Neuroreplacement strategies by mesenchymal stem cell

描述(由申请人提供)： 在我们之前的研究中，人神经干细胞(HNSCs)在体外增殖了一年多，并移植到24月龄大鼠的大脑中，迁移并分化为神经细胞，显著改善了这些动物的认知功能。尽管作为胎儿神经组织的替代品，HNSCs是一种有价值的可移植材料来源，但理想的替代疗法是自体移植。由于我们已经成功地从人类间充质干细胞(HMeSCs)中培养出神经细胞，我们建议将HMeSC用于神经替代治疗。我们的长期目标是确定干细胞谱系的调节机制，并利用从个体患者分离的HMeSCs建立神经替代疗法。这一应用的中心假设是，用溴脱氧尿苷(BrdU)处理的HMeSCs产生的神经细胞在功能上类似于hNSC来源的细胞。该项目的目标是寻找干细胞谱系调控机制的线索，并收集使用HMeSCs进行最佳神经替代疗法的基础数据。目的1.研究BrdU对MESCs神经分化的影响。目的2.成人脑内移植后HMeSC迁移分化的时程评价。目的3.探讨MESC移植是否能改善老年记忆障碍大鼠的认知功能。目的4.在阿尔茨海默病损伤模型中，研究MeSCs高效神经替代是否存在特定的时间窗。这项拟议的研究具有创新性，因为它专注于一种生物功能的能力，即使用BrdU来改变MeSCs的谱系，这可能有助于神经替代策略中的自体移植。这项建议预计将有下列结果：(1)证明BrdU治疗通过DNA甲基化修饰改变HMeSC谱系在体外产生神经细胞；(2)证明经BrdU治疗的HMeSC在i.c.v移植后在成年大脑中分化并迁移到其适当位置；(3)通过HMeSC移植在老年动物模型中恢复认知功能；以及(4)在阿尔茨海默病损伤模型中替换神经元。这项研究有望为通过自体移植治疗神经退行性疾病的MeSCs移植的临床应用提供基础数据。因此，拟议的研究有望在治疗策略上取得突破。

DESCRIPTION (provided by applicant): In our previous study, human neural stem cells (HNSCs), proliferated in vitro for more than a year and transplanted into 24-month-old rat brains, migrated and differentiated into neural cells, and significantly improved the cognitive functions of these animals. Although HNSCs are a valuable source of transplantable material as an alternative to fetal neural tissue, the ideal replacement therapies would be the autologous transplantation. Since we have succeeded in producing neural cells from human mesenchymal stem cells (HMeSCs}, we propose the use of HMeSC for neuroreplacement therapies. Our long-range goal is to identify the regulation of the mechanisms of stem cell lineage and to establish neuroreplacement therapy using HMeSCs isolated from individual patients. The central hypothesis of this application is that HMeSCs treated with bromodeoxyuridin (BrdU) produce neural cells that are functionally similar to HNSC-derived cells. The objectives of this project are to find clues for the regulation of mechanisms for stem cell lineage, and to collect basic data for optimal neuroreplacement therapies using HMeSCs. Aim 1. Investigation of the effects of BrdU on neural differentiation of MeSCs. Aim 2. Time-course assessment of HMeSC migration and differentiation after transplantation into the adult brain. Aim 3. To investigate whether MeSC transplantation improves the cognitive functions of aged memory-impaired rats. Aim 4. To investigate whether there is a specific temporal window for efficient neuroreplacement by MeSCs in an Alzheimer's disease lesion model. The proposed research is innovative, because it focuses on the ability of a biological function; i.e., the use of BrdU, to change the lineage of MeSCs, which may facilitate autologous transplantation in neuroreplacement strategies. This proposal is expected to have the following outcomes: (1) a demonstration that BrdU treatment alters HMeSC lineage to produce neural cells in vitro by DNA methylation modification; (2) a demonstration that BrdU-treated HMeSCs differentiate and migrate into their proper position in the adult brain after i.c.v, transplantation; (3) a recovery of cognitive function by HMeSC transplantation in an aged animal model; and (4) a replacement of neurons in an Alzheimer's disease lesion model. The proposed research is expected to provide fundamental data to develop clinical applications for MeSCs transplantation in patients with neurodegenerative diseases through autologus transplantation. Thus, the proposed studies are expected to make a breakthrough in therapeutic strategies.