Stem Cells And Neurogenesis

干细胞和神经发生

• 批准号: 8335818
• 负责人: Mark Mattson
• 金额: $ 3.93万
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8335818
• 关键词: Adult; Adverse effects; Affect; Alkaline Phosphatase; Alleles; Apical; Applied Research; Astrocytes; Axon; BHLH Protein; Basic Science; Binding; Blocking Antibodies; Botanicals; Brain; Brain Neoplasms; Brain-Derived Neurotrophic Factor; Bromodeoxyuridine; CXCR4 gene; Cell Fate Control; Cell Line; Cell Lineage; Cell Proliferation; Cells; Cerebral cortex; Coculture Techniques; Defect; Deoxyuridine; Development; Disease; Embryo; Embryonic Development; Enzymes; Epigenetic Process; Erinaceidae; Exhibits; Feedback; Flow Cytometry; Fluorescence-Activated Cell Sorting; Fostering; Gene Expression; Genetic; Genome; Germ; Glial Differentiation; Glial Fibrillary Acidic Protein; Glioblastoma; Glycolipids; Green Fluorescent Proteins; Growth; Histone H3; Human; Image; Injury; Integrin Binding; Integrins; Karyotype; Knowledge; Label; Laminin; Ligands; Mediating; Metabolic; Modeling; Molecular; Molecular Profiling; Molecular Weight; Morphology; Motor Neurons; Multiple Sclerosis; Mus; Myoblasts; Neocortex; Neonatal; Nervous system structure; Neuraxis; Neurologic; Neurons; Nitric Oxide; Octamer Transcription Factor-3; Oligodendroglia; Peptides; Pesticides; Phytochemical; Play; Population; Pregnancy; Production; Proliferating; Proliferating Cell Nuclear Antigen; Proteins; Radiation; Rattus; Recurrence; Regulation; Relative (related person); Reporting; Research; Resistance; Rodent; Role; Serotonin; Side; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Spinal Cord; Stat3 protein; Stem cells; System; TLR3 gene; Telencephalon; Time; Transcription Repressor/Corepressor; Transgenes; Transplantation; Traumatic Brain Injury; Tretinoin; Undifferentiated; Variant; Ventricular; Wild Type Mouse; Work; activating transcription factor; adhesion process; adult stem cell; base; brain cell; cancer stem cell; cell behavior; cytotoxicity; early embryonic stage; human embryonic stem cell; human embryonic stem cell line; immunocytochemistry; in utero; in vivo; inhibitor/antagonist; interdisciplinary approach; migration; monoamine; mortality; nerve stem cell; nervous system disorder; neurogenesis; neuroregulation; novel; novel strategies; plumbagin; pluripotency; postnatal; prevent; progenitor; protein expression; relating to nervous system; research study; response; self-renewal; stem; stem cell differentiation; stemness; telomere; therapeutic target; tool; tumor

We have made considerable progress towards understanding the cellular and molecular mechanisms that regulate the proliferation, differentiation and survival of neural progenitor cells in the developing and adult central nervous system. We found that nitric oxide and BDNF function in a positive feedback loop to promote neurogenesis. In other studies we found that SDFalpha, activates CXCR4 in glial progenitor cells resulting in increased migration and differentation of those cells. Our recent research has revealed a new molecular signaling system that regulates the fate of neural stem cells in the cerebral cortex. We used antibody-blocking and genetic experiments to reveal an requirement for laminin/integrin interactions in apical process adhesion and neural stem cell regulation. Transient abrogation of integrin binding and signalling using blocking antibodies to specifically target the ventricular region in utero results in abnormal cerebral cortex development. Using a multidisciplinary approach to analyse stem cell behaviour by expression of fluorescent transgenes and multiphoton time-lapse imaging revealed that the transient embryonic disruption of laminin/integrin signalling resulted in substantial layering defects in the postnatal neocortex. We have also investigated the roles of glial progenitor cells in the