title: Chronic unpredictable stress decreases expression of brain-derived neurotrophic factor (BDNF) in mouse ovaries: relationship to oocytes developmental potential.
abstract: BACKGROUND
  Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary.
  
  
  METHODS
  Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA) axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated.
  
  
  RESULTS
  Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment.
  
  
  CONCLUSIONS
  BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.
authors.affiliation: Centre for Reproductive Medicine, Anhui Provincial Hospital Affiliated to Anhui Medical University, Hefei, China. wlm@ustc.edu.cn
authors.forename: Li-Min
authors.initials: LM
authors.lastname: Wu
authors.forename: Mei-Hong
authors.initials: MH
authors.lastname: Hu
authors.forename: Xian-Hong
authors.initials: XH
authors.lastname: Tong
authors.forename: Hui
authors.initials: H
authors.lastname: Han
authors.forename: Ni
authors.initials: N
authors.lastname: Shen
authors.forename: Ren-Tao
authors.initials: RT
authors.lastname: Jin
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Gui-Xiang
authors.initials: GX
authors.lastname: Zhou
authors.forename: Guo-Ping
authors.initials: GP
authors.lastname: He
authors.forename: Yu-Sheng
authors.initials: YS
authors.lastname: Liu
mesh_terms: D000818:Animals; D015153:Blotting, Western; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism* / Q000494:pharmacology*; D005260:Female; D007150:Immunohistochemistry; D051379:Mice; D009866:Oogenesis / Q000187:drug effects; D010053:Ovary / Q000187:drug effects* / Q000378:metabolism*; D011897:Random Allocation; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D019208:Brain-Derived Neurotrophic Factor