title: Dual action of H2O2 on placental hCG secretion: implications for oxidative stress in preeclampsia.
abstract: OBJECTIVE
  Our previously published findings showed that circulating levels of H(2)O(2) were increased and correlated with high levels of hCG in women with preeclampsia, suggesting that oxidative stress modulates placental hormone synthesis. The aim of this study was to investigate in vitro the effects of H(2)O(2) on placental secretion of hCG.
  
  
  METHODS
  In vitro trophoblasts were stimulated with increasing concentrations of H(2)O(2) and the de novo hCG secretion was assayed.
  
  
  RESULTS
  Stimulation with low concentrations of H(2)O(2) (1-50 microM) enhances cytotrophoblastic hCG secretion, whereas concentrations of H(2)O(2) >50 microM reduce hCG secretion in a dose-dependent manner.
  
  
  CONCLUSIONS
  Our findings emphasize that: (1) H(2)O(2) may have dual action on placental activity and acts not only as a cytotoxic mediator, but also as a signaling molecule able to induce hCG secretion; (2) hCG may be a protective antioxidant released by the placenta to counter low oxidative stress challenge.
authors.affiliation: Département d'Obstétrique-Gynécologie, Centre Hospitalier Universitaire de Sherbrooke. 3001, 12(e) Avenue Nord, Sherbrooke, Québec, Canada J1H 5N4. aziz.aris@usherbrooke.ca
authors.forename: Aziz
authors.initials: A
authors.lastname: Kharfi Aris
authors.forename: Samuel
authors.initials: S
authors.lastname: Leblanc
authors.forename: Annie
authors.initials: A
authors.lastname: Ouellet
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Moutquin
mesh_terms: D006063:Chorionic Gonadotropin / Q000378:metabolism*; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D011225:Pre-Eclampsia / Q000378:metabolism* / Q000503:physiopathology; D011247:Pregnancy; D014327:Trophoblasts / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D006063:Chorionic Gonadotropin; D006861:Hydrogen Peroxide