response of the nervous system to injury in models of traumatic brain injury and multiple sclerosis. This research is contributing to the development of novel approaches for treating neurological disorders based on treatments that stimulate stem cells to form new neurons that integrate into functional circuitry thereby reversing the damage caused by injury or disease. In other studies we found that mice lacking the monoamine metabolic enzymes MAO A and MAO B (MAO AB-deficient mice) exhibit diminished proliferation of neural stem cells (NSC) in the developing telencephalon beginning in late gestation embryonic day (E) 17.5, a deficit that persists in neonatal and adult mice. The results suggest that a MAO-dependent long-lasting alteration in the proliferation capacity of NSC occurs late in embryonic development and is mediated by serotonin. Glioblastoma brain tumors harbor a small population of cancer stem cells that are resistant to conventional chemotherapeutic and radiation treatments, and are believed responsible for tumor recurrence and mortality. The identification of the epigenetic molecular mechanisms that control self-renewal of glioblastoma stem cells will foster development of targeted therapeutic approaches. The transcriptional repressor REST, best known for its role in controlling cell fate decisions in neural progenitor cells, may also be crucial for cancer stem cell self-renewal. We discovered that reduced TRF2 binding to REST targets REST for proteasomal degradation and thereby inhibits cancer stem cell proliferation. Neurological side effects of treatments that target REST and TRF2 may be less severe than conventional brain tumor treatments because postmitotic neurons do not express REST and have relatively stable telomeres. Recently,we found that TLR3 protein is present in brain cells in early embryonic stages of development, and in cultured neural stem/progenitor cells (NPC). NPC from TLR3-deficient embryos formed greater numbers of neurospheres compared with neurospheres from wild-type embryos. Numbers of proliferating cells, as assessed by phospho histone H3 and proliferating cell nuclear antigen labeling, were also increased in the developing cortex of TLR3-deficient mice compared with wild-type mice in vivo. Treatment of cultured embryonic cortical neurospheres with a TLR3 ligand (polyIC) significantly reduced proliferating (BrdU-labeled) cells and neurosphere formation in wild type but not TLR3(-/-)-derived NPCs. Our findings reveal a novel role for TLR3 in the negative regulation of NPC proliferation in the developing brain. In a recent screen of a panel of botanical pesticides, we identified plumbagin as having neuroprotective activity. Recently, we determined if plumbagin could modify the developmental fate of rat E14.5 embryonic neural progenitor cells (NPC). Plumbagin exhibited no cytotoxicity when applied to cultured NPC at concentrations below 1 microM. At a concentration of 0.1 muM, plumbagin significantly enhanced the proliferation of NPC as indicated by a 17% increase in the percentage of cells incorporating bromo-deoxyuridine. Plumbagin at a concentration of 0.1 pM (microM), stimulated the production of astrocytes as indicated by increased GFAP expression. Plumbagin selectively induced the proliferation and differentiation of glial progenitor cells without affecting the proliferation or differentiation of neuron-restricted progenitors. Plumbagin (0.1 pM) rapidly activated the transcription factor signal transducer and activator of transcription 3 (Stat3) in NPC, and a Stat3 inhibitor peptide prevented both plumbagin-induced astrocyte formation and proliferation. These findings demonstrate the ability of a low molecular weight naturally occurring phytochemical to control the fate of glial progenitor cells by a mechanism involving the Stat3 signaling pathway.

