Interrogating the Potential of Ccn1+ Astrocyte Niches to Drive Angiogenesis after Spinal Cord Injury

探讨 Ccn1 星形胶质细胞生态位在脊髓损伤后驱动血管生成的潜力

• 批准号: 10607960
• 负责人: Keshav Balaji Suresh
• 金额: $ 4.04万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2025-10-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10607960
• 关键词: Address; Adhesions; Astrocytes; Automobile Driving; Axon; Behavioral; Behavioral Assay; Biological Process; Blood - brain barrier anatomy; Blood Vessels; Blood flow; Brain; Cell Proliferation; Cells; Central Nervous System; Characteristics; Complement; Data; Data Set; Development; Dimensions; Distal; Dryness; Endothelial Cells; Endothelium; Environment; Evaluation; Evolution; Family member; Gene Expression; Genes; Genetic Transcription; Goals; Health; Histologic; Histology; Homeostasis; Hybrids; Hypoxia; ITGB3 gene; In Vitro; Injury; Integrins; Ischemia; Knockout Mice; Lateral; Lesion; Life; Ligation; Link; Literature; Location; Locomotor Recovery; Maintenance; Mediating; Methods; Modeling; Molecular; Molecular Evolution; Morphology; Mus; Nervous System Physiology; Neurons; Paralysed; Pathology; Pericytes; Persons; Phenotype; Physiological; Positioning Attribute; Process; Proliferating; Recovery; Recovery of Function; Regenerative capacity; Regulation; Research; Research Personnel; Research Training; Resources; Role; Signal Transduction; Site; Specific qualifier value; Spinal; Spinal Cord; Spinal cord injury; Stroke; Technology; Testing; Therapeutic; Tissues; Training; Transgenic Mice; Up-Regulation; Urination; Vascular remodeling; Vertebral column; Walking; Work; angiogenesis; axon regeneration; axonal sprouting; blood-brain barrier function; career; central nervous system injury; conditional knockout; daily functioning; design; grasp; high dimensionality; in silico; in vivo; innovation; loss of function; motor recovery; mouse model; nervous system disorder; notch protein; novel; novel therapeutics; permissiveness; programs; regeneration potential; regenerative; restoration; spatiotemporal; timeline; transcriptomics; translational neuroscience; white matter

ABSTRACT Spinal Cord Injury (SCI) is a devastating neurological disorder, characterized by disruption to ascending and descending axonal networks, that can leave people paralyzed for life. After SCI, axons in spared white matter (WM) regions attempt to undergo short-range sprouting to restore normal neurological function. However, neuron-extrinsic factors that govern this short-range axon sprouting remain poorly understood. During development and after injury, new axons spatiotemporally follow new blood vessels, hence intimately linking axon sprouting to vasculature. Central Nervous System (CNS) vasculature is orchestrated by astrocytes, which physically interact with endothelia and pericytes to form the gliovascular unit- a tissue niche with indispensable roles in modulating blood flow and Blood Brain Barrier (BBB) maintenance. Astrocytes are also chief responders to any CNS insult and undergo highly context dependent changes in morphology, gene expression, and function in a process collectively referred to as “astrocyte reactivity”. Recent work in stroke and hypoxia have uncovered necessary roles for reactive astrocytes in restorative angiogenesis, but specific astrocyte-secreted molecules mediating these effects remain an outstanding question. I have recently identified a novel, spatially restricted subpopulation of reactive astrocytes defined by persistent upregulation of the powerful pro-angiogenic molecule CCN Family Member 1(CCN1). In my proposal I will utilize two independent, yet complimentary, aims to test the hypothesis that Ccn1+ astrocytes demarcate an evolving pro-angiogenic tissue niche, that promotes functional recovery after SCI by directly governing endothelial cell phenotype including cell proliferation, maturation, or Notch signaling. In Aim 1 I will analyze a first of its kind longitudinal Spatial Transcriptomics dataset of spared tissue regions in a mouse hemisection model of SCI (mhSCI) to A) interrogate the molecular evolution of intraspinal tissue niches harboring Ccn1+ astrocytes, and B) establish a powerful resource for the SCI field. From this aim I will understand the unique molecular features of Ccn1+ astrocyte niches and computationally infer the evolution of associated biological processes, signaling cascades, and transcriptional regulators. In Aim 2 I will complement the computational data from Aim 1 by utilizing a newly generated astrocyte specific CCN1 knockout mouse for A) behavioral assays of locomotor recovery and B) histological assessment of endothelial cell phenotype after mhSCI. From this aim I will interrogate the therapeutic potential of CCN1 for SCI and the direct effect it has on endothelial cell specification. Taken together, this study will uncover the angiogenic potential of tissue niches harboring Ccn1+ astrocytes and start to provide a glimpse into a potential mechanism of action. Such findings may have important implications in the development of new therapeutics that are aimed at providing a more permissive environment for regenerative axon sprouting after SCI.

摘要 脊髓损伤（SCI）是一种破坏性的神经系统疾病，其特征是上行和下行神经系统的中断。 下行轴突网络，这可能会使人终身瘫痪。脊髓损伤后，轴突在备用白色物质 (WM)区域试图经历短程发芽以恢复正常的神经功能。然而，在这方面， 控制这种短程轴突发芽的神经元外在因素仍然知之甚少。期间 在发育和损伤后，新的轴突在时空上跟随新的血管，因此密切地连接 轴突发芽到脉管系统。中枢神经系统（CNS）脉管系统由星形胶质细胞协调， 与内皮细胞和周细胞物理相互作用，形成胶质血管单位-一个具有不可或缺的 在调节血流和维持血脑屏障（BBB）中的作用。星形胶质细胞也是 并在形态学、基因表达和功能上经历高度环境依赖性变化 这一过程统称为“星形胶质细胞反应性”。最近对中风和缺氧的研究发现， 反应性星形胶质细胞在恢复性血管生成中的必要作用，但特异性星形胶质细胞分泌的分子 调解这些影响仍然是一个悬而未决的问题。我最近发现了一本小说， 通过强力促血管生成分子的持续上调定义的反应性星形胶质细胞亚群 CCN家族成员1（CCN 1）。在我的建议中，我将利用两个独立但互补的目标来测试 假设Ccn 1+星形胶质细胞界定了一个进化的促血管生成组织生态位， SCI后通过直接控制内皮细胞表型（包括细胞增殖、成熟或 陷波信号。在目标1中，我将分析第一个纵向空间转录组学数据集， 在SCI的小鼠半切模型（mhSCI）中的组织区域，以A）询问 脊柱内组织小生境中含有Ccn 1+星形胶质细胞，和B）为SCI领域建立了强大的资源。从 这个目标，我将了解独特的分子特征Ccn 1+星形胶质细胞龛和计算推断， 相关生物过程、信号级联和转录调节因子的进化。在Aim 2中，我会 通过利用新产生的星形胶质细胞特异性CCN 1敲除来补充来自Aim 1的计算数据 小鼠用于A）运动恢复的行为测定和B）内皮细胞的组织学评估 mhSCI后的表型。从这个目的出发，我将探讨CCN 1对SCI的治疗潜力， 对内皮细胞特化的影响。总之，这项研究将揭示血管生成的潜力， 组织壁龛窝藏Ccn 1+星形胶质细胞，并开始提供一个潜在的作用机制一瞥。 这些发现可能对开发新的治疗方法具有重要意义， 为脊髓损伤后再生轴突发芽提供更宽松的环境。