Fetal Alcohol Exposure and Neurodevelopment

胎儿酒精暴露与神经发育

• 批准号: 7865937
• 负责人: Rajesh C Miranda
• 金额: $ 2.62万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-15 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7865937
• 关键词: Address; Adult; Alcohols; Automobile Driving; Biological; Biological Assay; Biological Process; Birth; Blast Cell; Brain; Categories; Cell Maturation; Cell Proliferation; Cell surface; Cells; Cerebrum; Child; Complex; Congenital Abnormality; Coupled; Data; Development; Disease; Dose; Environment; Epigenetic Process; Ethanol; Exhibits; Exposure to; Fetal Alcohol Exposure; Fetal Alcohol Spectrum Disorder; Flow Cytometry; Foundations; Functional RNA; Gene Expression Profile; Genes; Goals; Growth; Heterogeneity; In Vitro; Individual; Lead; Measures; Mediating; MicroRNAs; Microarray Analysis; Microcephaly; Modeling; Neuroepithelial; Neuroepithelial Cells; Neurons; Nuclear Pore Complex; Outcome; Pattern; Perinatal Exposure; Population; Positioning Attribute; Research; Resources; Rest; Reverse Transcriptase Polymerase Chain Reaction; Role; Second Pregnancy Trimester; Shapes; Staging; Stem cells; Supplementation; Technology; Teratogens; Testing; Therapeutic; Therapeutic Agents; Third Pregnancy Trimester; Ventricular; Withdrawal; Work; alcohol consumption during pregnancy; alcohol effect; alcohol exposure; alcohol sensitivity; base; brain malformation; cohort; combinatorial; developmental disease; experience; fetal; gliogenesis; in utero; in vivo; innovation; killings; mRNA Expression; mouse model; nerve stem cell; neurodevelopment; neuroepithelium; neurotoxic; novel; premature; prevent; progenitor; relating to nervous system; research study; stem; technology development

DESCRIPTION (provided by applicant): Alcohol is an important teratogen. Much research has focused on the sensitivity of the third- trimester period of brain development, where ethanol has been shown to be neuro-toxic. However, we know very little about the vulnerability of the second trimester period. The second trimester is important, because during this trimester, fetal neural stem (NSCs) and progenitor (NPCs) cells give rise to most neurons of the adult brain. Previously, we showed that ethanol did not kill fetal cortical NSCs/NPCs. Rather, ethanol induced cell proliferation, but depleted NSCs and NPCs, suggesting that ethanol promoted aberrant NSC maturation. Importantly, ethanol suppressed four microRNAs; small non-coding RNA molecules that control large gene networks to determine cell fate. Our central hypothesis is that ethanol depletes NSCs by driving stem to blast maturation of NSCs. A secondary hypothesis is that microRNAs mediate teratogenic effects of ethanol. We will address three specific aims. (Aim#l) To determine the extent to which ethanol promotes premature cortical neuroepithelial maturation. Our hypotheses are that (a) in utero binge ethanol exposure, during the second trimester period will significantly deplete resident NSCsINPCs and (b) isolated NSCs/NPCs will exhibit aberrant maturation patterns following ethanol exposure. We will test the ethanol- sensitivity of NSC/NPC populations using flow cytometric approaches. (Aim#2) To identify ethanol- sensitive microRNAs and their biological mechanisms. Our hypothesis is that ethanol persistently suppresses microRNAs that promote NSC/NPC renewal. We will use microarray technologies to identify candidate microRNAs, and manipulate levels of these microRNAs, to identify their role in NSC/NPC maturation. (Aim#3) To determine the extent to which ethanol-sensitive microRNAs prevent or reverse the effects of ethanol on fetal NSCs/NPCs. Our hypothesis is that microRNA supplementation will prevent and reverse ethanol's effects on NSC/NPC renewal and maturation. Cell biological approaches and mRNA expression analyses and will be used to assess the capacity of ethanol-regulated microRNAs to reverse or prevent the effects of prior ethanol exposure. At the end of the project period, we expect to have identified sensitive NSC/NPC populations, critical second-trimester periods of vulnerability to ethanol, and specific microRNAs and microRNA- mediated mechanisms that are persistently altered by ethanol. These outcomes will be significant because they are expected to provide the foundations for developing therapeutic strategies to manage the persistent neural effects of a leading teratogen. PUBLIC HELTH RELEVANCE Alcohol is a potent teratogen. Alcohol consumption during pregnancy can lead to a stereotypic spectrum of disorders in children, called the `Fetal Alcohol Spectrum Disorders' or FASD. At the neuroanatomical level, birth defects can include microencephaly and brain malformations. Much research has focused on the sensitivity of the third-trimester period of brain development, where ethanol has been shown to be neurotoxic. However, we know very little about the vulnerability of the second trimester period. The second trimester is important, because during this trimester, neuroepithelial cells of the ventricular walls give birth to millions of new neurons, creating a cellular framework for the rest of neural development. Previously, we showed that fetal cerebral cortical neuroepithelial cells did not die when exposed to ethanol. Rather, ethanol induced cell proliferation, while depleting cells expressing neural stem (NSC) and progenitor cell (NPC) markers. This proposal will test two hypotheses, that ethanol depletes stem and progenitor cells by driving stem to blast maturation of NSCs, and that the effects of ethanol are mediated by, and consequently, can be reversed by microRNAs. At the end of the project period, we expect to have identified sensitive NSC/NPC populations, critical second-trimester periods of vulnerability to ethanol, and specific microRNAs and microRNA-mediated mechanisms that are persistently altered by ethanol. These outcomes will be significant because they are expected to provide the foundations for developing therapeutic strategies to manage the persistent neural effects of a leading teratogen.

