抗氧化应激相关基因DNA甲基化在高度近视并发性白内障发病中的作用和机制研究

项目名称： 抗氧化应激相关基因DNA甲基化在高度近视并发性白内障发病中的作用和机制研究

项目编号： No.81470613

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 竺向佳

作者单位： 复旦大学

项目金额： 73万元

中文摘要： 高度近视并发性白内障（HMC）是高致盲风险的白内障类型，已占我国白内障手术量的30%，且比例逐年上升，但其发病机制的研究却一直匮乏。我们前期研究发现HMC极易并发手术风险极高的黑核，而DNA甲基化增加导致抗氧化应激基因之一的CRYAA与晶状体结构蛋白表达下降加速了HMC发病；为进一步明确HMC中其他抗氧化应激相关基因的改变，我们进行了高通量DNA甲基化组测序及表达谱芯片分析，初步筛选了HMC较年龄相关性白内障晶状体中DNA甲基化明显升高的4组抗氧化应激相关基因：Nrf2/SOD1/TFAP2C/GSTP1。本研究拟用焦磷酸测序大样本量验证HMC中这些基因的DNA甲基化状态及表达，观察其甲基化升高后与上游转录相关因子的结合及下游相关通路的改变，并评估DNA甲基化抑制剂对其的干预效应。旨在较全面地阐明抗氧化应激相关基因DNA甲基化对HMC的作用和机制，为早期非手术干预提供依据。

中文关键词： 白内障；高度近视；DNA甲基化；氧化应激；基因

英文摘要： High-myopic cataract (HMC), accounting for 30% of cataract surgery in China recently, is a type of complicated cataract with great risk of blindness. Its proportion is increasing every year. However, the study of HMC-associated pathogenesis has been quite scarce. Our previous study found that compared to patients with age-related cataract (ARC), high myopia was associated with a significantly greater risk of dark nucleus, which multiplied the difficulties during cataract surgery. And such dark nucleus might be caused by hypermethylation of anti-oxidative gene (CRYAA) promoter and decreasing of lens structural protein expression in the high-myopic eyes. However, it might be only part of the story. In order to further clarify the changes of other anti-oxidative related genes in HMC eyes, we then carried out preliminary screening with high-throughput DNA methylation sequencing and microarray analysis in the HMC lenses, and 4 anti-oxidative related genes (Nrf2/SOD1/TFAP2C/GSTP1) with significantly elevated DNA methylation status comparing to ARC cases were identified. In the current study, we plan to carry out pyrosequencing in a large sample to verify the DNA methylation status and expression of the 4 selected genes in HMC cases. We will also analyze the binding of the selected genes with upstream transcription related factors and the changes of their downstream pathways after DNA hypermethylation. Finally, we will validate the intervention effects of DNA methylation inhibitor on the 4 selected genes in HMC. Based on these studies, we manage to clarify the role and mechanisms of DNA methylation of anti-oxidative related genes in the pathogenesis of HMC, and to provide the basis for its early non-surgical intervention in the future.

英文关键词： cataract;high myopia;DNA methylation;oxidative stress;gene