title: [Protective effects of IGF-1 on cortical nerve cells of neonatal rats under oxidative stress].
abstract: OBJECTIVE
  To investigate the protective effects of insulin-like growth factor-1 (IGF-1) on the nerve cells of neonatal rats under oxidative stress.
  
  
  METHODS
  Primary cortical neurons, oligodendrocytes, and astrocytes from newborn rats were cultured. An oxidative stress model was established with different concentrations of H2O2 (0-60 μmol/L); the degree of damage of nerve cells was evaluated by lactate dehydrogenase assay, and the viability of nerve cells was tested by MTT assay. An oxidative stress model was established with different concentration of H2O2 (0-80 μmol/L). Expression of Akt/p-Akt (Ser473) in neurons was measured by Western blot before and after IGF-1 (25 ng/mL) administration.
  
  
  RESULTS
  Compared with those not treated with H2O2, the cortical neurons, oligodendrocytes, and astrocytes treated with different concentrations of H2O2 for 24 hours showed increased damage and decreased cell viability; compared with oligodendrocytes and astrocytes, neurons showed significantly more changes (P<0.01). Compared with those not treated with H2O2, the cortical neurons treated with different concentrations of H2O2 for 5 minutes showed a significant decrease in p-Akt (Ser473) level (P<0.01), which was dependent on the concentration of H2O2. For the neurons treated with low-concentration H2O2, the addition of IGF-1 could reverse the inhibition of Akt phosphorylation, eliminating the difference in p-Akt level compared with the neurons not treated with H2O2, (P>0.05); however, it had no significant effect on the inhibition of Akt phosphorylation by high-concentration H2O2, and the treated neurons still had a lower p-Akt level than untreated neurons (P<0.01 for all). For the cortical neurons that had been treated with different concentration of H2O2 for 1 hour, the addition of IGF-1 (25 ng/mL) could eliminate thedifference in p-Akt level between the treated neurons and untreated neurons (P>0.05).
  
  
  CONCLUSIONS
  Cortical neurons are more sensitive to oxidative stress induced by H2O2 than other nerve cells. IGF-1 has protective effects on cortical nerve cells under oxidative stress.
authors.affiliation: Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. lwchang@tjh.tjmu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Li
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Chen
authors.forename: Zhi-Hui
authors.initials: ZH
authors.lastname: Rong
authors.forename: Li-Wen
authors.initials: LW
authors.lastname: Chang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018384:Oxidative Stress; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D007334:Insulin-Like Growth Factor I; D006861:Hydrogen Peroxide; D051057:Proto-Oncogene Proteins c-akt