Mechanisms driving endothelial angiopoietin-2 expression and vascular dysfunction during pediatric sepsis

小儿脓毒症期间内皮血管生成素 2 表达和血管功能障碍的驱动机制

• 批准号: 10684768
• 负责人: Robert P Richter
• 金额: $ 18.23万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-10 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10684768
• 关键词: Adenosine Monophosphate; Angiopoietin-2; Attenuated; Automobile Driving; Benchmarking; Binding; Biological Markers; Biology; Blood Vessels; Career Mobility; Cell secretion; Cell surface; Cells; Cessation of life; Child; Clinical; Clinical Research; Data; Dedications; Development; Development Plans; Endothelial Cells; Endothelium; Flow Cytometry; Fostering; Functional disorder; Funding; Glycocalyx; Goals; Health; Heparitin Sulfate; Hospital Mortality; Hour; Human; Impairment; In Vitro; Injury; Institution; International; Knowledge; Measures; Mediating; Mentors; Mentorship; Modeling; Modern Medicine; Morbidity - disease rate; Mus; Observational Study; Organ; Outcome; Pathology; Pathway interactions; Permeability; Physicians; Plasma; Process; Productivity; Property; Protein Kinase; Research; Research Training; Resources; Role; STK11 gene; Scientist; Sepsis; Signal Pathway; Signal Transduction; Surface; TIE-2 Receptor; Techniques; Testing; Therapeutic; Training; Training Programs; Translational Research; United States National Institutes of Health; Vascular Diseases; Vascular Permeabilities; Work; antagonist; autocrine; career; career development; clinical translation; electric impedance; endothelial dysfunction; exosome; gain of function; in vivo; lung microvascular endothelial cells; mRNA Expression; monolayer; mortality; nanoparticle; neutralizing antibody; novel; novel therapeutics; organ injury; paracrine; pediatric sepsis; programs; promoter; prospective; protein expression; septic; shear stress; small molecule; therapeutic target; translational scientist; vascular endothelial dysfunction; vascular injury

This K08 proposal describes a 5-year research training program that will prepare the candidate for a career as an independent, NIH-funded translational scientist focused on mechanisms driving sepsis-mediated vascular disease. The scientific premise for the aims is that vascular endothelial dysfunction is a key driver of organ injury in pediatric sepsis. Morbidity and mortality remain unacceptably high in pediatric sepsis despite advances in modern medicine, principally due to knowledge gaps in the mechanisms driving vascular disease during sepsis. Endothelial cell-derived angiopoietin-2 (Ang-2) has emerged as a critical promoter of vascular injury and organ impairment in sepsis through its antagonism of the endothelial Tie2 receptor. Plasma Ang-2 levels are significantly elevated in children with sepsis and are associated with measures of organ injury and outcomes. Preliminary data suggest that heparan sulfate cleavage from the surface glycocalyx of flow conditioned primary human lung microvascular endothelial cells promotes Ang-2 expression, implicating a novel paradigm by which Ang-2 is upregulated in sepsis. Preliminary data and prior work also suggest that inactivation of liver kinase B1 (LKB1) and downstream adenosine-monophosphate-activated protein kinase (AMPK) may be integral in this process. Further, the candidate discovered that Ang-2 is bound to the surface of exosomes isolated from plasma of septic children, suggesting that exosomal Ang-2 may significantly contribute to vascular disease and organ injury during sepsis. Together, these data support the novel mechanistic hypothesis that enzymatic heparan sulfate erosion from the endothelial glycocalyx during pediatric sepsis upregulates expression of Ang-2 that, when bound to exosomes, has potent vascular destabilizing effects. To test this hypothesis, in vitro, ex vivo, and clinical studies will be performed in the following two aims. Aim 1: Test the hypothesis that glycocalyx heparan sulfate erosion increases Ang-2 expression from flow conditioned human lung microvascular endothelial cells via attenuated LKB1 activity and downstream AMPK pathway signaling. Aim 2: Test the hypothesis that exosomal Ang-2 (a) is biomarker for organ injury and clinical outcomes in pediatric sepsis and (b) promotes endothelial permeability via Tie2 receptor antagonism. Harnessing the combined expertise of the candidate’s mentoring team and utilizing the wealth of resources available at the candidate’s institution, the candidate will train in advanced translational science techniques germane to the completion of these aims, including microvascular flow modeling, nanoparticle tracking analysis and characterization with flow cytometry, and electric cell-substrate impedance sensing. The proposed research program has defined benchmarks that will facilitate the candidate’s career advancement and will culminate in the submission of an R01 to continue uncovering the mechanisms driving vascular disease in pediatric sepsis that will foster the discovery of novel therapeutics.

