Neurotrophins in the Lung

肺中的神经营养素

• 批准号: 7792333
• 负责人: Y. S. Prakash
• 金额: $ 37.78万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7792333
• 关键词: Address; Affinity; Agonist; Area; Asthma; Biochemistry; Brain-Derived Neurotrophic Factor; Bronchoconstrictor Agents; Cells; Chronic Bronchitis; Cyclic ADP-Ribose; Data; Designer Drugs; Development; Disease; Family; Fluorescence; Foundations; Functional disorder; Generations; Goals; Growth Factor; Human; Hypersensitivity; Image; Immune; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Interleukins; Knock-in Mouse; Knowledge; Literature; Lung; Malignant Neoplasms; Malignant neoplasm of lung; Measurement; Mechanics; Mediating; Molecular Biology; Morphology; Mus; Muscle Contraction; Myosin Light Chains; Myosin Regulatory Light Chains; NGFR Protein; Nerve; Nerve Growth Factor Receptors; Nerve Growth Factors; Nervous system structure; Neurons; Neurotrophic Tyrosine Kinase Receptor Type 2; Neurotrophin 3; Ovalbumin; Pathway interactions; Pharmacology; Phospholipase C; Physiology; Publishing; Pulmonary Emphysema; Receptor Activation; Regulation; Relative (related person); Research; Resistance; Rho-associated kinase; Role; Ryanodine Receptor Calcium Release Channel; Ryanodine Receptors; Sarcoplasmic Reticulum; Second Messenger Systems; Shortness of Breath; Signal Transduction; Smooth Muscle; Smooth Muscle Myocytes; Source; Techniques; Tissues; Transgenic Mice; Tumor Necrosis Factor-alpha; Tumor Necrosis Factors; Up-Regulation; Work; airway hyperresponsiveness; airway inflammation; base; cytokine; immunocytochemistry; mouse model; neurotrophic factor; new therapeutic target; novel; public health relevance; receptor; receptor expression; respiratory smooth muscle; response; second messenger

DESCRIPTION (provided by applicant): An exciting, new investigative theme in airway physiology and pathophysiology is neurotrophins (NTs): growth factors including brain-derived neurotrophic factor (BDNF) known for their diverse roles in the nervous system. NTs and their receptors have now been found in different lung components including airway smooth muscle (ASM), with altered expression observed in asthma, allergy, and even lung cancer. While NTs may be derived from several sources, our published and preliminary data suggest that ASM is a target of NTs, and that NTs contribute not only to ASM contractility under normal circumstances, but also to increased contractility with airway inflammation (such as that induced by TNFa). The long term goal of the proposed studies is to understand the role of NTs in ASM physiology and pathophysiology. The overall hypothesis is that NTs enhance a) sarcoplasmic reticulum (SR) Ca2+ release and Ca2+ influx; and b) Ca2+ sensitivity for force generation in ASM. We propose that BDNF is a key NT influencing ASM contractility. Finally, airway inflammation enhances BDNF signaling, leading to an overall enhancement of [Ca2+]i and force. In this proposal, we will use human ASM and the ovalbumin (OVA) mouse model to examine the relative role of the BDNF receptors (high affinity TrkB vs. low affinity p75NTR) vis-¿vis ASM contractility. We hypothesize that TrkB is more important for [Ca2+]i regulation, while p75NTR regulates force. Using biochemistry, pharmacology, molecular biology, immunocytochemistry, fluorescence Ca2+ imaging, force measurement techniques, and lung mechanics, we will focus on specific mechanisms that may be regulated by BDNF: the second messengers IP3 (via phospholipase C PLC) and cyclic ADP ribose (via CD38) (Aim 1); SR Ca2+ release (IP3 receptor vs. ryanodine receptor (RyR) channels) (Aim 2); Ca2+ influx via store-operated Ca2+ entry (SOCE) (Aim 3) and the force regulatory mechanisms myosin light chain (MLC20) and rhoA/rho-kinase (Aim 4). These in vitro studies in human ASM will be integrated into the OVA mouse model applied in focus studies to the TrkB knockin mouse (where TrkB functionality is reversibly inhibited). We will explore the idea that inflammation induced by TNFa increases constitutive BDNF receptor expression, and alters specific [Ca2+]i and force regulatory mechanisms, thus priming ASM for enhanced response to both BDNF and bronchoconstrictor. The Specific Aims are: Aim 1: To determine mechanisms by which BDNF modulates second messenger signaling in human ASM; Aim 2: To determine mechanisms by which BDNF modulates SR Ca2+ regulation in human ASM; Aim 3: To determine mechanisms by which BDNF modulates SOCE in human ASM; Aim 4: To determine mechanisms by which BDNF modulates force regulation in human ASM; Aim 5: To determine the role of BDNF in ASM contractility in a mouse model of airway inflammation and hyperresponsiveness. PUBLIC HEALTH RELEVANCE. There is increasing recognition that abnormalities in airway smooth muscle contractility (exacerbated by inflammation) contribute to exaggerated airway narrowing and accompanying shortness of breath in clinically important diseases such as asthma and chronic bronchitis. In this regard, the potential role of growth factors called neurotrophins in regulation of airway contractility is an exciting and emerging area of research. By establishing the role of neurotrophins in airway narrowing with or without inflammation, the proposed studies will the foundation for better understanding of airway diseases, and potential development of new therapeutic targets.