我们在理解调节增殖的细胞和分子机制方面取得了相当大的进展， 发育中和成人中枢神经系统中神经祖细胞的分化和存活。 我们发现硝酸 氧化物和 BDNF 在正反馈回路中发挥作用，促进神经发生。 在其他研究中，我们发现 SDFalpha 激活 神经胶质祖细胞中的 CXCR4 导致这些细胞的迁移和分化增加。 我们最近的研究表明 一种新的分子信号系统，调节大脑皮层神经干细胞的命运。 我们使用抗体阻断和 遗传实验揭示顶突粘附和神经干细胞中层粘连蛋白/整合素相互作用的要求 规定。使用阻断抗体特异性靶向心室，瞬时消除整合素结合和信号传导 子宫内区域会导致大脑皮层发育异常。 使用多学科方法分析干细胞行为 通过荧光转基因的表达和多光子延时成像揭示了短暂的胚胎破坏 层粘连蛋白/整合素信号传导导致出生后新皮质的严重分层缺陷。 我们还研究了神经胶质祖细胞在创伤模型中神经系统损伤反应中的作用 脑损伤和多发性硬化症。 这项研究有助于开发治疗神经系统疾病的新方法 基于刺激干细胞形成新神经元的治疗的疾病，这些新神经元整合到功能电路中，从而逆转 受伤或疾病造成的损害。 在其他研究中，我们发现缺乏单胺代谢酶 MAO A 和 MAO B（MAO AB 缺陷小鼠）的小鼠表现出减弱的 发育中的端脑中神经干细胞 (NSC) 的增殖从妊娠晚期胚胎日 (E) 17.5 开始，缺陷 这种现象在新生小鼠和成年小鼠中持续存在。结果表明，MAO 依赖性增殖能力的长期改变 NSC 发生在胚胎发育后期，由血清素介导。 胶质母细胞瘤脑肿瘤含有一小群癌症干细胞，这些细胞对传统化疗和药物具有抵抗力 放射治疗被认为是导致肿瘤复发和死亡的原因。表观遗传分子的鉴定 控制胶质母细胞瘤干细胞自我更新的机制将促进靶向治疗方法的发展。这 转录抑制因子 REST 以其在神经祖细胞中控制细胞命运决定的作用而闻名，也可能是 对于癌症干细胞的自我更新至关重要。 我们发现减少 TRF2 与 REST 的结合目标 REST 进行蛋白酶体降解 从而抑制癌症干细胞增殖。针对 REST 和 TRF2 的治疗的神经系统副作用可能较少 比传统脑肿瘤治疗更严重，因为有丝分裂后神经元不表达 REST 并且具有相对稳定的端粒。 最近，我们发现TLR3蛋白存在于发育早期胚胎阶段的脑细胞和培养的神经细胞中。 干/祖细胞（NPC）。与来自 TLR3 缺陷胚胎的 NPC 相比，来自 TLR3 缺陷胚胎的 NPC 形成了更多数量的神经球。 野生型胚胎。通过磷酸组蛋白 H3 和增殖细胞核抗原标记评估增殖细胞的数量， 与体内野生型小鼠相比，TLR3 缺陷小鼠的皮质发育中的 TLR3 水平也有所增加。培养的治疗 具有 TLR3 配体 (polyIC) 的胚胎皮质神经球显着减少增殖（BrdU 标记）细胞和神经球 在野生型中形成，但在 TLR3(-/-) 衍生的 NPC 中不形成。我们的研究结果揭示了 TLR3 在 NPC 负调控中的新作用 发育中的大脑增殖。 在最近对一组植物农药的筛选中，我们发现白花丹素具有神经保护活性。 最近，我们 确定白花丹素是否可以改变大鼠 E14.5 胚胎神经祖细胞 (NPC) 的发育命运。白花丹展出 当浓度低于 1 µM 应用于培养的 NPC 时，没有细胞毒性。在浓度为 0.1 μM 时，白花丹素显着 增强了 NPC 的增殖，表现为掺入溴脱氧尿苷的细胞百分比增加了 17%。白花丹 浓度为 0.1 pM (microM) 时，刺激星形胶质细胞的产生，如 GFAP 表达增加所示。白花丹 选择性诱导神经胶质祖细胞的增殖和分化，而不影响其增殖或分化 神经元限制性祖细胞的分化。白花丹素 (0.1 pM) 快速激活转录因子信号转导器并 NPC 中转录激活剂 3 (Stat3) 和 Stat3 抑制肽可阻止白花丹素诱导的星形胶质细胞形成和 增殖。这些发现证明了低分子量天然植物化学物质控制命运的能力 通过涉及 Stat3 信号通路的机制来形成神经胶质祖细胞。