title: [Effect of HIF-1alpha on sex hormone levels and germ cell apoptosis of mice].
abstract: OBJECTIVE
  To study the effect of hypoxia on hypothalamus-adenohypophysis-testis axis hormone levels, germ cell apoptosis and hypoxia-inducible factor-1alpha (HIF-1alpha) expression in testis of adolescent mice, and explore HIF-1alpha regulation on the reproductive function of male mice.
  
  
  METHODS
  Eighty SPF grade adolescent C57BL/6 mice were randomly divided into normoxia group, hypoxia 3, 7, 14 and 28 d groups. The level of serum testosterone (T), free testosterone (FT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was analyzed by ELISA. Detected the sperm count, motility rate and abnormal sperm rate of epididymal sperm suspension. The apoptosis cells in testis were determined using TUNEL method. The expression of HIF-1alpha was analyzed using Western blot.
  
  
  RESULTS
  Compared with corresponding normoxia group, serum T, FT, FSH and LH concentrations in hypoxia 3 d group were significantly higher (P < 0.05); T and LH concentrations in hypoxia 14 d group were significantly lower (P < 0.05). Sperm count and motility rate in hypoxia 7 and 14 d groups significantly declined (P < 0.05); abnormal sperm rate in all hypoxia groups significantly increased (P < 0.05). The apoptosis index (AI) of germ cells in hypoxia 7, 14 and 28 d groups significantly increased (P < 0.05), and the levels of HIF-1alpha protein expression were significantly higher (P < 0.05).
  
  
  CONCLUSIONS
  HIF-1alpha protein highly expressed in mice testis could induce germ cell apoptosis increased in chronic hypoxia environment.
authors.affiliation: Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China.
authors.forename: Xiang-Mei
authors.initials: XM
authors.lastname: Chen
authors.forename: Yan-Lei
authors.initials: YL
authors.lastname: Xiong
authors.forename: Hui
authors.initials: H
authors.lastname: Gong
authors.forename: Cheng-Li
authors.initials: CL
authors.lastname: Xu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D005854:Germ Cells / Q000187:drug effects* / Q000378:metabolism; D012739:Gonadal Steroid Hormones / Q000378:metabolism*; D000860:Hypoxia; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013737:Testis / Q000166:cytology / Q000378:metabolism*
chemical_list: D012739:Gonadal Steroid Hormones; C497443:Hif1a protein, mouse; D051795:Hypoxia-Inducible Factor 1, alpha Subunit