PlGF-HIF1a-miRNA Axis in Sickle Pulmonary Hypertension

镰状型肺动脉高压中的 PlGF-HIF1a-miRNA 轴

• 批准号: 8600723
• 负责人: VIJAY K. KALRA
• 金额: $ 60.46万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 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/8600723
• 关键词: 3' 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

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.

项目摘要 肺部高血压（PHT）发生在约30％的镰状细胞贫血（SCA）的患者中，导致约50％ 诊断2年内的死亡率。这种血管病的发病机理可能是多因素的，潜在的 通过溶血引起的一氧化氮生物利用度受损，慢性血栓栓塞产生 状态并增加内皮素-1（ET-1）。我们的研究表明，Pleceta生长因子（PLGF）， 镰状红细胞细胞以高量产生的血管生成因子，诱导有效的表达 肺血管收缩剂ET-1和人类的Procogulans纤溶酶原激活剂抑制剂1（PAI-1） 肺微血管内皮细胞（HPMVEC）。 PLGF通过 诱导低氧诱导因子-1。（HIF-1？）。 PHT可以通过Ecopic PLGF实验诱导 在以ET-1为特征的正常小鼠中的表达，如在转基因小鼠和 SCA患者。我们最近观察到，HPMVEC中PLGF介导的HIF-1和PAI-1的诱导是 - 由三个特定microRNA（miR）调节的转录调节。对邮政的了解相对鲜为人知。 转录，miR介导的HIF-1A，ET-1和PAI-1或RNA结合蛋白的调节表达 这稳定了促进PHT的这些基因的mRNA。我们的总体假设是细胞质 RNA结合蛋白和miRNA改变了HIF-1 eT-1和PAI-1 mRNA的稳定性，直接是 参与PHT的发展。为了解决这一假设，在AIM 1中，我们将确定后 转录机制调节PLGF介导的HIF-1A，ET-1和PAI-1的表达并鉴定 RNA结合蛋白和与mRNA 3'UTRS结合的特定miR因此调节 HIF-1A，ET-1和PAI-1 mRNA。在AIM 2中，我们将确定调节PAI-1的miR基因是否是否 表达，位于NFYC和SKA2基因的内含子内，是从NFYC共同合成的，并且 SKA2主转录本，或独立于较小的MIRNA转录单元转录。目标 3，我们将证明这些miR在hif-1，et-1和pai-1中的要求 过表达PLGF并开发PHT的鼠标模型。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至等离子体PLGF，ET-1和PAI-1的水平。 这些研究将提高我们关于RNA结合蛋白和miR如何调节某些关键的知识 与镰状PHT有关的基因，以及这些miRNA的表达本身如何调节。这些研究可能会 提供新的诊断生物标志物来评估PHT，并为这种疾病的新型治疗靶标提供 目前几乎没有或没有治疗选择。