title: Corticosteroids effect on caspase 3 expression in an in-vitro model of hypoxic brain cells.
abstract: OBJECTIVE
  Effects of corticosteroids (CS) in the brain of growth-restricted fetus remain largely unstudied. We investigated if dexamethasone (DXM) exposure contributes to neuronal injury in an in-vitro model of neuronal cells under hypoxic conditions (surrogate for fetal growth restriction).
  
  
  METHODS
  U87 glioblastoma cells exposed to hypoxic or normoxic conditions for 10 h were incubated in the absence or presence of DXM for 48 h. Apoptosis as possible indicator of neurotoxicity was determined using a caspase-3-specific activity assay and western blotting. Caspase-3 was calculated as percentage of mean caspase-3 cleavage. Each experiment was performed in triplicate (n = 48). Caspase 3 activity in cell culture media was also measured by ELISA.
  
  
  RESULTS
  Pro-caspase-3 (32 kDa) was expressed in culture, but activated 17 Kd caspase 3 was not expressed in cell lysate. There was no difference in ratio of caspase 3 activation when U87 cells were exposed to 10 v of hypoxia as compared to normoxia (0.46 ± 0.44 versus 0.37 ± 0.37). The pro-apoptotic effects of DXM were not increased by pre-exposure to hypoxia: (0.37 ± 0.37 versus 0.47 ± 0.40).
  
  
  CONCLUSIONS
  The addition of DXM to hypoxic U87 cells had no additive or synergistic effects on the activation of caspase 3. Therefore, we speculate that the administration of CS in the setting of fetal growth restriction would not lead to increased apoptosis with potential neuronal injury.
authors.affiliation: Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences and.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Carreno
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Alcorn
authors.forename: Alex C
authors.initials: AC
authors.lastname: Vidaeff
authors.forename: Karen D
authors.initials: KD
authors.lastname: Bishop
authors.forename: Sean C
authors.initials: SC
authors.lastname: Blackwell
authors.forename: Baha M
authors.initials: BM
authors.lastname: Sibai
mesh_terms: D000305:Adrenal Cortex Hormones / Q000494:pharmacology*; D053148:Caspase 3 / Q000378:metabolism*; D015687:Cell Hypoxia / Q000187:drug effects; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D002534:Hypoxia, Brain / Q000378:metabolism* / Q000473:pathology*; D008962:Models, Theoretical; D013997:Time Factors
chemical_list: D000305:Adrenal Cortex Hormones; D003907:Dexamethasone; D053148:Caspase 3