Regulation of angiogenesis by nuclear receptors and cofactors

核受体和辅助因子对血管生成的调节

• 批准号: 8941966
• 负责人: VIHANG A NARKAR
• 金额: $ 42.38万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-02 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8941966
• 关键词: Affect; American; Angiogenic Factor; Area; Binding; Biological Assay; Blood Vessels; Cardiovascular Diseases; Chronic; Complication; Conditioned Culture Media; Data; Development; Diabetes Mellitus; Disease; Double Effect; Endothelial Cells; Fibrinogen; Gene Expression; Genes; Goals; Growth; Health; Impaired wound healing; In Vitro; Individual; Ischemia; Knock-out; Knockout Mice; Lead; Limb structure; Measures; Mediating; Metabolic; Metabolic Diseases; Molecular; Mus; Muscle; Muscle Cells; Myocardial Infarction; Myopathy; Names; Nuclear Hormone Receptors; Nuclear Orphan Receptor; Nuclear Receptors; Operative Surgical Procedures; PPAR gamma; Paracrine Communication; Pathology; Patients; Peripheral arterial disease; Pharmacologic Substance; Prevalence; Regulation; Regulator Genes; Repression; Research; Research Proposals; Role; Severities; Site; Skeletal Muscle; Stroke; Symptoms; Testing; Transgenic Mice; Tumor Angiogenesis; Ulcer; Vascular Endothelial Growth Factors; Vascular blood supply; Vascularization; Work; angiogenesis; chicken ovalbumin upstream promoter-transcription factor; cofactor; db/db mouse; diabetic; hypoxia inducible factor 1; improved; in vivo; innovation; limb amputation; novel; paracrine; prevent; programs; receptor; reconstruction; research study; therapeutic angiogenesis; treatment strategy; vessel regression

 DESCRIPTION (provided by applicant): Peripheral arterial disease (PAD) and its severe form critical limb ischemia (CLI) affect nearly 8 million Americans. Most patients with chronic metabolic and cardiovascular diseases such as diabetes also suffer from PAD/CLI. Patients with PAD/CLI suffer from debilitating symptoms such as immobility, ulceration, impaired wound healing, and intractable ischemia. The pathology of PAD/CLI involves vascular regression in the skeletal muscle, which leads to significant myopathy. Treatment is limited to surgical reconstruction, which is often costly and ineffective leading to limb amputations. 'Therapeutic angiogenesis' to improve muscle vascular supply is an urgent area of research in PAD/CLI. Within this field, focus has been on pro-angiogenic regulators such as vascular endothelial growth factor-alpha (Vegfa) and hypoxia inducible factor 1 (HIF1), and how they can improve muscle vasculature. Unfortunately, individual angiogenic factors and even HIF1 have so far been ineffective targets in PAD/CLI. Notably, skeletal muscle vascular supply and neo angiogenesis is controlled in a paracrine fashion by both pro-angiogenic and anti-angiogenic factors secreted by the muscle. While molecular regulation of pro-angiogenic factors such as Vegfa in the muscle is defined, surprisingly, the molecular regulation of anti-angiogenic factors is poorly defined. We have preliminarily found that a transcriptional cofactor peroxisome proliferator-activated receptor gamma co-activator 1 beta (PGC1β), which typically functions by activating nuclear hormone receptors, encodes an inhibitory angiogenesis gene program in the skeletal muscles. This program constitutes induction of anti-angiogenic factors and repression of proangiogenic factors, resulting in a net inhibition of skeletal muscle revascularization in ischemia. Interestingly, we found that PGC1β expression is induced along with the anti-angiogenic factors in diabetic muscles, which are characterized by the pathological symptoms of PAD/CLI such as vascular regression, ischemia and impaired neo-angiogenesis. Therefore, the first objective of this research proposal is to decipher the role of endogenous muscle PGC1β in regulating inhibitory angiogenic program and its effect on ischemic muscle revascularization and diabetic muscle angiopathy. The second objective is to establish COUP-TFI (chicken ovalbumin upstream promoter transcription factor I) as the nuclear receptor involved in PGC1β-driven inhibitory angiogenesis. Our preliminary data indicates that the anti-angiogenic effects of PGC1β may be mediated by activating nuclear receptor COUP-TFI. Our central hypothesis is that PGC1β in the skeletal muscle instigates a paracrine anti-angiogenic gene program by activating COUP-TFI, blocks ischemic neo angiogenesis, and contributes to diabetic muscle angiopathy. The specific aims to test this hypothesis are to: (Aim 1) Investigate the role of endogenous PGC1β in muscle angiogenesis and (Aim 2) Investigate whether PGC1β and COUPTFI interact to regulate muscle angiogenesis. In Aim 1, we will use muscle-specific deletion of PGC1β in mice to investigate how the loss of muscle PGC1β affects muscle vasculature, ischemic revascularization and the expression of angiogenic factors. In Aim 2, we will first perform in vitro experiments to study the interaction between PGC1β and COUP-TFI, and how they regulate muscle angiogenic genes. Second, we will use muscle-specific compound transgenic mice to investigate whether the anti-angiogenic effects of musclespecific PGC1β over-expression is lost on muscle-specific COUP-TFI deletion. We will also investigate the impact of double muscle-specific PGC1β and COUP-TFI knockout on muscle neo-angiogenesis and revascularization. The significance of our work is that it aims to discover how anti-angiogenic gene program is regulated in the skeletal muscle, and how it affects revascularization in muscle ischemia and diabetic muscle angiopathy. Our research is innovative as we will study the unexplored area of anti-angiogenic gene programming in the treatment of PAD/CLI. The findings will have implications for devising new treatment for muscle ischemia in PAD/CLI, and broadly in other diseases such as cardiac infarction, stroke and tumor angiogenesis.

