Laboratoire dEylau

Paris, France

Laboratoire dEylau

Paris, France
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Guerin P.,VetAgro Sup | Menezo Y.,UNILABs | Menezo Y.,Laboratoire dEylau
Zygote | Year: 2011

The culture of early preimplantation stage embryo is still delicate and the metabolic pathways of embryos are not completely understood. Embryo needs are evolutionary during the preimplantation development, consequently it is difficult to meet embryo needs in vitro. Culture conditions have to respect several physical and chemical equilibria: such as redox potential, pH, osmotic pressure, metabolic flux of energetic compounds, endogenous pools of amino acids and transcripts, etc. Embryo culture media are generally supplemented with amino acids, glucose, other energetic metabolites and antioxidant compounds, vitamin, and growth factors etc. Furthermore autocrine and paracrine regulation of embryo development probably exist. In fact embryo culture conditions have to be as non-toxic as possible. Various types of co-culture systems have been devised to overcome these problems. Complex interrelations exist between embryos and co-cultured cells. The beneficial effects of co-cultured cells may be due to continuous modifications of the culture medium, i.e. the elimination of toxic compounds and/or the supply of embryotrophic factors. Copyright © Cambridge University Press 2010.

Montjean D.,Institute Pasteur Paris | Montjean D.,Laboratoire dEylau | Ravel C.,University of Rennes 1 | Benkhalifa M.,Laboratoire dEylau | And 4 more authors.
Fertility and Sterility | Year: 2013

Objective To characterize a potential genetic cause for methylation errors described in oligozoospermia. Design Analysis of PEG1/MEST-DMR and H19-DMR methylation level in sperm, in parallel with the study of several genes on the Y chromosome, DNMT3A, and DNMT3L. Clinical outcome was also looked at regarding PEG1/MEST-DMR and H19-DMR methylation level in sperm. Setting Research and diagnostic laboratories. Patient(s) One hundred nineteen normospermic and 175 oligozoospermic men consulting for couple infertility. Intervention(s) We studied PEG1/MEST-DMR and H19-DMR methylation profiles in 294 men. We searched for Y chromosome gene aberrations and for mutations in both DNMT3A and DNMT3L genes in men showing epimutations. Assisted reproductive technology (ART) outcomes were also investigated. Main Outcome Measure(s) Sperm samples were collected from 294 volunteers for genomic DNA isolation that was used to study methylation profiles in imprinted loci and Y chromosome SMCY, DNMT3A, and DNMT3L genes. Pregnancy rate was also studied after ART treatment using sperm showing epimutations. Result(s) Epimutations in H19-DMR and PEG1/MEST-DMR were found in 20% and 3% of oligozoospermic men, respectively. We identified an amino acid change in DNMT3A in one case and in DNMT3L in eight men with altered methylation profiles. No mutations were detected in SMCY or in selected Y chromsome genes. No correlation between ART outcome and epimutations was found. Conclusion(s) We observed epimethylations in spermatozoa of oligozoospermic individuals, but no association was found with genetic variants or in the ART outcome. © 2013 by American Society for Reproductive Medicine.

Montjean D.,Advanced Technology Laboratory | Montjean D.,Laboratoire dEylau | Montjean D.,Institute Pasteur Paris | Montjean D.,University Pierre and Marie Curie | And 11 more authors.
Fertility and Sterility | Year: 2011

Objective: To investigate the relationship between MTHFR and MTRR genetic variants with respect to both blood plasma homocysteine concentration and sperm counts. Design: Polymerase chain reaction followed by specific enzymatic digestion to determine the genotype of the individuals and blood plasma homocysteine quantification by high-performance liquid chromatography. Setting: Research laboratory. Patient(s): Two hundred sixty-eight men seeking infertility counseling and 254 partners of infertile women. Intervention(s): We studied three MTHFR (c.1286A→C, c.665C→T and c.203G→A) and two MTRR (c.66A→G and c.524C→T) single-nucleotide polymorphisms and characterized sperm parameters in both oligozoospermic and normospermic men. A cohort of 522 men was examined for this study. A subgroup of 103 men was constituted for quantification of Hcy levels. Main Outcome Measure(s): Semen samples were collected for determinations of sperm concentration, motility, and morphology according to World Health Organization guidelines as well as for DNA isolation. Blood samples of the corresponding individuals were obtained to quantify plasma homocysteine levels. Result(s): We did not observe a relationship between homocysteinemia and sperm counts. The MTHFR c.665C→T variant is associated with mild hyperhomocysteinemia in blood plasma in the TT homozygous state. Conclusion(s): No association was found between MTHFR/MTRR genetic variants and sperm counts. Although no association was observed with reduced sperm counts, the MTHFR 665TT genotype is associated with a significant increase in blood plasma homocysteine levels. © 2011 American Society for Reproductive Medicine, Published by Elsevier Inc.

