Senescent Vascular Cells as Mediators of Cognitive Decline

项目摘要 本建议的目标是（1）获得必要的实验技能和职业培训，以发展一个 一个独立的研究项目，调查年龄依赖性认知衰退和阿尔茨海默氏症的机制 疾病的发病机制和（2）确定细胞衰老是否有助于脑血管和 认知功能障碍血管相关的血管恶化是一个重要因素， 认知能力下降和阿尔茨海默氏病，但尚未发现有针对性的潜在机制。 细胞衰老已经成为衰老和许多与年龄有关的疾病的统一特征。 通过衰老相关分泌表型（SASP），衰老细胞损害组织结构， 功能尽管年龄相关的血管功能下降和认知之间的关系众所周知， 以及衰老细胞和SASP如何导致脑血管和认知功能障碍， 探讨了拟议的项目将使用年轻（6个月）和老年（26个月）p16-Ink-Attac小鼠，其中 衰老细胞可以被GFP监测或删除。我们还将测试抗衰老药物的效果， 衰老细胞平行的转基因和药物消除策略将使我们能够机械地- 探索衰老细胞的特性和作用。目的1将确定脑中衰老的细胞类型 老化，并将在体内跨细胞群比较转基因和衰老清除细胞的清除效率。目的2 将利用体内和体外实验来验证衰老的脑血管细胞 分泌促重塑和促炎SASP，其促进BBB渗透性和炎症， 可以通过衰老细胞清除来缓解。目的3将检验衰老细胞去除 改善老年小鼠的血管扩张和认知功能。K99阶段将在马约诊所进行， 将侧重于获得完成拟议目标所需方法的指导培训， 体外和体内实验，并发表细胞类型分析和体外结果。R 00阶段将是 在我的独立实验室进行，并将专注于分析小鼠组织和数据， 研究结果，并根据这些结果开发R 01应用程序。拟议的计划使新技能协同增效 在先进的成像，血管生理学和认知测试与先前的专业知识，在脑老化和细胞 衰老创造一个研究轨迹，是从我的导师的焦点不同。这项工作将产生 一个独立的研究生涯的坚实基础，阐明细胞衰老机制和翻译 认知能力下降和阿尔茨海默病的潜在解决方案。

PROJECT SUMMARY The goals of this proposal are to (1) obtain experimental skills and career training necessary to develop an independent research program investigating mechanisms of age-dependent cognitive decline and Alzheimer’s disease pathogenesis and (2) determine whether cellular senescence contributes to cerebrovascular and cognitive dysfunction. Age-related deterioration of the cerebrovasculature is an important contributor to cognitive decline and Alzheimer’s disease, but targetable underlying mechanisms have yet to be discovered. Cellular senescence has emerged as a unifying feature of aging and numerous age-related conditions. Through the senescence-associated secretory phenotype (SASP), senescent cells impair tissue structure and function. Despite the well-known relationships between age-related vascular decline and cognition, whether and how senescent cells and the SASP contribute to cerebrovascular and cognitive dysfunction has not been explored. The proposed project will use young (6 months) and aged (26 months) p16-Ink-Attac mice, in which senescent cells can be GFP-monitored or deleted. We will also test the effects of senolytic drugs, which kill senescent cells. Parallel transgenic and pharmacological elimination strategies will enable us to mechanistical- ly explore the identity and effects of senescent cells. Aim 1 will identify the cell types that senesce in brain aging and will compare transgenic and senolytic cell clearance efficiency across cell populations in vivo. Aim 2 will leverage in vivo and in vitro experiments to test the hypothesis that senescent cerebrovascular cells secrete a proremodeling and proinflammatory SASP, which promotes BBB permeability and inflammation and may be alleviated by senescent cell clearance. Aim 3 will test the hypothesis that senescent cell removal improves vasomotor and cognitive function in aged mice. The K99 phase will be conducted at Mayo Clinic and will focus on obtaining mentored training in methods required to complete the proposed aims, conducting in vitro and in vivo experiments, and publishing cell-type profiling and in vitro results. The R00 phase will be conducted in my independent lab and will focus on analyzing mouse tissues and data, publishing all in vivo findings, and developing an R01 application based on these results. The proposed plan synergizes new skills in advanced imaging, vascular physiology, and cognitive testing with prior expertise in brain aging and cellular senescence to create a research trajectory that is distinct from my mentors’ foci. This work will produce a robust foundation for an independent research career elucidating cellular aging mechanisms and translatable solutions underlying cognitive decline and Alzheimer’s disease.