Endothelial Cell to Mesenchymal Cell Transitions Play a Critical Biological Sex- and Aging-Dependent Role in Formation and Maintenance of the Acta2+ Atherosclerotic Lesion Protective Fibrous Cap

内皮细胞向间充质细胞的转变在 Acta2 动脉粥样硬化病变保护性纤维帽的形成和维持中发挥着关键的生物性别和衰老依赖性作用

• 批准号: 10355596
• 负责人: Gary K Owens
• 金额: $ 79.29万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10355596
• 关键词: Aging; Antibodies; Apolipoprotein E; Apoptosis; Arterial Fatty Streak; Arteries; Atherosclerosis; Biological Assay; Bone Marrow Transplantation; Cardiovascular Diseases; Carotid Endarterectomy; Cause of Death; Cell Aging; Cell Lineage; Cell Proliferation; Cells; Clinical; Clinical Research; Clonal Expansion; Coronary artery; Coronary heart disease; Cytoskeleton; DNA biosynthesis; Deoxyuridine; Dependence; Development; Diet; Endothelial Cells; Event; Excision; Exhibits; Extracellular Matrix; Failure; Female; Functional disorder; Genes; Goals; Growth; Human; IL1R1 gene; Impairment; Incidence; Individual; Inflammation; Inflammatory; Intervention; Investments; Knock-out; Knockout Mice; Label; Lead; Lesion; Lesion by Stage; Life Style Modification; Lipids; Maintenance; Mechanics; Medicine; Mesenchymal; Metabolism; Modeling; Morphology; Mus; Myocardial Infarction; Myofibroblast; Nature; Oligonucleotides; PECAM1 gene; Paper; Pathogenesis; Permeability; Pharmaceutical Preparations; Phenotype; Platelet-Derived Growth Factor Receptor; Play; Predisposition; Probability; Process; Property; Relaxation; Research; Resistance; Role; Rupture; Sampling; Signal Transduction; Smooth Muscle Myocytes; Stroke; Testing; Thick; Thinness; Thrombosis; Time; United States; Woman; atherothrombosis; biological sex; cell type; conditional knockout; endothelial dysfunction; feeding; high risk; improved; in vivo; indexing; insight; irradiation; macrophage; male; men; novel; novel therapeutic intervention; prevent; senescence; sex; thrombotic; validation studies; western diet

Atherothrombosis, resulting from rupture or erosion of unstable atherosclerotic plaques, is the leading cause of death worldwide. However, the mechanisms that regulate the stability of late stage atherosclerotic lesions remain poorly understood. Recent studies from our lab (2021 Nature Metabolism) showed that smooth muscle cell (SMC) conditional knockout (KO) of the platelet-derived growth factor receptor- (PDGFR) in ApoE-/- mice was associated with nearly complete failure of SMC to invest into lesions or the fibrous cap. However, despite nearly complete absence of SMC in lesions of SMC PDGFR KO mice, surprisingly we observed no changes in lesion size or indices of plaque stability, including the thickness of the ACTA2+ fibrous cap, following 18 weeks of Western diet (WD). Further studies showed that: 1) contrary to dogma that Acta2+ fibrous cap cells are derived almost exclusively from SMC, we found they account for only 60-75% of ACTA2+ cells in advanced ApoE-/- brachiocephalic (BCA) or human coronary artery (CA) lesions with the remainder coming from endothelial cell (EC)-to-mesenchymal-to-myofibroblast transitions (EndoMT-MFT, 15-20%) and macrophage-to-myofibroblast transitions (MMFT, 10-15%); 2) loss of SMC investment into lesions with SMC PDGFR KO or bone marrow transplantation (BMT) was associated with a 2-3 fold increase in EndoMT-MFT and MMFT; 3) increased EndoMT-MFT, and MMFT did not sustain indices of stability when WD feeding was extended to 26 weeks suggesting qualitative differences in the ability of fibrous cap cells to sustain lesion stability depending on their origin; 4) the contribution of EC to the ACTA2+ fibrous cap increased with lesion regression by feeding mice 18 weeks of WD followed by 12 weeks of chow diet; and 5) female but not male mice exhibit IL1R1-dependent EndoMT. Studies herein will test the hypothesis that the contribution of EC to the ACTA2+ fibrous cap increases with lethal irradiation-BMT, SMC PDGFR KO, aging, female sex, and/or plaque regression resulting in: 1) increased EC proliferation and replicative senescence; 2) loss of EC integrity and/or reduced anti- thrombotic properties; and 3) increased susceptibility to plaque erosion or rupture. Aim 1 will determine if the marked increase in the contribution of EndoMT-MFT to the ACTA2+ fibrous cap following lethal irradiation-BMT, SMC PDGFR KO, or with plaque regression is associated with increased proliferation, clonal expansion, replicative senescence, and/or dysfunction of EC. Aim 2 will determine if treatment of our SMC- or EC-lineage tracing ApoE-/- or our novel Myh11-CreERT2/Rosa-eYFP/SR-BICT/CT/LDLR- (CT) mice with advanced BCA and CA lesions with senolytic drugs is associated with beneficial changes in indices of plaque stability, improved survival, reduced MI or stroke, reduced dependence on EndoMT-MFT for maintenance of the ACTA2+ fibrous cap, and/or improved EC integrity and/or function. All aims include human validation studies on stable versus high risk carotid endarterectomy samples, and assessment of sex-dependent determinants of late-stage lesion pathogenesis. The proposed studies will provide novel insights regarding mechanisms that regulate the cellular and extracellular matrix (ECM) composition of the fibrous cap and may lead to development of novel therapeutic approaches for enhancing plaque stability.