 描述（由申请人提供）：周围动脉疾病 (PAD) 及其严重形式的严重肢体缺血 (CLI) 影响着近 800 万美国人。大多数患有慢性代谢疾病和心血管疾病（例如糖尿病）的患者也患有 PAD/CLI。 PAD/CLI 患者患有虚弱症状，如不能活动、溃疡、伤口愈合受损和顽固性缺血。 PAD/CLI 的病理涉及骨骼肌中的血管退化，从而导致严重的肌病。治疗仅限于手术重建，这通常成本高昂且效果不佳，导致截肢。改善肌肉血管供应的“治疗性血管生成”是 PAD/CLI 的一个紧迫研究领域。在该领域，重点关注促血管生成调节剂，例如血管内皮生长因子-α (Vegfa) 和缺氧诱导因子 1 (HIF1)，以及它们如何改善肌肉脉管系统。不幸的是，迄今为止，单个血管生成因子甚至 HIF1 都不是 PAD/CLI 的有效靶点。值得注意的是，骨骼肌血管供应和新血管生成由肌肉分泌的促血管生成因子和抗血管生成因子以旁分泌方式控制。虽然肌肉中促血管生成因子（例如 Vegfa）的分子调节已被定义，但令人惊讶的是，抗血管生成因子的分子调节尚不清楚。我们初步发现，转录辅助因子过氧化物酶体增殖物激活受体γ共激活因子1β（PGC1β）通常通过激活核激素受体发挥作用，在骨骼肌中编码抑制性血管生成基因程序。该程序包括抗血管生成因子的诱导和促血管生成因子的抑制，从而导致缺血时骨骼肌血运重建的净抑制。有趣的是，我们发现糖尿病肌肉中PGC1β的表达与抗血管生成因子一起被诱导，其特征是PAD/CLI的病理症状，如血管退化、缺血和新血管生成受损。因此，本研究计划的第一个目标是破译内源性肌肉PGC1β在调节抑制性血管生成程序中的作用及其对缺血性肌肉血运重建和糖尿病性肌肉血管病的影响。第二个目标是建立 COUP-TFI（鸡卵白蛋白上游启动子转录因子 I）作为参与 PGC1β 驱动的抑制性血管生成的核受体。我们的初步数据表明 PGC1β 的抗血管生成作用可能是通过激活核受体 COUP-TFI 介导的。我们的中心假设是，骨骼肌中的 PGC1β 通过激活 COUP-TFI 启动旁分泌抗血管生成基因程序，阻断缺血性新血管生成，并导致糖尿病性肌肉血管病。检验这一假设的具体目的是：（目标 1）研究内源性 PGC1β 在肌肉血管生成中的作用，以及（目标 2）研究 PGC1β 和 COUPTFI 是否相互作用来调节肌肉血管生成。在目标 1 中，我们将在小鼠中使用 PGC1β 的肌肉特异性缺失来研究肌肉 PGC1β 的缺失如何影响肌肉脉管系统、缺血性血运重建和血管生成因子的表达。在目标2中，我们将首先进行体外实验来研究PGC1β和COUP-TFI之间的相互作用，以及它们如何调节肌肉血管生成基因。其次，我们将使用肌肉特异性复合转基因小鼠来研究肌肉特异性 PGC1β 过度表达的抗血管生成作用是否因肌肉特异性 COUP-TFI 缺失而丧失。我们还将研究双肌肉特异性 PGC1β 和 COUP-TFI 敲除对肌肉新生血管生成和血运重建的影响。我们工作的意义在于，它旨在发现抗血管生成基因程序如何在骨骼肌中受到调节，以及它如何影响肌肉缺血和糖尿病肌肉血管病的血运重建。我们的研究具有创新性，因为我们将研究 PAD/CLI 治疗中尚未探索的抗血管生成基因编程领域。这些发现对于设计针对 PAD/CLI 肌肉缺血的新疗法以及广泛用于心肌梗死、中风和肿瘤血管生成等其他疾病的疗法具有重要意义。