The importance of mitochondrial metabolic activity and mitochondrial DNA replication during oocyte maturation in vitro on oocyte quality and subsequent embryo developmental competence

Hongshan Ge, Theodore L Tollner, Zhen Hu, Mimi Dai, Xiaohe Li, Heqin Guan, Dan Shan, Xiuju Zhang, Jieqiang Lv, Changjiang Huang, Qiaoxiang Dong

Research output: Contribution to journalArticle

65 Scopus citations

Abstract

Mitochondrial metabolic capacity and DNA replication have both been shown to affect oocyte quality, but it is unclear which one is more critical. In this study, immature oocytes were treated with FCCP or ddC to independently inhibit the respective mitochondrial metabolic capacity or DNA replication of oocytes during in vitro maturation. To differentiate their roles, we evaluated various parameters related to oocyte maturation (germinal vesicle break down and nuclear maturation), quality (spindle formation, chromosome alignment, and mitochondrial distribution pattern), fertilization capability, and subsequent embryo developmental competence (blastocyst formation and cell number of blastocyst). Inhibition of mitochondrial metabolic capacity with FCCP resulted in a reduced percent of oocytes with nuclear maturation; normal spindle formation and chromosome alignment; evenly distributed mitochondria; and an ability to form blastocysts. Inhibition of mtDNA replication with ddC has no detectable effect on oocyte maturation and mitochondrial distribution, although high-dose ddC increased the percent of oocytes showing abnormal spindle formation and chromosome alignment. ddC did, however, reduce blastocyst formation significantly. Neither FCCP nor ddC exposure had an effect on the rate of fertilization. These findings suggest that the effects associated with lower mitochondrial DNA copy number do not coincide with the effects seen with reduced mitochondrial metabolic activity in oocytes. Inhibiting mitochondrial metabolic activity during oocyte maturation has a negative impact on oocyte maturation and subsequent embryo developmental competence. A reduction in mitochondrial DNA copy number, on the other hand, mainly affects embryonic development potential, but has little effect on oocyte maturation and in vitro fertilization.

Original languageEnglish (US)
Pages (from-to)392-401
Number of pages10
JournalMolecular Reproduction and Development
Volume79
Issue number6
DOIs
StatePublished - Jun 2012

ASJC Scopus subject areas

  • Genetics
  • Developmental Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'The importance of mitochondrial metabolic activity and mitochondrial DNA replication during oocyte maturation in vitro on oocyte quality and subsequent embryo developmental competence'. Together they form a unique fingerprint.

  • Cite this