MECHANISMS OF ETHANOL INDUCED TERATOGENICITY

描述（由申请人提供）：本研究项目旨在提高我们的 了解酒精诱导的糖尿病的机制和分子病理学， 畸形发生。它跟进我们以前的识别选定区域的大脑，耳，视原始作为目标的乙醇诱导的细胞凋亡和随后的出生缺陷，我们正在进行的微阵列分析的结果，以及其他人对这一领域的重大贡献。专注于小鼠的发育阶段，对应于人类胚胎发生的第3-6周，并采用原位杂交，我们将测试以下假设：暴露于乙醇后数小时内，胚胎大脑，眼睛和内耳中发生模式基因的异常表达;这些变化预示着随后的畸形发生。为了阐明致病序列，改变的图案是可检测的时间将比较，其中细胞凋亡可以最初被确定。利用急性乙醇暴露范例、全胚胎培养和激光共聚焦成像，将有助于分析小鼠胚胎发生中的时间和区域特异性改变。认识到乙醇暴露可以干扰类维生素A代谢和视黄酸（RA）调节基因表达，我们还将研究这一假设，减少RA依赖的基因信号的基础乙醇的致畸性。在这项工作中，我们将比较基因表达模式， 以及类维生素A缺乏（BMS 493处理）和乙醇暴露的小鼠胚胎发育中的脑、眼和内部的细胞凋亡模式，并测试RA的改善潜力。此外，我们建议进行体外和体内调查，以测试的假设，改变遗传（特别是音刺猬）信号源于乙醇诱导的RA缺乏症将加剧减少信号后，胆固醇降低。这些实验将利用乙醇（AY 9944）和遗传（7脱氢胆固醇还原酶基因修饰）诱导的胆固醇缺乏症，两者均产生与乙醇引起的畸形一致的畸形。 这项工作有望提供重要的新数据，相对于可能影响敏感性的因素，乙醇诱导的致畸作用在人群中。它还将为类似的分析奠定基础，用于跟踪其他发育阶段和脆弱组织。

DESCRIPTION (provided by applicant): This research project is designed to increase our understanding of the mechanisms and molecular pathology underlying alcohol-induced dysmorphogenesis. It follows up on our previous identification of selected regions of the brain, otic, and optic primordial as targets of ethanol-induced apoptosis and subsequent birth defects, results of our ongoing microarray analyses, and significant contributions to this field by others. Focusing on Developmental stages in mice that correspond to weeks 3-6 of human embryogenesis and employing in situ hybridization, we will test the hypothesis that within hours following exposure to ethanol, abnormal expression of patterning genes occurs in the embryonic brain, eye and inner ear; changes that presage subsequent dysmorphogenesis. To elucidate pathogenic sequences, the time by which altered patterning is detectable will be compared to that for which apoptosis can initially be identified. Analyses of temporally and regionally-specific alterations in mouse embryogenesis, will be facilitated by utilization of an acute ethanol exposure paradigm, whole embryo culture, and laser confocal imaging. Recognizing that ethanol exposure can interfere with retinoid metabolism and that retinoic acid (RA) regulates gene expression; we will also examine the hypothesis that diminishing RA-dependent gene signaling underlies ethanol's teratogenicity. For this work, we will compare gene expression patterns and patterns of apoptosis in the developing brain, eye and innerear of retinoid-deficient (BMS493-treated)and ethanol-exposed mouse embryos and test RA's ameliorative potential. Additionally, we propose to conduct in vitro and in vivo investigations to test the hypothesis that altered genetic (esp. sonic hedgehog) signaling stemming from ethanol-induced RA deficiency will exacerbate diminished signaling subsequent to cholesterol reduction. These experiments will utilize both pharmacologically (AY9944) and genetically (7 dehydrocholestrol reductase gene modification) - induced cholesterol deficiency, both of which yield malformations consistent with those caused by ethanol. This work is expected to provide important new data relative to factors that may influence sensitivity to ethanol-induced teratogenesis in human populations. It will also establish a foundation for similar analyses to be utilized in following up on other developmental stages and vulnerable tissues.