Vascular signal as a therapeutic target for abdominal aortic aneurysm

血管信号作为腹主动脉瘤的治疗靶点

• 批准号: 8940888
• 负责人: SATORU EGUCHI
• 金额: $ 39万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8940888
• 关键词: 3' Untranslated Regions; Abdominal Aortic Aneurysm; Adenoviruses; Adult; Aldosterone; Angiotensin II; Animal Model; Animals; Aortic Aneurysm; Attenuated; BMX gene; Blood Vessels; Cardiovascular Diseases; Caveolae; Cell Culture Techniques; Cell model; Cells; Cultured Cells; DOCA; Data; Development; Disease; Elements; Epidermal Growth Factor Receptor; Event; Failure; Figs - dietary; GRP78 gene; Gene Proteins; Gene Silencing; Goals; Human; In Vitro; Intervention; Investigation; Knock-out; Knowledge; Link; Matrix Metalloproteinases; Mediating; Membrane Microdomains; Membrane Proteins; Metalloproteases; MicroRNAs; Mineralocorticoid Receptor; Modeling; Molecular; Molecular Chaperones; Mus; Oxidative Stress; Pathway interactions; Pharmacological Treatment; Phosphorylation; Prevention; Protein Tyrosine Kinase; Protein-Lysine 6-Oxidase; Proteins; Receptor Activation; Receptor Signaling; Renin-Angiotensin-Aldosterone System; Reporting; Risk Factors; Role; Rupture; Ruptured Abdominal Aortic Aneurysm; Signal Transduction; Signal Transduction Pathway; Signaling Molecule; Small Interfering RNA; Smooth Muscle Myocytes; Sodium Chloride; Stress; Structural Protein; System; Testing; Transactivation; Vascular remodeling; abdominal aorta; aged; caveolin 1; design; effective therapy; feeding; in vivo; inhibitor/antagonist; mortality; mouse model; novel; prevent; promoter; public health relevance; receptor; therapeutic target

 DESCRIPTION (provided by applicant): Abdominal aortic aneurysm (AAA) is a significant cause of mortality for adults aged >60 years. No established pharmacological treatment is currently available to prevent AAA advancement and/or rupture. Accumulating evidence suggests critical roles for the renin angiotensin aldosterone system (RAAS) in AAA formation. While several downstream signals and target proteins of AT1 receptor have been identified, there is a huge void in our knowledge regarding the proximal signaling events primarily responsible for AAA. Unfortunately, efficacies of the AngII blockers for human AAA appear to be limited. It is likely that the critical AAA promoting signal inducible upon AT1 stimulation is shard by many other AAA-promoting risk factors, such as by aldosterone (Aldo), indicating that an AngII blocker alone is insufficient as a treatment. Thus, we propose to determine alternative therapeutic targets for AAA in the AngII signal transduction pathway shared with other risk factors. We recently reported that caveolae membrane microdomains in vascular smooth muscle cells (VSMC) mediate a metalloprotease ADAM17-dependent EGFR transactivation, which is linked to vascular remodeling induced by AngII. Our preliminary data showed complete failure of AngII to induce AAA in mice lacking VSMC ADAM17 suggesting that ADAM17 is a potential target to prevent AAA. EGFR activation, ER stress and oxidative stress associated with AAA formation were also attenuated in VSMC ADAM17 deficient mice. Moreover, loss or inhibition of ADAM17 associated signaling elements (knockout of the caveolae structural protein, caveolin-1 or treatment with EGFR inhibitor) prevented AngII-dependent AAA as well as ER/oxidative stress. Enhanced ADAM17 expression and EGFR activation were also confirmed in human AAA. While EGFR transactivation appears critical for Aldo/mineralocorticoid receptor (MR) signal transduction in VSMC, whether the VSMC caveolae ADAM17/EGFR axis is critical for Aldo-mediated AAA is unclear. Here, we have developed the following 2 Aims to answer our key hypotheses. Aim 1. To investigate the contribution and mechanism of VSMC ADAM17 and EGFR in AAA. Hypothesis: VSMC ADAM17 is essential for AAA development and/or rupture through induction of ER stress and subsequent AAA associated genes/proteins via the novel feed forward loop of ADAM17/EGFR activation. Aim 2. To investigate the VSMC Cav1 mechanism and its consequence for the mouse models of AAA. Hypothesis: VSMC Cav1 silencing prevents ER stress and subsequent AAA formation and/or rupture through prevention of vascular ADAM17 activation by BMX. To accomplish these 2 Aims, 3 different AAA models will be used with mice lacking VSMC ADAM17, EGFR or Cav1. For an AngII- or Aldo-dependent AAA model, the mice will be infused with AngII plus BAPN, a lysyl oxidase inhibitor or treated with DOCA salt plus BAPN, respectively. For a RAAS-independent AAA model, the mouse abdominal aorta will be treated with CaCl2 plus PBS. In addition, this RAAS-independent AAA model and cultured VSMC will be used together with adenovirus encoding miRNA-embedded siRNA targeting ADAM17, EGFR, Cav1 or BMX. Accomplishment of this proposal will explore the novel feed-forward loop mechanism initiated by vascular caveolae compartmentalized signaling molecules as a potential therapeutic target for reducing AAA development.

