Novel Role of Thrombospondin-1 in Protection against Rupture of Abdominal Aortic Aneurysm

Thrombospondin-1 在预防腹主动脉瘤破裂中的新作用

• 批准号: 10609876
• 负责人: Bo Liu
• 金额: $ 45.99万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10609876
• 关键词: Abdominal Aortic Aneurysm; Actins; Address; Adoptive Transfer; Affect; Aneurysm; Angiotensin II; Animals; Aorta; Aortic Aneurysm; Aortic Rupture; Apoptotic; Area; Atherosclerosis; Blood Vessels; Bone Marrow; Breeding; CD47 gene; Cells; Clinical; Complication; Coupled; Data; Deoxyribonuclease I; Detection; Development; Dilatation - action; Elastases; Female; Gene Deletion; Growth; Human; Imipramine; Immunohistochemistry; Impairment; In Situ Hybridization; Incidence; Infiltration; Inflammation; Infusion procedures; Knock-out; Knockout Mice; Knowledge; Life Style; Low-Density Lipoproteins; LoxP-flanked allele; Macrophage; Mediating; Modeling; Molecular; Molecular Profiling; Monitor; Mouse Strains; Mus; Operative Surgical Procedures; Patients; Phagocytosis; Phenotype; Play; Polymers; Preventive; Proteins; Publications; Reporting; Research; Role; Rupture; Ruptured Abdominal Aortic Aneurysm; Ruptured Aneurysm; Small Interfering RNA; Source; System; THBS1 gene; Telemetry; Testing; Thrombospondin 1; Tissues; United States; Vascular Diseases; atherosclerotic plaque rupture; beta Aminopropionitrile; conditional knockout; extracellular; human disease; hypercholesterolemia; induced pluripotent stem cell; inhibitor; knock-down; male; migration; mortality; mouse model; neutrophil; novel; polymerization; receptor; response; single-cell RNA sequencing; spatial relationship; therapeutic development; ultrasound; uptake

Abdominal aortic aneurysm (AAA) is the progressive weakening and dilation of the aorta. A substantial knowledge gap exists in the understanding of molecular mechanisms responsible for aneurysm rupture, the major cause of mortality among AAA patients. Following our prior report of elevated thrombospondin-1 (TSP1) in human and mouse aneurysmal tissues, we conducted single-cell RNA sequencing (scRNA-seq) analysis and identified macrophages (Mɸs) being the primary source of elevated TSP1 in mouse aneurysmal aorta. We subsequently generated Mɸ-specific Thbs1 knockout mice (Thbs1∆Mɸ) by crossing Lyz2-Cre with our newly constructed Thbs1flox/flox mice. When subjected to aneurysm induction by angiotensin II (Ang II) coupled with hypercholesterolemia, over 60% of Thbs1∆Mɸ died due to AAA rupture, an incidence that was 2.6 times higher than Thbs1wt. Intriguingly, Thbs1∆Mɸ mice that survived to the end of 28-day Ang II infusion showed less aneurysm dilation than Thbs1wt. Smaller aneurysmal expansion was also found when Thbs1∆Mɸ mice were challenged with perivascular application of CaCl2, an AAA model that does not produce rupture. We propose two specific aims to delineate the mechanisms through which Mɸ-specific Thbs1 gene deletion differentially affects aortic dilation and rupture with an emphasis on AAA rupture. Specific Aim 1 devotes to establishing the rupture- preventive function of Mɸ TSP1. Specifically, we will determine the aortic responses proceeding lethal rupture in male and female Thbs1∆Mɸ mice in the Ang II model followed by identifying rupture-associated molecular signatures through scRNA-seq, in situ hybridization and immunostaining. Furthermore, we will examine the effects of Mɸ-specific Thbs1 knockout using a different murine model that produces rupture in advanced stages of aneurysm, which is more relevant to human AAA than the early rupture produced by the Ang II model. Specific Aim 2 focuses on investigating molecular mechanisms of aneurysm rupture. Preliminary studies showed that compared to wildtype, Thbs1-/- Mɸs had significantly reduced ability to migrate or to engulf apoptotic cells as well as neutrophil extracellular traps (NETs). We will test whether Mɸ TSP1 promotes NET clearance through CD47- mediated actin polymerization. Next, we will establish the causal effect of impaired Mɸ migration and phagocytosis on aneurysm rupture of Thbs1∆Mɸ mice. We will first determine whether NET burden is increased in Thbs1∆Mɸ died from rupture, and the spatial relationship between NETs and Mɸs. Second, we will test whether restoring Mɸ migration in Thbs1∆Mɸ reduces NET accumulation via adoptive transfer strategies. Furthermore, we will examine whether enhancing or attenuating NET clearance affect aneurysm rupture in Thbs1∆Mɸ. Lastly, we will analyze TSP1 expression and its association with Mɸ and NET accumulation in ruptured and non-ruptured human AAA tissues. By dissecting the multifaceted functions of Mɸs through TSP1 manipulations, this project will produce significant impact on the understanding of aneurysm rupture.

