Perioperative high-density lipoproteins and postoperative AKI

项目摘要 该奖项将支持一项前瞻性临床研究和Loren E的职业发展。Smith，MD，PhD.博士 史密斯完成了博士学位的高密度脂蛋白（HDL）分子生物学与博士肖恩戴维森在 辛辛那提大学和范德比尔特大学医学中心的麻醉学住院医师培训 （VUMC），她在2017年被任命为教师。VUMC是一家三级学术医院，以其高度 合作研究环境，卓越的职业发展计划和广泛的核心设施。 在她的T32奖学金博士史密斯和她的导师，博士林顿，比林斯，维克斯，发现了一个 心脏手术患者术前高HDL与阿基降低之间的相关性在她的提议中， 在这项研究中，Smith博士将检验以下假设：较高的围手术期载脂蛋白（apo）A-I浓度和 特异性HDL-微RNA（miRNAs）与术后阿基较少相关（目的1）， 抑制内皮细胞细胞间粘附分子1（ICAM-1）和肾近端 肾小管细胞toll样受体（TLR）2和TLR 4表达与AKI（Aim 2）较少相关，而外源性AKI（Aim 2） 在肾缺血和再灌注（IR）前对小鼠施用HDL减少肾ICAM-1、TLR 2和TLR 4 表达和阿基（目的3）。目标1和2将在一项150例受试者的前瞻性研究中进行测试， 心脏或血管手术。将在整个研究期间纵向收集血液、尿液和临床数据。 围手术期将用ELISA测定ApoA-I浓度;将分离HDL-miRNA， 用RT-PCR测序和定量; HDL抑制ICAM-1、TLR 2和TLR 4的功能能力将 使用TNF-α和缺氧刺激的人内皮和肾近端小管细胞在体外进行测量 分别将研究受试者的HDL特征与其肾小管应激的严重程度进行比较， 通过尿中金属蛋白酶组织抑制剂2、胰岛素样生长因子- 结合蛋白7和肾损伤分子1以及它们的阿基严重程度，用48小时血清定量 使用潜变量回归建模的肌酐相对于基线的变化。在Aim 3研究中， 在肾IR损伤或假手术之前将一定剂量的HDL颗粒给予小鼠，并且HDL颗粒的作用 将对肾损伤的剂量进行量化。在第二个实验中，含有不同miRNA的HDL将被 在肾IR损伤之前施用HDL-miRNA以确定特异性HDL-miRNA对阿基的作用。 通过完成这项研究，Smith博士将获得翻译研究团队管理方面的培训， 体内实验设计来自林顿博士;围手术期临床研究执行和阿基表型分析来自林顿博士 Billings;以及Vickers博士的HDL相关microRNA（miRNA）测序和生物信息学分析。在 这种方式，在这个职业发展奖的支持下，她的导师团队，以及她的机构 环境，史密斯博士将获得必要的技能，建立一个独立的翻译研究 该项目专注于开发新型脂蛋白疗法，以减少术后阿基。

Project Abstract This award will support a prospective clinical study and the career development of Loren E. Smith, MD, PhD. Dr. Smith completed a PhD in high-density lipoprotein (HDL) molecular biology with Dr. Sean Davidson at the University of Cincinnati and residency training in Anesthesiology at Vanderbilt University Medical Center (VUMC), where she was appointed faculty in 2017. VUMC is a tertiary academic hospital renowned for its highly collaborative research environment, exceptional career development programs, and extensive core facilities. During her T32 fellowship Dr. Smith and her mentors, Drs. Linton, Billings, and Vickers, discovered an association between higher preoperative HDL and reduced AKI in cardiac surgery patients. In her proposed study, Dr. Smith will test the hypotheses that higher perioperative concentrations of apolipoprotein (apo) A-I and specific HDL-microRNAs (miRNAs) are associated with less postoperative AKI (Aim 1), that a higher HDL functional capacity to suppress endothelial cell intercellular adhesion molecule 1 (ICAM-1) and renal proximal tubule cell toll-like receptor (TLR) 2 and TLR4 expression is associated with less AKI (Aim 2), and that exogenous HDL administration to mice before renal ischemia and reperfusion (IR) reduces renal ICAM-1, TLR2, and TLR4 expression and AKI (Aim 3). Aims 1 and 2 will be tested in a 150-subject prospective study of patients undergoing cardiac or vascular surgery. Blood, urine, and clinical data will be collected longitudinally throughout the perioperative period. ApoA-I concentration will be determined with an ELISA; HDL-miRNAs will be isolated, sequenced and quantified with RT-PCR; and HDL functional capacity to suppress ICAM-1, TLR2, and TLR4 will be measured in vitro using human endothelial and renal proximal tubule cells stimulated with TNF-α and hypoxia respectively. Study subjects’ HDL characteristics will be compared to their severity of renal tubule stress and damage, quantified by urinary concentrations of tissue inhibitor of metalloproteinase 2, insulin-like growth factor- binding protein 7, and kidney injury molecule 1 and to their severity of AKI, quantified with 48-hour serum creatinine change from baseline using latent variable regression modeling. During Aim 3 studies, threedifferent doses of HDL particles will be administered to mice before renal IR injury or sham surgery, and the effects of HDL dose on renal damage will be quantified. In a second experiment, HDL containing different miRNAs will be administered before renal IR injury to determine the effect of specific HDL-miRNAs on AKI. By completing this study, Dr. Smith will obtain training in the management of a translational research team and in vivo experimental design from Dr. Linton; perioperative clinical study execution and AKI phenotyping from Dr. Billings; and HDL-associated microRNA (miRNA) sequencing and bioinformatics analysis from Dr. Vickers. In this manner, with the support of this career development award, her mentorship team, and her institutional environment, Dr. Smith will obtain the necessary skills to establish an independent translational research program focused on developing novel lipoprotein-based therapies to reduce postoperative AKI.