title: Supplementation with low concentrations of melatonin improves nuclear maturation of human oocytes in vitro.
abstract: OBJECTIVE
  Studies in bovine and porcine have indicated that melatonin (MT) could induce meiotic maturation of immature oocytes in vitro. The object of the current study was to investigate if MT could ameliorate human oocytes maturation during rescue in vitro maturation (IVM).
  
  
  METHODS
  Two hundred seventy eight germinal vesicle (GV) oocytes and 451 (MI) metaphase I oocytes were vitrified, thawed and then matured in vitro. All the oocytes were randomly allocated into six groups in which the oocytes were cultured in medium supplemented with different concentrations of MT (0, 10(-2), 1, 10(2), 10(4), 10(6) nM) and nuclear maturation was evaluated at 6 h, 12 h, 18 h, 24 h and 48 h of culture.
  
  
  RESULTS
  The optimal MT concentration for both GV and MI oocytes was 1 nM. At 24 h of culture, nuclear maturation rate of MI oocytes cultured in 1 nM MT medium was significantly higher than other groups (P < 0.05); Nuclear maturation rate of GV oocytes cultured in 1 nM MT medium was also significantly higher than the control group (P < 0.05). On the other hand, decreased nuclear maturation rate was observed in the high MT concentration group (10(6) nM).
  
  
  CONCLUSIONS
  The current study demonstrated that low concentration of exogenous MT could ameliorate nuclear maturation of human oocyte during rescue IVM, while high concentration of MT presented negative effects.
authors.affiliation: Reproductive Medicine Center, the People's Hospital of Zhengzhou University; Henan Provincial People's Hospital, Henan, China.
authors.forename: Duo
authors.initials: D
authors.lastname: Wei
authors.forename: Cuilian
authors.initials: C
authors.lastname: Zhang
authors.forename: Culian
authors.initials: C
authors.lastname: Zhang
authors.forename: Juanke
authors.initials: J
authors.lastname: Xie
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Song
authors.forename: Baoli
authors.initials: B
authors.lastname: Yin
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Hu
authors.forename: Haoying
authors.initials: H
authors.lastname: Hao
authors.forename: Jiaxuan
authors.initials: J
authors.lastname: Geng
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
mesh_terms: D000328:Adult; D018929:Cell Culture Techniques; D002467:Cell Nucleus / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008550:Melatonin / Q000494:pharmacology*; D054315:Oocyte Retrieval; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D010062:Ovulation Induction; D020554:Sperm Injections, Intracytoplasmic; D055815:Young Adult
chemical_list: D008550:Melatonin