Functional role and therapeutic targeting of exosomes and extracellular RNA biomarkers in heart failure

尽管在治疗心力衰竭(HF)方面取得了重大进展，但50%的患者在5年内死亡 在他们第一次入院时被诊断为心力衰竭，心力衰竭仍然是发病率、死亡率和 美国的医疗保健支出。预计到2030年，心力衰竭的患病率将增加到46%， 对心力衰竭发病机制的新见解和阻断这一进展的策略是一个巨大的未完成的任务 临床需要。我的研究主要集中在外体或细胞外小泡(Ev)及其货物的作用上。 RNAs(EV-RNAs)作为新的功能生物标记物。我们已经发现并验证了血浆RNA签名 与人类心力衰竭表型相关的基因，如心肌梗死后的不良结构重构， 纤维化和心律失常猝死。我们已经证明，这些血浆RNA中的许多是隔离的 在电动汽车内，是一种新的细胞间通信模式。重要的是，这些EV-RNA中的许多都会发生变化 在心脏组织中，调节复杂的信号通路可能是心力衰竭发病的基础。这 这项工作提供了一个独特的机会来开发i)新的临床有用的生物标志物，以改善风险分层 心力衰竭患者的新治疗靶点；ii)阻断不利重构过程的新治疗靶点。 我现在寻求利用过去5年开发的工具和平台来推动EV和EV-RNA 利用灵活的R35赠款机制，在新的领域开展工作。我试图概括地谈到以下广泛的问题 未得到满足的需求领域。 1.提高血浆的性能(包括预测/预测的准确性和变异系数) 通过更具体地在生物信息库血浆中的验证平台上测量EV-RNA来确定RNA生物标记物 样本来自仔细分型的心力衰竭和心肌梗死后患者。 2.确定从不同表型的人心力衰竭样本中分离的EVS的功能作用 细胞培养(IPSC来源的CMS)和芯片上器官模型 3.利用一种新的外切体追踪小鼠模型(ExoMap)来确定功能 外切体靶向心肌细胞和其他心肌细胞在小鼠心肌缺血模型中的作用 和非缺血型心衰，采用单细胞核RNAseq。 4.确定EV释放/摄取的小分子调节剂，以操纵EV介导的信号转导 小鼠模型。 5.利用新发现的细胞RNA生物标记物开发新的条件siRNA疗法， 靶向心肌肥大、自噬和纤维化。 R35机制提供的灵活性和自由度将使我能够追求这些高风险和高回报 寻求解决该领域关键差距的实验，也将为致力于指导提供时间 下一代心血管疾病研究人员。

Despite important advances in the treatment of heart failure (HF), >50% of patients die within 5 years of diagnosis at their first hospital admission, and HF remains a leading cause of morbidity, mortality and healthcare expenditure in the United States. With the prevalence of HF expected to increase to 46% by 2030, novel mechanistic insight into HF pathogenesis and strategies to interrupt this progression are a large unmet clinical need. My research has focused on the role of exosomes or extracellular vesicles (EVs) and their cargo RNAs (EV-RNAs) as novel functional biomarkers. We have discovered and validated plasma RNA signatures that correlate with human HF phenotypes such as adverse structural remodeling after myocardial infarction, fibrosis and sudden arrhythmic death. We have shown that many of these plasma RNAs are sequestered within EVs and are a novel mode of intercellular communication. Importantly, many of these EV-RNAs change in parallel in cardiac tissue, modulating complex signaling pathways that may underlie HF pathogenesis. This work affords a unique opportunity to develop i) novel clinically useful biomarkers for improved risk stratification of HF patients; and ii) novel therapeutic targets to interrupt the adverse remodeling process. I now seek to leverage the tools and platforms developed over the past 5 years to move the EV and EV-RNA field in new directions using the flexible R35 grant mechanism. I seek to broadly address the following broad areas of unmet need. 1. Improve the performance (including prognostic/predictive accuracy and coefficient of variance) of plasma RNA biomarkers by more specifically measuring EV-RNAs on validated platforms in biorepository plasma samples from carefully-phenotyped HF and post-MI patients. 2. Determine a functional role for EVs isolated from human HF samples with varied phenotypes in simplified cell culture (iPSC-derived CMs) and organ-on-chip models 3. Leverage a novel murine model of exosome tracking (ExoMap) mouse to determine the functional consequences of exosome targeting in cardiomyocytes and other cardiac cells in murine models of ischemic and non-ischemic HF using single cell nuclear RNAseq. 4. Identify small molecule regulators of EV release/uptake to manipulate EV-mediated signaling in these murine models. 5. Leverage newly identified cellular RNA biomarkers to develop novel conditional siRNA therapeutics that target cardiac hypertrophy, autophagy and fibrosis. The flexibility and latitude afforded by the R35 mechanism will allow me to pursue these high-risk high-reward experiments that seek to address critical gaps in this field and will also provide time for devoting to mentoring of the next generation of cardiovascular disease investigators.