Long non-coding RNA-mediated chromatin remodeling in angiogenesis

项目摘要/摘要 糖尿病血管生成障碍并发外周动脉疾病(PAD)，这是一种由疼痛引起的疾病 动脉粥样硬化会减少流向四肢的血流量。表观遗传机制 (例如，DNA甲基化、染色质修饰和构象变化，以及长的非编码RNA) 与持续的糖尿病并发症有关。然而，这些条件是否以及如何影响 血管内皮细胞的表观遗传状态，进而导致血管生成功能的慢性损害 内皮细胞(ECs)在很大程度上仍不清楚。我们之前发现了一种增强子相关的lncRNA 调节内皮型一氧化氮合酶(ENOS)，我们将其命名为增强eNOS的lncRNA 表达“(Leene)。我们的初步发现支持Leene在监管中扮演一个新的和重要的角色 血管生成的影响。在糖尿病条件下，Leene在小鼠和人类的内皮细胞中受到抑制；以及 Leene的恢复挽救了高糖(HG)受损的血管生成。从机制上讲，Leene提升了 染色质可及性、组蛋白修饰和启动子区域的转录因子结合 驱动血管生成基因的表达。我们还建立了一个带有Leene基因缺失的小鼠模型， 这使我们能够测试Leene在血管功能中的重要性，特别是在糖尿病的情况下- 关联的地坪。我们的中心假设是Leene促进生理性血管生成，而且 糖尿病患者抑制Leene(通过HG)会损害血管生成，从而导致血管并发症 例如PAD。为了检验这一假设，我们提出了三个目标。在目标1中，我们将阐明分子 Leene在生理条件下促进血管生成基因表达的机制。在目标2中， 我们将确定HG抑制Leene以损害血管生成的机制。在《目标3》中，我们将 在体内确定Leene在糖尿病相关PAD中的功能重要性。总而言之，我们的研究将 应用创新的方法来描绘这一以前未曾探索过的血管生成和 为糖尿病患者血管生成受损如何导致血管并发症提供新的见解。 我们希望我们的研究结果对心血管疾病具有深远的临床和治疗意义。 涉及异常的血管生成。

Project Summary/Abstract Diabetic impairment of angiogenesis complicates peripheral arterial disease (PAD), a painful disorder caused by atherosclerosis in the arteries that reduces blood flow to the lower extremities. Epigenetic mechanisms (e.g., DNA methylation, chromatin modifications and conformational change, and long non-coding RNAs) are implicated in sustained diabetic complications. However, whether and how these conditions influence the epigenetic state of the vascular endothelium and, in turn, cause a chronic impairment in angiogenic function of endothelial cells (ECs) remains largely unknown. We previously identified an enhancer-associated lncRNA that regulates endothelial nitric oxide synthase (eNOS), which we named “lncRNA that enhances eNOS expression” (LEENE). Our preliminary findings support a novel and essential role for LEENE in the regulation of angiogenesis. Under diabetic conditions, LEENE is suppressed in the ECs of mice and humans; and restoration of LEENE rescues high glucose (HG)-impaired angiogenesis. Mechanistically, LEENE promotes the chromatin accessibility, histone modification, and transcription factor binding at the promoter regions driving angiogenic gene expression. We have also generated a mouse model with genetic deletion of leene, which enables us to test the importance of leene in vascular function, particularly in the context of diabetes- associated PAD. Our central hypothesis is that LEENE promotes physiological angiogenesis, and that suppression of LEENE in diabetes (via HG), impairs angiogenesis, thus contributing to vascular complications such as PAD. To test this hypothesis, we propose three Aims. In Aim 1, we will elucidate the molecular mechanisms by which LEENE promotes angiogenic gene expression under physiological conditions. In Aim 2, we will define the mechanisms by which HG suppresses LEENE to impair angiogenesis. In Aim 3, we will determine the functional importance of LEENE in diabetes-associated PAD in vivo. Collectively, our study will apply innovative approaches to delineate this previously unexplored mechanism underlying angiogenesis and provide novel insights into how angiogenesis is impaired in diabetes to contribute to vascular complications. We expect our results to have far-reaching clinical and therapeutic implications for cardiovascular diseases involving aberrant angiogenesis.