AGE-induced Phenotype of the Retinal Pigment Epithelium

描述(申请人提供)：虽然一些基因已经 推测与老年性黄斑变性(AMD)有关， 美国老年人致盲的主要原因：一项综合性的研究 视网膜色素上皮(RPE)的活体表型 未知。RPE mRNA表型的测定可以确定这些基因 对AMD的发展至关重要，识别疾病的标志物，并导致 新的预防和治疗策略。Bruch膜上的基底物 是发生在RPE退化之前的早期可识别的变化 是AMD的组织病理学标志物。最近，我们实验室鉴定出 晚期糖基化终末产物(AGEs)的年龄相关性积累 Bruch膜和基底层。年龄是在 糖或其他前体之间的一系列非酶反应，以及 能改变多种细胞表型的长寿蛋白质。我们的 实验室最近还表明，年龄会改变基因的表达。 参与RPE细胞的基质调节、细胞极性和细胞凋亡。我们的 长期目标是确定健康人群中广泛的RPE的mRNA表型 和AMD，这将反过来为AMD的发病机制提供见解。 具体地说，我们希望定义该表型的组成部分，即 受年龄的制约。我们假设在基底沉积物中存在年龄 负责RPE细胞表型的转换，这与 随着基质调节、RPE细胞极性和细胞凋亡的改变。至 为了验证这一假设，我们提出了三个问题：1.黄斑组织的mRNA表型 结论：1.视网膜色素上皮细胞覆盖基底膜与正常Bruchs膜不同。 AGE修饰的基质是否在体外诱导RPE mRNA的一个亚型 覆盖在基底沉积物上的RPE细胞表达的表型是什么？3.是一种 受体介导的AGE诱导的RPE细胞mRNA表型亚群 高级糖基化终端产品？为了回答这些问题，我们将使用 激光捕获显微切割法从组织中获取RPE细胞纯样本 采用基因芯片技术对标本进行mRNA表型分析。我们还将利用 体外年龄-矩阵系统来确定哪些基因亚集受 很久以前了。本项目希望建立广泛的RPE的mRNA表型。 健康和AMD，并定义了由年龄诱导的基因子集。

DESCRIPTION (provided by applicant): While a number of genes have been postulated to be involved in age-related macular degeneration (AMD), the leading cause of blindness among the elderly in the US, a comprehensive mRNA phenotype of the retinal pigment epithelium (RPE) in vivo is at present unknown. Determination of an RPE mRNA phenotype could identify the genes critical to the development of AMD, identify markers of disease, and lead to new preventative and treatment strategies. Basal deposits in Bruch's membrane are an early recognizable change that occur prior to degeneration of the RPE and are a histopathological marker for AMD. Recently, our laboratory identified an age-dependent accumulation of advanced glycation end products (AGEs) in Bruch's membrane and basal deposits. AGEs are structures formed during the series of nonenzymatic reactions between sugars or other precursors, and long-lived proteins that alter the phenotype of a variety of cell types. Our laboratory has also recently shown that AGEs alter the expression of genes involved in matrix regulation, cell polarity, and apoptosis in RPE cells. Our long term goal is to define an extensive mRNA phenotype of the RPE in health and AMD which will in turn, yield insights into the pathogenesis of AMD. Specifically, we want to define the component of that phenotype which is regulated by AGEs. We hypothesize that the presence of AGEs in basal deposits is responsible for a switch in the phenotype of RPE cells that is consistent with alterations in matrix regulation, RPE cell polarity, and apoptosis. To test this hypothesis we ask 3 questions: 1. Are the mRNA phenotypes of macular RPE cells overlying basal deposits and normal Bruch's membrane different? 2. Does AGE modified matrix induce an RPE mRNA phenotype in vitro that is a subset of the phenotype expressed by RPE cells overlying basal deposits? 3. Is a subset of the AGE induced mRNA phenotype of RPE cells mediated by the Receptor for Advanced Glycation End products? To answer these questions we will use laser capture microdissection to obtain pure samples of RPE cells from tissue specimens for mRNA phenotyping by microarray analysis. We will also utilize an in vitro AGE-matrix system to determine what subset of genes is regulated by AGEs. This project hopes to establish an extensive mRNA phenotype of the RPE in both health and AMD, and define a subset of genes induced by AGEs.