Regulatory microRNAs-mediated cerebrovascular protection and traumatic braininjury

调节性 microRNA 介导的脑血管保护和创伤性脑损伤

• 批准号: 10478480
• 负责人: Kejie Yin
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2026-09-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10478480
• 关键词: American; Attenuated; Binding; Biological Markers; Biological Process; Blood - brain barrier anatomy; Blood Vessels; Blood brain barrier dysfunction; Brain; Brain Injuries; Cardiovascular system; Cells; Cerebrovascular system; Cerebrum; Cognitive deficits; Dose; Edema; Endothelial Cells; Endothelium; European; Event; Extravasation; Functional disorder; Genetic; Hemorrhage; Human; Human Resources; Immune; Impairment; Individual; Inflammation; Inflammatory Response; Injury; Intravenous; Ischemic Brain Injury; Mediating; Medical; MicroRNAs; Molecular; Mus; Myocardial Infarction; Myocardial Ischemia; Nervous System Trauma; Neurologic Deficit; Neurological outcome; Neurons; Outcome; Pathogenesis; Pathologic; Peripheral; Permeability; Pharmaceutical Preparations; Pharmacologic Substance; Pharmacotherapy; Plasma; Play; Proteins; Regulation; Rodent; Role; Secondary to; Services; TBI treatment; Testing; Tight Junctions; Time; Translations; Traumatic Brain Injury; Untranslated RNA; Untranslated Regions; Veterans; blood-brain barrier disruption; brain endothelial cell; carcinogenesis; cerebral microvasculature; cerebrovascular; clinical diagnosis; clinical prognosis; effective therapy; immune cell infiltrate; improved; inhibitor; long term recovery; microRNA delivery; migration; military veteran; nervous system disorder; neurobehavioral; neuron loss; novel; post-trauma; posttranscriptional; prevent; protein expression; therapeutically effective; white matter; white matter injury

Traumatic brain injury (TBI) is a major medical concern in service personnel and veterans as currently no therapy is available to alleviate post-trauma neurological deficits. The blood-brain barrier (BBB) provides a dynamic interface to separate the brain from the circulatory system, maintaining a stable brain microenvironment. As a major component of the BBB, brain microvascular endothelial cells (BMECs), together with intercellular tight junctions (TJs), play a dominant role in modulating BBB integrity and paracellular permeability1. Accumulating evidence has demonstrated that BBB breakdown after TBI promotes a devastating cascade of events such as transmigration of peripheral immune cells, cerebral inflammatory responses, edema, and hemorrhagic transformation, contributing to secondary injury in neurotrauma. Thus, it is necessary to identify mechanisms and develop effective therapeutic strategies that protect BBB integrity and prevent permanent brain damage after TBI. MicroRNAs (miRs) function as a major class of small non-coding RNAs that negatively modulate protein expression. In addition to their critical role in various biological processes, miRs have also been implicated in a variety of human neurological diseases. We and others have shown the involvement of miRs in the pathogenesis of TBI. However, the functional significance and molecular mechanisms of miR molecules in regulating cerebrovascular pathogenesis, in particular BBB disruption/dysfunction, and resultant long-term neurological outcomes are poorly understood in TBI. The miR-15a/16-1 cluster is the first identified miR group associated with human carcinogenesis. Dysregulated plasma miR-15a/16-1 levels have been found in TBI individuals, showing great potential as useful biomarkers in clinical diagnosis and prognosis. Interestingly, molecular inhibition of miR-15a/16-1 levels has been shown to protect against myocardial infarction (MI) and ischemic brain injury. Therefore, American and European pharmaceutical companies consider the miR-15a/16-1 cluster as one of the most important miR targets to develop miR-based drugs for the treatment of MI. In our recent preliminary studies, we have shown that expression of the miR-15a/16-1 cluster is selectively increased in the mouse cerebral vasculature after TBI. Of note, endothelial cell (EC)-selective miR- 15a/16-1 genetic deficiency leads to reduced BBB leakage, and less neuronal loss, white matter (WM) injury, and neurobehavioral impairments in mice after TBI. We also found that the miR-15a/16-1 cluster can bind to the 3’-UTRs of major BBB tight junctions, brain-enriched Claudins, and inhibit their translation, and genetic silencing or deletion of the miR-15a/16-1 cluster significantly increased endothelial or cerebral expression of claudins. These findings have provided the basis for our Central Hypothesis that genetic deletion of vascular miR-15a/16-1 attenuates BBB disruption and subsequent pathological cascades after TBI, thereby contributing to increased BBB stabilization, reduced neuronal/WM loss, and improved long- term neurological outcomes in TBI. Three aims will be performed in this proposal. Aim 1: Define the role of vascular miR-15a/16-1 in post-traumatic BBB dysfunction and TBI outcomes; Aim 2: Elucidate the mechanisms of miR-15a/16-1 regulation of post-traumatic BBB dysfunction; Aim 3: Explore systematic delivery of miR- 15a/16-1 antagomir (inhibitor) as a potential therapy in TBI through BBB stabilization. Elucidating the molecular mechanisms of miR-15a/16-1-mediated BBB dysfunction may lead us to discover novel and effective treatment against TBI.

