LncRNA MAARS, macrophage apoptosis, and atherosclerosis

LncRNA MAARS、巨噬细胞凋亡和动脉粥样硬化

基本信息

批准号：
10214694
负责人：
MARK W FEINBERG
金额：
$ 41.59万
依托单位：
BRIGHAM AND WOMEN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-15 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10214694
关键词：
Address Affect Apoptosis Apoptosis Regulation Gene Apoptotic Arterial Fatty Streak Atherosclerosis Attention Biological Assay Biological Process Biophysics Bone Marrow CASP3 gene Carotid Artery Diseases Cause of Death Cell Death Cell physiology Cells Characteristics Chromatin Remodeling Factor Chronic Cleaved cell Code Data Deletion Mutation Dependence Detection Disease Disease Progression Event Foundations Genes Goals Homologous Gene Human In Vitro Kinetics Knockout Mice Lesion Link Lipids Longitudinal Studies Mediating Molecular Mus Myocardial Infarction Necrosis Nuclear Peripheral Blood Mononuclear Cell Peripheral Vascular Diseases Phase Play Poly A Process Proteins RNA RNA Sequences RNA-Binding Proteins Regulation Role Signal Pathway Signal Transduction Splenocyte Stains Stimulus Stroke Therapeutic Untranslated RNA Vascular Diseases Work atherogenesis base genetic signature improved in vivo inhibitor/antagonist insight knock-down mRNA Stability macrophage new therapeutic target novel novel therapeutic intervention trafficking transcriptome sequencing

项目摘要

Atherosclerosis, a chronic arterial disease, involves multiple cellular processes including the accumulation of intimal macrophages. Macrophage apoptosis is increased with progression of atherosclerosis, leading to increased cell death and accumulation of cellular debris. This in turn may abrogate macrophage efferocytosis, an important event for clearance of apoptotic or necrotic cells. Therefore, improving the efficiency of macrophages in the clearance of intra-lesional cellular debris may provide a novel therapeutic approach to limit atherosclerotic progression. Long non-coding RNAs (lncRNAs) have garnered widespread attention as emerging regulators of diverse biological processes relevant to atherosclerosis. However, the identity and roles of specific lncRNAs within atherosclerotic lesions are not well defined. Using RNA-Seq profiling to identify lncRNAs derived specifically from the aortic intima of LDLR-/- mice during lesion progression and regression phases, we identify the lncRNA MAARS (Macrophage-Associated Atherosclerosis lncRNA Sequence). MAARS was the highest expressed lncRNA with a 300-fold increase after lesion progression and decreased by 70% with regression. MAARS is a polyadenylated, macrophage- and nuclear-specific, lncRNA. Kinetic studies showed that MAARS expression is markedly induced in macrophages differentiated from bone marrow, PBMCs, or splenocytes. Our preliminary data demonstrate that systemic delivery of inhibitors to MAARS strongly reduced lesion size, independent of effects on circulating lipid profile, but rather by decreased macrophage apoptosis and increased efferocytosis in the vessel wall. Deficiency of MAARS reduced macrophage apoptosis induced by different stimuli and increased macrophage efferocytosis in vitro. Mechanistically, lncRNA pulldown assays in combination with LC-MS/MS analysis showed that MAARS interacts with HuR, an RNA-binding protein and important regulator of apoptosis. Preliminary studies show that HuR silencing increases macrophage apoptosis and that the MAARS-mediated effects on macrophage apoptosis may be HuR dependent. In addition, MAARS knockdown altered HuR nuclear-cytoplasmic trafficking, and regulated important apoptotic genes. These observations provide the foundation for the central hypothesis that MAARS deficiency, via regulatory effects on HuR and specific macrophage apoptotic signaling pathways, reduces macrophage apoptosis, improves cellular efferocytosis, and suppresses atherosclerosis. To address this further, in Aim1 we examine the role of MAARS in regulating HuR-mediated macrophage apoptosis and efferocytosis; in Aim2, we assess how alterations of MAARS expression affects short- and long-term atherosclerosis in vivo; and in Aim3, we examine the role of the MAARS-HuR signaling axis in human cells and atherosclerotic lesions. Our studies will address a major gap in our understanding of lncRNAs in atherosclerosis and inform how MAARS-mediated control of macrophage apoptosis and efferocytosis may provide new targets for therapy.

动脉粥样硬化是一种慢性动脉疾病，涉及多种细胞过程，包括内膜巨噬细胞。巨噬细胞凋亡随着动脉粥样硬化的进展而增加，导致细胞死亡增加和细胞碎片积累。这反过来可能会消除巨噬细胞的胞吞作用，清除凋亡或坏死细胞的重要事件。因此，提高效率巨噬细胞清除病灶内细胞碎片可能提供一种新的治疗方法来限制动脉粥样硬化进展。长链非编码RNA（lncRNA）作为新兴的调控因子而受到广泛关注。与动脉粥样硬化相关的多种生物过程。然而，特定lncRNA的身份和作用动脉粥样硬化病变内部尚不明确。使用 RNA-Seq 分析来鉴定衍生的 lncRNA 特别是从 LDLR-/- 小鼠在病变进展和消退阶段的主动脉内膜中，我们确定 lncRNA MAARS（巨噬细胞相关动脉粥样硬化 lncRNA 序列）。 MAARS 是最高的病变进展后，lncRNA 表达增加 300 倍，消退后表达减少 70%。 MAARS 是一种聚腺苷酸化、巨噬细胞和核特异性的 lncRNA。动力学研究表明 MAARS 在从骨髓、PBMC 或脾细胞分化的巨噬细胞中显着诱导表达。我们的初步数据表明，全身性递送 MAARS 抑制剂可大大减小病变大小，与对循环脂质谱的影响无关，而是通过减少巨噬细胞凋亡和血管壁胞吞作用增加。 MAARS 缺乏可减少巨噬细胞凋亡不同的刺激和体外巨噬细胞胞吞作用的增加。从机制上讲，lncRNA Pulldown 检测结合 LC-MS/MS 分析表明 MAARS 与 HuR（一种 RNA 结合蛋白）相互作用细胞凋亡的重要调节因子。初步研究表明HuR沉默会增加巨噬细胞凋亡 MAARS 介导的巨噬细胞凋亡效应可能依赖于 HuR。此外，MAARS 敲低改变了 HuR 核细胞质运输，并调节重要的凋亡基因。这些观察结果为 MAARS 缺陷通过调节作用提供了基础 HuR和特定的巨噬细胞凋亡信号通路，减少巨噬细胞凋亡，改善细胞胞吞作用，并抑制动脉粥样硬化。为了进一步解决这个问题，在目标 1 中，我们研究了 MAARS 的作用调节 HuR 介导的巨噬细胞凋亡和胞吞作用；在 Aim2 中，我们评估如何改变 MAARS表达影响体内短期和长期动脉粥样硬化；在 Aim3 中，我们研究了人体细胞和动脉粥样硬化病变中的 MAARS-HuR 信号轴。我们的研究将解决一个主要问题我们对动脉粥样硬化中 lncRNA 的理解存在差距，并告知 MAARS 介导的控制巨噬细胞凋亡和胞吞作用可能为治疗提供新的靶点。