Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte...

The oocyte maturation includes nuclear maturation and cytoplasmic maturation before fertilization. Moreover, the oocyte nucleus, the cytoplasm and other cell organelles occur changes, zona pellucida (ZP) synchronously undergoes biochemical and structural modifications in the final maturation phase of oocyte prior to fertilization (ZP maturation). It is reported that ZP modifications, such as gl...

Background: Mammalian oocyte undergoes a series of structural nuclear modulations during maturation in order to obtain full competence to support fertilization and early embryonic development. Microtubules are major cytoskeleton components and have pivotal modulators for chromosomal movement, and it has been shown that partial or immature spindle organization may compromise correct ploidy of th...

Oocyte cytoplasmic maturation is influenced by the quantity of synthesized RNA and proteins accumulated and stored during growth. Transcriptional repression and degradation of transcripts occur during oocyte nuclear maturation, and prolonged transcriptional arrest might compromise RNA stores for early development. RNA quantification of key genes in oocytes might be valuable when setting up in v...

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...

Pregnancy success results from the interaction of multiple factors, among them are folliculogenesis and early embryonic development. Failure during these different processes can lead to difficulties in conception. Alternatives to overcome these problems are based on assisted reproductive techniques. Extracellular vesicles are cell-secreted vesicles present in different body fluids and contain b...

In vivo-matured cumulus-oocyte complexes are valuable models in which to assess potential biomarkers of rabbit oocyte quality that contribute to enhanced IVM systems. In the present study we compared some gene markers of oocytes and cumulus cells (CCs) from immature, in vivo-matured and IVM oocytes. Moreover, apoptosis in CCs, nuclear maturation, mitochondrial reallocation and the developmental...

Objective The success rates of assisted reproduction technology (ART) could be developed with the improvement of ovarian stimulation protocols as well as the optimization of final oocyte maturation. The goal of this study was to compare oocyte maturation, fertilization and pregnancy rates among women with concomitant FSH administration at the time of hCG trigger and the hCG trigger alone. Mater...