Notch signaling and neurogenesis in normal and stroke brain.

Adult neuronal stem cells (NSCs) hold great promise for brain repair because of their unique location within the central nervous system, their potential to proliferate and to differentiate into all major neural lineages, and their ability to functionally incorporate into existing neuronal circuitry after stroke. Nevertheless, the ability to exploit these cells for therapeutic purposes is hampered by the lack of knowledge about the signals that control the generation of a functional neuron from adult NSCs after stroke, particularly in the aged brain. Therefore, to further define the regulatory mechanisms that underlie neurogenesis after stroke, it is critically important to develop future NSC-based repair strategies. Notch signaling defines a fundamental pathway controlling cell fate acquisition. Studies have shown that Notch signaling pathways play critical roles during the maintenance, proliferation, and differentiation of NSCs in the developing brain. Recent evidence shows that Notch1 signaling is conserved in the regulation of adult neurogenesis. Here we summarize current knowledge about the role of Notch signaling in the regulation of neurogenesis in the normal and stroke brain.