Effect of Ethanol on Cell Proliferation

乙醇对细胞增殖的影响

• 批准号: 8066451
• 负责人: Frank A. Middleton
• 金额: $ 37.35万
• 依托单位: UPSTATE MEDICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8066451
• 关键词: Activity Cycles; Adult; Affect; Affinity; Alcohols; Attention deficit hyperactivity disorder; Autistic Disorder; Behavior; Brain; Cell Count; Cell Culture Techniques; Cell Cycle; Cell Cycle Kinetics; Cell Proliferation; Cell Proliferation Regulation; Cell Transplants; Cells; Cerebral cortex; Characteristics; Complement; Corpus Callosum; Defect; Development; Dorsal; Environmental Impact; Environmental Risk Factor; Equilibrium; Ethanol; Ethanol toxicity; Etiology; Event; Exposure to; Fetal Alcohol Exposure; Fetal Alcohol Spectrum Disorder; Functional disorder; Gene Silencing; Genes; Genetic; Genomics; Growth; Harvest; Health; Heterotopic Transplantation; Homeobox Genes; In Vitro; Indium; Kinetics; Ligands; Live Birth; Medial; Mental Retardation; Mental disorders; Methyl Green; Modeling; Mus; Neuraxis; Neurons; Neuropeptides; Pattern; Phase; Phenotype; Population; Process; Production; Proliferating; Proteins; Psyche structure; Regulation; Shapes; Site; Slice; Staging; Stem cells; Structure; System; Telencephalon; Testing; Transforming Growth Factors; Transplantation; United States; Variant; Ventricular; alcohol effect; brain size; defined contribution; excitatory neuron; in vivo; in vivo Model; inhibitory neuron; insight; migration; nerve stem cell; novel; prenatal exposure; progenitor; receptor; response; stem cell fate; subventricular zone

DESCRIPTION (provided by applicant): Understanding the effects of ethanol on neural stem cells is critical to unraveling the etiological knots of deficits associated with fetal alcohol spectrum disorder (FASD). FASD is a compelling problem because it is a major cause of developmental mental dysfunction affecting ~2% of all live births (indeed, it is the chief cause of mental retardation in the USA), and it provides insights into the etiology of other (often co-morbid) mental health disorders (e.g., attention deficit hyperactivity disorder and autism). The composition and size of the brain are established by the proliferation of neural stem cells and by the numbers and lineage of the derivatives. Improper numbers or balance of neuronal subpopulations can underlie mental dysfunction. Thus, we will test the hypothesis that ethanol affects the cycling behavior and fates of cells generated in the developing central nervous system. Cerebral cortex is composed of two types of neurons: excitatory projection neurons (PNs) and inhibitory local circuit neurons (LCNs). These derive prenatally from two distinct proliferative regions. PNs come from the dorsal telencephalon which comprises two zones: the ventricular zone (VZ) and its derivative, the subventricular zone (SZ). Most cortical LCNs are generated in the ventral telencephalon, in the medial ganglionic eminence (MGE). The fates of VZ/SZ and MGE cells are defined in a two-step process. (1) It is decided whether the cells remain in the cycling population and (2) the phenotype (e.g., the type of neuron) is defined. During the previous period of support, we showed that transforming growth factor (TGF) 21 is a key regulator of neural stem cell proliferation. The present project will explore the effects of ethanol on dynamics of cell proliferation and on the definition of cell fate. Specific Aims 1 and 2 will use an in vivo model to determine the effects of ethanol on the cycling activity (cell cycle kinetics and exit) and on the expression/activation of TGF2 receptors by neural stem cells in the cortical proliferative zones. During their development, neural stem cells express a homeobox gene product(s), Pax6 and/or Tbr2. These proteins define the transition from (Pax6+) stem cells in the VZ to an (Tbr2+) intermediate progenitor cell stage. This transition is critical for the development of superficial cortex (e.g., the origin of callosal projections) which is a target of prenatal exposure to ethanol. Specific Aim 3 will use two types of cultures (organotypic slices that retain in vivo-like organization and lines of neural stem cells harvested from the VZ/SZ or MGE) to explore the effects of ethanol on TGF21-regulated cell proliferation and fate decisions. In addition, we will identify genes that are up- and down-regulated and silenced (methylated) by ethanol and/or TGF21. In Specific Aim 4, neural stem cells will be transplanted (homotopically or heterotopically) to determine the effects of ethanol and/or TGF21 on genetic and environmental contributions to determining cycling behavior and to defining cell fate. In concert, the novel Aims will use three complementary models to gain critical insight into mechanisms defining cell proliferation and fate and the effects of ethanol on these critical factors. PUBLIC HEALTH RELEVANCE: Fetal alcohol spectrum disorder affects an estimated 2% of all live births in the United States. One common target of alcohol toxicity is proliferating cells, particularly neural stem cells that give rise to the brain. The present study will explore a mechanism by which alcohol-induced defects result - from changes (a) in the fates of proliferating neural stem cells and (b) in their response to a key regulator of that proliferation, transforming growth factor.