描述（由申请人提供）：气道生理学和病理生理学中一个令人兴奋的新研究主题是神经营养因子（NT）：包括脑源性神经营养因子（BDNF）在内的生长因子，以其在神经系统中的多种作用而闻名。现在已经在不同的肺成分中发现了NT及其受体，包括气道平滑肌（ASM），在哮喘，过敏甚至肺癌中观察到表达改变。虽然NT可能来自几个来源，但我们发表的和初步的数据表明，ASM是NT的靶点，并且NT不仅在正常情况下有助于ASM收缩性，而且还有助于气道炎症（如TNF α诱导的）的收缩性增加。提出的研究的长期目标是了解NT在ASM生理学和病理生理学中的作用。总的假设是NT增强a）肌浆网（SR）Ca 2+释放和Ca 2+内流;和B）ASM中力产生的Ca 2+敏感性。我们建议，BDNF是一个关键的NT影响ASM的收缩性。最后，气道炎症增强BDNF信号传导，导致[Ca 2 +]i和力的整体增强。在这个提议中，我们将使用人类ASM和卵清蛋白（OVA）小鼠模型来研究BDNF受体（高亲和力TrkB与低亲和力p75 NTR）维斯维斯ASM收缩性的相对作用。我们假设TrkB对[Ca 2 +]i调节更重要，而p75 NTR调节力。利用生物化学、药理学、分子生物学、免疫细胞化学、荧光Ca 2+成像、力测量技术和肺力学，我们将重点关注可能由BDNF调节的特定机制：第二信使IP 3（通过磷脂酶C PLC）和环ADP核糖（通过CD 38）（目的1）; SR Ca 2+释放（IP 3受体与兰尼碱受体（RyR）通道）（Aim 2）;通过钙库操作的钙内流（SOCE）（目的3）和力调节机制肌球蛋白轻链（MLC 20）和rhoA/rho激酶（目的4）。这些人ASM的体外研究将整合到用于TrkB敲入小鼠（其中TrkB功能被可逆抑制）焦点研究的OVA小鼠模型中。我们将探讨TNF α诱导的炎症增加组成性BDNF受体表达，并改变特定的[Ca 2 +]i和力调节机制，从而引发ASM对BDNF和支气管收缩剂的反应增强的想法。具体目标是：目标1：确定BDNF调节人ASM中第二信使信号的机制;目的2：确定BDNF调节人ASM中SR Ca 2+调节的机制;目的3：确定BDNF调节人ASM中SOCE的机制;目的4：确定BDNF调节人ASM中力调节的机制;目的5：在小鼠气道炎症和高反应性模型中确定BDNF在ASM收缩中的作用。公共卫生相关性。越来越多的人认识到，气道平滑肌收缩性的异常（由炎症加剧）会导致过度的气道狭窄，并伴随着临床上重要的疾病，如哮喘和慢性支气管炎的呼吸急促。在这方面，称为神经营养因子的生长因子在调节气道收缩性中的潜在作用是一个令人兴奋的新兴研究领域。通过建立神经营养因子在有或无炎症的气道狭窄中的作用，所提出的研究将为更好地理解气道疾病和潜在的新治疗靶点的开发奠定基础。