title: Females transplanted with ovaries subjected to hypoxic preconditioning show impair of ovarian function.
abstract: Cryopreservation of the ovarian tissue has shown promising results. However, there remain controversial issues such as the short half-life of grafts. In this aspect, there are some evidences that preconditioning the ovarian tissue before transplantation is beneficial.
  
  
  
  To determine the effect of hypoxic preconditioning in vitro on ovarian tissue prior to transplantation.
  
  
  
  Eighteen female adult Wistar rats, were sorted into three experimental groups. Ovaries were maintained in DMEM low glucose serum free at 37°C with 5% CO2, at atmospheric oxigen concentration (normoxia) or 1% O2 (hypoxia) for 16 hours. Oxigen concentration was determined by injection of nitrogen in the incubator. Animals submitted to ovarian transplantation immediately after oophorectomy were the Control Group (C). After this, the ovaries were implanted in the retroperitoneum with nonabsorbable suture and animals evaluated for thirty days after transplantation. Beginning on postoperative (PO) day 11, a daily collection of vaginal smear was carried out. Analyses comprised morphological, morphometric (counting ovarian follicles and corpora lutea) and immunohistochemistry for cleaved caspase-3 (apoptosis).
  
  
  
  In normoxia and control groups all animals recovered their estrous cycles, while in the hypoxia group, two animals did not ovulate but, among those which did, resumption took longer than in the other groups (p < 0.05). The number of ovarian follicles and corpora lutea decreased significantly in the hypoxia group when compared to the other two groups (p < 0.001) and apoptosis was increased in the few ovarian follicles which remained viable (p < 0.001).
  
  
  
  The hypoxic preconditioning in vitro was not beneficial to the graft and worsened their viability, compromising its functionality or delaying the return of this.
authors.affiliation: Gynecology Division, Department of Obstetrics and Gynecology, Laboratory of Structural and Molecular Gynecology (LIM-58), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil. lucianadamous@gmail.com.
authors.forename: Luciana Lamarão
authors.initials: LL
authors.lastname: Damous
authors.forename: Juliana Sanajotti
authors.initials: JS
authors.lastname: Nakamuta
authors.forename: José Maria
authors.initials: JM
authors.lastname: Soares
authors.forename: Gustavo Arantes Rosa
authors.initials: GA
authors.lastname: Maciel
authors.forename: Ricardo Dos Santos
authors.initials: Rdos S
authors.lastname: Simões
authors.forename: Edna Frasson de Souza
authors.initials: EF
authors.lastname: Montero
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Krieger
authors.forename: Edmund Chada
authors.initials: EC
authors.lastname: Baracat
mesh_terms: D000818:Animals; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D030762:Estrous Cycle; D005260:Female; D005298:Fertility; D006085:Graft Survival; D000860:Hypoxia / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D006080:Ovarian Follicle / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000637:transplantation*; D010052:Ovariectomy; D010053:Ovary / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000637:transplantation*; D010060:Ovulation; D010100:Oxygen / Q000378:metabolism*; D017208:Rats, Wistar; D020127:Recovery of Function; D013997:Time Factors; D046509:Tissue Culture Techniques; D014021:Tissue Preservation / Q000379:methods*; D014022:Tissue Survival
chemical_list: C505410:Casp3 protein, rat; D053148:Caspase 3; D010100:Oxygen