The roles of lipid metabolism in the maintenance of hematopoietic stem cells

脂质代谢在造血干细胞维持中的作用

• 批准号: 9135829
• 负责人: Keisuke Ito
• 金额: $ 10.32万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE, INC
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9135829
• 关键词: Ablation; Acetylation; Activities of Daily Living; Acute Promyelocytic Leukemia; Agonist; Arsenic Trioxide; Biological Assay; Bone Marrow Cells; Cancer Center; Carnitine; Cell Cycle; Cell Maintenance; Cell physiology; Cells; Clinic; Clinical Trials; Cues; Data; Defect; Development; Dose; Drug Targeting; Effectiveness; Embryo; Energy Metabolism; Engraftment; Equilibrium; Exhibits; Fibroblasts; Gene Expression Profile; Gene Targeting; Genetic; Genetically Engineered Mouse; Goals; Health; Hematology; Hematopoietic; Hematopoietic stem cells; Homeostasis; Human; Image; In Vitro; Institutional Review Boards; Invertebrates; Knock-in Mouse; Knock-out; Knockout Mice; Lead; Link; Longevity; Maintenance; Measures; Medicine; Metabolic; Metabolic Diseases; Metabolic Pathway; Metabolism; Modeling; Molecular; Mus; Nature; Normal Cell; Oncology; Organism; PPAR delta; PPAR gamma; Pathology; Pathway interactions; Patients; Pattern; Peroxisome Proliferator-Activated Receptors; Personal Satisfaction; Play; Prevention; Regulation; Regulatory Element; Research; Research Design; Role; Signal Transduction; Source; System; Technology; Testing; Time; Tissues; Transferase; Transplantation; Vertebrates; Work; Xenograft procedure; clinical application; daughter cell; exhaustion; fatty acid metabolism; fatty acid oxidation; human stem cells; in vivo; inhibitor/antagonist; leukemia; leukemic stem cell; lipid metabolism; malignant breast neoplasm; mouse model; novel; novel therapeutic intervention; novel therapeutics; obesity treatment; pre-clinical; progenitor; programs; promoter; reconstitution; response; self-renewal; stem; stem cell division; stem cell fate; stem cell niche; stem cells; transcriptome sequencing

DESCRIPTION (provided by applicant): Hematopoietic stem cells are the source of all hematopoietic cells, and replenish the hematopoietic compartment as required throughout organism lifespan. Since alterations in the equilibrium of this compartment greatly impact stem cell maintenance, the molecular mechanisms regulating the cell fate decisions of stem cells hold great promise for clinical applications. Studies of genetically-engineered mouse models suggest that metabolic cues contribute to the governance of these cells' self-renewal capacity. To date, however, little is known regarding the role of lipid metabolism in stem cell homeostasis. To better understand the key metabolic pathways involved in stem cell fate and maintenance, we propose the following Specific Aims: 1. To investigate the effects of inactivation of PPAR-fatty acid oxidation in stem cells; We have previously shown that stem cells exhibit higher Ppard expression and fatty acid oxidation than committed progenitor cells, and have hypothesized that lipid metabolism plays a role in their repopulation capacity. In accordance with this premise, we have also found that inhibition of fatty acid oxidation in vitro leads to a reduction of long-term culture-initiating cell capacity. Furthermore, Ppard-ablation leads to reduction of fatty acid oxidation in the hematopoietic stem cell compartment. The current proposal aims to elucidate the effect of genetic loss of Ppard in vivo on the reconstitution ability of stem cells in a transplantation setting. Stem cell division assays with Ppard knockout models will allow us to test whether Ppard-ablation leads to increased commitment of stem cells during their division. 2. To enable long-term engraftment with minimal donor cells by the activation of PPAR signaling; we will employ different activators of PPAR¿ at low doses in vivo to observe their effects on the long-term maintenance of murine stem cells from Ppard wild-type and knockout mice. This will provide a definitive proof, in a PPAR¿-dependent manner, of the potential benefit of PPAR¿ activators in the stem cell compartment. We will then determine, through the use of xenograft mouse models transplanted with human bone marrow cells, whether pharmacological activation of PPAR signaling induces a transplanted minimum number of human hematopoietic stem cells to maximize their long-term repopulation capacity in vivo. 3. To identify cell fate determinants that maintain stem cell-ness through division balance control; in stark contrast to what is known about symmetric and asymmetric division of normal cells in invertebrates, it has been extremely difficult to image the division pattern of most purified stem cell compartments in vertebrates. We therefore propose to generate knock-in mouse lines for real-time imaging of stem cell divisions and to study the intrinsic and extrinsic signals regulating stem cell decision. Combined with the data from our whole transcriptome analysis by RNA-seq in the purified stem cell compartment, the results from these mouse models will lead to a deeper understanding of the cell fate determinants of stem cells. These proposed studies will identify a novel metabolic switch for the cell fate decisions of stem cells, and in turn open new therapeutic avenues for the manipulation of hematopoietic stem cell function, and possibly the function of leukemia stem cells. This work will be conducted with the support of the following experts; Drs. Michael A. Brownlee (Metabolism), Chih-Hao Lee (Metabolism), David E. Avigan (Hematology/Oncology), Julie Teruya-Feldstein (Hemato- pathology), Toshio Suda (Stem Cells), Jan Vijg (Genetics), and Winfried Edelman (Gene Targeting). Importantly, Dr. Paul S. Frenette (Stem Cell niche) is closely supporting our research program along with Dr. Arthur Skoultchi (Hematology).

