摘要
目的研究环境内分泌干扰物邻苯二甲酸二(2-乙基已基)酯[Di—(2-ethylhexy)phthalate,DEHP]作用于孕鼠后,胎鼠睾丸组织基因组DNA甲基化水平的变化及3种DNA甲基化转移酶的表达情况;探讨DEHP所致表观遗传修饰改变在睾丸下降过程中的作用。方法妊娠昆明小鼠(KMmice)随机分为3组,即正常对照组、玉米油对照组和DEHP实验组,每组15只。玉米油对照组和DEHP实验组自妊娠第12.5天到妊娠第18.5天分别持续经口予以玉米油和DEHP,用量按每日500mg/kg,正常对照组不予灌药。采用高效液相色谱仪检测基因组DNA甲基化水平,实时荧光定量PCR检测3种DNA甲基化转移酶的表达量。结果正常对照组和玉米油对照组DNA甲基化水平和3种甲基化转移酶的表达均无统计学意义(P〉0.05):DEHP实验组DNA甲基化水平比对照组增高约10%。与对照组相比,差异有显著统计学意义(P〈0.05);实验组3种甲基化转移酶的表达量均比对照组高,与对照组相比,差异有显著统计学意义(Dnmt1,P〈0.05;Dnmt3a,P〈0.01;Dnmt3b,P〈0.05)。结论环境内分泌干扰物DEHP通过影响3种甲基化转移酶的表达而导致基因组DNA甲基化水平升高,从而抑制睾丸下降过程中多种基因的表达,发生隐睾。DNA甲基化等表观遗传学修饰的改变可能是DEHP诱发隐睾的分子机制之一。
Objective To analyze epigenetic (specifically, DNA methylation) and DNA methyltransferases participation in the mechanisms of cryptorebidism only induced by maternal exposure to Di-2-(ethylhexyl) phthalate (DEHP) in mice. Methods KM miees were divided into 3 groups randomly: normal control group, corn oil group and DEHP-exposed group. Corn oil and DEHP [500 mg/ (kg· d)] were administrated respectively to the pregnant mice from gestation day 12.5 (GD12.5) to GD18.5. Testes were excised for analysis at GD19. High-performance liquid chromatography (HPLC) was performed to analyze DNA methylation status. The expression levels of the DNA methyhransferases were examined by Quantitative real-time PCR (qPCR). Results Using HPLC, at GD19, the status of DNA methylation in global DNA was increased significantly in DEHP-treated groups compared with the controls (P 〈 0.05). There were also significant changes in the expression of DNA methyhransferases (Dnmtl ,P 〈 0.05;Dnmt3a,P 〈 0.01 ;Dumt3b,P 〈 0.05). Conclusions These results indicate that changes in DNA methylation may play an important role in the manifestation of cryptorchidism only caused by environmental factors such as maternal exposure to DEHP.
出处
《临床小儿外科杂志》
CAS
2010年第1期21-23,26,共4页
Journal of Clinical Pediatric Surgery
基金
本研究为国家自然科学基金(项目编号:30872706)以及重庆市自然科学基金(项目编号:2007BB5325)资助项目.