The feasibility to accurately select viable embryos would be valuable for improving pregnancy rates and avoiding futile transfer attempts. The aim of our study was to assess if in vitro-produced embryo quality could be determined by the timing of blastocoelic cavity re-expansion after vitrification, warming, and in vitro culture using sheep as a model. Blastocysts were produced in vitro, vitrified/warmed, and cultured in TCM-199 plus 10% FCS for 72 hr. Embryos were divided into two groups: re-expanded within 8 hr (A) and from 8 to 16 hr (B) of IVC after warming. Fast re-expanded blastocysts showed higher in vitro hatching rates and total cell number calculated on the hatched blastocysts compared with slow re-expanded ones (P < 0.01). Peroxide status evaluation (P < 0.01) and TUNEL test (P < 0.05) revealed a higher number of positive cells in group B compared with group A. The quantitative analysis of protein synthesis revealed a higher synthesis in fast compared with slow re-expanded embryos (P < 0.05). Quantitative RT-PCR showed that 90-kDa Heat Shock Protein β was more expressed in group A than in group B (P < 0.05), while the quantity of P34cdc2, Cyclin b, Aquaporin 3, Na/K ATPase, and Actin did not differ between the two groups. Pregnancy rates after transfer to synchronized recipients were higher in fast compared to slow re-expanded blastocysts (P < 0.05). Our results evidenced that timing of blastocoelic cavity re-expansion after vitrification/warming and in vitro culture can be considered as a reliable index of in vitro produced embryo quality and developmental potential.
A new selection criterion to assess good quality ovine blastocysts after vitrification and to predict their transfer into recipients / G.G. Leoni, F. Berlinguer, S. Succu, D. Bebbere, F. Mossa, M. Madeddu, S. Ledda, L. Bogliolo, S. Naitana. - In: MOLECULAR REPRODUCTION AND DEVELOPMENT. - ISSN 1040-452X. - 75:2(2008), pp. 373-382. [10.1002/mrd.20754]
|Titolo:||A new selection criterion to assess good quality ovine blastocysts after vitrification and to predict their transfer into recipients|
|Parole Chiave:||Developmental potential; DNA fragmentation; Gene expression; Protein synthesis; Re-expansion time; Animals; Blastocyst; Embryo Implantation; Female; Fertilization in Vitro; In Situ Nick-End Labeling; Oocytes; RNA, Messenger; Reverse Transcriptase Polymerase Chain Reaction; Sheep|
|Settore Scientifico Disciplinare:||Settore VET/02 - Fisiologia Veterinaria|
|Data di pubblicazione:||2008|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/mrd.20754|
|Appare nelle tipologie:||01 - Articolo su periodico|