EGR-1 Mediated Revascularization and Arteriogenic Bypass

EGR-1介导的血运重建和动脉搭桥

• 批准号: 8212009
• 负责人: Todd K Rosengart
• 金额: $ 38.86万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8212009
• 关键词: Acute; Address; Adenoviruses; Anatomy; Animals; Area; Arterial Fatty Streak; Binding; Biological; Biological Assay; Biology; Blood Vessels; Blood capillaries; Brain Hypoxia-Ischemia; Bromodeoxyuridine; Bypass; CD44 gene; Cell Adhesion Molecules; Cells; Chronic; Clinical Data; Clinical Research; Clinical Trials; Coronary; Coronary heart disease; Coupling; Dependovirus; Development; Effectiveness; Electric Capacitance; Family suidae; Fibroblast Growth Factor 2; Gene Transfer; Generations; Genes; Growth; Growth Factor; Harvest; Health; Home environment; Hypoxia; In Vitro; Individual; Inflammation Mediators; Inflammatory; Intercellular adhesion molecule 1; Intervention; Ischemia; Knock-in Mouse; Knock-out; Knockout Mice; Label; LacZ Genes; Ligation; Limb structure; Mechanical Stress; Mediating; Mediator of activation protein; Modeling; Molecular; Monocyte Chemoattractant Protein-1; Myocardial Ischemia; Obstruction; Pathway interactions; Perfusion; Peripheral; Peripheral Vascular Diseases; Physiological; Platelet-Derived Growth Factor; Pneumonectomy; Prevention; Process; Rattus; Regulation; Relative (related person); Reperfusion Therapy; Role; Series; Signal Pathway; Signal Transduction; Site; Smooth Muscle Myocytes; Staining method; Stains; Stem cells; Stimulus; Stress; Testing; Therapeutic; Time; Tissues; Transfection; Transforming Growth Factors; Transgenes; Translating; Up-Regulation; Vascular Endothelial Cell; Vascular Endothelial Growth Factors; Vascularization; Wild Type Mouse; advanced disease; angiogenesis; arteriole; base; capillary; catalyst; cell type; conventional therapy; cytokine; gene transfer vector; in vivo; macrophage; migration; monocyte; mutant; neovascularization; neovasculature; new growth; pre-clinical; promoter; receptor; response; sensor; shear stress; therapeutic angiogenesis; transcription factor; tumor growth; vector

DESCRIPTION (provided by applicant): Arteriogenesis describes the process of collateral vessel growth that is thought to be a critical biologic response to vascular occlusion. While clinical trials employing the "therapeutic" administration of angiogenic growth factors have generally yielded disappointing results, it now appears that arteriogenesis may be more relevant than angiogenesis in creating a robust, large capacitance, stable neovasculature that can literally provide native "bypasses" of vascular obstructions. In this regard, while ischemia/hypoxia are likely the primary physiologic triggers of angiogenesis, monocyte recruitment in response to vascular shear and other stresses has been implicated as a key early mediator of arteriogenesis. The molecular basis of this activation pathway is unclear, however, and while the arbitrary administration of growth factors may deleteriously bypass "upstream" signaling pathways, an "arteriogenic" transcription factor has yet to be identified. The EGR-1 transcription factor is responsive to changes in shear stress independent of the presence of hypoxia, and can activate a portfolio of potentially arteriogenic growth factors and molecules. In this context, we became intrigued by our demonstration of the rapid upregulation of EGR-1 expression following vascular occlusion, the near- absence of monocyte recruitment and reperfusion following vascular ligation in EGR-1 null mice, and the near-normalization of perfusion following EGR-1 administration to ligated wild type animals. We consequently speculated that EGR-1 is the "missing" signal that transponds the physiologic sequelae of vascular occlusion into an (arteriogenic) neovascularization response. The current aims are therefore to test the hypotheses that EGR-1: 1) induces arteriogenesis as a critical response to vascular occlusion, by upregulation of key arteriogenic mediators, 2) induces monocyte recruitment as the catalyst for this response (and augment this process therapeutically), and 3) can "therapeutically" induce stable revascularization greater than that induced by "downstream" angiogenic mediators. To pursue these aims, we will use vascularization, perfusion and expression assays following vascular ligation in wild type vs. EGR-1 deficient (EGR-knockout or LacZ knock-in) mouse, rat and in a hypercholesterolemic swine myocardial ischemia models with or without VEGF, MCP-1 or EGR-1 administration, via acute or chronic (regulatable and tissue specific) gene transfer vectors. These studies should elucidate the microanatomic site and the locus in molecular signaling pathways of EGR-1 mediated regulation of revascularization, and provide pre-clinical data regarding the benefits of revascularization strategies via arteriogenic vs. angiogenic agents, and via a "master switch" transcription factor vs. downstream mediators. PUBLIC HEALTH RELEVANCE Despite ongoing advances in the prevention and treatment of coronary and peripheral vascular disease, it is estimated that advanced disease limits the effectiveness or applicability of conventional therapies in approximately 50,000 - 80,000 individuals in the U.S. alone, who can be expected to die annually from coronary disease, and approximately 100,000 individuals will suffer limb loss from peripheral vascular disease. Interventions that can alter vascular biology and enhance the body's own ability to bypass itself by growing collateral vessels (arteriogenesis) therefore represent attractive alternatives to conventional therapies. Based upon a growing number of lines of evidence, we believe that a gene called Egr-1 may be a "missing" signaling factor that can translate the physiologic (mechanical) stresses of vascular blockages into the growth of a stable and persistent new vasculature. This study seeks to elucidate the role of Egr-1 in native blood vessel growth and its potential use as a potent "arteriogenic" revascularization agent.

