X-ray irradiation accelerates senescence in hippocampal neural stem/progenitor cells via caspase-1 activation

Despite the effectiveness in controlling the progression of brain tumors, cranial irradiation often causes neuropsychological deficits in cancer survivors. Inflammation is considered a major cause of tissue injury from irradiation. The caspase-1 activation complexes (inflammasomes) can facilitate caspase-1 and IL-1β processing, which amplifies the inflammatory response. In the present study we examined whether caspase-1 activation contributes to irradiation-induced damage to neural stem and progenitor cells (NSPCs). We found that X-ray irradiation induced activation of caspase-1 in NSPCs in vitro and in vivo. Next, using a caspase-1 inhibitor (Ac-YVAD-CMK) to block caspase-1 activation in vitro and in vivo, we further demonstrated that X-ray irradiation may inhibit proliferation, induce senescence of NSPCs through caspase-1 activation. Together, our results suggest that caspase-1 activation is involved in irradiation-induced damage to NSPCs.