腹主动脉瘤（AAA）是主动脉的进行性弱化和扩张。大幅 在对动脉瘤破裂的分子机制的理解方面存在知识差距， 是AAA患者死亡的主要原因。根据我们先前关于血小板反应蛋白-1（TSP 1）升高的报告， 在人类和小鼠垂体组织中，我们进行了单细胞RNA测序（scRNA-seq）分析， 确定巨噬细胞（M β）是小鼠动脉瘤主动脉中升高的TSP 1的主要来源。我们 随后通过将Lyz 2-Cre与我们的新的Thbs 1基因敲除小鼠杂交， 构建Thbs 1flox/flox小鼠。当经受血管紧张素II（Ang II）与 在高胆固醇血症中，超过60%的Thbs 1 β M患者死于AAA破裂，发生率高2.6倍 Thbs1wt.有趣的是，Thbs 1 β M β小鼠存活到28天血管紧张素II输注结束时， 膨胀比Thbs 1 wt.当Thbs 1 β M β小鼠被激发时，也发现了较小的淋巴瘤扩张。 血管周围应用CaCl 2，AAA模型不产生破裂。我们提出两个具体目标 阐明M β特异性Thbs 1基因缺失差异影响主动脉粥样硬化的机制， 扩张和破裂，重点是AAA破裂。具体目标1致力于建立断裂- M β TSP 1的预防功能。具体地说，我们将确定致命性破裂前的主动脉反应， 雄性和雌性Thbs 1 β M β小鼠在Ang II模型中，随后鉴定破裂相关分子 通过scRNA-seq、原位杂交和免疫染色的特征。此外，我们将研究 使用不同的小鼠模型在晚期阶段产生破裂的M β特异性Thbs 1敲除的影响 的动脉瘤，这是更相关的人AAA比早期破裂产生的血管紧张素II模型。具体 目的2探讨动脉瘤破裂的分子机制。初步研究表明， 与野生型相比，Thbs 1-/- M β s迁移或吞噬凋亡细胞的能力也显著降低 中性粒细胞胞外陷阱（NETs）。我们将测试M β TSP 1是否通过CD 47促进NET清除， 介导的肌动蛋白聚合。接下来，我们将确定M迁移受损的因果影响， Thbs 1巨噬细胞吞噬作用对Thbs 1巨噬细胞吞噬作用的影响。我们将首先确定NET负担是否增加 Thbs 1组中，M细胞断裂死亡，NET与M细胞的空间分布关系。第二，我们将测试 通过过继转移策略，恢复Thbs 1-Thb M中的M迁移减少了NET积累。而且我们 将检查增强或减弱NET清除率是否会影响Thbs 1型颅内动脉瘤破裂。最后我们 将分析TSP 1的表达及其与破裂和非破裂组织中M β和NET积聚的相关性， 人AAA组织。通过剖析多方面的功能，M神经元通过TSP 1操纵，该项目 将对动脉瘤破裂的认识产生重大影响。

项目成果

Bim Expression Modulates Branching Morphogenesis of the Epithelium and Endothelium.

• DOI: 10.3390/biom12091295
• 发表时间: 2022-09-14
• 期刊: BIOMOLECULES
• 影响因子: 5.5
• 作者: Sorenson, Christine M.;Song, Yong-Seok;Wang, Shoujian;Darjatmoko, Soesiawati R.;Saghiri, Mohammad Ali;Ranji, Mahsa;Sheibani, Nader
• 通讯作者: Sheibani, Nader