background:   objective: this study was designed to examine the effects of hp on in-vitro maturation of oocytes and cell death in cumulus cells derived from vitrified-warmed mouse ovaries.   materials and methods: preovulatory follicles were harvested from non-vitrified and vitrified-warmed 6-8 week-old female nmri mouse ovaries and randomly assigned to following groups: non-vitrified (control)...

Oocyte maturation is a key issue of current animal biotechnology. This study was designed to examine the morphodynamics of the cumulus-oocyte association during oocyte maturation. Porcine cumulus-oocyte complexes were recovered from slaughterhouse ovaries; matured in vitro for 0, 24, 36, and 44 h; and evaluated by scanning electron microscopy either combined or not combined with the osmium-dime...

background: leukemia inhibitory factor (lif) is a 45-56 kda glycoprotein that has an important role in proliferation and embryo implantation. its effect on oocyte maturation and how to exert the function remained to be elucidated. methods: immature mice superovulated with human menopausal gonadotropin and germinal vesicle (gv) oocytes were obtained from ovary 48 hours after. gv oocytes were cul...

Oocytes of LT/Sv mice have anomalous cytoplasmic and nuclear maturation. Here, we show that in contrast to the oocytes of wild-type mice, a significant fraction of LT/Sv oocytes remains arrested at the metaphase of the first meiotic division and is unable to undergo sperm-induced activation when fertilized 15 hours after the resumption of meiosis. We also show that LT/Sv oocytes experimentally ...

Polo-like kinase 1 (PLK1) orchestrates multiple events of cell division. Although PLK1 function has been intensively studied in centriole-containing and rapidly cycling somatic cells, much less is known about its function in the meiotic divisions of mammalian oocytes, which arrest for a long period of time in prophase before meiotic resumption and lack centrioles for spindle assembly. Here, usi...

The microtubule-associated protein ASPM (abnormal spindle-like microcephaly-associated) plays an important role in spindle organization and cell division in mitosis and meiosis in lower animals, but its function in mouse oocyte meiosis has not been investigated. In this study, we characterized the localization and expression dynamics of ASPM during mouse oocyte meiotic maturation and analyzed t...

The arrest of meiotic prophase in mammalian oocytes within fully grown follicles is dependent on cyclic adenosine monophosphate (cAMP) regulation. A large part of cAMP is produced by the Gs-linked G-protein-coupled receptor (GPR) pathway. In the present study, we examined whether GPR3 is involved in the maintenance of meiotic arrest in porcine oocytes. Expression and distribution of GPR3 were e...

In human eggs, aneuploidy increases with age and can result in infertility and genetic diseases. Studies in mouse oocytes suggest that reduced centromere cohesion and spindle assembly checkpoint (SAC) activity could be at the origin of chromosome missegregation. Little is known about these two features in humans. Here, we show that in human eggs, inter-kinetochore distances of bivalent chromoso...

background: fat-rich diet may alter oocyte development and maturation and embryonic development by inducing oxidative stress (os) in follicular environment. objective: to investigate the relationship between fat intake and oxidative stress with oocyte competence and embryo quality. materials and methods: in observational study follicular fluid was collected from 236 women undergoing assisted re...

The role of mechanics in numerous biological processes is nowadays recognized, while in others, such as the fertilization process, it is still neglected. In the case of oocytes the description of their mechanical properties could improve the comprehension of the oocyte-spermatozoon interaction and be helpful for application in in vitro fertilization (IVF) clinics. Herein the mechanical properti...