Aging brain microenvironment decreases hippocampal neurogenesis through Wnt-mediated survivin signaling

作者：Miranda Carlos J; Braun Lyndsey; Jiang Yuying; Hester Mark E; Zhang Ling; Riolo Matthew; Wang Haijuan; Rao Meghan; Altura Rachel A; Kaspar Brian K^*

来源：Aging Cell, 2012, 11(3): 542-552.

DOI：10.1111/j.1474-9726.2012.00816.x

• adult neurogenesis
• aging
• astrocytes
• survivin
• Wnt signaling

Accumulating evidence suggests that adult hippocampal neurogenesis relies on the controlled and continued proliferation of neural progenitor cells (NPCs). With age, neurogenesis decreases through mechanisms that remain unclear but are believed to involve changes in the NPC microenvironment. Here, we provide evidence that NPC proliferation in the adult brain is in part regulated by astrocytes via Wnt signaling and that this cellular cross-talk is modified in the aging brain, leading to decreased proliferation of NPCs. Furthermore, we show that astrocytes regulate the NPC cell cycle by acting on the expression levels of survivin, a known mitotic regulator. Among cell cycle genes found down-regulated in aged NPCs, survivin was the only one that restored NPC proliferation in the aged brain. Our results provide a mechanism for the gradual loss of neurogenesis in the brain associated with aging and suggest that targeted modulation of survivin expression directly or through Wnt signaling could be used to stimulate adult neurogenesis.

• 出版日期2012-6