Mural cell TGF-beta-mediated signaling and neonatal intracerebral hemorrhage

壁细胞TGF-β介导的信号传导与新生儿脑出血

• 批准号: 8772010
• 负责人: Daniel Greif
• 金额: $ 24.98万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8772010
• 关键词: ADAMTS1 gene; Alzheimer' s Disease; Animals; Apolipoprotein E; Apoptosis; Attenuated; Basement membrane; Blood - brain barrier anatomy; Blood Vessels; Blood capillaries; Brain; Brain hemorrhage; CASP5 gene; Capillary Endothelial Cell; Cell physiology; Cells; Cerebral Palsy; Cerebral hemisphere hemorrhage; Coculture Techniques; Cognitive deficits; Collection; Cultured Cells; Data; Development; Disease; Disintegrins; Embryo; Embryonic Development; Endothelial Cells; Extracellular Matrix; Foundations; Gelatinase B; Goals; Growth Factor Overexpression; Growth Factor Receptors; Head; Hemorrhage; Human; Incidence; Investigation; Knockout Mice; Ligands; LoxP-flanked allele; Matrix Metalloproteinases; Mediating; Metalloproteases; Molecular; Morbidity - disease rate; Morphology; Mus; Neonatal; Neuraxis; Neurons; PDGFRB gene; Pathogenesis; Pathway interactions; Pattern; Peptide Hydrolases; Pericytes; Perinatal subependymal hemorrhage; Permeability; Phenotype; Play; Population; Premature Infant; Protein Isoforms; Proteins; Proto-Oncogene Proteins c-sis; Publications; Role; Rupture; Seminal; Signal Pathway; Signal Transduction; Testing; Thalamic structure; Tight Junctions; Tissues; Transforming Growth Factor beta; Transforming Growth Factors; Transgenic Mice; Transgenic Organisms; Translating; Tube; Vascular Endothelial Growth Factors; Ventricular; angiogenesis; base; brain tissue; capillary; fetal; insight; intraventricular hemorrhage; migration; mouse model; mutant; neonatal morbidity; nerve stem cell; novel; novel strategies; novel therapeutics; prevent; public health relevance; receptor; white matter

DESCRIPTION (provided by applicant): Intracerebral hemorrhage (ICH) is a debilitating disease that frequently afflicts premature infants. In this population, ICH most commonly originates in the germinal matrix, a collection of highly vascularized neural precursors located in proximity to the thalamus, and often extends into the ventricles. ICH results from compromise of the blood brain barrier (BBB) which in the mouse embryonic brain is composed of endothelial cells (ECs), basement membrane and mural cells known as pericytes (PCs). The overall goal of our project is to yield key insights into BBB formation and devise novel strategies to reduce the incidence and morbidity of ICH and intraventricular hemorrhage (IVH). Little is known about any signaling pathways in PCs that modulate the BBB and have implications for ICH. PDGFR-¿ null mice lack brain PCs and have increased BBB permeability, but no brain hemorrhage or vessel rupture ensues. Transforming growth factor (TGF)¿1 protein levels are reduced in the germinal matrix compared to other regions of the midgestation human brain, and our preliminary results are the first to suggest that attenuating TGF¿ signaling in PCs in the mouse embryo results in gross hemorrhage in the germinal matrix and thalamus and IVH. Embryos carrying PDGFR-¿-Cre and floxed alleles for the TGF¿-receptor 1 (R1), have a relatively modest reduction in PC number but a markedly aberrant morphology and organization of ECs. In addition, it was recently suggested that neurovascular proteases are important players in germinal matrix hemorrhage, and PC-derived matrix metalloproteinase-9 is implicated as contributing to BBB breakdown in Alzheimer's disease. Our initial results in cultured cells and transgenic embryonic mice indicate that PCs with reduced TGF¿-R1 have increased expression of a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS-1), a secreted matrix metalloproteinase that destabilizes capillary EC tubes. We hypothesize that mural cell TGF¿-R1-mediated signaling plays a key role in the development of an intact BBB and that disruption of this signaling pathway stimulates PC expression of factors (e.g., metalloproteinases) that induce aberrant EC polarization, migration and proliferation, thereby disrupting the BBB and causing ICH. To test this hypothesis, our studies will utilize transgenic mice, co-cultures of human brain PCs and ECs and human brain tissue. We aim to: i) elucidate the effects of TGF¿-R1-induced signaling in PCs on cellular processes in brain PC and EC development that are critical for BBB formation; and ii) determine the roles of metalloproteinases, and specifically ADAMTS1, in mediating the deleterious effects of PCs with reduced TGF¿-R1 on BBB formation and EC function. This R21 provides the foundation for a subsequent R01 application investigating in-depth the molecular mechanisms in PCs, ECs and/or surrounding tissues which underlie ICH. Taken together, our studies promise to yield seminal insights into BBB formation and ICH pathogenesis and suggest novel therapeutic strategies to prevent and treat ICH.

描述（由应用程序提供）：脑内出血（ICH）是一种使人衰弱的疾病，经常遭受早产儿的痛苦。在这个人群中，ICH最常见的是生发基质，这是位于 靠近丘脑，通常延伸到心室。 ICH是由血液脑屏障（BBB）妥协引起的，该障碍是小鼠胚胎大脑中由内皮细胞（ECS），基底膜和被称为周细胞（PCS）的壁细胞组成的。我们项目的总体目标是对BBB形成产生关键见解，并制定新的策略，以减少ICH和脑室内出血（IVH）的发病率和发病率。对于调节BBB并对ICH具有影响的PC中的任何信号通路知之甚少。 PDGFR-null小鼠缺乏脑部PC，并且增加了BBB渗透性，但随后没有脑出血或血管破裂。与中间型人脑的其他区域相比，生长基质的转化生长因子（TGF）»降低了生发基质的蛋白水平，而我们的初步结果是第一个表明小鼠胚胎中PC的TGFS信号传导导致发芽型和丘脑和丘脑的毛血肿大和IV。带有PDGFR -cRE的胚胎和Flox的Tgf¿-受体1（R1）的胚胎具有相对适度的PC数量，但ECS的形态和组织明显异常。此外，最近有人提出，神经血管蛋白酶是生发基质出血中的重要参与者，并且PC衍生的基质金属蛋白酶-9暗示是导致阿尔茨海默氏病BBB分解的原因。我们在培养的细胞和转基因胚胎小鼠中的最初结果表明，降低的TGF� -R1的PC具有与血小板传播蛋白基序（ADAMTS -1）的崩解蛋白和金属蛋白酶的表达，这是一种分泌的基质金属蛋白酶，这是一种破坏毛细管Ecillary Ec Tubes的替代。 We hypothesize that mural cell TGF¿ -R1-mediated signaling plays a key role in the development of an intact BBB and that disruption of this signaling pathway stimulates PC expression of factors (e.g., metalloproteinases) that induce aberrant EC polarization, migration and proliferation, thereby disrupting the BBB and causing ICH.为了检验这一假设，我们的研究将利用转基因小鼠，人脑PC和ECS和人脑组织的共同培养。我们的目的是：i）阐明TGF¿-R1诱导的PC中PC的信号对BBB形成至关重要的脑PC和EC发育中的细胞过程的影响； ii）确定金属蛋白酶，特别是ADAMTS1的作用，在介导PC的有害效应中，TGF¿-R1对BBB形成和EC功能的有害作用。该R21为随后的R01应用提供了基础，该应用深入研究了PC，ECS和/或周围组织中的分子机制。综上所述，我们的研究有望产生对BBB形成和ICH发病机理的第二见解，并提出了预防和治疗ICH的新型治疗策略。