PlGF-HIF1a-miRNA Axis in Sickle Pulmonary Hypertension

镰状型肺动脉高压中的 PlGF-HIF1a-miRNA 轴

基本信息

批准号：
8403676
负责人：
VIJAY K. KALRA
金额：
$ 58.68万
依托单位：
UNIVERSITY OF SOUTHERN CALIFORNIA
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-01-01 至 2016-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8403676
关键词：
3&apos Untranslated Regions Address Adenovirus Vector Binding Biological Availability Cells Cessation of life Chronic Clinical Coronary artery Death Rate Development Diagnosis Disease Ectopic Expression Embolism Endothelial Cells Endothelin-1 Erythroid Cells Ethanol Genes Genetic Genetic Polymorphism Genetic Transcription Growth Factor Hemolysis Human Hypoxia In Situ Inflammation Introns Knockout Mice Knowledge Laboratories Lentivirus Vector Lung Mediating Messenger RNA MicroRNAs Morbidity - disease rate Mus Nitric Oxide Odds Ratio Pathogenesis Patients Placental Growth Factor Plasma Plasminogen Activator Inhibitor 1 Play Post-Transcriptional Regulation Production Pulmonary Fibrosis Pulmonary Hypertension Pulmonary artery structure Pulmonary vessels RNA-Binding Proteins Regulation Risk Role Sickle Cell Anemia Smooth Muscle Symptoms Testing Therapeutic Thrombosis Transcript Transgenic Organisms Translations Vascular Diseases Vascular remodeling Vasoconstrictor Agents Wild Type Mouse dosage hypoxia inducible factor 1 in vivo locked nucleic acid mortality mouse model new therapeutic target novel diagnostics pre-miRNA pressure sickle erythroid sickling transcription factor

项目摘要

Project Summary Pulmonary hypertension (PHT) occurs in ~30% of patients with sickle cell anemia (SCA) and results in ~50% mortality within 2 years of diagnosis. The pathogenesis of this vasculopathy is likely multi-factorial, potentiated by hemolysis-induced impaired nitric oxide bioavailability, chronic thrombo-embolism from a procoagulant state, and increased endothelin-1 (ET-1). Our studies have shown that placenta growth factor (PlGF), an angiogenic growth factor produced in high amounts by sickle erythroid cells, induces expression of the potent pulmonary vasoconstrictor ET-1, and a procoagulant, plasminogen activator inhibitor-1 (PAI-1), from human pulmonary microvascular endothelial cells (HPMVEC). PlGF increases ET-1 and PAI-1 expression via induction of hypoxia-inducible factor-1¿ (HIF-1¿). PHT can be induced experimentally by ectopic PlGF expression in normal mice characterized by increased ET-1, as is observed in transgenic sickle mice and in SCA patients. We recently observed that PlGF-mediated induction of HIF-1¿ and PAI-1 in HPMVEC is post- transcriptionally regulated by three specific microRNAs (miRs). Relatively little is known of the post- transcriptional, miR-mediated, regulated expression of HIF-1a, ET-1 and PAI-1, or of the RNA-binding proteins that stabilize the mRNAs of these genes that promote PHT. Thus our overall hypothesis is that cytoplasmic RNA-binding proteins and miRNAs alter the stability of HIF-1¿, ET-1, and PAI-1 mRNAs, and are directly involved in the development of PHT. To address this hypothesis, in Aim 1, we will determine the post- transcriptional mechanisms which regulate PlGF-mediated expression of HIF-1a, ET-1 and PAI-1 and identify RNA binding proteins and the specific miRs involved in binding to mRNA 3'UTRs thus regulating translation of HIF-1a, ET-1, and PAI-1 mRNAs. In Aim 2, we will determine whether the genes for miRs that regulate PAI-1 expression, and are located within introns of NFYC and SKA2 genes are co-synthesized from the NFYC and SKA2 primary transcripts, or are independently transcribed from a smaller, pre-miRNA transcription unit. In Aim 3, we will demonstrate the requirement of these miRs in the regulation of HIF-1¿, ET-1 and PAI-1 in genetic mouse models that over-express PlGF and develop PHT. Finally, we will determine the association of plasma levels of these miRNAs to plasma PlGF, ET-1 and PAI-1 in SCA patients with and without PHT symptoms. These studies will advance our knowledge as to how RNA binding proteins and miRs regulate some of the key genes involved in sickle PHT, and how expression of these miRNAs is itself regulated. These studies will likely provide new diagnostic bio-markers for assessment of PHT, and novel therapeutic targets for a disease that currently has few or no therapeutic options.

项目概要约 30% 的镰状细胞性贫血 (SCA) 患者会出现肺动脉高压 (PHT)，并导致约 50% 的患者出现肺动脉高压 (PHT) 诊断后 2 年内死亡这种血管病的发病机制可能是多因素的、强化的。由溶血引起的一氧化氮生物利用度受损、促凝血剂引起的慢性血栓栓塞我们的研究表明，胎盘生长因子 (PlGF) 会增加。镰状红细胞大量产生的血管生成生长因子，诱导有效的表达肺血管收缩剂 ET-1 和促凝血剂纤溶酶原激活剂抑制剂-1 (PAI-1)，来自人类肺微血管内皮细胞 (HPMVEC) 通过增加 ET-1 和 PAI-1 的表达。诱导缺氧诱导因子-1¿ (HIF-1¿) 可以通过异位 PlGF 实验诱导。正常小鼠中的表达以 ET-1 增加为特征，如在转基因镰状小鼠和我们最近观察到 PlGF 介导的 HIF-1 诱导。 HPMVEC 中的 PAI-1 是后转录后的调控机制目前还不清楚。 HIF-1a、ET-1 和 PAI-1 或 RNA 结合蛋白的转录、miR 介导、调节表达稳定这些促进 PHT 的基因的 mRNA，因此我们的总体假设是细胞质。 RNA 结合蛋白和 miRNA 改变 HIF-1 的稳定性、ET-1 和 PAI-1 mRNA，并且直接为了解决这个假设，在目标 1 中，我们将确定后期。调节 PlGF 介导的 HIF-1a、ET-1 和 PAI-1 表达的转录机制并鉴定 RNA 结合蛋白和参与与 mRNA 3'UTR 结合从而调节翻译的特定 miR HIF-1a、ET-1 和 PAI-1 mRNA 在目标 2 中，我们将确定 miR 的基因是否调节 PAI-1。表达，位于 NFYC 和 SKA2 基因的内含子内，由 NFYC 和 SKA2 基因共同合成。 SKA2 初级转录物，或由较小的 pre-miRNA 转录单位独立转录。 3，我们将证明这些 miRs 在 HIF-1 调节中的需求¿ 、 ET-1 和 PAI-1 在遗传中过度表达 PlGF 并发生 PHT 的小鼠模型最后，我们将确定血浆的关联。在有或没有 PHT 症状的 SCA 患者中，这些 miRNA 的血浆 PlGF、ET-1 和 PAI-1 水平。这些研究将增进我们对 RNA 结合蛋白和 miR 如何调节一些关键蛋白的了解。这些研究可能会揭示参与镰状 PHT 的基因，以及这些 miRNA 的表达本身是如何受到调节的。为评估 PHT 提供新的诊断生物标志物，并为这种疾病提供新的治疗靶点目前几乎没有或没有治疗选择。