Role of MicroRNAs in Ischemic Tolerance

MicroRNA 在缺血耐受中的作用

基本信息

批准号：
7273884
负责人：
JULIE Anne SAUGSTAD
金额：
$ 20.32万
依托单位：
LEGACY EMANUEL HOSPITAL AND HEALTH CENTER
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-08-02 至 2008-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7273884
关键词：
Asthma Brain Brain Ischemia Cell Survival Cells Chromatin Class Code Contralateral DNA Microarray Chip DNA Microarray format Data Development Diabetes Mellitus Disease Down-Regulation Event Gene Expression Genetic Translation Genotype Glucose Goals Hepatitis C Hour Huntington Disease In Vitro Infection Injury Ischemia Ischemic Preconditioning Lead Macular degeneration Malignant Neoplasms Mammalian Cell Messenger RNA MicroRNAs Microarray Analysis Middle Cerebral Artery Occlusion Modeling Molecular Molecular Profiling Mus Northern Blotting Numbers Oxygen Phenotype Polymerase Chain Reaction Proteins RNA RNA Interference Rattus Regulation Research Personnel Role Stroke prevention System Therapeutic Agents Time Transcriptional Activation Translations Up-Regulation base day deprivation in vivo mind control neuroprotection novel novel therapeutics preconditioning programs protein expression research study response

项目摘要

DESCRIPTION (provided by applicant): Ischemic tolerance is a phenomenon whereby a sub-lethal ischemic injury, preconditioning, induces endogenous protective mechanisms that lessen the impact of a subsequent, more severe ischemic insult. We have used modeled ischemic tolerance in rat and mouse, both in vivo and in vitro, to describe multiple effectors of neuroprotection in these endogenous systems. Recently, we used DNA microarray to examine changes in gene expression in mouse brains subjected to preconditioning induced by a brief duration of ischemia, injurious ischemia, or a tolerant brain (preconditioned, then challenged with injurious ischemia). These experiments revealed that injurious ischemia up-regulated gene expression, while ischemic tolerance resulted in significant down-regulation of gene expression. Thus the signature of ischemic tolerance is that of suppressed gene expression. Elucidating the molecular mechanism(s) that underlie this focused transcriptional suppression is our goal. Eukaryotic gene expression is regulated by microRNAs, a newly identified class of small non-protein coding RNAs that regulate mRNA translation and chromatin activity in mammalian cells. Based on the signature of ischemic tolerance, a suppression of gene expression, we hypothesize that ischemic tolerance leads to regulated microRNA expression that in turn leads to the protected phenotype. In support of this hypothesis, our preliminary data show that distinct subsets of microRNAs are regulated in preconditioned, ischemic, and tolerant mouse brain. Thus to fully examine a role for microRNAs in ischemic tolerance, we propose the following specific aims: 1) establish the expression profile of microRNAs in preconditioned, ischemic, and tolerant mouse brain by microarray analysis, 2) confirm changes in, and examine the temporal expression of, microRNAs regulated in preconditioned, ischemic, and tolerant mouse brain, and 3) examine the effect of regulated microRNAs on target protein expression and cell survival. These studies are among the first to examine the regulated expression of miRNAs in response to modeled ischemia, and given the current development of short, interference RNAs as novel therapeutic agents for a number of diseases including macular degeneration, asthma, diabetes, cancer, Huntington's, and Hepatitis C infection, these studies may provide rationale for the development of similar strategies for the treatment or prevention of stroke and brain ischemia.

描述（由申请人提供）：缺血耐受是一种现象，亚致死性缺血性损伤、预处理诱导内源性保护机制，从而减轻随后更严重的缺血性损伤的影响。我们在体内和体外使用大鼠和小鼠的缺血耐受模型来描述这些内源系统中神经保护的多种效应器。最近，我们使用 DNA 微阵列来检查小鼠大脑中基因表达的变化，这些小鼠大脑受到短暂缺血、损伤性缺血或耐受性大脑（预处理，然后受到损伤性缺血的挑战）诱导的预处理。这些实验表明，损伤性缺血会上调基因表达，而缺血耐受性会导致基因表达显着下调。因此，缺血耐受的特征是基因表达受到抑制。阐明这种集中转录抑制的分子机制是我们的目标。真核基因表达受 microRNA 调节，microRNA 是一类新发现的小型非蛋白质编码 RNA，可调节哺乳动物细胞中 mRNA 翻译和染色质活性。基于缺血耐受的特征，即基因表达的抑制，我们假设缺血耐受会导致 microRNA 表达受到调节，进而导致受保护的表型。为了支持这一假设，我们的初步数据表明，不同的 microRNA 子集在预处理、缺血和耐受的小鼠大脑中受到调节。因此，为了充分研究 microRNA 在缺血耐受中的作用，我们提出以下具体目标：1）通过微阵列分析建立预处理、缺血和耐受小鼠大脑中 microRNA 的表达谱，2）确认时间变化并检查预处理、缺血和耐受小鼠大脑中受调节的 microRNA 的表达，3) 检查受调节的 microRNA 对靶蛋白表达和细胞存活的影响。这些研究是首批检查 miRNA 响应模拟缺血的调节表达的研究之一，考虑到目前短干扰 RNA 的发展，作为许多疾病的新型治疗剂，包括黄斑变性、哮喘、糖尿病、癌症、亨廷顿舞蹈症、和丙型肝炎感染，这些研究可能为开发治疗或预防中风和脑缺血的类似策略提供依据。