Cerebral ischemia/reperfusion injury impairs learning and memory in patients.Studies have shown that synaptic function is involved in the formation and development of memory,and that DNA methylation plays a key role i...Cerebral ischemia/reperfusion injury impairs learning and memory in patients.Studies have shown that synaptic function is involved in the formation and development of memory,and that DNA methylation plays a key role in the regulation of learning and memory.To investigate the role of DNA hypomethylation in cerebral ischemia/reperfusion injury,in this study,we established a rat model of cerebral ischemia/reperfusion injury by occlusion of the middle cerebral artery and then treated the rats with intraperitoneal 5-aza-2′-deoxycytidine,an inhibitor of DNA methylation.Our results showed that 5-aza-2′-deoxycytidine markedly improved the neurological function,and cognitive,social and spatial memory abilities,and dose-dependently increased the synaptic density and the expression of SYP and SHANK2 proteins in the hippocampus in a dose-dependent manner in rats with cerebral ischemia/reperfusion injury.The effects of 5-aza-2′-deoxycytidine were closely related to its reduction of genomic DNA methylation and DNA methylation at specific sites of the Syp and Shank2 genes in rats with cerebral ischemia/reperfusion injury.These findings suggest that inhibition of DNA methylation by 5-aza-2′-deoxycytidine promotes the recovery of learning and memory impairment in a rat model of cerebral ischemia/reperfusion injury.These results provide theoretical evidence for stroke treatment using epigenetic methods.展开更多
Trigeminal inflammatory pain is one of the most severe pain-related disorders in humans;however,the underlying mechanisms remain largely unknown.In this study,we investigated the possible contribution of interaction b...Trigeminal inflammatory pain is one of the most severe pain-related disorders in humans;however,the underlying mechanisms remain largely unknown.In this study,we investigated the possible contribution of interaction between ten-eleven translocation methylcytosine dioxygenase 1(TET1)and the voltage-gated K^(+)channel Kv7.2(encoded by Kcnq2)to orofacial inflammatory pain in mice.We found that complete Freund’s adjuvant(CFA)injection reduced the expression of Kcnq2/Kv7.2 in the trigeminal ganglion(TG)and induced orofacial inflammatory pain.The involvement of Kv7.2 in CFA-induced orofacial pain was further confirmed by Kv7.2 knockdown or overexpression.Moreover,TET1 knockdown in Tet1^(flox/flox)mice significantly reduced the expression of Kv7.2 and M currents in the TG and led to pain-like behaviors.Conversely,TET1 overexpression by lentivirus rescued the CFA-induced decreases of Kcnq2 and M currents and alleviated mechanical allodynia.Our data suggest that TET1 is implicated in CFA-induced trigeminal inflammatory pain by positively regulating Kv7.2 in TG neurons.展开更多
The cerebral cortex is a pivotal structure integral to advanced brain functions within the mammalian central nervous system.DNA methylation and hydroxymethylation play important roles in regulating cerebral cortex dev...The cerebral cortex is a pivotal structure integral to advanced brain functions within the mammalian central nervous system.DNA methylation and hydroxymethylation play important roles in regulating cerebral cortex development.However,it remains unclear whether abnormal cerebral cortex development,such as microcephaly,could rescale the epigenetic landscape,potentially contributing to dysregulated gene expression during brain development.In this study,we characterize and compare the DNA methylome/hydroxymethylome and transcriptome profiles of the cerebral cortex across several developmental stages in wild-type(WT)mice and Mcph1 knockout(Mcph1-del)mice with severe microcephaly.Intriguingly,we discover a global reduction of 5′-hydroxymethylcytosine(5hmC)level,primarily in TET1-binding regions,in Mcph1-del mice compared to WT mice during juvenile and adult stages.Notably,genes exhibiting diminished 5hmC levels and concurrently decreased expression are essential for neurodevelopment and brain functions.Additionally,genes displaying a delayed accumulation of 5hmC in Mcph1-del mice are significantly associated with the establishment and maintenance of the nervous system during the adult stage.These findings reveal that aberrant cerebral cortex development in the early stages profoundly alters the epigenetic regulation program,which provides unique insights into the molecular mechanisms underpinning diseases related to cerebral cortex development.展开更多
The methylcytosine dioxygenases TET proteins （TET1, TET2, and TET3） play important regulatory roles in neural function. In this study, we investigated the role of TET proteins in neuronal differentiation using Neuro...The methylcytosine dioxygenases TET proteins （TET1, TET2, and TET3） play important regulatory roles in neural function. In this study, we investigated the role of TET proteins in neuronal differentiation using Neuro2a cells as a model. We observed that knockdown of TET1, TET2 or TET3 promoted neuronal differentiation of Neuro2a cells, and their overexpression inhibited VPA （valproic acid）-induced neuronal differentiation, suggesting all three TET proteins negatively regulate neu- ronal differentiation of Neuro2a cells. Interestingly, the inducing activity of TET protein is independent of its enzymatic activity. Our previous studies have demon- strated that srGAP3 can negatively regulate neuronal differentiation of Neuro2a cells. Furthermore, we revealed that TET1 could positively regulate srGAP3 expression independent of its catalytic activity, and srGAP3 is required for TET-mediated neuronal differentiation of Neuro2a cells. The results presented here may facilitate better understanding of the role of TET proteins in neuronal differentiation, and provide a possible therapy target for neuroblastoma.展开更多
基金supported by the National Natural Science Foundation of China,No.82101567Doctoral Start-up Foundation of Liaoning Province,No.2021-BS-111345 Talent Project of Shengjing Hospital of China Medical University,No.M0673(all to XYF)。
文摘Cerebral ischemia/reperfusion injury impairs learning and memory in patients.Studies have shown that synaptic function is involved in the formation and development of memory,and that DNA methylation plays a key role in the regulation of learning and memory.To investigate the role of DNA hypomethylation in cerebral ischemia/reperfusion injury,in this study,we established a rat model of cerebral ischemia/reperfusion injury by occlusion of the middle cerebral artery and then treated the rats with intraperitoneal 5-aza-2′-deoxycytidine,an inhibitor of DNA methylation.Our results showed that 5-aza-2′-deoxycytidine markedly improved the neurological function,and cognitive,social and spatial memory abilities,and dose-dependently increased the synaptic density and the expression of SYP and SHANK2 proteins in the hippocampus in a dose-dependent manner in rats with cerebral ischemia/reperfusion injury.The effects of 5-aza-2′-deoxycytidine were closely related to its reduction of genomic DNA methylation and DNA methylation at specific sites of the Syp and Shank2 genes in rats with cerebral ischemia/reperfusion injury.These findings suggest that inhibition of DNA methylation by 5-aza-2′-deoxycytidine promotes the recovery of learning and memory impairment in a rat model of cerebral ischemia/reperfusion injury.These results provide theoretical evidence for stroke treatment using epigenetic methods.
