Role of the human gut microbiome in modulating age-associated aortic stiffening.

项目总结/摘要 此F31应用程序的目的是为先生提供支持。内森格林伯格，一个三年级的毕业生 在科罗拉多大学博尔德分校道格拉斯西尔斯博士（赞助商）实验室的学生（一年级博士生）， 进行研究和培训，使他成为该领域的独立调查员。 转化性心血管（CV）衰老研究，旨在预防和治疗年龄相关CV 疾病（CVD）。他计划完善目前正在开发的研究技能，并学习各种新的 技术，概念和专业技能，包括与人类生物标本，使用药理学， 培养的主动脉环的解剖方法，进行生化测定，并掌握测量 在体主动脉脉搏波速度。肠道微生物组组成随着CVD和衰老而独特地改变， 随后循环环境的肠源性变化与CVD有关。然而，无论这些年龄- 导致主动脉僵硬度增加的相关变化尚不清楚。因此，拟议的研究项目旨在 建立人类肠道微生物组作为年龄相关主动脉硬化的关键调节剂。以强为导 初步数据，格林伯格先生将确定，使用创新的“人源化”小鼠模型： 目的1：如果人类肠道微生物组中与年龄相关的变化直接增加主动脉僵硬度， 通过：i）增加循环脂多糖（LPS）和鞭毛蛋白，细菌细胞壁的2种关键成分 ii）激活循环免疫和/或血管细胞中的toll样受体; iii） 增加的主动脉炎症和氧化应激; iv）增加的晚期糖基化终产物的形成; 目的2：如果循环血液中的肠源性“因子”改变了主动脉固有机械刚度， （“循环环境”）通过将切除的主动脉环暴露于来自“人源化”小鼠的血浆; 目的3：老年人肠道微生物组引起循环环境变化的机制 vs.年轻人使用创新的“药物解剖”方法直接增加主动脉僵硬度。 这项研究将是第一个调查衰老人类肠道微生物组的因果作用， 微生物群来源的循环环境介导动脉硬化。如果成功，这项工作将建立 人类肠道微生物组作为治疗/预防年龄相关动脉硬化的治疗靶点。 总体而言，拟议的研究有可能解决两个重要的NHLBI战略愿景研究 优先事项：1）研究对CVD发病重要的新病理生物学机制; 2）确定新的 预防和治疗CVD的治疗靶点。Seals博士是国际公认的NIH资助的 在转化CV研究（特别是“血管”）方面具有成功指导历史的科学家 老化”。在他的监督下，并在专家共同导师维也纳布伦特博士和蒂芙尼威尔的指导下， 先生格林伯格将能够成功地完成拟议的研究和培训计划，促进他的 正在进行的发展，成为一个独立的研究人员在翻译CV老化研究。

PROJECT SUMMARY/ABSTRACT The purpose of this F31 application is to provide support for Mr. Nathan Greenberg, a 3rd year graduate student (1st year PhD student) in Dr. Douglas Seals’ (sponsor) laboratory at the University of Colorado Boulder, to conduct research and training that will prepare him to become an independent investigator in the field of translational cardiovascular (CV) aging research aimed at the prevention and treatment of age-related CV diseases (CVD). He plans to refine research skills currently under development and learn a variety of new technical, conceptual, and professional skills including working with human biospecimens, using pharmaco- dissection approaches in cultured aortic rings, conducting biochemical assays, and mastering measurement of in vivo aortic pulse wave velocity. Gut microbiome composition is uniquely altered with CVD and aging, and consequent gut-derived changes to the circulating milieu are related to CVD. However, whether these age- related changes causally increase aortic stiffness is unknown. Thus, the proposed research project seeks to establish the human gut microbiome as a key modulator of age-related aortic stiffening. Guided by strong preliminary data, Mr. Greenberg will determine, using innovative “humanized” mouse models: Aim 1: If age-related changes in the human gut microbiome directly increase aortic stiffness, accompanied by: i) increases in circulating lipopolysaccharide (LPS) and flagellin, 2 key components of bacterial cell walls that can enter circulation; ii) activation of toll-like receptors in circulating immune and/or vascular cells; iii) increased aortic inflammation and oxidative stress; iv) increased formation of advanced glycation end products; Aim 2: If aortic intrinsic mechanical stiffness is altered by the gut-derived “factors” in the circulating blood (“circulating milieu”) by exposing excised aorta rings to plasma from “humanized” mice; Aim 3: The mechanisms by which changes in the circulating milieu induced by the gut microbiome of older vs. young humans directly increases aortic stiffness using innovative “pharmaco-dissection” approaches. This research will be the first to investigate a causal role of the aging human gut microbiome and microbiome-derived circulating milieu in mediating arterial stiffening. If successful, this work will establish the human gut microbiome as a therapeutic target for treatment/prevention of age-related arterial stiffening. Overall, the proposed research has the potential to address two important NHLBI Strategic Vision research priorities: 1) investigate new pathobiological mechanisms important to the onset of CVD; and 2) identify novel therapeutic targets to prevent and treat CVD. Dr. Seals is an internationally recognized and NIH-funded scientist with a strong history of successful mentoring in translational CV research, particularly in “vascular aging”. Under his supervision and with the guidance of expert co-mentors Drs. Vienna Brunt, and Tiffany Weir, Mr. Greenberg will be able to successfully complete the proposed research and training plan, facilitating his ongoing development towards becoming an independent investigator in translational CV aging research.