Ethanol effects on retinoic acid function in embryo hippocampus

乙醇对胚胎海马视黄酸功能的影响

• 批准号: 8006507
• 负责人: JOSEPH L NAPOLI
• 金额: $ 34万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-20 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8006507
• 关键词: Adult; Affect; Alcohol consumption; Alcohol dehydrogenase; Alcohols; All-Trans-Retinol; Area; Biological; Biological Assay; Blood alcohol level measurement; Brain; Brain region; Calories; Cerebellum; Chronic; Cognitive; Development; Embryo; Embryonic Development; Ethanol; Ethanol toxicity; Fetal Alcohol Syndrome; Gene Expression; Genetic Transcription; Genomics; Growth; Hippocampus (Brain); Hormonal; Intake; Knockout Mice; Learning; Life; Liver; Metabolism; Mus; Neuraxis; Neurons; Outcome; Pathology; Pathway interactions; Physiological; Process; Regulation; Retinoids; Sampling; Short-Term Memory; Signal Transduction; Staging; Testing; Testis; Tissues; Translations; Tretinoin; Use of New Techniques; Vitamin A; Work; alcohol effect; alcohol exposure; alcohol response; chronic alcohol ingestion; feeding; in vivo; insight; liquid chromatography mass spectrometry; nervous system development; neurogenesis; problem drinker

DESCRIPTION (provided by applicant): This project aims to determine the effects of chronic ethanol ingestion by dams on the concentration and function of atRA (all-trans-retinoic acid) in the embryo hippocampus during normal vitamin A nutriture, using new techniques for quantifying atRA and new insights into retinoid function in the hippocampus. The effects of ethanol on retinoid metabolism and function are poorly understood. The notion persists that ethanol inhibits bioactivation of retinol into atRA, but has not been tested directly in vivo during normal vitamin A nutriture. To test this premise, we developed an LC/MS/MS assay capable of quantifying atRA in specific brain areas. We determined during normal vitamin A nutriture that chronic ethanol exposure (36% of calories for 1 month) increases atRA in the adult mouse cortex (2-fold) and hippocampus (20-fold), without affecting other brain areas. Chronic ethanol exposure also increases atRA in the testis, but does not change atRA in several other mouse retinoid-target tissues. Chronic ethanol fed to dams starting e13 increases embryo atRA in the cortex (up to 50-fold) and the hippocampus (up to 20-fold), depending on blood alcohol content, quantified on e19. Emerging insight indicates that atRA affects learning and cognitive ability, besides nervous system development and neuron specification. Because excessive atRA produces teratogenic CNS effects, and the hippocampus relies on retinoid signaling to establish short-term memory, super physiological concentrations of atRA could contribute to ethanol toxicity, including fetal alcohol syndrome. We will test the hypothesis that ethanol-induced increases in embryo hippocampus atRA contributes to ethanol toxicity. Each aim will determine the effects of dam ethanol ingestion on embryo hippocampus retinoid concentrations and/or function. Wild type and CrbpI-null mice will be evaluated, because ethanol does not increase atRA in hippocampus of CrbpI-null mice. Aim 1 will determine retinoid concentrations in the embryo hippocampus during development. We will focus on e13 to e18 because hippocampus begins developing between e13-e15 and concludes in the CA1 region by e18. Aim 2 will test whether dam ethanol ingestion alters embryo atRA-regulated gene expression (transcription and translation). Aim 3 will test whether ethanol and/or increased atRA affect neurogenesis in the developing hippocampus. Aim 4 will test chronic ethanol effects on atRA-induced dendritic growth. We propose to answer: 1) what are the effects of chronic ethanol ingestion by dams on concentrations of atRA in the embryo hippocampus during normal vitamin A nutriture; 2) do ethanol- induced changes in atRA affect atRA-regulated transcription and translation, atRA processes as a whole (pathway and principle component analysis), or atRA-stimulated dendritic growth or neurogenesis? Even if the outcome reveals the impact of ethanol on atRA is not a major mechanism of its pathology, these studies will provide new insight into mechanisms of ethanol toxicity and retinoid function, and should influence approaches to treating alcoholics. PUBLIC HEALTH RELEVANCE: Vitamin A is essential for vertebrate life, because it is necessary for embryonic development, regulation of metabolism and function of the central nervous system, among many other functions. Alcohol (ethanol) ingestion causes severe depletion of vitamin A storage in the liver, and has been postulated to inhibit activation of vitamin A into its hormonal form, all-trans-retinoic acid (atRA). This project seeks to understand how chronic ethanol ingestion affects the concentrations of atRA in tissues during normal dietary vitamin A intake in the hippocampus area of the brain (the area needed to develop short-term memory), and to determine the effects of ethanol on atRA function in the hippocapus.

