Search results for " Oocytes"
showing 8 items of 8 documents
Autophagy is required for sea urchin oogenesis and early development.
2016
SummaryAutophagy is a major intracellular pathway for the degradation and recycling of cytosolic components. Emerging evidence has demonstrated its crucial role during the embryo development of invertebrates and vertebrates. We recently demonstrated a massive activation of autophagy in Paracentrotus lividus embryos under cadmium stress conditions, and the existence of a temporal relationship between induced autophagy and apoptosis. Although there have been numerous studies on the role of autophagy in the development of different organisms, information on the autophagic process during oogenesis or at the start of development in marine invertebrates is very limited. Here we report our recent …
AN INNOVATIVE STRATEGY IN SELECTING OOCYTES WITH HIGH IMPLANTATION POTENTIALITY FOR INTRACYTOPLASMIC SPERM INJECTION PROCEDURE
2015
The aim of the research was to investigate the apoptosis rate of individual cumulus cell-oocyte complexes (COC), associated to the level of pAKT, to verify the difference between oocytes who produce embryos able to reach the blastocyst stage compared with embryos arrested during the in vitro culture. It was demonstrated that DNA fragmentation in cumulus cells was remarkably lower in patients who achieved a pregnancy after ICSI cycles, related to the quality of oocytes and embryos1,2. AKT pathway plays a critical role in the regulation of cell survival, and most growth factors activate this pathway3. The study focused on 53 patients, involved after informed consent. In this prospective and r…
Apoptosis and pAKT levels in cumulus cells of patients undergoing in vitro fertilization program with specific polymorphisms of gonadotropins and the…
2016
Study question Is there a difference in oocyte competence among patients with different gonadotrophin polymorphisms, after ovarian stimulation with r-FSH? Summary Answer Higher DNA Fragmentation Index and cleaved caspase-3 related to lower level of pAKT has been observed in patients with specific gonadotrophin polymorphism (FSHR and LHB). What is known already • In our experience, the DFI, the percentage of cleaved caspase-3 and the pAKT on cumulus cells can be used as molecular markers of oocyte competence; • The polymorphic variant of LHB is characterized by an extra glycosylation signal into the β subunit. This molecular variation influences the pharmacokinetic properties of v-betaLH, sh…
Multiple actions of fenamates and other nonsteroidal anti-inflammatory drugs on GABAA receptors
2019
The nonsteroidal anti-inflammatory drug (NSAID) niflumic acid, a fenamate in structure, has many molecular targets, one of them being specific subtypes of the main inhibitory ligand-gated anion channel, the GABA(A) receptor. Here, we report on the effects of other fenamates and other classes of NSAIDs on brain picrotoxinin-sensitive GABA A receptors, using an autoradiographic assay with [S-35]TBPS as a ligand on mouse brain sections. We found that the other fenamates studied (flufenamic acid, meclofenamic acid, mefenamic acid and tolfenamic acid) affected the autoradiographic signal at low micromolar concentrations in a facilitatory-like allosteric fashion, i.e., without having affinity to …
Loss-of-function maternal-effect mutations of PADI6 are associated with familial and sporadic Beckwith-Wiedemann syndrome with multi-locus imprinting…
2020
Abstract Background PADI6 is a component of the subcortical maternal complex, a group of proteins that is abundantly expressed in the oocyte cytoplasm, but is required for the correct development of early embryo. Maternal-effect variants of the subcortical maternal complex proteins are associated with heterogeneous diseases, including female infertility, hydatidiform mole, and imprinting disorders with multi-locus imprinting disturbance. While the involvement of PADI6 in infertility is well demonstrated, its role in imprinting disorders is less well established. Results We have identified by whole-exome sequencing analysis four cases of Beckwith-Wiedemann syndrome with multi-locus imprintin…
New molecular markers for the evaluation of gamete quality.
2013
Purpose: Only 30 % of IVF cycles result in a pregnancy, so that multiple embryos need to be replaced, per treatment cycle, to increase pregnancy rates, resulting in a multiple gestation rate of 25 %. The use of new markers in the gamete selection, could reduce the number of the oocytes to be fertilized and embryos to be produced, but the tools to evidence the gamete competence remain unavailable and more studies are needed to identify bio-markers to select the best oocyte and sperm to produce embryos with higher implantation potentiality. Methods: To define oocyte competence, the apoptosis of the surrounding cumulus cells and the oxygen consumption rates for individual oocytes before fertil…
Specific binding of VegT mRNA localization signal to membranes in Xenopus oocytes
2021
Abstract We have studied the interaction of a VegT mRNA localization signal sequence with the membranes of the mitochondrial cloud in Xenopus oocytes, and the binding of the VegT mRNA signal sequence to the lipid raft regions of the vesicles bounded by ordered and disordered phospholipid bilayers. RNA preference for the membranes of the mitochondrial cloud was confirmed using microscopy of a fluorescence resonance energy transfer from RNA molecules to membranes. Our studies show that VegT mRNA has a higher affinity for ordered regions of lipid bilayers. This conclusion is supported by the dissociation constant measurements for RNA-liposome complex and the visualization of the FRET signal be…
Apoptosis in human unfertilized oocytes after intracytoplasmic sperm injection
2005
Objective To investigate the presence of programmed cell death in unfertilized oocytes after intracytoplasmic sperm injection (ICSI), assuming that previous apoptotic events could be correlated with the fertilization failure. Design Comparison of the rate of DNA fragmentation in human oocytes at different stages of maturation soon after pick-up (control) and in unfertilized oocytes after ICSI treatment. Setting In vitro fertilization (IVF) laboratory with extensive ICSI experience. Patient(s) Sixty-three patients undergoing assisted fertilization by ICSI. Intervention(s) Terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay and anticaspase-3 cleaved…