Hematopoietic Stem and Progenitor Cells with Elevated Central Carbon Metabolism Drive the Aging Process in Human Bone Marrow

中心碳代谢升高的造血干细胞和祖细胞驱动人类骨髓的衰老过程

• 批准号: 461086654
• 负责人: Professor Dr. Anthony D. Ho
• 金额: --
• 依托单位: Klinik für Hämatologie, Onkologie und Rheumatologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/461086654?language=en
• 关键词: Hematopoietic; Stem; Progenitor; Cells; Elevated

Comprehensive proteomic studies have demonstrated a remarkable increase in abundance of proteins involved in central carbon metabolism of human hematopoietic stem and progenitor cells (HSPC) with age. Following this cue, we have shown that HSPCs from older subjects can be fractionated into three distinct subsets with high, intermediate, and low glucose uptake capacity (GU-high, GU-inter, GU-low). Single cell transcriptome (scRNA-seq) studies subsequently revealed that the GU-high subset is highly enriched for senescent cells in the HSPC compartment of older (>60 years) subjects but hardly detectable in young (<30 years) subjects. Pathway analyses of the scRNA-seq data showed a higher expression of genes involved in myeloid development, inflammation and stress response, DNA damage and repair, and activation of cell cycle checkpoint genes in the GU-high subset. Above all, the GU-high subset is equipped with activated anti-apoptotic, pro-survival mechanisms. The first goal of this project is to verify if anti-apoptosis is responsible for the survival advantage of senescent cells in the human HSPC compartment, and if elimination of this subset by inhibitors of anti-apoptotic factors may restore the functional integrity of aging human HSPCs. We have generated data showing that recurrent somatic mutations associated with clonal hematopoiesis of indeterminate potential (CHIP) are mainly present in GU-high subset. The second goal of this proposal is to simultaneously analyze (a) recurrent somatic mutations associated with CHIP, (b) transcriptome profile, and (c) central carbon metabolism in the same individual HSPCs to unambiguously link these processes. We will combine index-sort strategies to quantify glucose uptake with MutaSeq to interrogate transcriptome profile and somatic mutations in single cells. By determining the connections among these layers in the same cells we expect to gain relevant and mechanistic insight into the heterogeneity spectrum of senescent HSPCs with age and identify further novel targets for senolysis. It is highly likely that cellular senescence is a series of progressive and phenotypically diverse states subsequent to initial growth arrest. Whereas inhibition of pro-survival mechanisms using “senolytic” agents may represent one promising strategy, additional targets may be identified by our combined experimental design at a single cell level. Our proposal will therefore contribute to a better understanding of the heterogeneity of cellular senescent in the human HSPC compartment, and will serve as a guidance for a correspondingly targeted approach to the emerging field of “senotherapy”.

全面的蛋白质组学研究表明，随着年龄的增长，参与造血干细胞和祖细胞（HSPC）中心碳代谢的蛋白质丰度显著增加。根据这一线索，我们已经表明，来自老年受试者的HSPC可以分为三个不同的亚组，具有高、中和低葡萄糖摄取能力（高、中、低）。随后的单细胞转录组（scRNA-seq）研究显示，在老年（>60岁）受试者的HSPC区室中，高GU亚群高度富集衰老细胞，但在年轻（<30岁）受试者中几乎检测不到。scRNA-seq数据的通路分析显示，在GU-高亚群中，参与骨髓发育、炎症和应激反应、DNA损伤和修复以及细胞周期检查点基因激活的基因表达更高。最重要的是，高GU亚群具有激活的抗凋亡、促存活机制。本项目的第一个目标是验证抗凋亡是否是人HSPC隔室中衰老细胞存活优势的原因，以及通过抗凋亡因子抑制剂消除该亚群是否可以恢复衰老人HSPC的功能完整性。我们已经生成的数据显示，与不确定潜能的克隆性造血（CHIP）相关的复发性体细胞突变主要存在于高GU亚群中。该提议的第二个目标是同时分析同一个体HSPC中的（a）与CHIP相关的复发性体细胞突变，（B）转录组谱，和（c）中心碳代谢，以明确地将这些过程联系起来。我们将结合联合收割机索引排序策略，用MutaSeq定量葡萄糖摄取，以询问单细胞中的转录组谱和体细胞突变。通过确定相同细胞中这些层之间的连接，我们期望获得对衰老HSPC随年龄的异质性谱的相关和机制性洞察，并确定衰老的进一步新靶点。细胞衰老很可能是继初始生长停滞之后的一系列进行性和表型多样性状态。而使用“senolytic”剂抑制促存活机制可能代表一种有希望的策略，通过我们在单细胞水平的组合实验设计可以鉴定另外的靶点。因此，我们的建议将有助于更好地了解人类HSPC隔室中细胞衰老的异质性，并将作为指导，为新兴领域的“衰老疗法”提供相应的靶向方法。