Background: The aim of the current study was to assess the mRNA levels of two mitochondria-related genes, including nuclear-encoded NRF1 (nuclear respiratory factor 1), mitochondrial transcription factor A (TFAM), and mitochondrial-encoded cytochrome c oxidase subunit 1 (MT-CO1) genes in various stages of the human oocyte maturation. Methods: Oocytes were obtained from nine infertile women wit...

In mammalian cells, 5-methylcytosine (5-meC) can be transformed into 5-hydroxymethylcytosine (5-hmC) by the methylcytosine dioxygenase TET proteins (TET1, TET2 and TET3). Thymine DNA glycosylase (TDG), a downstream enzyme of TET proteins, not only functions in base excision repair, but also acts as a key enzyme that participates in active DNA demethylation. Here we microinjected exogenous TDG-m...

The recovery of immature oocytes followed by in vitro maturation, fertilization and culture (IVMFC) allows the rescue of biological material of great genetic value for the establishment of genetic resource banks of endangered species. Studies exist on sperm cryopreservation of endangered Mohor gazelle (Gazella dama mhorr), but no work has been carried out yet on oocyte collection, fertilization...

OBJECTIVE To evaluate the integrity of genomic imprinting in oocytes vitrified at the germinal vesicle (GV) stage and in vitro matured (IVM) after thawing. DESIGN Clinical research and application. SETTING University-based fertility center. PATIENT(S) Immature oocytes were donated for research by patients who were included in an intracytoplasmic sperm injection program. INTERVENTION(S) ...

BACKGROUND Oocytes are the female gametes which establish the program of life after fertilization. Interactions between oocyte and the surrounding cumulus cells at germinal vesicle (GV) stage are considered essential for proper maturation or 'programming' of oocytes, which is crucial for normal fertilization and embryonic development. However, despite its importance, little is known about the m...

To study the time- and temperature-dependent survival of ovarian oocytes collected from postmortem carcass, ICR mice were killed and placed for different periods (0, 1, 2, 4, 6, 8 and 10 h) at different temperatures (25°C, 4°C and 37°C). After preservation, oocyte morphology, germinal vesicle (GV) oocyte number, oocyte meiotic maturation percentage, mitochondrial distribution and intracellular ...

Elder women suffer from low or loss of fertility because of decreasing oocyte quality as maternal aging. As energy resource, mitochondria play pivotal roles in oocyte development, determining oocyte quality. With advanced maternal age, increased dysfunctions emerge in oocyte mitochondria, which decrease oocyte quality and its developmental potential. Mitochondria supplement as a possible strate...

BACKGROUND Chromatin configuration of the germinal vesicle (GV) and quality of the cytoplasm are critical factors in achieving oocyte meiotic and developmental capacity during folliculogenesis. Besides gaining new insights into the timing and cellular mechanisms associated with the acquisition and regulation of GV oocyte competence, the domestic cat model was used to examine (i) the relation be...