本K 08提案描述了一个为期5年的研究培训计划，该计划将为候选人的职业生涯做好准备， 一位独立的，NIH资助的翻译科学家，专注于驱动脓毒症介导的血管 疾病这些目标的科学前提是血管内皮功能障碍是器官损伤的关键驱动因素 儿科败血症尽管在儿科败血症的发病率和死亡率方面取得了进展， 现代医学，主要是由于知识差距的机制，驱动血管疾病在败血症。 内皮细胞源性血管生成素-2（Ang-2）已成为血管损伤和器官损伤的关键促进剂。 通过其对内皮Tie 2受体的拮抗作用在脓毒症中的损害。血浆Ang-2水平 在脓毒症儿童中显著升高，并与器官损伤和结果的测量相关。 初步数据表明，硫酸乙酰肝素从流动调节的原代细胞表面糖萼裂解， 人肺微血管内皮细胞促进Ang-2的表达，这暗示了一种新的模式， Ang-2在脓毒症中上调。初步数据和先前的工作也表明，肝激酶B1的失活 LKB 1和下游的腺苷一磷酸活化蛋白激酶（AMPK）可能是这一过程中不可或缺的一部分。 过程此外，该候选人发现Ang-2与从血浆中分离的外泌体表面结合， 脓毒症儿童，这表明外泌体Ang-2可能显着有助于血管疾病和器官 脓毒症期间的损伤。总之，这些数据支持酶促乙酰肝素 儿科脓毒症期间内皮糖萼的硫酸盐侵蚀上调Ang-2的表达， 当与外来体结合时，具有强有力的血管去稳定作用。为了验证这一假设，在体外，离体， 临床研究将按以下两个目标进行。目的1：检验糖萼类肝素 硫酸盐侵蚀增加流动条件下人肺微血管内皮细胞Ang-2表达 通过减弱LKB 1活性和下游AMPK通路信号传导。目标2：检验假设， 外泌体Ang-2（a）是儿科脓毒症中器官损伤和临床结果的生物标志物，和（B）促进 通过Tie 2受体拮抗作用实现内皮渗透性。利用候选人的综合专长， 辅导团队和利用丰富的资源，在候选人的机构，候选人将 培养与实现这些目标密切相关的先进转化科学技术，包括 微血管流动建模，纳米颗粒跟踪分析和流式细胞术表征，以及电 细胞基质阻抗检测。拟议的研究计划已经确定了基准，将促进 候选人的职业发展，并将最终在提交R 01继续揭露 在儿科败血症中驱动血管疾病的机制，这将促进新疗法的发现。

项目成果

International Perspective on a Revised Pediatric Sepsis Definition.

• DOI: 10.1542/peds.2022-056410
• 发表时间: 2022-06-01
• 期刊: PEDIATRICS
• 影响因子: 8
• 作者: Richter, Robert P.

Pediatric Ventilation Liberation: Bundled Extubation Readiness and Analgosedation Pathways Decrease Mechanical Ventilation Duration and Benzodiazepine Exposure.

儿科通气解放：捆绑拔管准备和镇静途径可减少机械通气持续时间和苯二氮卓类药物暴露。

• DOI: 10.4187/respcare.09942
• 发表时间: 2022
• 期刊: Respiratory care
• 影响因子: 2.5
• 作者: Loberger,JeremyM;Waddell,KristenC;Prabhakaran,Priya;Jones,RyanM;Lawrence,MaggieV;Bittles,LeahA;Hill,AmyM;O'Sheal,ShannonE;Armstrong,AndreaW;Thomas,ChristyL;Daniel,LauraH;Tofil,NancyM;Sasser,WilliamC;Richter,RobertP