描述（由申请人提供）：了解乙醇对神经干细胞的影响对于解开与胎儿酒精谱系障碍（FASD）相关的缺陷的病因学结至关重要。 FASD 是一个引人注目的问题，因为它是影响约 2% 活产婴儿的发育性精神功能障碍的主要原因（事实上，它是美国精神发育迟滞的主要原因），并且它提供了对其他（通常是共病的）精神健康障碍（例如，注意力缺陷多动障碍和自闭症）病因学的见解。大脑的组成和大小是由神经干细胞的增殖及其衍生物的数量和谱系决定的。神经元亚群的数量或平衡不当可能是精神功能障碍的基础。因此，我们将检验乙醇影响发育中的中枢神经系统中产生的细胞的循环行为和命运的假设。大脑皮层由两种类型的神经元组成：兴奋性投射神经元（PN）和抑制性局部回路神经元（LCN）。这些在出生前源自两个不同的增殖区域。 PN 来自背端端脑，它包括两个区域：心室区 (VZ) 及其衍生物，心室下区 (SZ)。大多数皮质 LCN 是在内侧神经节隆起 (MGE) 的腹侧端脑中生成的。 VZ/SZ 和 MGE 细胞的命运通过两步过程确定。 (1) 决定细胞是否保留在循环群体中，以及 (2) 定义表型（例如神经元的类型）。在之前的支持期间，我们证明转化生长因子（TGF）21是神经干细胞增殖的关键调节因子。本项目将探讨乙醇对细胞增殖动力学和细胞命运定义的影响。具体目标 1 和 2 将使用体内模型来确定乙醇对循环活动（细胞周期动力学和退出）以及皮质增殖区神经干细胞 TGF2 受体表达/激活的影响。在发育过程中，神经干细胞表达同源盒基因产物 Pax6 和/或 Tbr2。这些蛋白质定义了从 VZ 中的 (Pax6+) 干细胞到 (Tbr2+) 中间祖细胞阶段的转变。这种转变对于浅层皮质（例如胼胝体投射的起源）的发育至关重要，浅层皮质是产前接触乙醇的目标。具体目标 3 将使用两种类型的培养物（保留体内样组织的器官切片和从 VZ/SZ 或 MGE 收获的神经干细胞系）来探索乙醇对 TGF21 调节的细胞增殖和命运决定的影响。此外，我们将鉴定被乙醇和/或 TGF21 上调、下调和沉默（甲基化）的基因。在具体目标 4 中，神经干细胞将被移植（同位或异位）以确定乙醇和/或 TGF21 对遗传和环境贡献的影响，从而确定循环行为和定义细胞命运。总之，新的目标将使用三个互补模型来深入了解定义细胞增殖和命运的机制以及乙醇对这些关键因素的影响。公共卫生相关性：在美国，估计有 2% 的活产婴儿受到胎儿酒精谱系障碍的影响。酒精毒性的一个常见目标是增殖细胞，特别是产生大脑的神经干细胞。本研究将探索酒精引起的缺陷的机制——由于（a）增殖神经干细胞的命运的变化和（b）它们对增殖的关键调节剂转化生长因子的反应的变化。