Aging-related changes in in vitro-matured bovine oocytes: oxidative stress, mitochondrial activity and ATP content after nuclear maturation.
J Reprod Dev
; 60(2): 136-42, 2014 Apr 24.
Article
en En
| MEDLINE
| ID: mdl-24492658
ABSTRACT
The objective of this research was to clarify the aging-related changes in in vitro-matured bovine oocytes. Firstly, we examined the fertilization and embryonic development of bovine oocytes after 22 and 30-34 h of in vitro maturation (IVM). The oocytes after 30-34 h of IVM (penetrated by sperm at around 40 h after starting IVM) showed a lower developmental rate to blastocysts (P<0.01), although normal fertilization rates were similar regardless of IVM duration. In the next experiment, reactive oxygen species (ROS), mitochondrial activity and ATP content in oocytes after 20, 30 and 40 h of IVM were examined. The lowest level of ROS was found in the group subjected to 30 h of IVM. The mitochondrial activity and ATP content in the group subjected to 40 h of IVM were higher than in the group subjected to 20 h of IVM (P<0.01), and those in the group subjected to 30 h of IVM showed intermediate values. Thereafter, the mitochondrial activities at 3 days after in vitro fertilization in embryos derived from the oocytes subjected to 22 and 34 h of IVM were evaluated. In the group subjected to 34 h of IVM, high-polarized mitochondria were frequently observed at the periphery of blastomeres. The present results suggest that high mitochondrial activity observed in oocytes after prolonged IVM culture and localization of high-polarized mitochondria at the periphery of blastomeres during early embryonic development may be associated with the low developmental competence in aged bovine oocytes.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Oocitos
/
Bovinos
/
Fertilización In Vitro
/
Adenosina Trifosfato
/
Estrés Oxidativo
/
Mitocondrias
Límite:
Animals
Idioma:
En
Revista:
J Reprod Dev
Asunto de la revista:
MEDICINA REPRODUTIVA
Año:
2014
Tipo del documento:
Article
País de afiliación:
Japón