P2X7-induced apoptosis decreases by aging in mice myeloblasts

In the current study, the ability of ATP to promote apoptosis in myeloblasts at different ages was investigated. We have observed that high concentration of extracellular ATP (>1 mM), which activates P2X7 receptor, produced cell shrinkage an increase in the number of events in the sub-G0/G1 region of the cellular cycle and annexin-V/propidium iodide label, which characterizes the apoptotic cell death. In addition, BzATP produced apoptosis, but not ADP and UTP. Gr-1+ cells express the P2X7 receptor and oxidized ATP, a specific P2X7 inhibitor, blocked the ATP-dependent apoptosis. ATP-dependent apoptosis is decreased by aging in myeloblasts of 12 and 22-month-old mice. Furthermore, P2X7 expression decrease was observed in older mice, explaining apoptosis decrease. This decrease in apoptosis by aging may be related to some diseases in the myelocyte lineage.