基金supported by the National Natural Science Foundation of China(81771195 and 81971061)the Program for Innovative Research Team in Universities of Henan Province(22IRTSTHN028).
文摘Trigeminal inflammatory pain is one of the most severe pain-related disorders in humans;however,the underlying mechanisms remain largely unknown.In this study,we investigated the possible contribution of interaction between ten-eleven translocation methylcytosine dioxygenase 1(TET1)and the voltage-gated K^(+)channel Kv7.2(encoded by Kcnq2)to orofacial inflammatory pain in mice.We found that complete Freund’s adjuvant(CFA)injection reduced the expression of Kcnq2/Kv7.2 in the trigeminal ganglion(TG)and induced orofacial inflammatory pain.The involvement of Kv7.2 in CFA-induced orofacial pain was further confirmed by Kv7.2 knockdown or overexpression.Moreover,TET1 knockdown in Tet1^(flox/flox)mice significantly reduced the expression of Kv7.2 and M currents in the TG and led to pain-like behaviors.Conversely,TET1 overexpression by lentivirus rescued the CFA-induced decreases of Kcnq2 and M currents and alleviated mechanical allodynia.Our data suggest that TET1 is implicated in CFA-induced trigeminal inflammatory pain by positively regulating Kv7.2 in TG neurons.
基金supported by the National Natural Science Foundation of China(81872299 to X.L.and 3217070538 to W.Z.Z.)Shenzhen Science and Technology Program(JCYJ20190807160011600 and JCYJ20210324124808023 to X.L.+1 种基金JCYJ20200109142446804,JCYJ20220530145807018,ZDSYS20220606100803007,and JCYJ20190807154407467 to W.Z.Z.)Guangdong Provincial Key Laboratory of Digestive Cancer Research(2021B1212040006 to X.L.),and China Postdoctoral Science Foundation(2020M683073 to Y.Z.S.).
文摘The cerebral cortex is a pivotal structure integral to advanced brain functions within the mammalian central nervous system.DNA methylation and hydroxymethylation play important roles in regulating cerebral cortex development.However,it remains unclear whether abnormal cerebral cortex development,such as microcephaly,could rescale the epigenetic landscape,potentially contributing to dysregulated gene expression during brain development.In this study,we characterize and compare the DNA methylome/hydroxymethylome and transcriptome profiles of the cerebral cortex across several developmental stages in wild-type(WT)mice and Mcph1 knockout(Mcph1-del)mice with severe microcephaly.Intriguingly,we discover a global reduction of 5′-hydroxymethylcytosine(5hmC)level,primarily in TET1-binding regions,in Mcph1-del mice compared to WT mice during juvenile and adult stages.Notably,genes exhibiting diminished 5hmC levels and concurrently decreased expression are essential for neurodevelopment and brain functions.Additionally,genes displaying a delayed accumulation of 5hmC in Mcph1-del mice are significantly associated with the establishment and maintenance of the nervous system during the adult stage.These findings reveal that aberrant cerebral cortex development in the early stages profoundly alters the epigenetic regulation program,which provides unique insights into the molecular mechanisms underpinning diseases related to cerebral cortex development.
文摘The methylcytosine dioxygenases TET proteins （TET1, TET2, and TET3） play important regulatory roles in neural function. In this study, we investigated the role of TET proteins in neuronal differentiation using Neuro2a cells as a model. We observed that knockdown of TET1, TET2 or TET3 promoted neuronal differentiation of Neuro2a cells, and their overexpression inhibited VPA （valproic acid）-induced neuronal differentiation, suggesting all three TET proteins negatively regulate neu- ronal differentiation of Neuro2a cells. Interestingly, the inducing activity of TET protein is independent of its enzymatic activity. Our previous studies have demon- strated that srGAP3 can negatively regulate neuronal differentiation of Neuro2a cells. Furthermore, we revealed that TET1 could positively regulate srGAP3 expression independent of its catalytic activity, and srGAP3 is required for TET-mediated neuronal differentiation of Neuro2a cells. The results presented here may facilitate better understanding of the role of TET proteins in neuronal differentiation, and provide a possible therapy target for neuroblastoma.
