CEREBRAL PROTECTION & RECOVERY AFTER CIRCULATORY ARREST

描述(由申请人提供)： 这是R01 NS/HL36124-06的竞争性更新，它支持了首席调查员实验室主要项目的发展和继续。研究人员开发并验证了大鼠心脏骤停和复苏的临床相关结局模型。该模型与最先进的磁共振成像(MRI)的使用完全兼容，以便(1)将长期神经元损伤与复苏后局部脑血流(RCBF)、离子/水平衡(表现为表观扩散系数(ADC)和脑能量代谢)的异常联系起来，(2)评估不同治疗策略在良好控制的循环停止后对脑保护和复苏的效果。过去四年的研究得出的结论是，如果不解决血管对全球缺血和复氧的反应，基于能量代谢和兴奋毒性机制的治疗将不可避免地失败。在接下来的五年里，研究人员将检验这一中心假设，即复苏后的血管内良好可以通过实质内干预恢复。这项研究将集中在两个密切相关的实质内事件：血管生成和神经生成。脑源性神经营养因子(BDNF)和血管内皮生长因子(VEGF)在减轻再灌注损伤中的可能作用将被研究。脑源性神经营养因子和血管内皮生长因子被选中是因为它们已被证实对缺血的神经保护作用，但它们在提供再灌注损伤和长期低灌流的实质内治疗方面的直接参与还没有被探索。它们对再灌注损伤的保护作用机制尚不完全清楚。这两个因素之间的协同联系是他们选择这个项目的基础，最近的研究发现，这两个因素似乎都通过细胞外信号相关蛋白激酶(ERK)途径发挥神经保护作用。研究人员已经开发出广泛的基因传递和转移到脑旁瘤的方法。拟议的新研究将结合使用重组腺相关病毒(RAAV)的基因治疗和STREN细胞治疗来实现以下三个特定目标：特定目标1：探讨BDNF广泛过表达对局部再灌注恢复和减少选择性易损区神经元丢失的治疗作用。具体目的#2：实现血管内皮生长因子主要剪接变异体(VEGF121和VEGF165)在大鼠脑内的广泛基因传递和过度表达，以帮助复苏后的血管生成对抗低灌流。具体目的#3：设计一种多能干细胞弥漫性脑移植的方法，并结合脑源性神经营养因子和血管内皮生长因子的基因治疗，研究血管生成和神经再生的相互作用。希望这些特定的研究将为最终确定全脑缺血复苏后血管生成和神经生成之间的因果相互作用铺平道路。

DESCRIPTION (provided by applicant): This is competitive renewal of R01NS/HL36124-06, which has supported the development and continuation of the primary project in the Principal Investigator's laboratory. The investigators have developed and validated a clinically relevant outcome model of cardiac arrest and resuscitation in rats. The model is fully compatible with the use of the state-of-the-art magnetic resonance imaging (MRI) in order to (1) correlate long-term neuronal damage with post-resuscitation abnormalities in regional cerebral blood flow (rCBF), ion/water homeostasis as manifested in apparent diffusion coefficient (ADC), and cerebral energy metabolism, and (2) to evaluate the efficacy of different treatment strategies for cerebral protection and resuscitation after a well-controlled circulatory arrest. Research in the past four years has led to the conclusion that treatment based on energy metabolism and excitotoxicity mechanisms will inevitably fail if the vascular response to global ischemia and re-oxygenation is not addressed. For the next five years, the investigators will test the central hypothesis that intravascular goodness after resuscitation can be restored by intraparenchymal interventions. The research will focus on two closely related intraparenchymal events: angiogenesis and neurogenesis. Possible roles of the brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) in alleviation of reperfusion injury wilt be investigated. BDNF and VEGF are chosen for their proven neuroprotective effects against ischerrfia, but their direct involvement in providing intraparenchymal treatment for reperfusion injury and protracted hypoperfusion has not been explored. The mechanisms of their protection against reperfusion injury are not fully understood. The synergistic link between these two factors, which underlies their choice for this project, is the recent finding that both factors seem to exert their neuroprotective effects via the extmcellular signal-related protein kinase (ERK) pathway. Methods for widespread gene delivery and transfer into the brain parenehyma have been developed by the investigators. The proposed new studies will combine gene therapy using recombinant adeno-associated viruses (rAAV) and stern cell therapy to accomplish the following three specific aims: Specific Aim #1: To investigate the therapeutic effects of the wide-spread over-expression of BDNF on the regional reperfusion recovery and reduction of neuronal loss in the selective vulnerability regions. Specific Aim #2: To achieve wide-spread gene delivery and over-expression of the main splice variants of VEGF (VEGF121 and VEGF165) in the rat brain to assist the post-resuscitation angiogenesis against hypoperfusion. Specific Aim #3: To devise a method for diffusive cerebral transplantation of multipotent stem cells and, in combination with BDNF and VEGF gene therapy, to study interaction of angiogenesis and neurogenesis. It is hoped that these specific investigations wilt pave the way to ultimately identifying the causal interaction between angiogenesis and neurogenesis after resuscitation from global ischemia.