Menezo Y.,Laboratoire dEylau | Menezo Y.,Laboratoire Dynabio | Pluntz L.,Laboratoire dEylau | Chouteau J.,Oriade | And 5 more authors.
Reproductive BioMedicine Online | Year: 2011

Serum and follicular fluid zinc concentrations were investigated in patients undergoing assisted reproductive treatment. No correlation was found between zinc and oestradiol concentrations in serum. At the time of oocyte retrieval, zinc concentrations in follicular fluid were significantly lower than serum concentrations (P < 0.0001). The expression of the two families of zinc transporters, ZnT and ZiP, as well as the metal regulatory transcription factors, MTF1 and 2, and metallothioneins, which are both involved in regulatory aspects of zinc transport, was assayed in cumulus cells and in germinal-vesicle oocytes. Most of the zinc transporters, metallothioneins and metal regulatory transcription factor are expressed in oocytes and not in cumulus cells. This may indicate an important role for zinc, in particular with potential linking to genome stability during early embryonic development. In contrast, cumulus cells seem to be at the end of their life's journey, with weak expression of transcriptional activity linked to cellular housekeeping. © 2011 ALPHA Scientists in Reproductive Medicine and the European Society of Human Reproduction and Embryology. Published by Elsevier Ltd. All rights reserved.

Grzegorczyk-Martin V.,Center Hospitalier des 4 Villes | Khrouf M.,Center Hospitalier des 4 Villes | Bringer-Deutsch S.,Center Hospitalier des 4 Villes | Mayenga J.-M.,Center Hospitalier des 4 Villes | And 4 more authors.
Gynecologie Obstetrique Fertilite | Year: 2012

Objective: To evaluate the results of controlled ovarian hyperstimulation (COH) for IVF in patients with low anti-Müllerian hormone (AMH) and normal basal follicle stimulating hormone (FSH) and Estradiol levels (≤ 50 pg/mL). Patients and methods: A retrospective cohort study including 704 patients for whom AMH and FSH levels (measured between days 3 and 5 of the menstrual cycle) were available, is performed in the IVF center at the Sèvres Hospital (France). Three groups are designed and analyzed: group 1 with AMH less or equal to 2 ng/mL and FSH less or equal to 10 mUI/mL (study group), Group 2 with AMH greater than 2 ng/mL and FSH less or equal to 10 mUI/mL (control group) and Group 3 with AMH less or equal to 2 ng/mL and FSH greater than 10 mUI/mL (group with decreased ovarian reserve). Results: IVF outcome for patients from the study group is significantly worse than that of the second but not than that of the third group. In the first group, the number of retrieved oocytes, the number of total obtained embryos, the clinical pregnancy rate and the live birth rate are significantly lower than in the second group; moreover, there are more cancelled cycles because of poor response in the first group. There is no difference with the third group. Discussion and conclusions: This study shows that women with a low baseline AMH have a similar response to COH to the poor responders patients with a decreased ovarian reserve revealed by an elevated FSH level. Thus, when a woman undergoing IVF cycle presents a low AMH, she might be considered as a poor responder patient regardless of the FSH level and, although the clinical pregnancy rate is not so disappointing (18%), the couple should be informed of a higher risk of cycle cancellation. © 2011 Elsevier Masson SAS. Tous droits réservés.

Menezo Y.,Laboratoire dEylau | Dale B.,Center for Assisted Fertilization | Cohen M.,Clinique Natecia
Zygote | Year: 2010

The genome of all cells is protected at all times by mechanisms collectively known as DNA repair activity (DRA). Such activity is particularly important at the beginning of human life, i.e. at fertilization, immediately after and at the very onset of embryonic development. DRA in early development is, by definition, of maternal origin: the transcripts stored during maturation, need to control the integrity of chromatin, at least until the maternal/zygotic transition at the 4- to 8-cell stage in the human embryo. Tolerance towards DNA damage must be low during this critical stage of development. The majority of DNA damage is due to either apoptosis or reactive oxygen species (ROS). Apoptosis, abortive or not, is a common feature in human sperm, especially in oligoasthenospermic patients and FAS ligand has been reported on the surface of human spermatozoa. The susceptibility of human sperm to DNA damage is well documented, particularly the negative effect of ROS (Kodama et al., 1997; Lopes et al., 1998a, b) and DNA modifying agents (Zenzes et al., 1999; Badouard et al., 2007). DNA damage in sperm is one of the major causes of male infertility and is of much concern in relation to the paternal transmission of mutations and cancer (Zenzes, 2000; Aitken et al., 2003; Fernández-Gonzalez, 2008). It is now clear that DNA damaged spermatozoa are able to reach the fertilization site in vivo (Zenzes et al., 1999), fertilize oocytes and generate early embryos both in vivo and in vitro. The effect of ROS on human oocytes is not as easy to study or quantify. It is a common consensus that the maternal genome is relatively well protected while in the maturing follicle; however damage may occur during the long quiescent period before meiotic re-activation (Zenzes et al., 1998). In fact, during the final stages of follicular growth, the oocyte may be susceptible to damage by ROS. With regards to the embryo there is active protection against ROS in the surrounding environment i.e. in follicular and tubal fluid (El Mouatassim et al., 2000; Guerin et al., 2001). DNA repair activity in the zygote is mandatory in order to avoid mutation in the germ line (Derijck et al., 2008). In this review we focus on the expression of mRNAs that regulate DNA repair capacity in the human oocyte and the mechanisms that protect the embryo against de novo damage. © 2010 Cambridge University Press.

