Kruppel-like factor 11 and ischemic stroke

Kruppel 样因子 11 与缺血性中风

基本信息

批准号：
9243321
负责人：
Kejie Yin
金额：
$ 33.4万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-11-11 至 2020-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9243321
关键词：
Acute Adenoviruses Adhesions Adult Agonist Astrocytes Attenuated Basement membrane Binding Sites Blood Blood - brain barrier anatomy Blood Vessels Brain Brain Infarction Brain Injuries Capillary Endothelial Cell Cardiovascular system Cause of Death Cell Death Cerebral Ischemia Cerebrovascular system Cerebrum Coculture Techniques Development Diabetes Mellitus Diabetic mouse Differentiation and Growth Edema Event Exposure to Extracellular Matrix Extravasation Family Family member Functional disorder Genes Genetic Genetic Transcription Glucose Hemorrhage Human Hyperglycemia In Vitro Inflammation Inflammatory Inflammatory Response Ischemia Ischemic Stroke Kruppel-like transcription factors Lead Leukocytes Mediating Mediator of activation protein Messenger RNA Middle Cerebral Artery Occlusion Modeling Molecular Mus Mutation Neurological outcome Neuronal Dysfunction Neurons Neutrophil Infiltration Non-Insulin-Dependent Diabetes Mellitus Oxygen PPAR gamma Pathogenesis Pathologic Pathology Pericytes Permeability Peroxisome Proliferator-Activated Receptors Pharmacologic Substance Play Process Promoter Regions Property Receptor Signaling Recruitment Activity Regulation Reporting Risk Factors Role Signal Transduction Stimulus Stroke Testing Therapeutic Intervention Thrombolytic Therapy Tight Junctions Time Transgenic Mice United States Vascular Endothelium Zinc Fingers brain endothelial cell cell growth cell water cerebrovascular deprivation disability effective therapy foot in vivo member neuron loss non-diabetic novel public health relevance transcription factor vasogenic edema

项目摘要

DESCRIPTION (provided by applicant): The blood-brain barrier (BBB) damage and dysfunction is well-recognized as a major hallmark of ischemic stroke. As a major component of the BBB, brain microvascular endothelial cells (BMECs), together with the tight junctions (TJs) between BMECs, play a dominant role in modulating BBB integrity and paracellular permeability. Extensive studies have shown that breakdown of the BBB contributes to cerebral inflammatory responses, edema, hemorrhagic transformation, and eventual neuronal loss in cerebral ischemia. Thus, it is important to identify mechanisms by which BBB integrity and function can be compromised in ischemic stroke. Krüppel-like factors (KLFs) are members of the zinc finger family of transcription factors and consist of 17 members that have been shown to play key roles in cellular growth and differentiation. Recent studies have documented that KLFs are implicated in developmental and pathological vascular processes. However, the function of the KLF family in the cerebral vasculature is largely unexplored. KLF11 is a unique diabetes- associated KLF transcription factor among 17 KLF family members and highly expresses in vascular endothelium. Mutations in the KLF11 gene result in Maturity Onset Diabetes of the Young 7 (MODY7), and are closely associated with human type 2 diabetes mellitus, a major risk factor for stroke. Previously, we reported that peroxisome proliferator-activated receptor γ-mediated cerebral vascular protection during ischemic insults needs recruitment of KLF11 as its critical co-activator. However, the functional significance and mechanisms of KLF11 itself in regulating cerebrovascular pathogenesis are totally unknown in ischemic stroke. In our recent preliminary studies, we have shown that KLF11 expression is significantly decreased in the cerebral vasculature, and also in cultured BMECs after in vivo and in vitro ischemic stimuli. Of note, EC- selective KLF11 transgenic mice display reduced BBB leakage in ischemic brains, whereas KLF11 genetic deficiency results in increased BBB permeability and larger brain infarction in mice after middle cerebral artery occlusion (MCAO). Mechanistically, we found several potential KLF11 binding sites in the promoter region of selective endothelial tight junctions, and genetic deletion of KLF11 in mice significantly reduced cerebral expression of Claudin 5 and ZO-1 mRNAs as well as increased leukocyte-endothelial rolling and adhesion in the vascular wall. Moreover, we also demonstrated that gain-of-KLF11 function by adenovirus can significantly inhibit BMEC death after exposure to Oxygen Glucose Deprivation (OGD). These findings have provided the basis for our Central Hypothesis that endothelial KLF11 functions as a novel BBB stabilizer and its reduction contributes to BBB dysfunction and brain injury after ischemic stroke. Three aims will be performed in this proposal. Aim 1: Define the role of KLF11 in BBB dysfunction and brain injury after ischemic stroke; Aim 2: Define the molecular mechanisms of KLF11 in regulating ischemia-induced BBB dysfunction; Aim 3: Define if activation of KLF11 by upstream signaling regulates post-ischemic BBB dysfunction.

描述（申请人提供）：血脑屏障（BBB）损伤和功能障碍被公认为缺血性中风的主要标志，脑微血管内皮细胞（BMEC）作为BBB的主要组成部分。 BMEC 之间的紧密连接 (TJ) 在调节 BBB 完整性和细胞旁通透性方面发挥着主导作用，大量研究表明 BBB 的破坏会导致脑炎症。因此，确定锌指家族成员 Krüppel 样因子 (KLF) 在缺血性中风中损害 BBB 完整性和功能的机制非常重要。转录因子由 17 个成员组成，已被证明在细胞生长和分化中发挥关键作用。最近的研究表明，KLF 与发育和病理性血管过程有关。脑血管系统中的 KLF 家族在 17 个 KLF 家族成员中是一种独特的与糖尿病相关的 KLF 转录因子，在血管内皮中高度表达，KLF11 基因突变导致青年型糖尿病 7 (MODY7)。，并且与人类2型糖尿病（中风的主要危险因素）密切相关。缺血性损伤期间增殖剂激活受体γ介导的脑血管保护需要招募KLF11作为其关键的共激活剂，然而，在我们最近的初步研究中，KLF11本身在调节脑血管发病机制中的功能意义和机制尚不清楚。值得注意的是，在体内和体外缺血刺激后，脑血管系统以及培养的 BMEC 中的 KLF11 表达显着降低。 EC选择性KLF11转基因小鼠在缺血性大脑中表现出血脑屏障渗漏减少，而KLF11遗传缺陷导致大脑中动脉闭塞（MCAO）后小鼠的血脑屏障通透性增加和更大的脑梗死。从机制上讲，我们在启动子中发现了几个潜在的KLF11结合位点。选择性内皮紧密连接区域和小鼠 KLF11 基因缺失显着降低了 Claudin 5 和 ZO-1 mRNA 的大脑表达以及此外，我们还证明，腺病毒获得的 KLF11 功能可以显着抑制缺氧葡萄糖 (OGD) 后的 BMEC 死亡。这些发现为我们的中心研究提供了基础。假设内皮 KLF11 作为一种新型 BBB 稳定剂，其减少会导致缺血性中风后 BBB 功能障碍和脑损伤。本研究将实现三个目标。目标 1：确定 KLF11 在缺血性中风后 BBB 功能障碍和脑损伤中的作用；目标 2：确定 KLF11 在调节缺血引起的 BBB 功能障碍中的分子机制；目标 3：确定 KLF11 的激活是否通过上游信号调节。 -缺血性血脑屏障功能障碍。