描述（由申请人提供）：该项目旨在确定母鼠长期摄入乙醇对正常维生素A营养期间胚胎海马中atRA（全反式视黄酸）浓度和功能的影响，采用定量新技术atRA 和对海马类视黄醇功能的新见解。乙醇对类维生素A代谢和功能的影响尚不清楚。人们一直认为乙醇会抑制视黄醇生物活化成 atRA，但尚未在正常维生素 A 营养期间直接进行体内测试。为了测试这个前提，我们开发了一种 LC/MS/MS 检测方法，能够量化特定大脑区域的 atRA。我们确定，在正常维生素 A 营养期间，长期接触乙醇（1 个月热量的 36%）会增加成年小鼠皮质（2 倍）和海马体（20 倍）的 atRA，而不影响其他大脑区域。慢性乙醇暴露也会增加睾丸中的 atRA，但不会改变其他几种小鼠视黄醇靶组织中的 atRA。从 e13 开始向母鼠饲喂慢性乙醇会增加胚胎皮层（高达 50 倍）和海马体（高达 20 倍）的 atRA，具体取决于血液酒精含量（在 e19 上定量）。新的见解表明，除了神经系统发育和神经元规范之外，atRA 还影响学习和认知能力。由于过量的 atRA 会产生致畸的中枢神经系统效应，并且海马依靠类维生素A信号传导来建立短期记忆，因此超生理浓度的 atRA 可能会导致乙醇中毒，包括胎儿酒精综合症。我们将检验乙醇诱导的胚胎海马 RA 增加导致乙醇毒性的假设。每个目标将确定母鼠乙醇摄入对胚胎海马类视黄醇浓度和/或功能的影响。将评估野生型和 CrbpI 缺失小鼠，因为乙醇不会增加 CrbpI 缺失小鼠海马中的 atRA。目标 1 将确定发育过程中胚胎海马体中的类视黄醇浓度。我们将重点关注 e13 到 e18，因为海马体在 e13-e15 之间开始发育，并在 e18 之前在 CA1 区域结束。目标 2 将测试母鼠乙醇摄入是否会改变胚胎 atRA 调节的基因表达（转录和翻译）。目标 3 将测试乙醇和/或增加的 atRA 是否会影响发育中海马体的神经发生。目标 4 将测试慢性乙醇对 atRA 诱导的树突生长的影响。我们建议回答：1）在正常维生素A营养期间，母鼠长期摄入乙醇对胚胎海马中atRA浓度的影响是什么？ 2) 乙醇诱导的 atRA 变化是否会影响 atRA 调节的转录和翻译、atRA 整个过程（途径和主成分分析）或 atRA 刺激的树突生长或神经发生？即使结果表明乙醇对 atRA 的影响并不是其病理学的主要机制，这些研究也将为乙醇毒性和类维生素A功能的机制提供新的见解，并应影响治疗酗酒者的方法。 公共健康相关性：维生素 A 对于脊椎动物的生命至关重要，因为它对于胚胎发育、新陈代谢调节和中枢神经系统功能以及许多其他功能都是必需的。摄入酒精（乙醇）会导致肝脏中储存的维生素 A 严重消耗，并且被认为会抑制维生素 A 活化成激素形式，即全反式视黄酸 (atRA)。该项目旨在了解在大脑海马区（发展短期记忆所需的区域）正常膳食维生素 A 摄入期间，长期摄入乙醇如何影响组织中 atRA 的浓度，并确定乙醇对 atRA 的影响在海马体中发挥作用。