Analysis of Genomic and Proteomic Changes in Glia That Lead To Hydrocephalus

描述(申请人提供)：本研究项目的目标是确定治疗脑积水的治疗靶点。脑积水(HC)是一种主要的临床疾病，影响到美国约0.1%的人口，每年给美国造成超过10亿美元的损失。目前，还没有基于药物的治疗方法来治疗HC。所有病例均采用分流术降低脑室压。超过30%的新分流装置在第一年失败，超过三分之二的新分流装置在十年内失败。此外，接受分流术的HC患者中有2.7%死于与手术相关的并发症。尽管有这些统计数据，但50多年来治疗HC的一般方法并没有显著改变。在治疗HC方面缺乏进展在很大程度上是由于HC的原因是多因素的，既涉及基因突变，也涉及环境侮辱。此外，主要负责HC发展的细胞基础和分子途径在很大程度上仍不清楚。已经建立了许多HC的动物模型；然而，这些动物模型中的大多数除了HC之外还有多种病理机制。因此，很难梳理出在HC发生发展中重要的细胞机制。对人类胎儿的研究，包括由不同突变引起的HC，表明在大多数先天性HC病例中，室管膜剥离伴随着Sylvius导水管的关闭。这些研究和其他研究支持这一假说，即大多数类型的HC的早期事件是室管膜细胞的丢失或功能障碍，从而导致脑脊液的主要出口通路--Sylvius导水管的关闭。我们提出了两组实验。首先，我们建议使用一个新开发的HC小鼠模型来识别在显性HC发生之前室管膜细胞中发生的基因组和蛋白质组变化。这种新的HC模型，被称为Ro1HC，是基于GI偶联的GPCR在表达胶质纤维酸性蛋白(GFAP)的细胞中的过度表达。我们使用四环素诱导的调控系统制作了这个模型，该系统使我们能够控制表达GFAP的细胞中基因表达的时间和水平。重要的是，在这些小鼠身上观察到的病理与在人类HC中观察到的非常相似，包括早期室管膜剥离和随后的Sylvius导水管关闭。其次，我们建议在体外确定HC的相关性，以用于筛选能够干扰HC的发展或维持的小分子。 公共卫生相关性：这项赠款计划的目标是确定导致脑积水的关键机制，并开发可用于筛选能够治疗这种疾病的小分子的脑积水的体外相关性。脑积水是一种主要的临床疾病，影响到美国约0.1%的人口，每年给美国造成超过10亿美元的损失。目前治疗脑积水的唯一方法是通过手术植入分流术来缓解脑室内压力。超过30%的新分流术在第一年失败，超过三分之二的分流术在十年内失败；2.7%接受分流术的脑积水患者死于与外科手术相关的并发症。

DESCRIPTION (provided by applicant):The goal of this research project is to identify therapeutic targets for the treatment of hydrocephalus. Hydrocephalus (HC) is a major clinical disorder affecting ~0.1% of the population in the United States and costing this country more than a billion dollars annually. At this time, there are no drug based therapeutic approaches for treating HC. All cases of HC are treated using shunts to decrease ventricular pressure. More than 30% of all new shunts fail in the first year and more than two thirds of new shunts fail during a ten year period. Further, 2.7 % of HC patients receiving shunts die from complications associated with the surgical procedure. In spite of these statistics, the general approach to treating HC has not changed significantly in over fifty years. The lack of progress in the treatment of HC stems, in large part, from the fact that the causes of HC are multifactorial involving both genetic mutations and environmental insults. Further, the cellular basis and molecular pathways primarily responsible for the development of HC remain largely unknown. A number of animal models of HC have been developed; however, most of these have multiple pathologies in addition to HC. As a result, it has been difficult to sort out cellular mechanisms important in the development of HC. Studies with human fetuses, which include HC arising from different mutations, suggest that ependymal denudation followed by closure of the aqueduct of Sylvius occurs in most cases of congenital HC. These and other studies support the hypothesis that an early event occurring in most forms of HC is the loss or dysfunction of ventricular ependymal cells and consequent closure of the aqueduct of Sylvius, the primary exit pathway for brain CSF. We propose two sets of experiments. First, we propose to use a newly developed mouse model of HC to identify genomic and proteomic changes that occur in ependymal cells prior to the development of overt HC. This new model of HC, referred to as Ro1HC, is based on the over expression of a Gi coupled GPCR in cells expressing glial fibrillary acidic protein (GFAP). We made this model using a tetracycline inducible regulatory system that enables us to control the timing and level of gene expression in cells expressing GFAP. Importantly, pathology observed in these mice closely resembles that observed in human HC, including the early ependymal denudation and subsequent closure of the aqueduct of Sylvius. Second, we propose to identify in vitro correlates of HC that can be used to screen for small molecules capable of interfering with the development or maintenance of HC. PUBLIC HEALTH RELEVANCE: The goal of this grant proposal is to identify the key mechanisms that lead to hydrocephalus as well as develop an in vitro correlate of hydrocephalus that can be used to screen for small molecules capable of treating this disease. Hydrocephalus is a major clinical disorder affecting ~0.1% of the population in the United States and costing this country more than a billion dollars annually. The only current treatment of hydrocephalus is based on surgically-implanting shunts designed to relieve intraventricular pressure. More than 30% of all new shunts fail in the first year and more than two thirds of shunts fail within ten years; 2.7% of hydrocephalic patients receiving shunts die from complications associated with the surgical procedure.