描述(申请人提供)：动脉生成描述侧支血管生长的过程，被认为是对血管闭塞的关键生物学反应。虽然临床试验使用血管生成生长因子的“治疗性”给药通常产生了令人失望的结果，但现在看来，动脉生成可能比血管生成在创造强大、大容量、稳定的新生血管方面更相关，这种新生血管实际上可以提供天然的“旁路”血管阻塞。在这一点上，虽然缺血/缺氧可能是血管生成的主要生理触发因素，但单核细胞对血管剪切和其他应激的反应已被认为是动脉生成的关键早期介质。然而，这一激活途径的分子基础尚不清楚，尽管随意给予生长因子可能有害地绕过“上游”信号通路，但“动脉生成”转录因子尚未确定。EGR-1转录因子对剪切力的变化反应独立于低氧的存在，并可以激活一系列潜在的动脉生成生长因子和分子。在此背景下，我们对血管闭塞后EGR-1的表达迅速上调，血管结扎后EGR-1缺失的小鼠几乎没有单核细胞募集和再灌注，以及在结扎的野生型动物给予EGR-1后灌流接近正常引起了我们的兴趣。因此，我们推测EGR-1是将血管闭塞的生理后遗症转化为(动脉生成的)新生血管反应的“缺失”信号。因此，目前的目标是验证以下假设：EGR-1：1)通过上调关键的动脉生成介质诱导动脉生成作为血管闭塞的关键反应，2)诱导单核细胞募集作为这一反应的催化剂(并在治疗上增强这一过程)，以及3)可以“治疗性地”诱导比“下游”血管生成介质诱导的稳定的血管再形成。为了实现这些目标，我们将通过急性或慢性(可调节的和组织特异性的)基因转移载体，在野生型和EGR-1缺陷(EGR-基因敲除或LacZ敲入)小鼠、大鼠和高胆固醇血症猪心肌缺血模型中，通过急性或慢性(可调节的和组织特异性的)基因转移载体，使用血管形成、灌流和表达分析。这些研究应阐明EGR-1介导的血管重建调控的分子信号通路中的微解剖位置和位置，并提供临床前数据，说明通过动脉生成因子和血管生成因子，以及通过“总开关”转录因子和下游介质进行血管重建策略的益处。公共卫生相关性尽管在预防和治疗冠状动脉和外周血管疾病方面不断取得进展，但据估计，仅在美国，晚期疾病就限制了传统疗法的有效性或适用性，预计每年约有5万至8万人死于冠状动脉疾病，约10万人将因外周血管疾病而失去肢体。因此，能够改变血管生物学并通过增加侧支血管(动脉生成)来增强身体自身绕过自身的能力的干预措施，是传统疗法的有吸引力的替代方案。根据越来越多的证据，我们认为一种名为Egr-1的基因可能是一种“缺失的”信号因子，可以将血管阻塞的生理(机械)压力转化为稳定和持久的新血管的生长。本研究试图阐明Egr-1在天然血管生长中的作用及其作为一种有效的“动脉源性”血管重建剂的潜在用途。