Acquisition of oocyte developmental competence needs to be understood to improve clinical outcomes of assisted reproduction. The stimulation of cumulus cell concentration of cyclic adenosine 3'5'-monophosphate (cAMP) by pharmacological agents during in vitro maturation (IVM) participates in improvement of oocyte quality. However, precise coordination and downstream targets of cAMP signaling in ...

BACKGROUND Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in women. The developmental competence of oocytes and embryos in PCOS patients is reduced to a certain extent (comparing to non-PCOS patients, the high quality embryo rate was decreased by 16% from the data of our centre) during the in vitro fertilization (IVF) process. Cross-talk between the oocyte and cum...

Mammalian oocytes are deficient in their ability to carry out glycolysis. Therefore, the products of glycolysis that are necessary for oocyte development are provided to oocytes by companion cumulus cells. Mouse oocytes secrete paracrine factors that promote glycolysis in cumulus cells. The objective of this study was to identify paracrine factors secreted by oocytes that promote glycolysis and...

BACKGROUND Oocyte secreted factors (OSFs), including growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), play an important role in the process of follicular development and oocyte maturation. Since OSFs are expressed in oocytes and cumulus granulosa cells, the aim of the present study was to explore whether the expression levels of GDF9 and BMP15 mRNAs in cumulus g...

An age-dependent acceleration of apoptosis occurs in female germ cells (oocytes), and this requires communication between the oocyte and its surrounding somatic (cumulus) cells. Here we show in aged mice that ceramide is translocated from cumulus cells into the adjacent oocyte and induces germ cell apoptosis that can be prevented by sphingosine-1-phosphate. Trafficking of ceramide requires gap ...

Cumulus oophorus cells play an essential role in oocyte development. They are also widely employed as donor cells for cloning by somatic cell nuclear transfer. Our previous studies revealed that Cbx4 mRNA was overexpressed in cloned two-cell embryos. These data indicated that CBX4 may regulate normal cumulus cell differentiation and that its overexpression in clones could contribute to aberrant...

Few studies demonstrate at a biochemical level the metabolic profile of both cumulus cells and the oocyte during maturation. The aim of the present study was to investigate the differential participation of enzymatic activity in cumulus cells and in the oocyte during in vitro maturation (IVM) by studying the activity of enzymes involved in the control of amino acid metabolism, alanine aminotran...

Oocytes and their companion somatic cells maintain a close association throughout oogenesis and this association is essential for normal oocyte and follicular developmenL This review summarizes current concepts of the role of the somatic cells in the regulation of mammalian oocyte growth, the maintenance of meiotic arrest, the induction of oocyte maturation, and the acquisition of full embryoni...

BACKGROUND: The purpose of this study was to localize the expression of steroid sulfatase (STS) in cumulus cells and to determine the relationship between STS mRNA expression and the serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol and progesterone. METHODS: The subject group included 49 women (29 to 44 years old) for whom in vitro fertilization treatment ...

the aim of this study was to determine the quality of cumulus-oocyte-complexes (cocs) and the effects of bovine serum albumin (bsa) supplementation on in vitro maturation and fertilization rate of buffalo oocytes. cocs were collected from slaughterhouse buffalo ovaries by aspiration method. only normal grades cocs were matured for 48 hours in tcm-199 media. two groups were created: one for the ...