OBJECTIVE To determine whether the incidence of apoptosis in mature oocyte cumulus cells changes after insemination related to infertility. DESIGN Prospective study. SETTING Public hospital and university. PATIENT(S) One hundred women undergoing in vitro fertilization and embryo transfer (IVF-ET). INTERVENTION(S) Collection of cumulus cells from IVF-ET cycles with different infertility ...

An experimental design was framed to analyse the effect of cumulus oocyte complex (COC) morphology on in vitro maturation of bovine oocytes. Slaughter house derived bovine ovaries from South Indian breeds and crossbred cattle of Kerala were subjected to three retrieval methods to yield different quality grades of oocytes. Based on the number of layers of cumulus cells and ooplasm character, the...

The perivitelline space is the gap between the plasma membrane and the zona pellucida of the oocyte. Although not present in the oocytes in the germinal vesicle stage, the perivitelline space is known to start forming when meiotic maturation resumes and to enlarge in matured oocytes at the metaphase II stage (Kaufman et al., 1989; Okada et al., 1993). Recently, it has been suggested that there ...

In mammals, oocyte acquires a series of competencies sequentially during folliculogenesis that play critical roles at fertilization and early stages of embryonic development. In mouse, chromatin in germinal vesicle (GV) undergoes dynamic changes during oocyte growth and its progressive condensation has been related to the achievement of developmental potential. Cumulus cells are essential for t...

Meiotic maturation of mammalian oocytes is a precisely orchestrated and complex process. Dimethyl sulfoxide (DMSO), a widely used solvent, drug, and cryoprotectant, is capable of disturbing asymmetric cytokinesis of oocyte meiosis in mice. However, in pigs, DMSO's effect on oocyte meiosis still remains unknown. We aimed to evaluate if DMSO treatment will affect porcine oocyte meiosis and the un...

MicroRNA-378 regulates oocyte maturation via the suppression of aromatase in porcine 1 cumulus cells 2 Bo Pan, Derek Toms, Wei Shen, Julang Li 3 Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario 4 Laboratory of Germ Cell Biology, College of Animal Science and Technology, Qingdao 5 Agricultural University, Qingdao, China 6 7 Abbreviated title: Cumulus cell miR-378 i...

OBJECTIVES During ovulation, it has been shown that LH stimulus induces the expression of numerous genes via PKA, p38 MAPK, PI3K and ERK1/2 in cumulus cells and granulosa cells. Our recent study showed that EGF-like factor and its protease (TACE/ADAM17) are required for the activation of EGF receptor (EGFR), cumulus expansion and oocyte maturation of porcine cumulus-oocyte complexes (COCs). In ...

Oocyte maturation is critical for successful fertilization and pregnancy. The mechanism underlying the control of this complex process remain relatively unknown, and even more so the specific mechanism through which oocytes acquire competentce to restrain apoptosis and resume meiosis. Insulin-like Growth Factor 1 (IGF-1) is a growth factor that had been frequently used in inducing oocyte matura...

Substantially less development to the blastocyst stage occurs in vitro than in vivo and this may be due to deficiencies in oocyte competence. Although a large proportion of bovine oocytes undergo spontaneous nuclear maturation, less is known about requirements for proper cytoplasmic maturation. Commonly, supraphysiological concentrations of FSH and LH are added to maturation media to improve cu...

The aim of in vitro maturation oocyte systems is to produce oocytes of comparable quality to those derived in vivo. The present study was designed to examine the surface morphological changes of the cumulus-oocyte complex (COC) and nuclear maturation in a culture system containing pyruvate. Ovaries were obtained from a slaughterhouse and transported to the laboratory within 2 h at 35-39 degrees...