RASgrf1, aPotential Methylatic Mediator ofAnti-epileptogenesis?
RASgrf1, aPotential Methylatic Mediator ofAnti-epileptogenesis?
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RASgrf1，抗癫痫发生的潜在甲基化介质？
DOI：
10.1007/s11064-018-2621-9
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发表时间：
2018
影响因子：
4.4
通讯作者：
Xiao Zheng
中科院分区：
文献类型：
--
作者：
Bao Yi;Chen Xiaoni;Wang Liang;Zhou Jixiu;Fu Xinwei;Wang Xuefeng;Xiao Zheng
癫痫持续状态(SE)引起的癫痫发生是一个慢性过程，干预这一过程可以预防慢性癫痫的发生。DNA甲基化可能与癫痫的发生有关。RASgrf1在启动子上有一个差异甲基化区域，可以沉默基因的表达。我们已经观察到癫痫患者RASgrf1基因的表达下调，并证明在海人酸致癫痫小鼠(KA小鼠)的潜伏期，RASgrf1的甲基化水平达到最高水平，相应地RASgrf1的表达也发生了变化。本研究用脱氧核糖核酸甲基转移酶抑制剂N-邻苯二甲酰-L-色氨酸(RG108)对KA小鼠进行潜伏期应用，并在慢性期观察其行为、脑电及病理改变。用聚合酶链式反应、免疫印迹和亚硫酸氢盐测序聚合酶链式反应检测RASgrf1的甲基化和表达。结果表明，RG108组小鼠的自发性惊厥(SRS)发生率明显低于生理盐水组(NS组)。亚组分析显示，与对照组相比，RG108-SRS亚组和NS-SRS亚组RASgrf1基因高甲基化和低表达，而RG108-NSRS(无SRS)亚组和NS-NSRS亚组RASgrf1表达无明显差异。RG108-SRS亚组与NS-SRS亚组间差异无统计学意义。同时观察到RG108-SRS和NS-SRS亚组的海马神经元丢失。因此，我们证明RG108可以改变KA诱导的SE后癫痫的进展，预防慢性癫痫的发生。同时，KA诱导的SE后RASgrf1的甲基化可被逆转，相应的RASgrf1的表达也发生了相应的变化。此外，我们推测RASgrf1可能是癫痫发生和慢性癫痫发病过程中潜在的表观遗传介质。
Epileptogenesis, induced by status epilepticus (SE), is a chronic process, and intervention in this progress may prevent chronic epilepsy. It has been proposed that DNA methylation might be related with epileptogenesis. RASgrf1 has a differentially methylated region at the promoter which can silence gene expression. We have previously observed the down-regulation of RASgrf1 in epilepsy patients and proved that hypermethylation of RASgrf1 reaches maximal level at the latent period in mice after kainate-induced SE (KA mice), with corresponding alteration of RASgrf1 expression. In the present study,N-phthalyl-L-tryptophan (RG108), a DNA methyltransferase inhibitor, was applied in KA mice at latent phase and the behavior, electroencephalogram and pathological changes were observed in chronic phase. Methylation and expression of RASgrf1 were determined by polymerase chain reaction (PCR), western blotting, and bisulfite sequencing PCR. The results showed that the incidence of spontaneous recurrent seizures (SRS) was significantly lower in the RG108 group than the normal saline (NS) group. Subgroup analysis showed significant hypermethylation and lower expression of RASgrf1 in the RG108–SRS subgroup and the NS–SRS subgroup but not in the RG108–NSRS (no SRS) subgroup and the NS–NSRS subgroup compared with the control group. No significant difference was found between the RG108–SRS and NS–SRS subgroups. Meanwhile, hippocampal neuronal loss was observed in RG108–SRS and NS–SRS subgroups. We thus demonstrated that RG108 could modify the progression of epileptogenesis after KA induced SE and prevent chronic epilepsy. Meanwhile, hypermethylation of RASgrf1 after KA induced SE could be reversed with corresponding changes of RASgrf1 expression. Additionally, we speculated that RASgrf1 might be a potential epigenetic mediator in epileptogenesis and chronic epilepsy.