Altered Lymphatics in an Ovine Cardiac Model of Increased Pulmonary Blood Flow

描述(由申请人提供)：这是一个指导培训计划的建议，旨在发展翻译心肺研究的学术生涯。应聘者已经成功地完成了加州大学旧金山分校(UCSF)儿科危重护理医学的临床和研究奖学金，现在准备充分发展和完善维持独立研究计划所需的技能，利用加州大学旧金山分校心血管研究所(CVRI)提供的著名的多学科环境。候选人将利用一种综合的方法来解决与先天性心脏病和肺血流量增加(PBF)相关的肺液稳态的机制。导师杰弗里·R·芬曼医学博士是加州大学旧金山分校CVRI的儿科学教授和研究员。他是一位国际公认的肺血管疾病专家，并有极强的成功指导历史。此外，由杰出生物医学研究人员组成的咨询委员会将就该提案的关键方面提供关键的科学审查：Michael Matthay博士、Donald McDonald博士和Dallas Hyde博士分别以肺水和肺损伤、肺淋巴管以及体视学和肺结构领域的专业知识而闻名世界。该研究计划试图在与常见先天性心脏病相关的PBF增加的背景下阐明肺液稳态的潜在机制。利用一个独特的、具有临床相关性的先天性心脏缺陷绵羊模型(在子宫内通过手术植入的主肺移植物建立)，我们产生了体内数据，表明慢性PBF增加与(1)相对淋巴流量受损，(2)生物可用一氧化氮减少，(3)肺淋巴管转运动力学延迟，(4)淋巴管结构异常，以及(5)与淋巴生长相关的蛋白表达的变化，如血管内皮生长因子-c。基于这些发现，我们的总体假设是，慢性PBF增加会导致肺淋巴管内皮功能受损，从而导致淋巴管流动和出生后发育的紊乱。通过整合整体动物、基于器官的实验、分子实验、分离血管实验、细胞培养实验和生化实验，本研究试图完成以下工作：描述慢性PBF升高对肺液平衡的影响，并阐明控制这些变化的机制。特别是，调节肺淋巴管功能和出生后淋巴管生长和重塑的信号通路将被研究。

DESCRIPTION (provided by applicant): This is a proposal for a mentored training program designed to develop an academic career in translational cardiopulmonary research. The candidate has successfully completed a clinical and research fellowship in Pediatric Critical Care Medicine at the University of California, San Francisco (UCSF), and is now prepared to fully develop and refine skills necessary to sustain an independent research program, utilizing the renowned, multidisciplinary environment offered by the Cardiovascular Research Institute (CVRI) at UCSF. The candidate will utilize an integrated approach to address mechanisms of lung fluid homeostasis associated with congenital heart defects and increased pulmonary blood flow (PBF). The mentor, Jeffrey R. Fineman, M.D., is Professor of Pediatrics and Investigator in the CVRI at UCSF. He is an internationally recognized expert on pulmonary vascular disease, and has an extremely strong history of successful mentorship. In addition, an advisory committee of distinguished biomedical investigators will provide critical scientific review on key aspects of this proposal: Drs. Michael Matthay, Donald McDonald, and Dallas Hyde are world-renowned for their expertise in the field of lung water and lung injury, lung lymphatics, and stereology and lung structure, respectively. The research plan seeks to elucidate the mechanisms underlying lung fluid homeostasis in the context of increased PBF that is associated with common congenital heart defects. Utilizing a unique, clinically relevant ovine model of a congenital heart defect with increased PBF (created in utero by a surgically-placed aortopulmonary graft), we have generated in vivo data indicating that chronically increased PBF is associated with (1) impaired relative lymphatic flow, (2) decreased bioavailable nitric oxide, (3) delayed transit kinetics through the pulmonary lymphatics, (4) aberrations in lymphatic architecture, and (5) alterations in the expression of proteins associated with lymphatic growth, such as vascular endothelial growth factor-c. Based on these findings, our overall hypothesis is that chronically increased PBF leads to impaired pulmonary lymphatic endothelial function, resulting in perturbation in lymphatic flow and postnatal development. By integrating whole animal, organ-based, molecular, isolated vessel, cell-culture, and biochemical experiments, this proposal seeks to accomplish the following: to characterize the effects of chronic increases in PBF on lung fluid balance, and to elucidate the mechanisms controlling these changes. In particular, the signaling pathways that regulate pulmonary lymphatic vascular function and post-natal lymphatic growth and remodeling will be examined.