描述（由申请人提供）：酒精是一种重要的致畸剂。许多研究都集中在大脑发育的妊娠晚期的敏感性上，其中乙醇已被证明具有神经毒性。然而，我们对妊娠中期的脆弱性知之甚少。妊娠中期很重要，因为在此期间，胎儿神经干细胞 (NSC) 和祖细胞 (NPC) 会产生成人大脑的大多数神经元。此前，我们证明乙醇不会杀死胎儿皮质 NSC/NPC。相反，乙醇诱导细胞增殖，但耗尽了 NSC 和 NPC，这表明乙醇促进了异常 NSC 的成熟。重要的是，乙醇抑制了四种 microRNA；控制大型基因网络以确定细胞命运的小非编码 RNA 分子。我们的中心假设是，乙醇通过驱动 NSC 的干细胞成熟来消耗 NSCs。第二个假设是 microRNA 介导乙醇的致畸作用。我们将实现三个具体目标。 （目标#1）确定乙醇促进皮质神经上皮过早成熟的程度。我们的假设是（a）在子宫内暴饮乙醇暴露，在妊娠中期将显着消耗驻留的 NSCsINPCs 和（b）分离的 NSCs/NPCs 在乙醇暴露后将表现出异常的成熟模式。我们将使用流式细胞术方法测试 NSC/NPC 群体的乙醇敏感性。 （目标#2）识别乙醇敏感的 microRNA 及其生物学机制。我们的假设是乙醇持续抑制促进 NSC/NPC 更新的 microRNA。我们将使用微阵列技术来识别候选 microRNA，并操纵这些 microRNA 的水平，以确定它们在 NSC/NPC 成熟中的作用。 （目标#3）确定乙醇敏感的 microRNA 在多大程度上阻止或逆转乙醇对胎儿 NSC/NPC 的影响。我们的假设是，补充 microRNA 将预防和逆转乙醇对 NSC/NPC 更新和成熟的影响。细胞生物学方法和 mRNA 表达分析将用于评估乙醇调节的 microRNA 逆转或防止先前乙醇暴露影响的能力。在项目期结束时，我们期望确定敏感的 NSC/NPC 人群、易受乙醇影响的关键妊娠中期时期，以及乙醇持续改变的特定 microRNA 和 microRNA 介导的机制。这些结果将具有重要意义，因为它们有望为制定治疗策略提供基础，以管理主要致畸剂的持续神经效应。公共健康相关性 酒精是一种强效致畸剂。怀孕期间饮酒可能会导致儿童出现一系列刻板的疾病，称为“胎儿酒精谱系障碍”或 FASD。在神经解剖学水平上，出生缺陷可包括小脑畸形和脑畸形。许多研究都集中在大脑发育的妊娠晚期的敏感性上，乙醇已被证明具有神经毒性。然而，我们对妊娠中期的脆弱性知之甚少。妊娠中期很重要，因为在这个妊娠期，心室壁的神经上皮细胞会产生数百万个新神经元，为神经发育的其余部分创建细胞框架。此前，我们发现胎儿大脑皮质神经上皮细胞在接触乙醇时不会死亡。相反，乙醇诱导细胞增殖，同时消耗表达神经干（NSC）和祖细胞（NPC）标记的细胞。该提案将测试两个假设，即乙醇通过驱动 NSC 的干细胞成熟来消耗干细胞和祖细胞，以及乙醇的作用是由 microRNA 介导的，因此可以被 microRNA 逆转。在项目期结束时，我们期望确定敏感的 NSC/NPC 人群、易受乙醇影响的关键妊娠中期时期，以及乙醇持续改变的特定 microRNA 和 microRNA 介导的机制。这些结果将具有重要意义，因为它们有望为制定治疗策略提供基础，以管理主要致畸剂的持续神经效应。