氯乙烯对大鼠肝细胞RASSF1A基因DNA甲基化的影响

发布时间：2018-01-21 12:10

本文关键词： 氯乙烯(VC) RASSFA DNA甲基化 mRNA表达　出处：《毒理学杂志》2017年01期 　论文类型：期刊论文

【摘要】：目的通过检测氯乙烯(VC)染毒大鼠肝细胞RASSF1A基因启动子区甲基化的水平及mRNA的表达量,探讨RASSF1A基因在氯乙烯致癌过程中的表观遗传机制。方法选取96只健康雄性SD大鼠,随机分为4组:阴性对照组(0mg/kg)和低剂量(5 mg/kg)、中剂量(25 mg/kg)、高剂量(125 mg/kg)3个氯乙烯染毒组。腹腔注射,隔日染毒,每周3次。每组分别于6、8和12周随机处死8只,取其肝脏。采用甲基化特异性实时荧光定量(QMSP)检测大鼠肝细胞RASSF1A基因启动子区甲基化的水平,采取实时荧光定量(QPCR)测定RASSF1A mRNA表达量的改变。结果染毒6周时,RASSF1A基因启动子区甲基化水平各组间无明显变化,差异无统计学意义(P0.05);但RASSF1A mRNA的表达量随着剂量的增加而升高,且高剂量组、中剂量组与对照组相比,差异有统计学意义(P0.05)。染毒8周时,RASSF1A基因启动子区甲基化水平和mRNA的表达量在各组间差异无统计学意义(P0.05)。染毒12周时,RASSF1A基因启动子区甲基化水平随着染毒剂量的增加而明显升高,高剂量组与其他各组相比,差异有统计学意义(P0.05);mRNA的表达量随着染毒剂量的增加而出现下降,且对照组和低剂量组与高剂量组相比,差异有统计学意义(P0.05)。此外,在高剂量组中,8周时RASSF1A启动子区甲基化水平较6周时低,差异有统计学意义(P0.05),而12周时启动子区甲基化水平较6周时高,且差异有统计学意义(P0.05);mRNA表达量随着染毒时间的延长而下降,且8和12周mRNA表达量与6周时相比,差异有统计学意义(P0.05),在其余各组中,不同染毒时间下RASSF1A甲基化水平及mRNA表达量均未出现统计学差异(P0.05)。结论氯乙烯长期染毒可致大鼠肝细胞RASSF1A基因启动子区甲基化水平的升高,并引起其mRNA的表达量下降,可能参与氯乙烯致癌的表观遗传机制。
[Abstract]:Objective to detect the methylation level of RASSF1A gene promoter and the expression of mRNA in rat hepatocytes exposed to vinyl chloride (VC). To explore the epigenetic mechanism of RASSF1A gene in carcinogenesis of vinyl chloride. Methods 96 healthy male SD rats were selected. They were randomly divided into 4 groups: negative control group (0 mg / kg), low dose (5 mg / kg) and middle dose (25 mg / kg). High dose of 125mg / kg vinyl chloride was injected intraperitoneally three times a week. Eight rats were randomly killed in each group at 6 weeks and 12 weeks respectively. The methylation of the promoter region of RASSF1A gene in rat hepatocytes was detected by methylation specific real-time fluorescence quantitative quantitation (QMSPs). The expression of RASSF1A mRNA was measured by real-time fluorescence quantitative PCR. Results there was no significant change in methylation level of promoter region of RASSF1A gene at 6 weeks after exposure. The difference was not statistically significant (P 0.05). However, the expression of RASSF1A mRNA increased with the increase of dose, and the difference between the high dose group and the control group was statistically significant at 8 weeks after exposure. There was no significant difference in the methylation level of RASSF1A promoter region and the expression of mRNA among the groups. The methylation level of the promoter region of RASSF1A gene increased with the increase of exposure dose, and the difference between the high dose group and other groups was statistically significant (P 0.05). The expression of mRNA decreased with the increase of the exposure dose, and the difference between the control group and the low dose group was statistically significant compared with the high dose group (P 0.05). In addition, in the high dose group, there was a significant difference between the two groups. The methylation level of RASSF1A promoter at week 8 was lower than that at week 6, the difference was statistically significant (P 0.05), but the level of methylation in promoter region at week 12 was higher than that at week 6. The difference was statistically significant (P 0.05). The expression of mRNA decreased with the prolongation of exposure time, and the expression of mRNA at 8 and 12 weeks was significantly higher than that at 6 weeks (P 0.05). There was no significant difference in RASSF1A methylation level and mRNA expression under different exposure time (P0.05). Conclusion chronic exposure to vinyl chloride can increase the methylation level of RASSF1A gene promoter in rat hepatocytes. It may be involved in the epigenetic mechanism of carcinogenesis of vinyl chloride.
【作者单位】：山西医科大学公共卫生学院卫生毒理教研室;
【基金】：山西省基础研究计划项目(2013011059-1) 山西省回国留学人员科研资助项目(2016-056)
【分类号】：R114
【正文快照】： 氯乙烯(Vinyl chloride,VC)是工业生产聚氯乙烯(江苏溥博生物科技有限公司)。(PVC)的单体原料,2013年我国聚氯乙烯年产量达1动物天平(意欧仪器仪表有限公司),Line Gene529.54万吨,年均增长率达6.4%,成为世界第一大生9660荧光定量仪(杭州博日科技有限公司),Little产国和第一大

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