OBJECTIVE To investigate the role of the cumulus cells and the cumulus matrix in affecting the penetrability, morphology, acrosome reaction, and motility of human spermatozoa penetrating the cumulus oophorus. DESIGN Controlled experimental laboratory study. SETTING University gynecology unit. PATIENT(S) Women undergoing assisted reproduction treatment and men visiting the subfertility cli...

The two principal functions of ovarian follicles are developmental and endocrine. The cumulus cells surrounding the oocyte are specialized to serve the development of the oocyte and steroidogenesis is a principal role of mural granulosa cells that line the follicle wall. The findings in this report demonstrate that oocytectomy or treatment with an inhibitor of SMAD2/3 activation results in decr...

Cumulus oocyte complex (COC) expansion is induced through hyaluronic acid production and accumulation of proteins of the inter-alpha-trypsin inhibitor family in the gonadotropin-stimulated cumulus cells. Link protein, a glycoprotein found in cartilage, interacts specifically with hyaluronic acid and stabilizes the binding of proteoglycan monomers to hyaluronic acid to form aggregates. The aim o...

In ovarian antral follicles cumulus cells (approximately 1,000/follicle) closely surround the oocyte, and mural granulosa cells (approximately 50,000/follicle) are distributed at the periphery. Previous work (Salustri, A., Yanagishita, M., and Hascall, V. C. (1990) Dev. Biol. 138, 26-32) showed that oocytes produce a factor(s) which stimulates hyaluronic acid (HA) synthesis by cumulus cells dur...

Buffalo ovaries were collected from a slaughter house and cumulus cells oocytes complexes (COCs) were recovered for preparation of 2-D, 4-D, 6-D and 8-D monolayer. Cumulus cells were stripped off by repeated pipetting into TCM-199 medium supplemented with 10% FCS. Approximately 2x106/ml cumulus cell were transferred in 100 μl drops of culture medium and incubated in humidifi ed atmosphere of 5%...

Background: There is a considerable numbers of buffalo (Bubalus bubalis) in Iran which have an important role in rural life. The reproductive performance of buffalo is lower than cow. Co-culture with somatice cells improved the maturation rate of most of the species. The aim of the present study was to evaluate the effect of bovine cumulus co-culture on post fertilization development of buffalo...

Communication between oocytes and their companion somatic cells promotes the healthy development of ovarian follicles, which is crucial for producing oocytes that can be fertilized and are competent to support embryogenesis. However, how oocyte-derived signaling regulates these essential processes remains largely undefined. Here, we demonstrate that oocyte-derived paracrine factors, particularl...

Normal ovulation in mice requires PG-endoperoxide synthase 2 (cyclooxygenase-2; COX-2) expression. This study examined the role of the oocyte and other factors in regulating steady state levels of COX-2 messenger RNA (mRNA) in granulosa cells. Multiphasic changes in the expression pattern of COX-2 mRNA were found, with peaks of expression 4 and 12 h after hCG treatment. Changes in relative expr...

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 ...

A typical mammalian egg is surrounded by an outer layer of about 3,000 cumulus cells embedded in an extracellular matrix rich in hyaluronic acid. A current, widely proposed model is that the fertilizing sperm, while it is acrosome intact, passes through the cumulus cell layer and binds to the egg zona pellucida. This current model lacks a well-supported explanation for how sperm penetrate the c...