Basic Aspects of Hematopoietic Stem Cells and Aging

造血干细胞和衰老的基本方面

• 批准号: 9433046
• 负责人: PETER J. QUESENBERRY
• 金额: $ 28.98万
• 依托单位: RHODE ISLAND HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-15 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9433046
• 关键词: Age; Aging; Alpha Cell; Attention; Biological Assay; Bone Marrow; Bone Marrow Transplantation; Bromodeoxyuridine; Cell Aging; Cell Cycle; Cell physiology; Cells; Characteristics; Data; Development; Engraftment; Epitopes; FRAP1 gene; Family; Female; Functional disorder; Hematological Disease; Hematopoiesis; Hematopoietic; Hematopoietic stem cells; Immune system; Incidence; Individual; Investigation; Knowledge; Label; Lead; Marrow; Mus; Myelogenous; Phenotype; Population; Proliferating; Proto-Oncogene Protein c-kit; Reactive Oxygen Species; Regulation; Role; SLAM protein; Staining method; Stains; Stem cells; Suicide; Surface; System; Thymidine; Transplantation; Work; age effect; age related; aged; base; functional status; in vivo; male; mitochondrial metabolism; senescence; stem cell population; telomere

Project Summary: Changes in hematopoiesis and hematopoietic stem cells are an important component of aging. Many critical studies on the roles in hematopoietic aging of telomere dysfunction, cellular senescence and induction of the senescence-associated secretory phenotype, sitruin family effects, mitochondrial metabolism, the mechanistic target of rapamycin (mTOR), decline in the immune system and changes induced by a variety of toxic entities many of which involve Reactive Oxygen Species (ROS) were carried out employing highly purified hematopoietic stem cells. Studies on purified murine hematopoietic stem cells as exemplified by lineage negative c- kit+Sca-1+ (LSK) cells with or without CD150 marking, have indicated that with aging the number of phenotypically defined stem cells increases while the function of these cells decreases and myeloid skewing occurs. Much of the work on hematopoiesis in the aged has relied on studies of purified stem cells and is based on the assumption that these cells are non cycling or dormant. However, our work has shown that the long-term multi-lineage repopulating cell in lethally irradiated hosts is actively cycling and always changing. The key to these findings was the study of whole un-separated marrow stem cells with long-term multi-lineage engraftment as the assay. We feel that most studies to date on hematopoietic stem cells in aging have used purified stem cells, which are not representative of the true marrow stem cell populations. We propose here to study the content, cell cycle status and differentiation characteristics of un-separated marrow stem cells in young and aged mice and in male and female mice. We will separate cells into G0, G1 and S/G2/M fractions and evaluate engraftment. We will also utilize tritiated thymidine suicide to assess cycle status of stem cells in un- separated marrow and in vivo bromodeoxyuridine (BrdU) labeling to assess the flux of stem cells through cell cycle. These studies should give an important new base for further studies on the effects of aging on hematopoietic stem cells.

项目概要： 造血和造血干细胞的变化是衰老的重要组成部分。 许多关于端粒功能障碍、细胞衰老在造血衰老中的作用的批判性研究 衰老和衰老相关分泌表型、sitruin 家族的诱导 影响、线粒体代谢、雷帕霉素 (mTOR) 的机制靶点、 免疫系统和由多种有毒物质引起的变化，其中许多涉及 采用高度纯化的造血干细胞进行活性氧 (ROS) 检测 细胞。以谱系阴性 c- 为例的纯化小鼠造血干细胞的研究 kit+Sca-1+ (LSK) 细胞有或没有 CD150 标记，表明随着年龄的增长 表型定义的干细胞数量增加，而这些细胞的功能 减少并发生骨髓偏斜。许多关于老年人造血的工作已经 依赖于对纯化干细胞的研究，并基于这些细胞非 骑自行车或休眠。然而，我们的工作表明，长期的多谱系重新繁殖 受到致命辐射的宿主体内的细胞正在活跃地循环并且总是在变化。这些发现的关键 是对具有长期多谱系的完整未分离骨髓干细胞的研究 植入作为测定。我们认为迄今为止大多数关于造血干细胞的研究 老化使用的是纯化的干细胞，并不代表真正的骨髓干细胞 人口。我们在这里建议研究内容、细胞周期状态和分化 年轻和老年小鼠以及雄性和雄性小鼠中未分离的骨髓干细胞的特征 雌性小鼠。我们将细胞分为 G0、G1 和 S/G2/M 部分并评估植入。 我们还将利用氚化胸苷自杀来评估非干细胞的周期状态。 分离骨髓和体内溴脱氧尿苷 (BrdU) 标记以评估干通量 细胞经历细胞周期。这些研究将为进一步研究提供重要的新基础 衰老对造血干细胞的影响。