Oocyte-derived bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) are key regulators of follicular development. Here we show that these factors control cumulus cell metabolism, particularly glycolysis and cholesterol biosynthesis before the preovulatory surge of luteinizing hormone. Transcripts encoding enzymes for cholesterol biosynthesis were downregulated in bot...

Background: Oocyte in vitro maturation success rate is still low in compareision to oocyte in vivo maturation. Thus prediction and improvement of oocyte competency are two critical issues in assisted reproductive technology. New insights into oocyte-cumulus cell regulatory loop may assist our optimization of in vitro maturation technique. Maturation and developmental competency of cumulus oocyt...

Glucose is an essential nutrient for mammalian cells. Emerging evidence suggests that glucose within the oocyte regulates meiotic maturation. However, it remains controversial as to whether, and if so how, glucose enters oocytes within cumulus-oocyte complexes (COCs). We used a fluorescent glucose derivative (6-NBDG) to trace glucose transport within live mouse COCs and employed inhibitors of g...

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...

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...

Cumulus cells play an essential role during oocyte maturation and the acquisition of fertilizability and developmental competence. Micro(mi)RNAs can post-transcriptionally regulate mRNA expression, and we hypothesized that miRNA profiles in cumulus cells could serve as an indicator of oocyte quality. Cumulus cell biopsies from cumulus−oocyte−complexes that either yielded a blastocyst or failed ...

Fertilization of the mammalian oocyte requires interactions between spermatozoa and expanded cumulus extracellular matrix (ECM) that surrounds the oocyte. This review focuses on key molecules that play an important role in the formation of the cumulus ECM, generated by the oocyte-cumulus complex. In particular, the specific inhibitors (AG1478, lapatinib, indomethacin and MG132) and progesterone...

The overall objective of this work was to describe whether supplementing fibroblast growth factor 2 (FGF2) during in vitro maturation (IVM) affects cumulus and oocyte maturation and subsequent embryonic development. Supplementing 0.5, 5 or 50 ng/ml FGF2 to cumulus-oocyte complexes (COCs) increased the percentage of oocytes with extruded polar bodies after IVM. Supplementing FGF2 during COC matu...

31 32 In the growing follicle, communication between the oocyte and its surrounding follicular 33 cells is essential for normal oocyte and follicular development. Maturation of the fully34 grown oocyte in vivo is associated with the loss of cumulus cell-oocyte gap junctional 35 communication, preventing entry of meiotic-modulating factors such as cAMP into the 36 oocyte. We have previously show...

BACKGROUND Supplementation of bovine oocyte-cumulus complexes during in vitro maturation (IVM) with 1 μM of docosahexaenoic acid (DHA), C22:6 n-3 polyunsaturated fatty acid, was reported to improve in vitro embryo development. The objective of this paper was to decipher the mechanisms of DHA action. RESULTS Transcriptomic analysis of 1 μM DHA-treated and control cumulus cells after 4 h IVM sh...