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: 8219269
• 负责人: VIJAY K. KALRA
• 金额: $ 63.51万
• 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/8219269
• 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; Hypoxia Inducible Factor; 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

DESCRIPTION (provided by applicant): 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-11 (HIF-11). 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-11 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-11, 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-11, 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. PUBLIC HEALTH RELEVANCE: Pulmonary hypertension (PHT) is associated with high death rate among sickle cell anemia patients. We have found that genes (e.g. endothelin-1) associated with PHT are increased in these patients, and we propose to study specific microRNAs involved in their regulation.

描述（由申请人提供）：肺部高血压（PHT）发生在约30％的镰状细胞贫血（SCA）患者中，并在诊断后的2年内导致约50％的死亡率。这种血管病的发病机制可能是多因素的，这是由于溶血引起的一氧化氮生物利用度受损，proc凝状态的慢性血栓栓塞和增加的内皮素-1（ET-1）而增强的。我们的研究表明，胎盘生长因子（PLGF）是镰状红骨细胞高量产生的血管生成因子，诱导了人肺管微血管造型细胞（HPMVEC）。 PLGF通过诱导低氧诱导因子-11（HIF-11）来增加ET-1和PAI-1表达。如在转基因小鼠和SCA患者中所观察到的，可以通过异位PLGF表达在以ET-1为特征的正常小鼠中通过异位PLGF表达来实验诱导PHT。我们最近观察到，HPMVEC中PLGF介导的HIF-11和PAI-1的诱导在转录后由三个特定microRNA（MIR）在转录后调节。对于HIF-1A，ET-1和PAI-1的转录后，miR介导的，调控的表达或RNA结合蛋白稳定这些促进PHT的基因的mRNA的RNA结合蛋白，相对较少知道。因此，我们的总体假设是细胞质RNA结合蛋白和miRNA改变了HIF-11，ET-1和PAI-1 mRNA的稳定性，并直接参与PHT的发展。为了解决这一假设，在AIM 1中，我们将确定调节PLGF介导的HIF-1A，ET-1和PAI-1表达的转录后机制，并鉴定RNA结合蛋白以及与mRNA 3'UTRS结合的特定miRS，从而调节HIF-1A，ET-1和PAI-1 MRNAS的翻译。在AIM 2中，我们将确定调节PAI-1表达的miR的基因是在NFYC和SKA2基因内含子内的基因，是从NFYC和SKA2主要转录物共同合成的，还是从较小的，较小的pre-miRNA转录单元中独立转录。在AIM 3中，我们将在过度表达PLGF和发展PHT的遗传小鼠模型中证明这些miR在调节HIF-11，ET-1和PAI-1中的要求。最后，我们将确定在有或没有PHT症状的SCA患者中，这些miRNA的血浆水平与血浆PLGF，ET-1和PAI-1的关联。这些研究将提高我们关于RNA结合蛋白和miR的知识如何调节与镰状PHT有关的一些关键基因，以及这些miRNA的表达本身如何调节。这些研究可能会为评估PHT评估的新诊断生物标志物，以及目前几乎没有治疗选择的疾病的新型治疗靶标。 公共卫生相关性：肺动脉高压（PHT）与镰状细胞贫血患者的死亡率高有关。我们发现，这些患者中与PHT相关的基因（例如内皮素-1）的基因（例如，我们建议研究参与其调节的特定microRNA）。