Slow cooling of human oocytes: ultrastructural injuries and apoptotic status.
Fertil Steril
; 91(4): 1023-34, 2009 Apr.
Article
em En
| MEDLINE
| ID: mdl-18367177
ABSTRACT
OBJECTIVE:
To identify the damages caused by slow cooling human metaphase II (MII) oocytes comparing the ultrastructure, inner mitochondrial membrane potential (DeltaPsim), and apoptotic status of fresh and cryopreserved oocytes.DESIGN:
Experimental study.SETTING:
University biology research unit and private IVF unit. PATIENT(S) Fresh and cryopreserved supernumerary MII oocytes donated from women undergoing IVF cycles. MAIN OUTCOME MEASURE(S) Ultrastructure was assessed by transmission electron microscopy (TEM), mitochondrial function by means of the fluorescent DeltaPsim reporter JC-1, and apoptotic status through fluorescent labeling with the pan-caspase inhibitor fluorescein isothiocyanate conjugate (FITC)-VAD FMK, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. RESULT(S) Compared to fresh oocytes, frozen/thawed (F/T) oocytes showed reduced cortical granule densities (F/T 3.35 +/- 1.94/10 microm vs. fresh 10.30 +/- 3.9/10 microm), swelling of smooth endoplasmic reticulum (F/T 0.084 +/- 0.03 microm(2) vs. fresh 0.040 +/- 0.02 microm(2)), decreased electron density of the mitochondrial matrix and damage to the mitochondrial membranes, low DeltaPsim of pericortical mitochondria, but no signs of apoptosis. CONCLUSION(S) Slow cooling is associated with cortical granule exocytosis, swelling of smooth endoplasmic reticulum vesicles, and mitochondrial damage, but does not induce early or late apoptotic events. The observed injuries might be responsible for the reduced developmental competence of cryopreserved oocytes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oócitos
/
Criopreservação
/
Apoptose
/
Retículo Endoplasmático Liso
/
Mitocôndrias
Tipo de estudo:
Evaluation_studies
/
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
Idioma:
En
Revista:
Fertil Steril
Ano de publicação:
2009
Tipo de documento:
Article