title: [Effects on survival of shRNA mediated APE/Ref1 gene silencing in rat spiral ganglion cells in oxidative stress].
abstract: OBJECTIVE
  To investigate the effects of reducing APE/Ref1 expression in the cultures of rat spiral ganglion cells with oxidative damage induced by H(2)O(2).
  
  
  METHODS
  Primary cultured rat spiral ganglion cells were infected with small interfering RNA to APE/Ref1 (Ape1siRNA) for 72 h, followed by treating with H(2)O(2) (0, 10, 25, 50, 100 and 300 µmol/L) for 1 h , and then cultured in normal medium for 24 h. Western blot were used to detect the level of APE/Ref1 protein and phosphorylation of histone protein H2AX in the infected cells. The caspase3 activation was tested by spectrophotometric method . The cell viability was determined by MTT and the apoptosis of spiral ganglion cells was determined by terminal-deoxynucleotidyl transferase mediated nick and labeling (TUNEL).
  
  
  RESULTS
  Western blot showed that infection with Ape1siRNA resulted in APE/Ref1 reduced expression in the spiral ganglion cells. Exposing spiral ganglion cultures with reduced expression of APE/Ref1 to H(2)O(2) (50, 100, 300 µmol/L) for 1 h resulted in increasing in the phosphorylation of histone protein H2AX. The reduction in APE/Ref1 significantly reduced cell viability in cultures 24 h after 1 h expression to 50-300 µmol/L H(2)O(2). The apoptosis of cells and caspase 3 activity was detected significantly improved.
  
  
  CONCLUSIONS
  The induced of APE/Ref1 results in significantly decrease in spiral ganglion cells viability in oxidative stress. The repairing function of APE/Ref1 is necessary for optimal levels of neuronal rat spiral ganglion cells survival.
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Xinan Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Zhendong
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Xinan Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhong
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Xinan Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Taijun
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Xinan Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Zhaolan
authors.initials: Z
authors.lastname: Xiang
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Xinan Hospital, Third Military Medical University, Chongqing 400038, China. Email: yingsc@public.cta.cq.cn.
authors.forename: Xueyuan
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000235:genetics*; D020868:Gene Silencing; D006861:Hydrogen Peroxide; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D034741:RNA, Small Interfering; D051381:Rats; D017207:Rats, Sprague-Dawley; D013136:Spiral Ganglion / Q000166:cytology / Q000378:metabolism*
chemical_list: D034741:RNA, Small Interfering; D006861:Hydrogen Peroxide; C470319:Apex1 protein, rat; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase