Induction of Neurogenesis in Neocortex for Brain Repair

描述（由申请人提供）：拟议的长期目标 修复受损的新皮层回路。我们之前的很多 工作集中于通过移植未成熟的神经元和神经元的修复， 前体然而，最近，我们已经操纵了内源性前体， 原位在成年小鼠进行神经发生和解剖电路 在新皮层重新形成，在那里它通常不会发生，这 没有移植。这项工作的最终目标是修复 通过在原位操纵内源性神经前体。这可能导致 皮质退行性、发育性或获得性疾病的治疗方法， 其输出电路（例如脊髓）。在新皮层， 这种未来的疗法可能关键取决于内源性前体， 或干细胞，可以精确地诱导形成新的神经元;迁移到正确的 位置;适当区分和整合;并重新形成精确的 长距离投影和复杂的功能连接。 神经母细胞和神经前体细胞对 大脑皮层的局部信号分子 生物药理学诱导的投射神经元凋亡。它们选择性地迁移 分化成投射神经元，接受突触 输入，并重新形成远程电路。 虽然我们在确定 皮质神经发生和皮质回路的部分修复是可能的， 成年人，许多问题仍然有待调查。这些问题形成 建议研究的基础：1）我们可以大幅增加数量 新的皮质神经元的增殖/分化， 内源性前体和/或新生神经元的存活？2)新生的神经元 精确地分化成新的功能投射神经元， 传入突触，并成为功能整合？3)有哪些 负责诱导神经发生的分子机制和特异性 成人新皮层的内源性前体分化？我们的三 具体目标将直接测试和调查这些问题。提出 实验将：目的1）确定选择候选生长的影响 增加新皮质中诱导神经发生量的因素 成年小鼠;目的2）研究新生神经元分化的精确性 通过分析神经递质和受体补体以及突触 整合，使用共聚焦和免疫细胞化学;和目的3）研究 通过微阵列分析这种诱导神经发生的分子机制， 差异基因表达，候选物的确认，以及体外 功能测定这些实验将一起研究 成年小鼠新皮层中诱导神经发生的潜在机制; 显著增加神经发生量的潜力;以及 来自内源性前体的新生皮质神经元的能力， 修复皮层回路

DESCRIPTION (provided by applicant): The long-term goal of the proposed experiments is the repair of damaged neocortical circuitry. Much of our prior work has focused on repair by transplantation of immature neurons and neural precursors. Recently, however, we have manipulated endogenous precursors in situ in the adult mouse to undergo neurogenesis and anatomic circuit re-formation de novo in the neocortex, where it does not normally occur, This was without transplantation. This work aims toward the ultimate goal of repair by manipulation of endogenous neural precursors in situ. This could lead to therapies for degenerative, developmental, or acquired diseases of cortex and its output circuitry (e.g. spinal cord). In neocortex, the effectiveness of such future therapies could depend critically on whether endogenous precursors, or stem cells, can be precisely induced to form new neurons; migrate to correct locations; differentiate and integrate appropriately; and re-form precise long-distance projections and complex functional connections. Neuroblasts and neural precursors respond specifically to altered expression of local signal molecules in regions of cortex undergoing synchronous biophysically-induced apoptosis of projection neurons. They selectively migrate into such regions, differentiate into projection neurons, receive synaptic input, and re-form long-distance circuitry. Though we have made considerable progress in identifying conditions under which cortical neurogenesis and partial repair of cortical circuitry is possible in the adult, many questions still remain to be investigated. These questions form the basis of the proposed research: 1) Can we substantially increase the number of new cortical neurons by manipulating proliferation/differentiation of endogenous precursors &/or survival of newborn neurons? 2) Can newborn neurons differentiate precisely into new functional projection-neurons, receive afferent synapses, and become functionally integrated? 3) What are the molecular mechanisms responsible for inducing neurogenesis and specific differentiation by endogenous precursors in the adult neocortex? Our three specific aims will test and investigate these questions directly. Proposed experiments will: Aim 1) determine the effects of select candidate growth factors toward increasing the amount of induced neurogenesis in neocortex of adult mice; Aim 2) investigate the precision of newborn neuron differentiation by analysis of neurotransmitter and receptor complement and synaptic integration, using confocal and immunocytochemistry; and Aim 3) investigate the molecular mechanisms of this induced neurogenesis via microarray analysis of differential gene expression, confirmation of candidates, and in vitro functional assay. Together, these experiments will investigate the molecular mechanisms underlying induced neurogenesis in the adult murine neocortex; the potential for substantially increasing the amount of neurogenesis; and the ability of newborn cortical neurons derived from endogenous precursors to repair cortical circuitry.