Elucidating microvascular contributions to cognitive impairment at single-cell resolution

项目总结/摘要 痴呆症困扰着全世界超过5500万人。随着人口老龄化和没有有效的治疗方法 根据现有资料，预计到2050年，这一数字将增加近两倍。脑小血管病（CSVD）可导致 占所有痴呆症的45%，占中风的约20%，并出现在大多数阿尔茨海默病患者中。CSVD 是由大脑400英里长的输送氧气和营养的小动脉，小动脉， 小静脉和毛细血管;被认为是认知障碍的最重要的血管贡献者 痴呆症（VCID）CSVD病理学，如小动脉硬化和微梗死，在不知不觉中发展， 抑制脑血流，损害血脑屏障，并引发神经炎症。最近 单核测序技术的发展已经开始阐明基本的分子和 是人类神经疾病的基础他们揭示了选择性脆弱的细胞 人群，疾病阶段的转录功能障碍，以及遗传风险变异的机制， 为新的研究领域和治疗目标提供信息。然而，单细胞核研究大多失去了人类大脑 血管细胞原因不明，使我们对CSVD的认识滞后。为了应对这一挑战，我们 发明了用于测序的血管分离和细胞核提取（VINE-seq），以有效地捕获人脑 从冷冻的死后大脑中提取血管细胞类型用于单核分析。在这里，我们将联合收割机VINE-seq 多模式单核RNA和ATAC测序，以生成第一个约190万个血管图谱， 早期、中期和晚期CSVD以及年龄匹配的认知正常对照。样品来自 专门组织的191个死后额中回分水岭组织的CSVD集，通过MRI进行优先排序， 神经纤维束描记术，来自宗教秩序研究和记忆与衰老项目（ROSMAP）。样品 没有表现出混杂的非血管神经退行性病变， 基因组、病理和纵向认知数据，以将分子读数与表型联系起来。因此，我们将 将联合收割机VINE-seq与多模式单核RNA和ATAC测序（snRNA/ATAC-seq）结合， 显示CSVD进展的分子特征（A2）;以及 确定CSVD遗传风险的因果机制（A3）。由于血管风险因素是可以改变的， 这一发现对于理解和最终治疗VCID和混合病理性痴呆可能至关重要。

Project Summary/Abstract Dementia afflicts over 55 million people worldwide. With an aging population and no effective treatments available, this number is projected to nearly triple by 2050. Cerebral small vessel disease (CSVD) causes up to 45% of all dementia, accounts for ~20% of strokes, and appears in most Alzheimer’s disease patients. CSVD arises from pathologies of the brain’s ~400 miles of oxygen and nutrient-delivering small arteries, arterioles, venules, and capillaries; and is recognized as the most important vascular contributor to cognitive impairment and dementia (VCID). CSVD pathologies, such as arteriolosclerosis and microinfarcts, develop insidiously to strangulate cerebral blood flow, compromise the blood-brain barrier, and trigger neuroinflammation. Recent developments in single-nucleus sequencing technologies have begun elucidating fundamental molecular and cellular processes underlying human neurological disease. They have revealed selectively vulnerable cell populations, transcriptional dysfunction across disease stages, and the mechanisms of genetic risk variants to inform new research areas and therapeutic targets. Yet, single-nucleus studies have mostly lost human brain vascular cells unknown reasons, leaving our understanding of CSVD lagging. To address this challenge, we invented Vessel Isolation and Nuclei Extraction for Sequencing (VINE-seq) to efficiently capture human brain vascular cell types from frozen postmortem brains for single-nucleus profiling. Here, we will combine VINE-seq with multimodal single-nucleus RNA and ATAC sequencing to generate a first ~1.9 million vascular atlas of early, mid-, and late-stage CSVD alongside age-matched cognitively normal controls. Samples come from a specially organized CSVD set of 191 postmortem midfrontal gyrus watershed tissue, prioritized via MRI and nerve tractography, from the Religious Order Study and Memory and Aging Project (ROSMAP). Samples exhibit no confounding non-vascular neurodegenerative pathology and are richly annotated with demographic, genomic, pathologic, and longitudinal cognitive data to link molecular readouts to phenotypes. Thus, we will combine VINE-seq with multimodal single-nucleus RNA- and ATAC- sequencing (snRNA/ATAC-seq) to generate a first vascular atlas of CSVD (A1); reveal the molecular signatures of CSVD progression (A2); and determine the causal mechanisms of CSVD genetic risk (A3). As vascular risk factors are modifiable, insights revealed here may be critical to understanding and ultimately treating VCID and mixed pathology dementias.