The morphology of canine cumulus-oocyte complexes (COCs) before puberty is still unknown. Therefore, the aim of our study was to elucidate the morphological characteristics of pre-pubertal oocytes and cumulus cells by light microscopy, scanning electron microscopy and transmission electron microscopy. The pre-pubertal oocyte was characterized by accumulation of lipid yolk droplets in the cytopl...

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...

Cumulus clouds involve processes on a vast range of scales—including cloud droplets, turbulent mixing, and updrafts and downdrafts—and it is often difficult to determine how processes on different scales interact with each other. In this article, several multiscale asymptotic models are derived for cumulus cloud dynamics in order to (i) provide a systematic scale analysis on each scale and (ii)...

(1) Background: The binding sites of melatonin, as a multifunctional molecule, have been identified in human, porcine, and bovine samples. However, the binding sites and mechanisms of melatonin have not been reported in sheep; (2) Methods: Cumulus-oocyte complexes (COCs) were cultured in TCM-199 supplemented with melatonin at concentrations of 0, 10-3, 10-5, 10-7, 10-9, and 10-11 M. Melatonin r...

BACKGROUND The production of competent oocytes depends on a bi-directional communication between the oocyte and cumulus cells. The goal of this study was to determine whether simple parameters monitored in cumulus cells from individual human oocytes have any predictive value, and thus correlate with clinically relevant parameters. METHODS 97 cumulus-oocyte complexes were recovered from 31 pat...

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...

Paracrine factors secreted by the oocyte regulate a broad range of cumulus cell functions. Characteristically, cumulus cells have a low incidence of apoptosis and we proposed that this is due to oocyte-secreted factors acting in an anti-apoptotic manner. Bovine cumulus-oocyte complexes (COC) were aspirated from abattoir-derived ovaries and oocytectomized (OOX) by microsurgical removal of the oo...

cAMP and intracellular Ca2+ are important second messengers involved in mammalian follicular growth and oocyte meiotic maturation. We investigated the capacity of the neurohormone serotonin (5-hydroxytryptamine, 5-HT) to regulate intracellular cAMP and Ca2+ in mouse oocytes and surrounding cumulus cells. On the basis of a reverse transcription-polymerase chain reaction study, 5-HT7 receptor mRN...

The role of gossypol in the cumulus expansion of oocyte-cumulus complexes (OCC) isolated from large antral porcine follicles was investigated. Marked suppression of cumulus expansion stimulated with follicle-stimulating hormone (FSH) and epidermal growth factor (EGF) was observed in the presence of different concentrations of gossypol. Comparable inhibitory effects were obtained in the presence...

PTX3 is a prototypic long pentraxin that plays a non-redundant role in innate immunity against selected pathogens and in female fertility. Here, we report that the infertility of Ptx3(-/-) mice is associated with severe abnormalities of the cumulus oophorus and failure of in vivo, but not in vitro, oocyte fertilization. PTX3 is produced by mouse cumulus cells during cumulus expansion and locali...