealed an abnorm al cell cycle progression in both types of erythro leukemia cells, wit h the major portion of the unsynchronized cells in the G2/M phase. Mea surement of acid-soluble free sulfhydryl groups showed an initial incr ease in response to SAMC followed by with extended incubation of cells . We conclude from these studies that SAMC is an effective antiprolife rative agent against erythroleukemia cells that induces cell death by apoptosis.