Senescent Vascular Cells as Mediators of Cognitive Decline

项目总结 这项建议的目标是(1)获得必要的实验技能和职业培训，以发展 独立研究计划调查年龄依赖性认知衰退和阿尔茨海默氏症的机制 疾病发病机制和(2)确定细胞衰老是否对脑血管和 认知功能障碍。与年龄相关的脑血管恶化是导致脑血管疾病的重要因素 认知功能减退和阿尔茨海默病，但有针对性的潜在机制尚未发现。 细胞衰老已经成为衰老和许多与年龄相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和 功能。尽管众所周知，与年龄相关的血管衰退和认知之间的关系，是否 衰老细胞和SASP是如何导致脑血管和认知功能障碍的 探索过了。拟议的项目将使用年轻的(6个月)和老龄的(26个月)p16-Ink-Attac小鼠，其中 衰老的细胞可以被GFP监测或删除。我们还将测试敏感药物的效果，这些药物会杀死 衰老的细胞。并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。目标1将确定大脑中衰老的细胞类型 并将比较体内细胞群体中转基因细胞和裂解细胞的清除效率。目标2 将利用体内和体外实验来检验衰老的脑血管细胞 分泌一种前重塑和促炎SASP，促进血脑屏障通透性和炎症，并 可能被衰老的细胞清除所缓解。目标3将检验这样一种假设，即去除衰老细胞 改善老年小鼠的血管运动和认知功能。K99阶段将在梅奥诊所和 将专注于以完成拟议目标所需的方法获得指导培训，在 体外和体内实验，并发布细胞类型分析和体外结果。R00阶段将是 在我的独立实验室进行，将专注于分析小鼠组织和数据，发布所有活体内的 并基于这些结果开发一个R01应用程序。拟议的计划使新技能更具协同性 在高级成像、血管生理学和认知测试方面，具有脑老化和细胞方面的专业知识 我的研究方向不同于我导师的关注点。这项工作将产生一个 为阐明细胞衰老机制和翻译的独立研究事业奠定了坚实的基础 认知功能减退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.