title: [The association of DNA methylation and DNA oxidation induced by H2O2].
abstract: OBJECTIVE
  To study the potential association of DNA oxidation and DNA methylation, in vitro cultured cells were exposed to different doses of H2O2, 8-oxo-dG formation, cell DNA 5-mC contents were analyzed to explore the time- dose-response relationship of DNA oxidation and DNA methylation.
  
  
  METHODS
  A549 cells were exposed to different doses of H2O2, 8-oxo-dG formation and cell genomic DNA 5-mC contents were analyzed by a high-performance liquid chromatography system and high performance capillary electrophoresis (HPCE), respectively.
  
  
  RESULTS
  H2O2 induced the formation of 8-oxo-dG and 5-mC in different characteristics, it need at least 10 days for significant changes in the level of DNA methylation, whereas under the same conditions, changes in the level of DNA oxidation cast only 12 hours. H2O2 induced decreased levels of DNA methylation in A549 cells in a dose-dependent manner. In a certain range of time and dose, it showed a negative correlation between DNA oxidation and DNA methylation.
  
  
  CONCLUSIONS
  The study suggests that oxidative DNA could lead to reduced levels of DNA methylation, DNA oxidation may affect the regulation of cellular methylation mechanisms, in the course of chemical mutagenesis, DNA oxidation may be an earlier important molecule event than DNA methylation.
authors.affiliation: Shenzhen Center for Diseases Control and Prevention, Shenzhen 518055, China.
authors.forename: Yuebin
authors.initials: Y
authors.lastname: Ke
authors.affiliation: Shenzhen Center for Diseases Control and Prevention, Shenzhen 518055, China.
authors.forename: Xinyun
authors.initials: X
authors.lastname: Xu
authors.affiliation: Shenzhen Center for Diseases Control and Prevention, Shenzhen 518055, China.
authors.forename: Shujiang
authors.initials: S
authors.lastname: Mei
authors.affiliation: Shenzhen Center for Diseases Control and Prevention, Shenzhen 518055, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Xie
authors.affiliation: Shenzhen Center for Diseases Control and Prevention, Shenzhen 518055, China.
authors.forename: Gonghua
authors.initials: G
authors.lastname: Tao
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D002460:Cell Line; D004247:DNA / Q000737:chemistry; D004249:DNA Damage; D019175:DNA Methylation; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000737:chemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity*; D018384:Oxidative Stress
chemical_list: D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; D006861:Hydrogen Peroxide; D003849:Deoxyguanosine