title: Cryoprotectants up-regulate expression of mouse oocyte AQP7, which facilitates water diffusion during cryopreservation.
abstract: OBJECTIVE
  To investigate the effects of cryoprotectants on the expression of AQP7 in oocytes.
  
  
  METHODS
  Experimental animal study.
  
  
  METHODS
  University-based research laboratory.
  
  
  METHODS
  Adult female C57BL/6J mice.
  
  
  METHODS
  In metaphase II (MII) oocytes obtained from adult female C57BL/6J mice and from donations by fertile women, the mouse oocytes were treated with human tubal fluid medium containing 8% ethylene glycol (EG), 9.5% dimethylsulfoxide (DMSO), and 0.5 M sucrose, respectively; 293T cells transfected with GFP-hAQP7 expression vector were treated with the same solutions.
  
  
  METHODS
  AQP7 expression in oocytes examined by reverse-transcriptase-nested polymerase chain reaction and immunofluorescence, changes in the volume of mouse oocytes treated with different solutions calculated to determine their permeability to water, and survival rates of vitrified oocytes.
  
  
  RESULTS
  AQP7 is expressed in human and mouse oocytes. Cryoprotectants, including EG, DMSO, and sucrose, up-regulated AQP7 expression in mouse oocytes and 293T cells transfected with GFP-hAQP7 expression vector. Compared with other cryoprotectants, DMSO stimulated higher expression of AQP7, and this was associated with faster cell volume recovery and lower survival rates of vitrified oocytes.
  
  
  CONCLUSIONS
  DMSO up-regulates AQP7 expression in mouse oocytes more than EG. This may facilitate water diffusion and reduce the time for oocytes to reach osmotic balance with the cryoprotectant solution during cryopreservation.
authors.affiliation: Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou, PR China.
authors.forename: Ya-Jing
authors.initials: YJ
authors.lastname: Tan
authors.forename: Yun
authors.initials: Y
authors.lastname: Xiong
authors.forename: Guo-Lian
authors.initials: GL
authors.lastname: Ding
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.forename: Ye
authors.initials: Y
authors.lastname: Meng
authors.forename: He-Feng
authors.initials: HF
authors.lastname: Huang
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Sheng
mesh_terms: D000328:Adult; D000818:Animals; D020346:Aquaporins / Q000235:genetics*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D015925:Cryopreservation / Q000379:methods; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D019855:Ethylene Glycol / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D013395:Sucrose / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects; D058989:Vitrification; D014867:Water / Q000378:metabolism; D055815:Young Adult
chemical_list: C114141:AQP7 protein, human; C491927:Aqp7 protein, mouse; D020346:Aquaporins; D003451:Cryoprotective Agents; D014867:Water; D049452:Green Fluorescent Proteins; D013395:Sucrose; D019855:Ethylene Glycol; D004121:Dimethyl Sulfoxide