 描述（适用提供）：腹主动脉瘤（AAA）是年龄> 60岁的成年人死亡的重要原因。目前尚无既定药物治疗可防止AAA的进步和/或破裂。积累的证据表明，肾素血管紧张素醛固酮系统（RAAS）在AAA形成中的关键作用。尽管已经确定了AT1受体的几个下游信号和靶蛋白，但我们的知识中，关于主要负责AAA的近端信号事件存在巨大的空白。不幸的是，人类AAA的Angii阻滞剂的效率似乎有限。许多其他促进AAA的危险因素（例如Aldosterone（Aldo））可能会降低AT1刺激时的关键AAA启动子信号，这表明单独使用Angii阻滞剂作为治疗不足。这，我们建议确定与其他风险因素共享的ANGII信号转导途径中AAA的替代治疗靶标。我们最近报道说，血管平滑肌细胞（VSMC）中的小窝膜微域介导金属蛋白酶ADAM17依赖性EGFR反式激活，这与Angii诱导的血管重塑有关。我们的初步数据表明，AngII完全失败了缺乏VSMC ADAM17的小鼠诱导AAA，这表明ADAM17是预防AAA的潜在目标。在VSMC ADAM17特异性小鼠中，EGFR激活，与AAA形成相关的EGFR激活，与AAA形成相关的氧化应激也被衰减。此外，ADAM17相关的信号传导元件的丢失或抑制作用（可口可测结构蛋白，可爱素-1或用EGFR抑制剂处理）阻止了Angii依赖性AAA以及ER/氧化应激。在人AAA中也证实了增强的ADAM17表达和EGFR激活。虽然EGFR反式激活对于VSMC中的Aldo/矿物皮质激素受体（MR）信号转导至关重要，但VSMC Caveolae ADAM17/EGFR轴是否对于Aldo介导的AAA至关重要。在这里，我们开发了以下两个旨在回答我们的关键假设的目标。目的1。研究AAA中VSMC ADAM17和EGFR的贡献和机制。假设：VSMC ADAM17通过ADAM17/EGFR激活的新型Feed Forward回路，通过诱导ER应力和随后的AAA相关基因/蛋白质而对AAA发育和/或破裂至关重要。目标2。研究VSMC CAV1机制及其对AAA小鼠模型的影响。假设：VSMC CAV1沉默可以通过预防BMX的血管ADAM17激活来阻止ER应力和随后的AAA形成和/或破裂。为了实现这两个目标，将使用3种不同的AAA模型，而缺乏VSMC ADAM17，EGFR或CAV1的小鼠。对于Angii或Aldo依赖性AAA模型，小鼠将分别感染Angii Plus BAPN，一种赖氨酸氧化物抑制剂或用DOCA盐和BAPN处理的小鼠。对于不依赖RAAS的AAA模型，将用CACL2加PBS处理小鼠腹主动脉。此外，这种独立于RAAS的AAA模型和培养的VSMC将与编码miRNA嵌入的siRNA靶向ADAM17，EGFR，CAV1或BMX一起使用。该提案的完成将探讨由血管caveolae隔室信号分子引发的新型馈送回路机制，作为减少AAA发育的潜在治疗靶标。