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第三个三个月期间的敏感性上，乙醇已被证明是神经毒性的。然而，我们对孕中期的脆弱性知之甚少。第二个三个月是重要的，因为在这个三个月期间，胎儿神经干细胞（NSC）和祖细胞（NPC）细胞产生成人大脑的大多数神经元。以前，我们表明，乙醇不会杀死胎儿皮质神经干细胞/神经祖细胞。相反，乙醇诱导细胞增殖，但耗尽神经干细胞和神经前体细胞，表明乙醇促进异常神经干细胞成熟。重要的是，乙醇抑制了四种microRNA;控制大型基因网络以决定细胞命运的小非编码RNA分子。我们的中心假设是，乙醇耗尽神经干细胞驱动干细胞的原始细胞成熟。第二个假设是microRNA介导乙醇的致畸作用。我们将讨论三个具体目标。(Aim#l）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）在子宫内酒精暴露，在第二个三个月期间将显着耗尽居民NSCsINPC和（B）分离的NSCs/NPC将表现出异常的成熟模式后，乙醇暴露。我们将使用流式细胞仪方法测试NSC/NPC群体的乙醇敏感性。(Aim#2）鉴定乙醇敏感的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鉴定候选microRNA，并操纵这些microRNA的水平，以确定它们在NSC/NPC成熟中的作用。(Aim#3）确定乙醇敏感性microRNA预防或逆转乙醇对胎儿NSC/NPC的影响的程度。我们的假设是，microRNA补充剂将防止和逆转乙醇对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逆转或预防先前乙醇暴露影响的能力。在项目期结束时，我们预计已经确定了敏感的NSC/NPC人群，对乙醇敏感的关键中期妊娠期，以及被乙醇持续改变的特定microRNA和microRNA介导的机制。这些结果将是重要的，因为它们有望为开发治疗策略提供基础，以管理主要致畸剂的持续神经效应。公共卫生相关性酒精是一种强有力的致畸剂。怀孕期间饮酒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，出生缺陷可以包括微脑畸形和脑畸形。许多研究都集中在大脑发育的第三个三个月期间的敏感性上，乙醇已被证明具有神经毒性。然而，我们对孕中期的脆弱性知之甚少。第二个三个月很重要，因为在这个三个月期间，心室壁的神经上皮细胞产生了数百万个新的神经元，为神经发育的其余部分创造了细胞框架。以前，我们发现胎儿大脑皮质神经上皮细胞暴露于乙醇时不会死亡。相反，乙醇诱导细胞增殖，同时耗尽表达神经干细胞（NSC）和祖细胞（NPC）标志物的细胞。该提案将测试两个假设，即乙醇通过驱动NSC的干细胞到胚细胞成熟来消耗干细胞和祖细胞，以及乙醇的作用由microRNA介导，因此可以被microRNA逆转。在项目期结束时，我们预计已经确定了敏感的NSC/NPC人群，对乙醇敏感的关键中期妊娠期，以及特定的microRNA和microRNA介导的机制，这些机制会被乙醇持续改变。这些结果将是重要的，因为它们有望为开发治疗策略提供基础，以管理主要致畸剂的持续神经效应。