Alpha5Beta1 Integrin inhibition as a Profound Blood-Brain Barrier Stabilizing Neuroprotective Stroke Therapy

 描述（由申请人提供）：虽然中风是美国第四大死亡原因，对于大多数由于血凝块（缺血性）引起的中风，目前的溶栓治疗策略具有混合的结果。因此，迫切需要新的和更好的中风疗法。我们之前已经证明，脑细胞外基质成分串珠素的结构域V蛋白片段通过与脑内皮细胞受体α5β1整联蛋白的相互作用，在缺血性中风后具有神经保护作用和神经修复作用。有趣的是，初步结果表明，内皮细胞选择性缺失α5β1整合素的小鼠， 对实验性缺血性中风有很强的抵抗力;它们几乎没有脑损伤的迹象。此外，用ATN-161或其更有效的同种型Ac-PhScN-NH 2抑制α5β1整联蛋白在野生型小鼠中传递几乎相同的对中风损伤的抗性。这可以通过增加脑内皮细胞紧密连接蛋白claudin-5的功能来稳定血脑屏障，从而使血管源性水肿、炎症和损伤最小化。因此，我们假设内皮细胞α5β1整合素可能是卒中的一个特别有效的治疗靶点。在本申请中，我们提出了以下具体目标：1。确定内皮细胞选择性α5β1整合素缺失对实验性缺血性脑卒中的影响。确定α5β1整合素作为实验性缺血性卒中治疗靶点的潜力;确定α5β1整合素在调节血脑屏障完整性和随后抵抗缺血性卒中中的作用的详细机制。我们将在实验性卒中模型和体外内皮细胞屏障试验中使用几种新型遗传修饰小鼠（α5整联蛋白内皮细胞特异性敲除小鼠、claudin 5 eGFP标记小鼠）和新表征的α5β1整联蛋白抑制剂。我们希望证明，抑制或抑制内皮细胞中的α5β1整合素可提供显著的血脑屏障介导的对实验性缺血性卒中的抵抗，支持我们开发α5β1整合素作为新的人类卒中治疗靶点的长期目标。

 DESCRIPTION (provided by applicant): Although stroke is the fourth leading cause of death in the U.S., the current treatment strategy of thrombolysis for the majority of strokes due to a blood clot (ischemic) has mixed results. Thus, there is an urgent need for new and better stroke therapies. We have previously demonstrated that the domain V protein fragment of the brain extracellular matrix component perlecan is both neuroprotective and neuroreparative after ischemic stroke by interaction with the brain endothelial cell receptor α5β1 integrin. Intriguingy, preliminary results now suggest that mice with an endothelial selective deletion of α5β1 integrin are profoundly resistant to experimental ischemic stroke; they show little to no signs of brain injury. Furthermore, inhibition of the α5β1 integrin with ATN-161 or its more potent isoform Ac-PhScN-NH2 conveys nearly identical resistance to stroke injury in wild type mice. This may occur via stabilization of the blood-brain barrier through increased function of the brain endothelial cell tight junction protein claudin-5, which in turn minimizes vasogenic edema, inflammation, and injury. Therefore, we hypothesize that endothelial cell α5β1 integrin could be a particularly effective therapeutic target for stroke. In this application, we propose the followig specific aims: 1. Determine the effect of endothelial cell selective α5β1 integrin deletion on experimental ischemic stroke, 2. Determine the potential of the α5β1 integrin as a therapeutic target in experimental ischemic stroke and 3. Determine, in mechanistic detail, the role of α5β1 integrin in modulating blood-brain barrier integrity and subsequent resistance to ischemic stroke. We will use several novel genetically modified mice (α5 integrin endothelial cell specific knockdown mice, claudin5 eGFP tagged mice) and newly characterized α5β1 integrin inhibitors in experimental stroke models and in vitro endothelial cell barrier assays. We expect to demonstrate that suppression or inhibition of α5β1 integrin in endothelial cells affords significnt blood-brain barrier-mediated resistance to experimental ischemic stroke, supporting our long-term goal of developing α5β1 integrin as a novel human stroke therapeutic target.