Protease-Mediated Vascular Instability in Development and Disease

项目摘要/摘要 血管完整性对于预防组织水肿、血栓形成、炎症和出血至关重要。 识别积极或消极影响血管完整性的新因素可以提供重要的 维持血管健康的治疗选择。在过去的十年里，我的实验室采用了公正的基因 在小鼠身上产生血管表型并识别其机制原因的方法，我们已经 从我们的工作中看到了一个强有力的主题：过度的蛋白质分解对血管内皮细胞和 体内血管的完整性。尽管蛋白水解酶被公认为调节新的萌芽血管生成 在血管方面，关于它们对已建立的血管内皮细胞的影响的认识仍然存在差距。 因此，NHLBI新兴研究员奖的目标是定义背景和 蛋白水解酶破坏血液和淋巴管完整性的机制。我们将着手解决这一问题 通过扩展两个研究领域来实现广泛的目标，这两个领域得到了我们已发表和初步数据的支持。 首先，我们将在蛋白酶介导的血管损伤的背景下检查细胞外基质的降解。 我们将利用我们的多种具有升高的蛋白酶活性的遗传模型来揭示基质中的共性 血管破裂部位附近的成分和碎片，我们将设法辨别亲属 基质支架与基质/内皮细胞信号在维持体内血管完整性中的重要性。 其次，我们将重点介绍蛋白水解酶介导的内皮细胞坏死性下垂。坏死性下垂是一种新发现的 细胞死亡的一种形式，对其在血管系统中的原因或影响知之甚少。我们的初步数据 提示在胚胎发育过程中，蛋白水解酶可以直接触发内皮细胞坏死性下垂。我们会 研究这种情况发生的机制，并将确定蛋白酶介导的作用。 坏死性上睑下垂可引起各种出生后血管疾病。拟议中的研究是范式转换，因为它 考虑蛋白水解酶在血管完整性方面的新作用，因为它可能产生新的 针对与高蛋白酶活性和血管脆弱性相关的病理疾病的治疗靶点。

PROJECT SUMMARY/ABSTRACT Vascular integrity is critical for the prevention of tissue edema, thrombosis, inflammation, and hemorrhage. Identifying new factors that influence vascular integrity positively or negatively can provide important therapeutic options for maintaining vascular health. Over the last decade, my lab has taken unbiased genetic approaches in mice to generate vascular phenotypes and to discern their mechanistic causes, and we have seen a powerful theme emerge from our work: excessive proteolysis is detrimental to endothelial cells and to vascular integrity in vivo. Although proteases are well recognized for regulating sprouting angiogenesis in new vessels, there is still a gap in knowledge about their impact on the endothelium of established vessels. Therefore, the objective of this NHLBI Emerging Investigator Award is to define the contexts and the mechanisms through which proteases damage blood and lymphatic vessel integrity. We will approach this broad objective by expanding on two research areas that are supported by our published and preliminary data. First, we will examine extracellular matrix degradation in the context of protease-mediated vascular damage. We will exploit our multiple genetic models with elevated protease activity to reveal commonalities in matrix composition and fragmentation near sites of vascular rupture, and we will seek to discern the relative importance of matrix scaffolding versus matrix/endothelial cell signaling in maintaining vascular integrity in vivo. Secondly, we will focus on protease-mediated endothelial cell necroptosis. Necroptosis is a newly-identified form of cell death, and little is known about its causes or effects in the vasculature. Our preliminary data indicate that proteases can directly trigger endothelial cell necroptosis during embryonic development. We will examine the mechanism through which this occurs and will determine the contribution of protease-mediated necroptosis to various postnatal vascular diseases. The proposed research is paradigm-shifting because it considers new roles for proteases in the context of vascular integrity and because it could generate new therapeutic targets for pathologies associated with high protease activity and vascular fragility.