Dimitris Loutradis

Messenger RNA expression for the follicle-stimulating hormone receptor and luteinizing hormone receptor in human oocytes and preimplantation-stage embryos

OBJECTIVEnTo study the expression of the FSH and LH receptors in human oocytes and preimplantation embryos and their potential roles in early human development.nnnDESIGNnClinical and molecular studies.nnnSETTINGnUniversity hospital IVF center.nnnPATIENT(S)nFemale volunteers undergoing intracytoplasmic sperm injection at the IVF unit of the Athens University Hospital. All patients gave written informed consent.nnnINTERVENTION(S)nOvarian stimulation was performed with exogenous gonadotropin administration. Intracytoplasmic sperm injection was performed on mature oocytes.nnnMAIN OUTCOME MEASURE(S)nUnfertilized oocytes and zygotes and embryos at the 2-cell, 4-cell, morula, and blastocyst stage were selected for study. A polymerase chain reaction methodology was used to analyze human oocytes and embryos. Messenger RNA was reverse transcribed and amplified with FSH and LH receptor specific primers.nnnRESULT(S)nTranscripts for the FSH receptor were detected in oocytes and zygotes and embryos at the 2-cell, morula, and blastocyst stage, while no message was detected in embryos at the 4-cell stage. Transcripts for the LH receptor were observed in oocytes and zygotes and morula- and blastocyst-stage embryos, whereas no message was detected in embryos at the 2-cell and 4-cell stage.nnnCONCLUSION(S)nMessenger RNA for the FSH and LH receptors was observed in oocytes and preimplantation embryos at different stages, indicating a physiological role in the oocyte maturation process and early embryonic development in the human.

Poor responder protocols for in-vitro fertilization : options and results

Purpose of review To present the options and the results in the management of poor responders in in-vitro fertilization. Recent findings There is no controlled ovarian hyperstimulation protocol which is best suited for all poor responders. Low dose gonadotropin-releasing hormone agonist regimes appear to be most advantageous. Prediction of compromised response prior to cycle initiation by a thorough assessment of ovarian reserve as well as a careful review of past responses could allow for a more appropriate selection of a controlled ovarian hyperstimulation protocol for each individual patient. Optimistic data have been presented by the use of high doses of gonadotropins, flare up gonadotropin-releasing hormone agonist protocols (standard or microdose), stop protocols, luteal onset of gonadotropin-releasing hormone agonist, and short protocols. Natural cycle also seems to be an appropriate strategy to be considered. Summary There is no universal definition for the ‘poor responder’. Numerous strategies have been proposed to improve ovarian stimulation in poor responders, but none of them is the ideal for all such patients. More data from good quality controlled trials are needed.

REVIEW ARTICLE: Fetomaternal Immunotolerance

Implantation of mammalian conceptus in uterine cavity is the result of evolutionary adaptation, through high level of physiological procedures to ensure its success. However the majority of pregnancy losses occur before or during implantation. It is expected that exploring and defining the molecular and physiological road map during the crucial time of implantation will enable us to decode and effectively treat fertility defects. Immunological, hormonal and molecular factors participate in the feto‐maternal cross talk during implantation and designate the effectiveness of the process. The atypical expression of major histocompatibility complex and other protein‐antigens, such as Fas/FasL and petformin in human trophoblast, the modified function of cellular constituents of the feto‐maternal interface, as well as the specific role of some hormones and cytokines, represent substantive parameters of feto‐maternal immunotolerance during implantation.

Genome-wide microarray evidence that 8-cell human blastomeres over-express cell cycle drivers and under-express checkpoints

PurposeTo understand cell cycle controls in the 8-Cell human blastomere.MethodsData from whole human genome (43,377 elements) microarray analyses of RNAs from normal 8-Cell human embryos were compiled with published microarrays of RNAs from human fibroblasts, before and after induced pluripotency, and embryonic stem cells. A sub database of 3,803 genes identified by high throughput RNA knock-down studies, plus genes that oscillate in human cells, was analyzed.ResultsThirty-five genes over-detected at least 7-fold specifically on the 8-Cell arrays were enriched for cell cycle drivers and for proteins that stabilize chromosome cohesion and spindle attachment and limit DNA and centrosome replication to once per cycle.ConclusionsThese results indicate that 8-cell human blastomere cleavage is guided by cyclic over-expression of key proteins, rather than canonical checkpoints, leading to rapidly increasing gene copy number and a susceptibility to chromosome and cytokinesis mishaps, well-noted characteristics of preimplantation human embryos.

