title: Insufficient histone-3 lysine-9 deacetylation in human oocytes matured in vitro is associated with aberrant meiosis.
abstract: OBJECTIVE
  To characterize histone acetylation during meiosis in human oocytes matured in vitro or in vivo.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  University reproductive medical center.
  
  
  METHODS
  Patients undergoing routine intracytoplasmic sperm injection (ICSI) cycles.
  
  
  METHODS
  Immature and mature oocytes were collected from patients undergoing intracytoplasmic sperm injection.
  
  
  METHODS
  Immunohistochemical assessment of the levels of acetylated lysine-9 of histone-3 (H3K9) and lysine-12 of histone-4 (H4K12) combined with spindle and chromosome configurations in in vitro- and in vivo-matured human oocytes. Transcript levels of histone deacetylases (HDACs) 1 and 2 were measured by single-cell quantitative polymerase chain reaction.
  
  
  RESULTS
  Acetylation of H3K9 and H4K12 decreased during human oocyte maturation. Residual H3K9 acetylation was found in 37.7% of oocytes matured in vitro, compared with 11.8% in oocytes matured in vivo. Abnormal metaphase spindle was more frequent in oocytes with residual histone acetylation than without (51.6% vs. 25.4%, respectively). Treatment with the HDAC inhibitor trichostatin A increased the incidence of an abnormal metaphase but had no adverse effect on maturation efficiency. Furthermore, expression of HDAC1 transcripts was significantly lower in oocytes matured in vitro versus in vivo.
  
  
  CONCLUSIONS
  Reduced HDAC1 expression and insufficient histone deacetylation are associated with metaphase defects in human oocytes matured in vitro.
authors.affiliation: Center of Reproductive Medicine, Department of Obstetrics and Gynecology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Jia
authors.initials: J
authors.lastname: Huang
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Chen-Hui
authors.initials: CH
authors.lastname: Ding
authors.forename: Jan
authors.initials: J
authors.lastname: Brosens
authors.forename: Can-Quan
authors.initials: CQ
authors.lastname: Zhou
authors.forename: Hui-Hui
authors.initials: HH
authors.lastname: Wang
authors.forename: Yan-Wen
authors.initials: YW
authors.lastname: Xu
mesh_terms: D000107:Acetylation; D000782:Aneuploidy; D003470:Culture Media / Q000494:pharmacology; D005260:Female; D056284:Histone Deacetylase 1 / Q000235:genetics / Q000378:metabolism*; D056464:Histone Deacetylase 2 / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D006801:Humans; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods*; D066298:In Vitro Techniques; D008239:Lysine / Q000378:metabolism; D008540:Meiosis / Q000502:physiology*; D054315:Oocyte Retrieval / Q000379:methods; D009865:Oocytes / Q000201:enzymology* / Q000473:pathology*; D010062:Ovulation Induction / Q000379:methods; D020554:Sperm Injections, Intracytoplasmic
chemical_list: D003470:Culture Media; D006657:Histones; C110550:HDAC1 protein, human; C533423:HDAC2 protein, human; D056284:Histone Deacetylase 1; D056464:Histone Deacetylase 2; D008239:Lysine