Unravelling lung interoception and its functional consequence in the developing ovine lung

解开肺内感受及其在发育中的绵羊肺中的功能后果

• 批准号: 10320593
• 负责人: Arlin B Blood
• 金额: $ 62.14万
• 依托单位: LOMA LINDA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10320593
• 关键词: Acute; Address; Adult; Affect; Allergic; Alveolar; Animals; Apnea; Asthma; Autonomic nervous system; Behavioral; Bilateral; Birth; Blood; Blood Vessels; Brain; Brain Stem; Breathing; Bronchopulmonary Dysplasia; C Fiber; Cell Nucleus; Cerebral cortex; Cesarean section; Chemicals; Chronic; Communication; Computer software; Custom; Data; Denervation; Development; Dyes; Efferent Neurons; Electrodes; Embryo; Environment; Epithelial; Esthesia; Exercise; Feedback; Fetal Development; Fetal Lung; Fetal Sheep; Fetus; Foundations; Future; Gases; Goals; Growth; Growth and Development function; Human; Hypoxia; Immune response; Implant; Interoception; Irritants; Knowledge; Life; Link; Location; Lung; Lung diseases; Maintenance; Maps; Measures; Mechanics; Mechanoreceptors; Modeling; Modernization; Monitor; Morphology; Myography; Nature; Nerve; Neuraxis; Neurobiology; Neuroendocrine Cell; Neuroimmune; Neurons; Newborn Infant; Nodose Ganglion; Operative Surgical Procedures; Organ; Outcome Study; Pattern; Perinatal; Periodicity; Phase; Phenotype; Physiology; Play; Population; Pregnancy; Prevalence; Pulmonary Gas Exchange; Pulmonary artery structure; Research; Respiration; Respiratory physiology; Role; Sensory; Series; Sheep; Signal Transduction; Stress; Structure; Sudden infant death syndrome; Synapses; Techniques; Testing; The Sun; Thinness; Time; Tissues; Tracer; Vagus nerve structure; Viral; Work; afferent nerve; airway epithelium; course development; environmental stressor; experience; fetal; fetus hypoxia; human model; instrument; loss of function; lung development; methacholine; microbial; nerve supply; nervous system development; neural circuit; neural network; neurotransmission; novel; pathogen; postnatal; premature; pulmonary function; receptor; relating to nervous system; respiratory; response; sheep model; transcriptome sequencing

Project Summary The interoceptive link between the lung and CNS carries mechanical and irritant information to its first-order synapse in the brainstem. This information is critical in the newborn and adult for maintenance of pulmonary gas exchange in the face of behavioral changes and environmental stressors, and in orchestrating immune responses to viral, bacterial, and allergic pathogens. Although the fetal lung is richly innervated during development, the connectivity to the central nervous system (CNS), the extent to which these neurons help orchestrate lung and CNS formation over the course of development, and the role they play in function at birth remain largely unknown. This R01 application proposes to address this knowledge gap using a novel fetal sheep model. We hypothesize that intrinsic and extrinsic lung interoceptive units play a role in the normal development of the lung and central respiratory control centers. We will test this in the following aims: Aim 1: Traditional dye and novel viral track tracer techniques will be used in fetal sheep at various stages of lung development to delineate the location and connectivity of the interoceptive units within the lung, as well as first- and second-order central circuitry to and above the brainstem. The effect of surgical denervation on lung developmental morphology and the prevalence of various neural populations involved in chemo- and irritant sensation, including A- and C-fiber neurons involved in breathing control, and pulmonary neuroendocrine cells involved in pulmonary mechano- and chemosensation. Finally, single neuron RNAseq will be used to phenotypically characterize neurons within the fetal jugular and nodose ganglia at various stages of development. Aim 2: To test the necessity of interroception on fetal lung development and respiratory function after birth, fetuses in the canalicular stage will be subjected to either bilateral denervation of the lungs or periodic hyperstimulation of mechanoreceptors via overinflation for the remainder of gestation. Pulmonary vascular function, airway mechanics, and gas exchange will then be monitored following c-section delivery and in response to acute hypoxia and methacholine challenges, and responses will be compared to both sham and naive controls. Aim 3: Vagal ascending and descending nerve traffic will be recorded in fetuses instrumented with state-of-the-art cuff electrodes throughout fetal development and at birth. Custom time-series and spectral analysis software will be used to quantify changes in afferent/efferent vagal nerve signaling in response to pulmonary denervation, birth, and mechano- and chemosensory stimulations. The outcomes of these studies will fill in critical knowledge gaps of the role of interoception in lung development and function in a sheep model that has been a historically signature model of human perinatal lung development and physiology. Our proposed foundational work will inform future efforts focused on a variety of lung diseases in humans that originate during development, such as bronchopulmonary dysplasia, apnea of prematurity, sudden infant death syndrome, and asthma.

项目摘要 肺和中枢神经系统之间的相互感觉联系将机械和刺激性信息传递到脑干的一级突触。这些信息对于新生儿和成人在面对行为变化和环境应激源时维持肺气体交换，以及在协调对病毒、细菌和过敏性病原体的免疫反应方面至关重要。虽然胎肺在发育过程中受到丰富的神经支配，但与中枢神经系统(CNS)的连接，这些神经元在发育过程中在多大程度上帮助协调肺和CNS的形成，以及它们在出生时发挥的功能在很大程度上仍不清楚。这个R01应用程序建议使用一种新的胚胎绵羊模型来解决这一知识差距。 我们假设内源性和外源性肺内感受器单位在肺和中枢呼吸控制中心的正常发育中发挥作用。我们将在以下目标中进行测试：目标1：传统染料和新型病毒示踪技术将用于不同肺发育阶段的胚胎绵羊，以描绘肺内相互感受单位的位置和连接，以及通往脑干和脑干上方的一阶和二阶中枢回路。手术去神经对肺发育形态的影响以及参与化学和刺激性感觉的各种神经细胞的流行情况，包括参与呼吸控制的A和C纤维神经元，以及参与肺机械和化学感觉的肺神经内分泌细胞。最后，单个神经元RNAseq将被用于表征胎儿颈静脉和结状神经节中不同发育阶段的神经元的表型。目的：为了验证交互作用对胎儿出生后肺发育和呼吸功能的影响，对处于肺小管阶段的胎儿进行双侧肺去神经或通过过度充气周期性机械感受器过度刺激。然后，将监测剖腹产后的肺血管功能、呼吸道力学和气体交换情况，以及对急性缺氧和乙酰甲胆碱挑战的反应，并将反应与假手术和幼稚对照进行比较。目的3：在胎儿发育过程中和出生时，使用最先进的袖带电极测量胎儿的迷走神经上行和下行神经流量。定制的时间序列和频谱分析软件将用于量化传入/传出迷走神经信号的变化，以响应肺去神经、分娩以及机械和化学感觉刺激。 这些研究的结果将填补在绵羊模型中内感觉在肺发育和功能中作用的关键知识空白，绵羊模型一直是人类围产期肺发育和生理的标志性模型。我们提议的基础性工作将为未来专注于人类发育期间各种肺部疾病的研究提供信息，例如支气管肺发育不良、早产儿呼吸暂停、婴儿猝死综合征和哮喘。