动脉粥样硬化血栓形成是由不稳定的动脉粥样硬化斑块破裂或侵蚀引起的，是导致动脉粥样硬化的主要原因。 然而，调节晚期动脉粥样硬化病变稳定性的机制仍然存在。 我们实验室的最新研究（2021 Nature Metabolism）表明平滑肌细胞（SMC） ApoE-/- 小鼠中血小板衍生生长因子受体- (PDGFR) 的条件敲除 (KO) 与 SMC 几乎完全无法进入病变或纤维帽，但是，尽管几乎完全失败。 SMC PDGFR KO 小鼠的病变中缺乏 SMC，令人惊讶的是我们没有观察到病变大小或指数的变化 西式饮食 (WD) 18 周后，斑块稳定性的变化，包括 ACTA2+ 纤维帽的厚度。 进一步的研究表明：1）与 Acta2+ 纤维帽细胞几乎完全源自的教条相反 SMC，我们发现它们仅占晚期 ApoE-/- 头臂 (BCA) 或人类 ACTA2+ 细胞的 60-75% 冠状动脉（CA）病变，其余部分来自内皮细胞（EC）到间充质到肌成纤维细胞 转变（EndoMT-MFT，15-20%）和巨噬细胞向肌成纤维细胞转变（MMFT，10-15%）；2) SMC 损失； 对 SMC PDGFR KO 或骨髓移植 (BMT) 病变的投资与 2-3 倍相关 EndoMT-MFT 和 MMFT 增加；3) EndoMT-MFT 增加，并且 MMFT 没有维持稳定性指数 WD 喂养延长至 26 周，表明纤维帽细胞维持能力的质量差异 病变稳定性取决于其来源；4) EC 对 ACTA2+ 纤维帽的贡献随着病变的增加而增加 通过给小鼠喂食 18 周的 WD，然后喂食 12 周的食物来恢复；5) 雌性小鼠而非雄性小鼠； 本文的研究将检验 EC 对 ACTA2+ 的贡献这一假设。 纤维帽随着致死性照射-BMT、SMC PDGFR KO、衰老、女性和/或斑块消退而增加 导致：1) EC增殖和复制衰老增加；2) EC完整性丧失和/或抗-能力降低 血栓形成特性；以及 3) 斑块侵蚀或破裂的易感性增加 目标 1 将决定是否显着。 致命照射-BMT、SMC 后 EndoMT-MFT 对 ACTA2+ 纤维帽的贡献增加 PDGFR KO 或斑块消退与增殖、克隆扩张、复制增加相关 目标 2 的衰老和/或功能障碍将决定是否治疗我们的 SMC 或 EC 谱系追踪 ApoE-/- 或我们的新型 Myh11-CreERT2/Rosa-eYFP/SR-BICT/CT/LDLR- (CT) 小鼠，患有晚期 BCA 和 CA 病变 senolytic 药物与斑块稳定性指数的有益变化、改善生存、减少 MI 或 中风，减少对 EndoMT-MFT 维持 ACTA2+ 纤维帽的依赖，和/或改善 EC 所有目标包括对稳定与高风险颈动脉内膜切除术的人体验证研究。 样本，以及晚期病变发病机制的性别依赖性决定因素的评估。 将提供有关调节细胞和细胞外基质（ECM）组成的机制的新见解 纤维帽的结构，并可能导致开发增强斑块稳定性的新治疗方法。