Objectives: To study the evolution of subendometrial vascularization flow index (VFI) in controlled ovarian hyperstimulation (COH + IIU) cycles and compare its dynamic changes in pregnant and non pregnant women. Patients and methods: This is a retrospective study on 61 couples. To determine the profile of IVF just before ovulation, patients had 3D-Power Doppler angiography (3D-PDA) in this precise preovulatory phase. Results: We observed a decreasing profile of VFI in 52% (32/61) of the main group cycles, in 45% (14/31) of the subgroup with spontaneous peak of LH (luteinizing hormone), and in 60% (18/30) of the hCG (human chorionic gonadotropin) trigger subgroup. There were ten conceptions, (10/61, 16.4%), including eight (8/32, 30%) that were associated with a decreasing profile of VFI versus two (2/29, 7%) that were associated with an increasing profile (NS). In the detection of LH peak subgroup, we observed five conceptions (5/14, 36%) associated with a decreasing profile versus one conception (1/17, 6%) associated with an increasing profile of VFI (OR: 8.3; confidence interval [CI] 95%: 0.8-444; P = 0.06 in favor of a of decreasing VFI profile). In the hCG subgroup, there were three conceptions in the decreasing VFI profile (3/18, 17%) and one conception with increasing VFI (1/12, 17%, P = 0.6). Discussion and conclusion: In controlled ovarian hyperstimulation, a decreasing VFI profile is more common compared to an increasing one. Such au profile seems to be associated with a higher conception rate in cycles with spontaneous LH surge. © 2011 Elsevier Masson SAS. All rights reserved.

Montjean D.,Advanced Technology Laboratory | Montjean D.,Laboratoire dEylau | De La Grange P.,GenoSplice Technology | Gentien D.,University Pierre and Marie Curie | And 6 more authors.
Journal of Assisted Reproduction and Genetics | Year: 2012

Purpose: Investigate in what extent sperm transcriptome of infertile men is different from that of fertile individuals. Methods: Semen samples were collected for determination of sperm parameters as well as for RNA isolation. Gene expression profile was investigated in spermatozoa of 8 infertile and 3 fertile men by microarray analysis using the Affymetrix Chip HG-U133 Plus 2.0. Result(s): We observed up to 33-fold reduction expression of genes involved in spermatogenesis and sperm motility. Furthermore, there is an important decrease in expression of genes involved in DNA repair as well as oxidative stress regulation. In this study, we also show a striking drop in expression of histone modification genes. Conclusion(s): We found that transcription profile in germ cells of men with idiopathic infertility is different from that of fertile individuals. Interestingly, about 15% of the regulated genes (Eddy Rev Reprod 4:23-30, 1999) play a role in spermatogenesis. © 2011 Springer Science+Business Media, LLC.

Montjean D.,ATL | Montjean D.,Institute Pasteur Paris | Montjean D.,University Paris - Sud | Menezo Y.,Laboratoire dEylau | And 5 more authors.
Zygote | Year: 2010

Summary Malondialdehyde (MDA), a product involved in membrane lipid peroxidation, was dosed in the sperm of 163 patients who had consulted the clinic regarding hypofertility. We attempted to determine if there was correlation between MDA content, sperm World Health Organization parameters and DNA fragmentation that results mainly from reactive oxygen species assaults. We found that no correlation could be established; however MDA and sperm decondensation were shown to be significantly linked. The impact of membrane polyunsaturated fatty acids and the role of phospholipid hydroperoxide glutathione peroxidase are discussed. Copyright © 2010 Cambridge University Press.

Menezo Y.,Laboratoire Dynabio | Menezo Y.,Laboratoire dEylau | Menezo Y.,Collège de France | Entezami F.,Laboratoire Dynabio | And 5 more authors.
Zygote | Year: 2014

One of the most important concerns in assisted reproduction (ART), and in particular ICSI, is the quality of sperm DNA. Oxidative stress is one of the major causes of damage to DNA and attempting to reduce generation of DNA damage related to reactive oxygen species (ROS) through consumption of antioxidants is often tempting. However, current antioxidant treatments, given irrespectively of clinically quantified deficiencies, are poorly efficient, potentially detrimental and over-exposure is risky. Here we discuss new treatments in relation to present day concepts on oxidative stress. This discussion includes stimulation of endogenous anti-ROS defense i.e. glutathione synthesis and recycling of homocysteine, the epicentre of multiple ROS-linked pathologies. © 2012 Cambridge University Press.

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