描述（由应用提供）：造血干细胞是所有造血细胞的来源，并根据整个生物体寿命所需的需要复制造血室。由于该隔室等效的变化极大地影响了干细胞的维持，因此确定干细胞细胞脂肪决策的分子机制对于临床应用有很大的希望。对遗传学工程小鼠模型的研究表明，代谢线索有助于这些细胞的自我更新能力的治理。然而，迄今为止，关于脂质代谢在干细胞稳态中的作用知之甚少。为了更好地了解干细胞命运和维持中涉及的主要代谢途径，我们提出了以下特定目的：1。研究干细胞中PPAR-fatty酸氧化的灭活影响；我们先前已经表明，与承诺的祖细胞相比，干细胞表现出更高的PPARD表达和脂肪酸氧化，并且假设脂质代谢在其重生能力中起作用。根据这一前提，我们还发现，体外抑制脂肪酸氧化会导致长期培养的培养细胞容量的降低。此外，PPARD燃烧会导致造血干细胞室中脂肪酸氧化的减少。当前的提案旨在阐明体内PPARD遗传丧失对在移植设置中干细胞重构能力的影响。使用PPARD敲除模型的干细胞分裂测定将使我们能够测试PPARD启动是否会导致干细胞在分裂过程中的承诺增加。 2。通过激活PPAR信号传导，可以长期植入最小的供体细胞；我们将在低剂量的体内使用不同的PPAR的活化剂，以观察它们对PPARD野生型和敲除小鼠对鼠干细胞的长期维持的影响。这将以依赖性的方式提供一个确定的证据，以证明PPAR活动在干细胞室中的潜在益处。然后，我们将通过使用用人骨髓细胞移植的异种移植小鼠模型来确定PPAR信号传导的药物激活是否会诱导移植的最少人数人造血干细胞，以最大程度地促进其长期重生能力。 3。确定通过分裂平衡控制维持干细胞的细胞命运决定者；与无脊椎动物中正常细胞的对称和不对称分裂所知的形成鲜明对比的是，很难对脊椎动物中大多数纯化的干细胞隔室的分裂模式进行成像。因此，我们建议生成敲入小鼠系，以实时对干细胞分裂的实时成像，并研究确定干细胞决策的内在和外在信号。结合RNA-seq在纯化的干细胞室中我们整个转录组分析的数据结合在一起，这些小鼠模型的结果将导致对干细胞的细胞脂肪决定剂的更深入了解。这些提出的研究将确定用于干细胞细胞脂肪决策的新型代谢开关，进而开放新的治疗途径，以操纵造血干细胞功能，以及白血病干细胞的功能。这项工作将在以下专家的支持下进行；博士。 Michael A. Brownlee（代谢），Chih-Hao Lee（代谢），David E. Avigan（血液学/肿瘤学），Julie Teruya-Feldstein（Hemato-Pathology）（Hemato-Pathology），Toshio Suda（干细胞）（干细胞），Jan Vijg（遗传学）和Winfried Edelman（Gene Edelman（Gene Targeting）。重要的是，Paul S. Frenette博士（干细胞生态位）与Arthur Skoultchi博士（血液学）密切支持我们的研究计划。