title: [Hydrogen peroxide-induced changes of PPARγ in primary cultured cortical neurons].
abstract: OBJECTIVE
  To investigate whether H₂O₂treatment negatively regulates PPARγ in primary cortical neurons by increasing PPARγ phosphorylation.
  
  
  METHODS
  Primary cultured cortical neurons were treated with H₂O₂(250, 500, and 750 µmol/L) for 2 h. 30 min before the H₂O₂(500 µmol/L), the specific inhibitor of ERK1/2 activation, U0126, was added to the culture. Morphological observation, MTT assay and the trypan blue exclusion method were used to detect cell damage. Western blot was carried out to evaluate the expressions of p-PPARγ (phospho-PPARγ) and total PPARγ, as well as to investigate the nuclear translocation of PPARγ (PPARγ activity).
  
  
  RESULTS
  (1) Compared with the control group, cell survival rates were decreased by H₂O₂at concentrations of 250, 500, and 750 µmol/L (74.8% ± 5.2%, 53.6% ± 6.7% and 26.5% ± 5.8%, respectively, P < 0.05), while cell death rate were increased (ctrl group 6.6% ± 1.0%, H₂O₂-injured groups: 23.1% ± 2.8%, 48.2% ± 4.1% and 75.9% ± 4.4% respectively, P < 0.05). (2) Compared with the control group, the expression of total PPARγ failed to show significant change in H₂O₂-injured group, whereas the expression of p-PPARγ increased. Neurons injured by H₂O₂(500 µmol/L) also showed a reduction of PPARγ nuclear translocation (an increase in cytosol PPARγ and a simultaneous decrease in nuclear PPARγ). (3) Compared with H₂O₂-injured group, inhibition of ERK1/2 activation decreased p-PPARγ expression, and increased PPARγ nuclear translocation, as well as improved cell survival rate (53.6% ± 6.7% vs 70.8% ± 1.3%, P < 0.05) and decreased cell death rate (48.2% ± 4.1% vs 29.8%±3.4%, P < 0.05).
  
  
  CONCLUSIONS
  Phosphorylation of PPARγ may be involved in cell death induced by hydrogen peroxide in primary cultured cortical neurons.
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liang
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Department of Neurology, Tianjin Medical University General Hospital, Tianjin 300052, China; Email: sunli_2000@hotmail.com.
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D001921:Brain; D002470:Cell Survival; D006861:Hydrogen Peroxide; D048052:Mitogen-Activated Protein Kinase 3; D009474:Neurons; D047495:PPAR gamma; D010766:Phosphorylation
chemical_list: D047495:PPAR gamma; D006861:Hydrogen Peroxide; D048052:Mitogen-Activated Protein Kinase 3