Adult hippocampal neurogenesis: New avenues for treatment of brain disorders.

Abstract

Neurogenesis, the biological process of forming new neurons, was traditionally believed to occur only during embryonic stages in the mammalian central nervous system for a long time. Over the past few decades, due to the development of new techniques and the accumulation of supportive evidence, adult neurogenesis is now accepted as the one of the most robust forms of plasticity in the adult brain, which contributes to physiological function as well as a range of neurological or psychiatric disorders. In this review, we mainly concentrate on adult neurogenesis in the hippocampus, the most likely neurogenic niche with significant roles in various brain functions. We begin by summarizing the current fundamental knowledge of adult hippocampal neurogenesis including proliferation, differentiation, maturation, and synapse formation of neural stem cells. We then focus on the potential roles of these adult-born neurons and their contribution to learning and memory behaviors and their relevance to various diseases. Furthermore, we review regulatory mechanisms governing adult hippocampal neurogenesis, including local environmental cues, multiple molecular signaling pathways, and neural network activities. We also discuss possible therapeutic strategies and targets that can be leveraged for future clinical translations. Finally, given the substantial progress in the field of regenerative medicine aimed at harnessing the multipotent resident cells for brain repair, we address remaining challenges and propose our perspectives on future directions for treating central nervous system disorders.