Dysregulation of MMP-9 in the neurovascular unit

神经血管单元中 MMP-9 的失调

• 批准号: 7433871
• 负责人: Eng H. Lo
• 金额: $ 30.68万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7433871
• 关键词: Adhesions; Angiotensin II; Angiotensins; Anoikis; Anti-Adhesion Agent; Area; Astrocytes; Biological Models; Blood - brain barrier anatomy; Caspase; Cell Adhesion; Cell Adhesion Molecules; Cell Death; Cell Survival; Cells; Cerebral Ischemia; Cerebrum; Cessation of life; Clinical Data; Collagen; Cultured Cells; Data; Edema; Endopeptidases; Endothelial Cells; Endothelium; Exposure to; Extracellular Matrix Degradation; Extracellular Signal Regulated Kinases; Extravasation; Fibronectins; Functional disorder; Gelatinase A; Gelatinase B; Histologic; Homeostasis; Hypoxia; In Vitro; Infarction; Inflammatory; Injury; Intercellular adhesion molecule 1; Ischemia; Knockout Mice; Knowledge; Laboratories; Laminin; Lead; Ligation; Link; MAPK14 gene; MAPK8 gene; MEKs; Maps; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Measurement; Measures; Mediating; Mediator of activation protein; Mitogen-Activated Protein Kinases; Modeling; Mus; Neurons; Numbers; Optics; Outcome; Oxidative Stress; Pathway interactions; Peptide Hydrolases; Perfusion; Permeability; Physiological reperfusion; Principal Investigator; Program Review Group; Protein Overexpression; Proteolysis; RNA Interference; Regulation; Renin; Reperfusion Therapy; Research Priority; Resistance; Role; STAT1 gene; Signal Pathway; Signal Transduction; Simvastatin; Stroke; System; TIMP1 gene; Testing; Transcription Factor AP-1; Treatment Factor; Tumor Necrosis Factor-alpha; Up-Regulation; cytokine; extracellular; fluorescence imaging; human TNF protein; improved; in vivo; inhibitor/antagonist; insight; integrin-linked kinase; mutant; neurovascular unit; novel; programs; receptor; research study; response; transcription factor

In this project, we will investigate the signaling and consequences of matrix metalloproteinase-9 (MMP-9) dysregulation in cells of the neurovascular unit (cerebral endothelial cells, astrocytes, neurons). Our overall hypothesis is that after stroke, oxidative stress and adhesion molecule signaling upregulates MMP-9 that degrades neurovascular matrix. This leads to not only blood-brain barrier leakage, but also disrupts cell-matrix interactions, thus triggering anoikis-like cell death in endothelium, astrocytes, and neurons. Angiotensin II, an inflammatory mediator, amplifies MMP-9. Treatment with statins and anti-adhesion agents downregulate MMP-9. To test this overall hypothesis, we will pursue 3 specific aims. In Aim 1, we will examine signaling pathways that upregulate MMP-9 using in vitro cultures of cerebral endothelial cells, astrocytes, and neurons. Responses to hypoxia/reoxygenation will be compared with responses to intracellular adhesion molecule (ICAM-1) receptor ligation. The roles of MAP kinase, STAT1, AP-1 and NFkB in MMP-9 regulaton will be assessed. In Aim 2, we will test the idea that MMP-9 upregulation triggers anoikis-like death in endothelial cells, astrocytes, and neurons. We will show that proteolytic degradation of extracellular matrix disrupts integrin linked kinase (ILK) and Akt cell survival signaling, thus activating caspase-mediated cell death. Pharmacologic inhibitors, RNA interference, and mutant ceils lacking MMP-9 or overexpressing the endogenous MMP inhibitor TIMP1 will be examined. In Aim 3, we will investigate the effects of modifying factors and therapy on MMP-9 levels in vitro (cell culture) and in vivo (mouse focal cerebral ischemia). Angiotensin II exposure in endothelial cultures and hypertensive renin/angiotensin overexpressing mice will be used to test for MMP-9 upregulation. Simvastatin and anti-ICAM-1 treatments will be tested to reduce MMP-9. In vivo optical and fluorescence imaging will be supported by the Scientific Core to measure changes in MMP activity, BBB permeability, and cerebral perfusion. Recent data from our lab and others established MMP-9 as a key protease that modifies neurovascular homeostasis. These proposed studies should provide novel insight into how MMP-9 becomes dysregulated and contributes to stroke pathophysiology.

在这个项目中，我们将研究神经血管单元细胞（脑内皮细胞、星形胶质细胞、神经元）中基质金属蛋白酶 9 (MMP-9) 失调的信号传导和后果。我们的总体假设是，中风后，氧化应激和粘附分子信号传导上调 MMP-9，从而降解神经血管基质。这不仅会导致血脑屏障渗漏，还会破坏细胞与基质的相互作用，从而引发内皮、星形胶质细胞和神经元中的失巢凋亡样细胞死亡。血管紧张素 II 是一种炎症介质，可放大 MMP-9。他汀类药物和抗粘连剂治疗可下调 MMP-9。为了检验这一总体假设，我们将追求 3 个具体目标。在目标 1 中，我们将使用脑内皮细胞、星形胶质细胞和神经元的体外培养物检查上调 MMP-9 的信号通路。对缺氧/复氧的反应将与对细胞内粘附分子 (ICAM-1) 受体连接的反应进行比较。将评估 MAP 激酶、STAT1、AP-1 和 NFkB 在 MMP-9 调节中的作用。在目标 2 中，我们将测试以下观点：MMP-9 上调会引发内皮细胞、星形胶质细胞和神经元中的失巢凋亡样死亡。我们将证明细胞外基质的蛋白水解降解会破坏整合素连接激酶 (ILK) 和 Akt 细胞生存信号，从而激活 caspase 介导的细胞死亡。将检查药理学抑制剂、RNA 干扰以及缺乏 MMP-9 或过度表达内源性 MMP 抑制剂 TIMP1 的突变细胞。在目标 3 中，我们将研究修饰因素和治疗对体外（细胞培养）和体内（小鼠局灶性脑缺血）MMP-9 水平的影响。内皮培养物和高血压肾素/血管紧张素过表达小鼠中的血管紧张素 II 暴露将用于测试 MMP-9 上调。将测试辛伐他汀和抗 ICAM-1 治疗以减少 MMP-9。 Scientific Core 将支持体内光学和荧光成像，以测量 MMP 活性、BBB 通透性和脑灌注的变化。我们实验室和其他实验室的最新数据表明 MMP-9 是改变神经血管稳态的关键蛋白酶。这些拟议的研究应该为 MMP-9 如何失调以及如何促进中风病理生理学提供新的见解。