HIF-1? IN VASCULOTROPHIC SUPPORT OF NEURAL STEM CELLS FOLLOWING CEREBRAL ISCHEMI

HIF-1？

• 批准号: 8167446
• 负责人: Tamara Roitbak
• 金额: $ 24.1万
• 依托单位: UNIVERSITY OF NEW MEXICO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8167446
• 关键词: Address; Biochemical; Brain; Cell Separation; Cell Survival; Cell Transplants; Cell physiology; Cells; Cellular biology; Cerebrum; Coculture Techniques; Computer Retrieval of Information on Scientific Projects Database; Confocal Microscopy; Contrast Media; Endothelial Cells; Exhibits; Funding; Gene Deletion; Gene Silencing; Grant; Hypoxia; Immunofluorescence Immunologic; In Vitro; Institution; Ischemia; Knockout Mice; Lead; Magnetic Resonance Imaging; Mediating; Methods; Modeling; Molecular; Morphogenesis; Pathway interactions; Property; Rattus; Recovery; Research; Research Personnel; Resources; Role; Signal Transduction; Source; Stem cells; Stroke; Therapeutic; Tissues; Transcription Coactivator; Transplantation; United States National Institutes of Health; Vascular Endothelial Growth Factors; angiogenesis; brain remodeling; cell type; hypoxia inducible factor 1; knockout animal; nanoparticle; nerve stem cell; neuromechanism; relating to nervous system; response; stem; tool; transcription factor

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Background Utilization of neural stem/progenitor cells (NSPCs) is regarded as a possible therapeutic tool for promoting brain recovery following stroke. We had demonstrated that NSPCs exhibit a strong ability to support endothelial cell survival, morphogenesis and angiogenesis following ischemia. Our study of the molecular mechanisms of NSPC-mediated protection, lead us to a major discovery that the vasculotrophic effect of NSPCs is mediated via activation of the HIF-1a/VEGF pathway. Hypoxia-inducible factor-1 alpha subunit (HIF-1a) is a transcriptional activator mediating adaptive cellular response to hypoxia. Normally degraded in most cell types and tissues, HIF-1a becomes stable and transcriptionally active under conditions of hypoxia. In contrast, we found that HIF-1a is constitutively expressed in NSPCs, regulating expression and pro-angiogenic signaling of the vascular endothelial growth factor (VEGF). These findings lead to our central hypothesis that neural stem cells provide protection for brain endothelial cells and support functional remodeling of the brain vasculature following ischemia. We propose that vasculotrophic properties of NSPCs are governed by transcription factor HIF-1¿, both under normal conditions and following hypoxia. Aims To address our hypothesis, we proposed to study the role of HIF-1¿ signaling in NSPC function and to determine the effects of NSPC-specific HIF-1¿ gene deletion on stroke-induced angiogenesis. Our main approach is to study functional changes in the brain vasculature following experimental focal ischemia, using magnetic resonance imaging (MRI) and superparamagnetic nanoparticles (SPIOs) as a contrast agent. HIF-1a conditional knockout mouse and/or NSPC-transplanted rat model will be used in these studies. Our proposed methods include stem cell isolation, expansion, differentiation and transplantation, direct contact and indirect in vitro cell co-cultures, immunofluorescence confocal microscopy, various biochemical and cell biology methods, HIF-1a gene silencing utilizing conditional knockout animals and shRNAi, as well as magnetic resonance imaging (MRI) using superparamagnetic nanoparticles (SPIOs).

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以出现在其他 CRISP 条目中 列出的机构是。 对于中心来说，它不一定是研究者的机构。 背景 利用神经干/祖细胞（NSPC）被认为是促进中风后大脑恢复的一种可能的治疗工具。我们的分子研究表明，NSPC 具有支持缺血后内皮细胞存活、形态发生和血管生成的强大能力。 NSPC 介导的保护机制使我们发现了一个重大发现，即 NSPC 的血管营养作用是通过激活 HIF-1a/VEGF 途径介导的。缺氧诱导因子 1 α 亚基 (HIF-1a) 是一种介导对缺氧的适应性细胞反应的转录激活剂，通常在大多数细胞类型和组织中降解，但在缺氧条件下，HIF-1a 会变得稳定并具有转录活性。发现 HIF-1a 在 NSPC 中持续表达，调节血管内皮生长因子 (VEGF) 的表达和促血管生成信号。我们的中心假设是神经干细胞为脑内皮细胞提供保护并支持缺血后脑血管系统的功能重塑我们认为 NSPC 的血管营养特性受转录因子 HIF-1 控制。 ，无论是在正常条件下还是缺氧后。 目标 为了解决我们的假设，我们建议研究 HIF-1 的作用¿ NSPC 功能中的信号传导并确定 NSPC 特异性 HIF-1 的影响¿我们的主要方法是使用磁共振成像 (MRI) 和超顺磁性纳米粒子 (SPIO) 作为对比剂来研究实验性局灶性缺血后脑血管系统的功能变化。 /或NSPC移植的大鼠模型将用于这些研究中，我们提出的方法包括干细胞分离、扩增、分化和移植、直接接触和间接体外细胞共培养，免疫荧光共聚焦显微镜、各种生化和细胞生物学方法、利用条件敲除动物和 shRNAi 的 HIF-1a 基因沉默，以及使用超顺磁性纳米颗粒 (SPIO) 的磁共振成像 (MRI)。