创伤性脑损伤 (TBI) 是现役军人和退伍军人的一个主要医疗问题，因为目前还没有 治疗可缓解创伤后神经功能障碍。血脑屏障（BBB）提供了一种治疗方法。 动态界面将大脑与循环系统分离，保持大脑稳定 脑微血管内皮细胞（BMEC）作为血脑屏障的主要组成部分。 与细胞间紧密连接 (TJ) 结合，在调节 BBB 完整性和细胞旁细胞中发挥主导作用 越来越多的证据表明，TBI 后 BBB 的破坏会导致毁灭性的后果。 一系列事件，例如外周免疫细胞的迁移、脑炎症反应、水肿、 和出血性转化，导致神经外伤的继发性损伤。 确定机制并制定有效的治疗策略，保护 BBB 完整性并预防 TBI 后造成永久性脑损伤。 MicroRNA (miR) 是一类主要的小非编码 RNA，可负向调节蛋白质 miR 除了在各种生物过程中发挥关键作用外，还与多种生物学过程有关。 我们和其他人已经证明 miR 参与了多种人类神经系统疾病。 然而，miR 分子在 TBI 发病机制中的功能意义和分子机制。 调节脑血管发病机制，特别是血脑屏障破坏/功能障碍，以及由此产生的长期 对 TBI 的神经系统结果知之甚少。 miR-15a/16-1簇是第一个确定的与人类致癌相关的miR组。 在 TBI 个体中发现血浆 miR-15a/16-1 水平失调，显示出巨大的潜力 在临床诊断和预后中有用的生物标志物。 已被证明可以预防心肌梗塞（MI）和缺血性脑损伤，因此，美国。 欧洲制药公司认为 miR-15a/16-1 簇是最重要的 miR 之一 目标是开发基于 miR 的药物来治疗 MI。 在我们最近的初步研究中，我们发现 miR-15a/16-1 簇的表达是 值得注意的是，TBI 后小鼠脑血管系统中内皮细胞 (EC) 选择性 miR- 选择性增加。 15a/16-1 遗传缺陷导致 BBB 渗漏减少、神经元损失、白质 (WM) 损伤、 我们还发现 miR-15a/16-1 簇可以与 TBI 后的小鼠神经行为损伤结合。 主要 BBB 紧密连接的 3'-UTR、大脑富集的 Claudins 并抑制其翻译，以及遗传 miR-15a/16-1簇的沉默或缺失显着增加内皮或大脑的表达 这些发现为我们的中心假设提供了基础，即基因缺失。 血管 miR-15a/16-1 减弱 BBB 破坏和 TBI 后随后的病理级联反应， 有助于增加 BBB 稳定性，减少神经/WM 损失，从而改善长期 本提案将实现三个目标：定义 TBI 的作用。 血管 miR-15a/16-1 在创伤后 BBB 功能障碍和 TBI 结局中的作用 目标 2：阐明机制； miR-15a/16-1 对创伤后 BBB 功能障碍的调节；目标 3：探索 miR-15a/16-1 的系统传递 15a/16-1 antagomir（抑制剂）通过阐明 BBB 稳定作用作为 TBI 的潜在疗法。 miR-15a/16-1介导的BBB功能障碍的机制可能会引导我们发现新的有效的治疗方法 对抗 TBI。