The expression of glucose transporters 1, 2, 3 and 4 was evaluated in human oocytes and polyploid preimplantation embryos. Only glucose transporter 1 (GLUT-1) isoform was detected in oocytes and in 2-12-cell stage embryos. Glucose uptake was markedly increased in embryos as compared to oocytes (19.7 +/- 3.4 pmol/min/embryo and 2.3 +/- 0.3 pmol/min/oocyte), and GLUT-1 was inhibited by cytochalas...

In mammalian oocytes, the maintenance of meiotic prophase I arrest prior to the surge of LH that stimulates meiotic maturation depends on a high level of cAMP within the oocyte. In mouse and rat, the cAMP is generated in the oocyte, and this requires the activity of a constitutively active, Gs-linked receptor, GPR3 or GPR12, respectively. To examine if human oocyte meiotic arrest depends on a s...

background: the aim of this study was to assess effects of cysteamine as an anti-oxidant on rate of in vitro maturation of oocyte and determination of its effects on spindle size and shape. methods: pre-mature mice were primed with pregnant mare stimulating gonadotrophin (pmsg) and germinal vesicle (gv) stage oocytes were obtained 48 h after. the oocytes were cultured in tissue culture medium (...

Type I inositol 1,4,5-trisphosphate-sensitive receptors (InsP(3)R) are expressed in human oocytes and may be involved in operating the Ca(2+) release triggered by the fertilizing sperm. This study examines the contribution of type I InsP(3)R in operating Ca(2+) release in human oocytes secondary to InsP(3) itself, using a specific function-blocking antibody in conjunction with photolytic releas...

Oocyte developmental competence is one of the determining factors that in?uence outcomes an IVF cycle regarding ability a female gamete to reach maturation and be fertilized. A non-invasive approach using proteomic analysis oocyte cumulus cells (CCs) can used as method predict viability could potentially function molecular predictors for program prognosis. Our study was aimed at quantifying pro...

Parthenogenetic activation of human oocytes obtained from infertility treatments has gained new interest in recent years as an alternative approach to create embryos with no reproductive purpose for research in areas such as assisted reproduction technologies itself, somatic cell, and nuclear transfer experiments and for derivation of clinical grade pluripotent embryonic stem cells for regenera...

BACKGROUND In vitro maturation (IVM) is a promising treatment option for certain infertile women. Nowadays, with the aid of PolScope, it has become possible to evaluate zona pellucida (ZP) characteristics as a parameter of oocyte quality. Moreover, quality of oocytes can be influenced by many factors, such as patient's age. The PolScope system is a non-invasive technique to assess birefringent ...

Oocyte maturation in rodents is characterized by a dramatic reorganization of the endoplasmic reticulum (ER) and an increase in the ability of an oocyte to release Ca(2+) in response to fertilization or inositol 1,4,5-trisphosphate (IP(3)). We examined if human oocytes undergo similar changes during cytoplasmic meiotic maturation both in vivo and in vitro. Immature, germinal vesicle (GV)-stage ...

This study was conducted to evaluate the preimplantation embryonic potential of adult somatic cells from an infertile man using an interspecies bioassay for quality control and also to create human embryos via somatic cell nuclear transfer (SCNT). Skin tissue was biopsied from infertile man to obtain fibroblast cells. These cells were fused with both enucleated bovine oocytes obtained commercia...

The cryopreservation of immature GV oocytes by vitrification is offering attractive perspectives, since they represent an important pool of germ cells for women undergoing IVM cycles, or at risk of infertility for OHSS or PCOs, particularly those poor responders to gonadotropin stimulation, or in case of cancer. Therefore, it becomes necessary to optimize both cryopreservation technique as well...