ETHANOL REGULATION OF GENE EXPRESSION IN ASTROCYTES

人类产前酒精暴露可导致胎儿酒精 综合征（FAS）或胎儿酒精效应（FAE）。暴露于乙醇 子宫是美国智力迟钝的主要已知原因 States.产前酒精的医学和行为后果 暴露包括智商低下，发育迟缓，注意力 缺陷、小头畸形、神经系统异常和面部 畸形学 乙醇对细胞的主要作用 神经系统的发展是未知的。 一般假设 指导这项工作的是，乙醇通过直接破坏CNS发育， 改变特定基因的正常表达， 一系列的发展后果的特点FAS。这 建议描述了一个可能的模型系统，用于测试这一点 假说.尽管神经胶质细胞参与CNS的重要性 他们在FAS病因学中的潜在作用已经被发现， 基本上被忽视了。 有证据表明，短暂接触 乙醇在大脑发育期间相当于第三次 人类三个月会导致稳态 胶质细胞酸性蛋白（GFAP）mRNA和蛋白水平 大鼠大脑皮层实验还表明， 这些增加可能是乙醇对星形胶质细胞的直接影响， 由于皮质中乙醇暴露的相似剂量和持续时间 星形胶质细胞原代培养物导致GFAP的相当增加 表情这表明，一个重要的潜在机制， 乙醇诱导的GFAP增加涉及调节 星形胶质细胞基因表达的转录调控。 具体 本建议的目的是（1）描述时间过程和剂量- 乙醇对GFAP mRNA稳态水平的影响 和蛋白质。这些实验的结果将评估 这两种模型中星形胶质细胞反应的相似性，并将定义 具体目标2中描述的实验条件，和（2）至 直接测定乙醇对GFAP率的影响 体外和体内转录。机制的确定 乙醇引起GFAP基因调节的这些变化， 提供了重要的见解（i）乙醇对神经胶质细胞的作用， 细胞，（ii）乙醇可以调节基因表达的方式， 一般情况，以及（iii）生理和发育情况 在这种情况下某些细胞对乙醇很敏感结果进行 实验将成为未来实验的基础，这些实验对于 这项工作的长期目标，以描述其背后的机制 乙醇诱导的星形胶质细胞基因表达的变化， 评估这些变化在FAS相关CNS病因学中的作用 异常

Prenatal alcohol exposure in humans can result in fetal alcohol syndrome (FAS) or fetal alcohol effects (FAE). Exposure to ethanol in utero is the leading known cause of mental retardation in the United States. The medical and behavioral consequences of prenatal ethanol exposure include depressed IQ, developmental delays, attentional deficits, microcephaly, neurologic abnormalities, and facial dysmorphology. The primary action(s) of ethanol on cells of the developing nervous system are not known. The general hypothesis guiding this work is that ethanol disrupts CNS development by directly altering the normal expression of specific genes, resulting in a cascade of developmental consequences that characterize FAS. This proposal describes one possible model system for testing this hypothesis. Despite the importance of glial cell participation in CNS development their potential role in the etiology of FAS has been largely overlooked. Evidence is presented that brief exposure to ethanol during a period of brain development equivalent to the third human trimester causes a large transient increase in steady-state levels of glial fibrillary acidic protein (GFAP) mRNA and protein in rat cerebral cortex. Experiments are also presented that demonstrate that these increases may be a direct effect of ethanol on astrocytes since a similar dose and duration of ethanol exposure in cortical astrocyte primary cultures results in a comparable increase in GFAP expression. This suggests that an important potential mechanism for ethanol-induced increases in GFAP involves the modulation of transcriptional regulation of astrocyte gene expression. The specific aims o this proposal are (1) to describe the time-course and dose- dependence of ethanol's effects on steady-state levels of GFAP mRNA and protein. The results of these experiments will assess the similarity of astrocyte responses in these two models, and will define conditions for experiments described in specific aim 2, and (2) to directly determine the effect of ethanol on the rate of GFAP transcription in vitro and in vivo. Identification of the mechanism(s) by which ethanol causes these changes in GFAP gene regulation will provide important insights into (i) the action of ethanol on glial cells, (ii) the ways in which ethanol can modulate gene expression in general, and (iii) the physiologic and developmental circumstances under which certain cells are vulnerable to ethanol. Results of these experiments will form the foundation for future experiments central to the long-term goal of this work, to describe the mechanisms underlying ethanol-induced changes in gene expression in astrocytes, and to assess the role of these changes in the etiology of FAS-related CNS abnormalities.