title: Consequences of metaphase II oocyte cryopreservation on mRNA content.
abstract: BACKGROUND
  We studied the consequences of freezing/thawing processes on mRNA contents in MII oocytes after slow-freezing/rapid thawing (SF/RT) and vitrification/warming (V/W) protocols, and compared the results to fresh MII oocytes. We quantified the nuclear transcript mRNA responsible for the translation of proteins belonging either to trans-regulatory protein family or to functional structural proteins such as proteins involved in DNA structural organization (NAP1L1, TOP1, H1F0H1), chromosomal structure maintenance (SMC, SCC3, RAD21, SMC1A, SMC1B, STAG3, REC8), mitochondrial energetic pathways (ATP5GJ, SDHC), cell cycle regulation and processes (CLTA, MAPK6, CKS2) and staminal cell potency-development competence stage (DPPA3, OCT4, FOXJ2).
  
  
  METHODS
  Surplus MII oocytes were donated from patients in IVF cycles and divided in three groups of 15 oocytes. Group 1 was comprised of non-cryopreserved oocytes and Groups 2 and 3 underwent SF/RT and V/W procedures, respectively.
  
  
  RESULTS
  There was an overall decrease of mRNA extracted from cryopreserved oocytes compared to control group. Only 39.4% of mRNA content were preserved after SF/RT while 63.3% of mRNA content were maintained after V/W.
  
  
  CONCLUSIONS
  Oocyte cryopreservation is associated with molecular injury associated with the decrease of stored mRNA. However the V/W protocol is more conservative than SF/RT resulting in a level of mRNA sufficient to maintain biologic functions in the subsequent fertilized oocyte.
authors.affiliation: Unità di Medicina della Riproduzione--Fondazione Hera, Via Barriera del Bosco n. 51/53, Sant'Agata Li Battiali (CT), Italy. s.chamayou@yahoo.fr
authors.forename: S
authors.initials: S
authors.lastname: Chamayou
authors.forename: G
authors.initials: G
authors.lastname: Bonaventura
authors.forename: C
authors.initials: C
authors.lastname: Alecci
authors.forename: D
authors.initials: D
authors.lastname: Tibullo
authors.forename: F
authors.initials: F
authors.lastname: Di Raimondo
authors.forename: A
authors.initials: A
authors.lastname: Guglielmino
authors.forename: M L
authors.initials: ML
authors.lastname: Barcellona
mesh_terms: D015925:Cryopreservation / Q000379:methods*; D005260:Female; D006358:Hot Temperature; D006801:Humans; D008677:Metaphase / Q000502:physiology*; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D012333:RNA, Messenger / Q000302:isolation & purification* / Q000378:metabolism*; D013048:Specimen Handling; D058989:Vitrification
chemical_list: D012333:RNA, Messenger