Delayed ovulation and delayed fertilization can lead to reduced developmental competence of the oocyte. In contrast to the consequences of postovulatory aging of the oocyte, hardly anything is known about the molecular processes occurring during oocyte maturation if ovulation is delayed (preovulatory aging). We investigated several aspects of oocyte maturation in two models of preovulatory agin...

Background This research was conducted to assess preantral follicle development in fibrin alginate matrix following ovarian tissue vitrification MaterialsAndMethods Ovaries of 13-day-old NMRI female mice were removed and placed in control and vitrification groups. Vitrification group ovaries were transferred in media containing ethylene glycol, dimethyl sulphoxide, and sucrose then were plunged...

background   objective:   materials and methods   results   conclusion   key words:   . vitrification, viability, in vitro maturation, gvbd, oocyte, mouse : these results suggest that step-wise vitrification of gvbd oocytes as compared to single step vitrification was better in the rate of survival and in vitro maturation of oocytes. : all non-vitrified oocytes were viable after 24 hr; however,...

We sought to investigate whether miR-378 plays a role in cumulus cells and whether the manipulation of miRNA levels in cumulus cells influences oocyte maturation in vitro. Cumulus-oocyte complexes (COCs) from ovarian follicles had significantly lower levels of precursor and mature miR-378 in cumulus cells surrounding metaphase II (MII) oocytes than cumulus cells surrounding germinal vesicle (GV...

The present study has evaluated the association of growth differentiation factor9 (GDF9) and bone morphogenetic protein15 (BMP15) mRNA expression in cumulus-oocyte complexes (COCs) of buffalo ovary during in vitro maturation (IVM). GDF9 and BMP15 are expressed specifically in mammalian oocytes and also participate in cumulus-oocyte crosstalk. Quantitative real-time polymerase chain reaction (qR...

Background: Cryopreservation of ovaries is an important technique in assisted reproduction technology. Physical forces like hydrostatic pressure have a pivotal role in reproduction systems. Due to changes in intrafollicular pressure during ovulatory process, this study designed to examine the effects of hydrostatic pressure on oocyte maturation and cell death in cumulus cells from cryopreserved...

BACKGROUND Excessive nerve growth factor (NGF) is commonly found in the follicular fluid of patients with polycystic ovary syndrome (PCOS). Furthermore, oocytes from PCOS patients exhibit lower developmental competence. The purpose of this study was to explore the association between excessive NGF and low oocyte competence in vitro. METHODS Excessive NGF was added to mouse cumulus oocyte comp...

background: oocyte maturation and subsequent in vitro production (ivp) of embryos are affected by diverse groups of chemicals in maturation medium which are needed for successful mammalian oocyte maturation during which the dramatic cytoplasmic and nuclear reprogramming events take place. this study was designed to evaluate the effects of protein source (fetal bovine serum, fbs, and bovine seru...

Cumulus cells (CC) surround the oocyte and are coupled metabolically through regulation of nutrient intake. CC removal before in vitro maturation (IVM) decreases bovine oocyte developmental competence without affecting nuclear meiotic maturation. The objective was to investigate the influence of CC on oocyte cytoplasmic maturation in relation to energy metabolism. IVM with either cumulus-enclos...