DNA甲基化在DEHP诱发隐睾过程中的调控及干预研究

项目名称： DNA甲基化在DEHP诱发隐睾过程中的调控及干预研究

项目编号： No.30872706

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 魏光辉

作者单位： 重庆医科大学

项目金额： 32万元

中文摘要： 目的：研究DNA甲基化修饰与DEHP诱发隐睾的相关性，为生物制药靶位选择及临床有效干预隐睾发生，提高我国人口素质，提供科学依据。 方法：将DEHP在胎鼠性腺发育的关键时期作用于孕鼠和相应Leydig 细胞，利用MSAP和HPLC法分别检测胎鼠睾丸组织和Leydig细胞基因组甲基化水平；MS-PCR检测INSL3的基因甲基化程度；qPCR检测DNMTs和INSL3表达水平。 结果：正常对照组和玉米油组睾丸及睾丸引带发育正常，DEHP 组睾丸下降不足，睾丸引带发育不良。DEHP 实验组小鼠基因DNA 甲基化的水平高于正常组小鼠基因DNA 甲基化水平；三种主要的DNA 甲基化转移酶在DEHP 实验组表达均较对照组高；DEHP实验组睾丸组织INSL3 的表达量较正常对照组和玉米油组低。 结论：环境内分泌干扰物DEHP通过影响三种甲基化转移酶的表达而导致基因组DNA甲基化水平升高和INSL3基因CpG异常甲基化，从而抑制睾丸下降过程中包括关键因子（INSL3）的表达，导致隐睾的发生。DNA甲基化等表观遗传调控在隐睾的发生、发展中具有重要的作用，表观遗传修饰异常可能是DEHP诱发隐睾的分子机制之一

中文关键词： 隐睾；DEHP；DNA 甲基化；表观遗传调控

英文摘要： OBJECTIVE: To investigate epigenetic changes (specifically, DNA methylation) and its impact on gene expression in cryptorchidism mice induced by maternal exposure to Di-2-(ethylhexyl) phthalate (DEHP). METHODS: The genome-wide DNA methylation patterns were detected by methylation sensitive amplification polymorphism（MSAP）and High-performance liquid chromatography (HPLC),respectively,and the status of methylation of CpG islands in INSL3 gene was analyzed using methylation specific PCR(MS-PCR).Expression levels of the DNA methyhransferases and INSL3 were examined by Quantitative real-time PCR (qPCR). RESULTS: The average incidence of DNA methylation and the expression of DNA methyhransferase were higer in the DEHP exposed mice. The methylated CpG islands in the first exon of INSL3 were merely noted in cryptorchid mice.The Ievels of INSL3 mRNA reduced significantly in cryptorehid mice． CONCLUSION: Hypermethylation of CpG islands in the first exon of INSL3 is probably responsible for low INSL3 expression in cryptorchid mice. Changes in DNA methylation may play an important role in the manifestation of cryptorchidism caused by environmental factors such as maternal exposure to DEHP, which may be one possible mechanism of DEHP-mediated testicular toxicity.

英文关键词： Cryptorchidism; DEHP; DNA methylation; epigenetic regulation