title: Peroxynitrite affects the cumulus cell defense of metaphase II mouse oocytes leading to disruption of the spindle structure in vitro.
abstract: OBJECTIVE
  To demonstrate the effects of peroxynitrite (ONOO(-)) on metaphase II mouse oocyte spindle structure and chromosomal alignment in presence and absence of cumulus cells.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  University-based research laboratory.
  
  
  METHODS
  Metaphase II mouse oocytes (n = 440).
  
  
  METHODS
  Metaphase II mouse oocytes, with and without cumulus cells, were exposed to ONOO(-), nitrite/nitrate, the final product of ONOO(-), and nontreated controls for 15 minutes. Oocytes were fixed and subjected to indirect immunofluorescence for detecting changes in the spindle and chromosomal alignment. Viability staining in exposed oocytes with and without cumulus cells was performed using the trypan blue dye exclusion method and compared with controls.
  
  
  METHODS
  Scoring the alterations in spindle and chromosomal alignment using immunofluorescent and confocal microscopy based on a previously validated system.
  
  
  RESULTS
  Most oocytes had poor scores for the spindle and chromosomal alignment with exposure to ONOO(-) in a dose-dependent manner compared with controls. Trypan blue staining revealed that most of the cumulus cells failed to survive treatment with ONOO(-) compared with controls.
  
  
  CONCLUSIONS
  ONOO(-) affects the viability of cumulus cells and the oocyte spindle structure in a dose-dependent manner. Collectively, these effects compromise oocyte quality, which may lead to female infertility.
authors.affiliation: Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Detroit, Michigan 48201, USA.
authors.forename: Jashoman
authors.initials: J
authors.lastname: Banerjee
authors.forename: Faten
authors.initials: F
authors.lastname: Shaeib
authors.forename: Dhiman
authors.initials: D
authors.lastname: Maitra
authors.forename: Ghassan M
authors.initials: GM
authors.lastname: Saed
authors.forename: Jing
authors.initials: J
authors.lastname: Dai
authors.forename: Michael P
authors.initials: MP
authors.lastname: Diamond
authors.forename: Husam M
authors.initials: HM
authors.lastname: Abu-Soud
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D054885:Cumulus Cells / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D004353:Drug Evaluation, Preclinical; D005260:Female; D008677:Metaphase / Q000187:drug effects* / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D030421:Peroxynitrous Acid / Q000494:pharmacology*; D008941:Spindle Apparatus / Q000187:drug effects*
chemical_list: D030421:Peroxynitrous Acid
keywords: Peroxynitrite; cumulus cells; oocyte quality; oxidative stress; reactive oxygen species