Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
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Target Concepts:
Gene/Protein
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Query: UMLS:C0038220 (
status epilepticus
)
7,272
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Status epilepticus
(SE) triggers abnormal expression of genes in the hippocampus, such as glutamate receptor subunit epsilon-2 (Grin2b/Nr2b) and brain-derived neurotrophic factor (Bdnf), that is thought to occur in temporal lobe epilepsy (TLE). We examined the underlying DNA methylation mechanisms and investigated whether these mechanisms contribute to the expression of these gene targets in the epileptic hippocampus. Experimental TLE was provoked by kainic acid-induced SE. Bisulfite sequencing analysis revealed increased Grin2b/Nr2b and decreased Bdnf DNA methylation levels that corresponded to decreased Grin2b/Nr2b and increased Bdnf mRNA and protein expression in the epileptic hippocampus. Blockade of
DNA methyltransferase
(
DNMT
) activity with zebularine decreased global DNA methylation levels and reduced Grin2b/Nr2b, but not Bdnf, DNA methylation levels. Interestingly, we found that
DNMT
blockade further decreased Grin2b/Nr2b mRNA expression whereas GRIN2B protein expression increased in the epileptic hippocampus, suggesting that a posttranscriptional mechanism may be involved. Using chromatin immunoprecipitation analysis we found that
DNMT
inhibition restored the decreases in AP2alpha transcription factor levels at the Grin2b/Nr2b promoter in the epileptic hippocampus.
DNMT
inhibition increased field excitatory postsynaptic potential in hippocampal slices isolated from epileptic rats. Electroencephalography (EEG) monitoring confirmed that
DNMT
inhibition did not significantly alter the disease course, but promoted the latency to seizure onset or SE. Thus, DNA methylation may be an early event triggered by SE that persists late into the epileptic hippocampus to contribute to gene expression changes in TLE.
...
PMID:Status epilepticus triggers early and late alterations in brain-derived neurotrophic factor and NMDA glutamate receptor Grin2b DNA methylation levels in the hippocampus. 2381 93
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.
...
PMID:RASgrf1, a Potential Methylatic Mediator of Anti-epileptogenesis? 3024 50