MICROGLIA ACTIVATION IN RESPONSE TO BLOOD-BRAIN BARRIER DISRUPTION IN THE CNS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 血脑屏障（BBB）破坏是与血管渗透性和血蛋白渗漏到CNS中相关的神经系统疾病的标志，例如中风、多发性硬化（MS）、阿尔茨海默病（AD）、脑梗死和脑梗死。s疾病（AD）、脑胶质母细胞瘤和脊髓损伤。尽管血管异常和持续性BBB破坏代表MS中脱髓鞘病变和AD和卒中中神经变性区域的早期组织病理学改变之一，但血管通透性如何损害脑功能的分子基础在很大程度上仍然未知。我们先前的研究确定了血因子，当血脑屏障破坏后沉积在神经系统中时，它们抑制周围神经再生并加剧MS动物模型中中枢神经系统的炎性脱髓鞘。该提议中的具体假设是，血脑屏障破坏导致CNS中的血液渗漏是小胶质细胞活化的原因。我们的假设是基于以下观察：1。使用双光子显微镜，小胶质细胞通过过程延伸和创伤部位的隔离对脑中血管损伤做出非常迅速的反应; 2.小胶质细胞可以在体外响应血液因子而被激活，导致肌动蛋白细胞骨架的动态重排、膜皱褶和吞噬作用增加。基于这些观察结果，本提案的实验重点是在小鼠脑中使用实时成像通过BBB破坏和血液渗漏直接证明小胶质细胞活化。由于已经阐明了响应血液因子的小胶质细胞活化的几种分子途径，我们计划通过药理学和遗传操作结合我们的体内成像方法来测试这些途径的参与。通过这样做，我们希望我们的工作提供血液因子和脑实质之间的分子联系的最先进的示范，因为它涉及到胶质细胞活化，几个脑血管和神经退行性病变的标志。

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. Blood-brain barrier (BBB) disruption is a hallmark of nervous system diseases associated with vascular permeability and leakage of blood proteins into the CNS, such as stroke, multiple sclerosis (MS), Alzheimers Disease (AD), brain glioblastomas and spinal cord injury. Even though vascular abnormalities and persistent BBB disruption represent one of the early histopathological alterations of demyelinating lesions in MS and areas of neurodegeneration in AD and stroke, the molecular basis of how vascular permeability impairs brain function remains largely unknown. Our previous studies identified blood factors that when deposited in the nervous system after BBB disruption, they inhibit peripheral nerve regeneration and exacerbate inflammatory demyelination in the central nervous system in an animal model for MS. The specific hypothesis in this proposal is that BBB disruption that leads to leakage of blood in the CNS is responsible for microglia activation. Our hypothesis is based on the observations that: 1. Using two-photon microscopy, microglia respond very rapidly by process extension and isolation of the traumatized sites to blood vessel damage in the brain; 2. Microglia can get activated in vitro in response to blood factors, resulting in a dynamic rearrangement of the actin cytoskeleton, membrane ruffling, and increased phagocytosis. Based on these observations, the experimental focus of this proposal is on the direct demonstration of microglial activation by BBB disruption and blood leakage using live imaging in the mouse brain. Since several molecular pathways of microglial activation in response to blood factors have being elucidated, we plan to test the involvement of these pathways by pharmacologic and genetic manipulations in combination to our in vivo imaging approach. By doing so, we expect our work to provide a state-of-the-art demonstration of the molecular link between blood factors and brain parenchyma as it relates to glial cell activation, a hallmark of several cerebrovascular and neurodegenerative pathologies.