Iron overload induces ROS-mediated neural stem/progenitor cells apoptosis via mTOR pathway.

Intracerebral hemorrhage (ICH) is a health challenge resulting in death or disability. Iron overload has been identified as one of post-ICH damaging factors. However, the impact of iron overload, as well as the underlying mechanisms, on neural stem/progenitor cells (NSPCs) remains unknown. In this study, we found that iron overload induced significant NSPC death in a dose-dependent manner. Interestingly, iron overload increased the number of early and late apoptotic cells and the expression of caspase-3 in NSPCs. Moreover, iron overload was highly correlated with enhanced intracellular reactive oxygen species (ROS) generation and loss of mitochondrial integrity. Further, iron overload activated mTOR signaling and downregulated AMP-activated protein kinase (AMPK) phosphorylation. Importantly, drugs that eliminate ROS or activate AMPK prevented this event, as well as apoptosis of NSPCs. These results indicate that post-ICH iron overload in the brain induces excessive ROS generation and leads to NSPC death by regulating mTOR and AMPK signaling.