香烟烟雾暴露对幼年大鼠海马DNA甲基化的影响

目的:探讨香烟烟雾暴露对新生大鼠海马细胞DNA甲基化的水平的影响。方法:18只的SD幼年大鼠随机分为对照组(control)、香烟烟雾暴露组(cigarette smoke),香烟烟雾暴露组大鼠进行香烟烟雾暴露30 d,利用商品化试剂盒检测各组大鼠海马组织5'甲基胞嘧啶(5-mC)的变化,real time RT-PCR检测各组大鼠海马DNA甲基转移酶1(DNMT1)、DNA甲基转移酶3a(DNMT3a)及DNA甲基转移酶3b(DNMT3b)mRNA表达水平,Western Blot检测各组大鼠海马DNMT1、DNMT3a及DNMT3b蛋白水平表达。结果:与对照组相比,香烟烟雾暴露可导致大鼠海马5-mC水平增加,海马DNMT1 mRNA和蛋白表达增加。结论:幼年大鼠香烟烟雾暴露会上调海马组织DNMT1的表达,进而增加DNA甲基化水平。

The effects of cigarette smoke exposure on DNA methylation of hippocampus in young rats

Objective:To investigate the effects of cigarette smoke exposure on the level of DNA methylation in young rat hippocampal cells.Methods:Eighteen young Sprague Dawley rats were randomly divided into control group and cigarette smoke exposure group.The rats of cigarette smoke exposure group were continuously exposed to cigarette smoke for 30 days.The levels of hippocampal 5'-methyl cytosine(5-mC)were tested using commercial kits in hippocampus of rats.The expression of DNA methyltransferase1(DNMT1),DNMT3a,and DNMT3b mRNA was tested by real time RT-PCR in hippocampus of rats.The expression of DNMT1,DNMT3a,and DNMT3b protein was tested by Western Blot in hippocampus of rats.Results:Compared with the control group,cigarette smoke exposure increased the level of 5-mC,DNMT1 mRNA,and DNMT1 protein in the hippocampus of rats.Conclusion:Cigarette smoke exposure can promote DNA methylation and upregulate the expression of DNMT1 in hippocampus of young rats.