Protecting the kidney and remote organs following renal ischemia

肾脏和其他器官的缺血性损伤是致命的，代价也很高。缺血性急性肾损伤 (AKI)发生在多达三分之二的重症监护患者和五分之一的住院成年人中，约170万人 这些病人每年都会死亡。然而，AKI中非常高的死亡率并不是由肾功能衰竭本身引起的。 流行病学和临床数据支持AKI相关的远端器官功能障碍在穷人中的关键作用 急性心肌梗死患者的预后和死亡率。AKI还可导致慢性肾脏疾病(CKD)，CKD进展为 终末期肾病(ESRD)和肾移植失败。虽然AKI和CKD是繁重的，但过渡 ESRD可能特别危险；退伍军人的死亡率(~40%)在#年的前90天是巨大的 ESRD护理。AKI目前没有治疗方法；因此，有效的AKI治疗是一个重要的未得到满足的医疗需求。 对肾缺血的强烈、迅速的炎症和氧化应激反应一直很好。 由其他人和我们记录的。肾缺血后，远隔器官也出现炎症， 但受损的肾脏和遥远的器官之间的“串音”也没有被很好地理解。功成名就 回顾资金，我们已经证明了基于成人细胞的疗法在多种模型中的有效性 肾功能衰竭。考虑到相对较少的细胞的巨大好处，我们假设细胞外小泡(EV或 从移植细胞中释放出来的非病毒生物(Exosome)是治疗效应。我们发现 肾脏EV比原始细胞更有效，减少炎症和氧化应激， 改善缺血后的肾功能，即使在肾功能衰竭确诊后给予。其他人则有 在肾损伤模型中显示了EV的益处。我们现在建议给抗炎和抗氧化下定义- 蚂蚁对肾脏EV在肾脏和远处器官的影响，并确定其具体的治疗货色。 我们的长期目标是开发有效的治疗方法，以改善退伍军人的预后 肾脏的侮辱。我们在这项提案中的目标是定义主要的利益介体(包括抗炎 和抗氧化分子)在肾脏和遥远的器官中被EV改善，并决定 电动汽车货物中的“活性成分”。我们的中心假设是肾脏EV提供了一种多方面的治疗方法 肾脏缺血性损伤，肾脏超氧化物歧化酶和过氧化氢酶升高，抗炎细胞因子和皮肤 而血小板EV并不能减轻炎症，也没有保护作用。这将使我们能够定义特定的 肾脏电动汽车中的有益货物。我们将利用强大的空间转录技术来研究 缺血时的变化和EV的改善。此外，我们假设全身和远程器官 炎症是由缺血引起的，而不是尿毒症，EV可以改善炎症。根据我们的初步调查 数据，我们提出以下目标，以填补肾脏损伤和保护机制方面的知识空白： 1.明确不同来源的细胞外囊泡对缺血后肾功能的影响。 炎症和氧化应激。初步数据支持肾脏的疗效，但不支持血小板或皮肤EV的疗效。 我们将研究提高疗效的方法(包括缺血预适应)。我们还将比较 有益和无效EV对大鼠肾脏缺血损伤通路的影响 以确定肾脏损伤的基本治疗物质成分和最易改变的途径。 2.确定肾缺血对远隔器官炎症和氧化应激的影响 EV对肾缺血后炎症反应和器官功能的影响。 在这项工作的结论中，我们预计已经定义了关键的炎症和氧化应激 缺血性肾损伤的介质，肾脏缺血对远处器官炎症的影响，其他 有益于缺血后和改善炎症和肾功能的EV货物的特定机制。 预计结果将产生重大的积极影响，因为它们将提供强有力的证据- 基于进一步开发潜在疗法以改善AKI结果的原则证据。

Ischemic injury to the kidney and other organs is deadly and expensive. Ischemic acute kidney injury (AKI) occurs in up to two thirds of intensive care patients and 1 in 5 hospitalized adults with ~1.7 million of these patients dying annually. The very high mortality in AKI, however, is NOT caused by renal failure per se. Epidemiological and clinical data support the critical role of AKI-associated distant organ dysfunction in poor outcomes and mortality in AKI. AKI also can result in chronic kidney disease (CKD), progression of CKD to end stage renal disease (ESRD) and kidney transplant failure. While AKI and CKD are onerous, the transition to ESRD can be particularly perilous; mortality rates in Veterans (~40%) are huge in the first 90 days of ESRD care. AKI has no current treatment; thus, effective AKI therapy is an important unmet medical need. The robust, prompt inflammatory and oxidative stress response to renal ischemia has been well documented by others and by us. Inflammation in remote organs has also been found after renal ischemia, but the “crosstalk” between the injured kidney and remote organs is also not well understood. With Merit Review funding, we have demonstrated the effectiveness of adult-cell based therapies in multiple models of renal failure. Given the large benefits of relatively few cells, we hypothesized that extracellular vesicles (EV or exosomes), a non-viral biologic, released from the transplanted cells were the therapeutic effector. We found that renal EV were more effective than the originating cells, decreasing inflammation and oxidative stress and improving renal function postischemia, even when given after renal failure was established. Others have shown benefit with EV in renal injury models. We now propose to define the anti-inflammatory and anti-oxid- ant effects of renal EV in the kidney and remote organs and determine the specific therapeutic cargo. Our long-term goal is the development of effective therapies to improve outcomes in Veterans with renal insults. Our objective in this proposal is defining key mediators of benefit (including anti-inflammatory and anti-oxidative molecules) in the kidney and remote organs that are improved by EV and determine the “active ingredients” in EV cargo. Our central hypotheses are that renal EV provide a multi-faceted therapy for renal ischemic injury, increasing renal superoxide and catalase and anti-inflammatory cytokines and that skin and platelet EV do not decrease inflammation and are not protective. This will allow us to define the specific beneficial cargo in renal EV. We will employ the powerful technique of spatial transcriptomics to examine the changes with ischemia and improvements with EV. Furthermore, we posit that systemic and remote organ inflammation result from ischemia and not uremia and can be improved with EV. Based on our preliminary data, we propose the following aims to fill knowledge gaps in the mechanisms of renal injury and protection: 1. To define the efficacy of extracellular vesicles from different sources on postischemic renal function, inflammation and oxidative stress. Preliminary data support efficacy of renal, but not platelet or skin EV. We will examine means (including ischemic preconditioning) to improve efficacy. We will also compare cargo and the effects on pathways of ischemic injury between beneficial renal EV and ineffective EV in order to define the essential therapeutic cargo components and most altered pathways of renal injury. 2. To determine the effect of renal ischemia on inflammation and oxidative stress in remote organs and the effect of EV on inflammation and organ function following renal ischemia. At the conclusion of this work, we expect to have defined the key inflammatory and oxidative stress mediators of ischemic renal injury, the effects of renal ischemia on inflammation in remote organs, other specific mechanisms of benefit postischemia and the EV cargo that improve inflammation and renal function. The results are expected to have a significant positive impact in that they will provide the strong evidence- based proof of principle for further development of potential therapies to improve outcomes in AKI.