Evidence that human blastomere cleavage is under unique cell cycle control

PurposeTo understand the molecular pathways that control early human embryo development.MethodsImproved methods of linear amplification of mRNAs and whole human genome microarray analyses were utilized to characterize gene expression in normal appearing 8-Cell human embryos, in comparison with published microarrays of human fibroblasts and pluripotent stem cells.ResultsMany genes involved in circadian rhythm and cell division were over-expressed in the 8-Cells. The cell cycle checkpoints, RB and WEE1, were silent on the 8-Cell arrays, whereas the recently described tumor suppressor, UHRF2, was up-regulated >10-fold, and the proto-oncogene, MYC, and the core element of circadian rhythm, CLOCK, were elevated up to >50-fold on the 8-Cell arrays.ConclusionsThe canonical G1 and G2 cell cycle checkpoints are not active in totipotent human blastomeres, perhaps replaced by UHRF2, MYC, and intracellular circadian pathways, which may play important roles in early human development.

Pharmacogenetics in Ovarian Stimulation—Current Concepts

Ovarian response to follicle‐stimulating hormone (FSH) action differs considerably among women; this has prompted researchers to determine which factors modify this response. The challenge is to identify the genes that affect the response to FSH stimulation by the application of pharmacogenetics to assisted reproduction techniques (ARTs). Recently, new insights have been gained in the investigation of the variability in the gene that encodes the FSH receptor (FSHR) gene or genes of the estrogen pathway. Several polymorphisms of the FSHR gene have been discovered, but Ser680Asn and Thr307Ala are the two most studied. The Ser680Asn polymorphism of the FSHR gene has been found to influence the ovarian response to FSH stimulation in women undergoing in vitro fertilization (IVF), and in women with the genotype Ser/Ser, the FSHR appears to be more resistant to FSH action. The clinical implications of this finding are highly important; the ultimate goal is to apply genetic markers as routine diagnostic tests before ovarian stimulation to predict ovarian response, determine the required FSH dose, and avoid the possible complications related to FSH stimulation.

Early hCG addition to rFSH for ovarian stimulation in IVF provides better results and the cDNA copies of the hCG receptor may be an indicator of successful stimulation

A simple, safe and cost-effective treatment protocol in ovarian stimulation is of great importance in IVF practice, especially in the case of previous unsuccessful attempts. hCG has been used as a substitute of LH because of the degree of homology between the two hormones. The main aim of this prospective randomized study was to determine, for the first time, whether low dose hCG added to rFSH for ovarian stimulation could produce better results compared to the addition of rLH in women entering IVF-ET, especially in those women that had previous IVF failures. An additional aim was to find an indicator that would allow us to follow-up ovarian stimulation and, possibly, modify it in order to achieve a better IVF outcome; and that indicator may be the cDNA copies of the LH/hCG receptor. Group A patients (n = 58) were administered hCG and Group B rLH (n = 56) in addition to rFSH in the first days of ovarian stimulation. The number of follicles and oocytes and, most importantly, implantation and pregnancy rates were shown to be statistically significantly higher in the hCG group. This study has also determined, for the first time to our best knowledge, m-RNA for LH/hCG receptors in the lymphocytes of peripheral blood 40 h before ovum pick-up. cDNA levels of the hCG receptor after ovarian stimulation were significantly higher among women receiving hCG compared to those receiving LH. In addition, higher levels were encountered among women with pregnancy compared to those without, although this was not statistically significant due to the small number of pregnancies. It seems that hCG permits a highly effective and more stable occupancy of rLH/hCG receptors and gives more follicles and more oocytes. The determination of cDNA copies could be, in the future, a marker during ovulation induction protocols and of course a predictor for the outcome of ART in the special subgroup of patients with previous failures.

hCG priming effect in controlled ovarian stimulation through a long protocol.

BackgroundRecently, it has been demonstrated that, in patients down-regulated by GnRH analogues (GnRHa), a short-term pre-treatment with recombinant LH (rLH), prior to recombinant FSH (rFSH) administration, increases the number of small antral follicle prior to FSH stimulation and the yield of normally fertilized embryos. However, no data exist in the literature regarding the potential beneficial effect of hCG priming in controlled ovarian hyperstimulation (COH) through a long GnRH-a protocol, which binds the same receptor (LH/hCGR), though it is a much more potent compared to LH. The primary aims of this study were to assess the effect of short-term pre-rFSH administration of hCG in women entering an ICSI treatment cycle on follicular development, quality of oocytes and early embryo development. The secondary endpoints were to record the effects on endometrial quality and pregnancy rate.MethodsPatients with a history of at least one previous unsuccessful ICSI cycle were randomly assigned into two groups to receive treatment with either a long protocol with rFSH (control group) or a long protocol with rFSH and pre-treatment with hCG (hCG group). In particular, in the latter group, a fixed 7 days course of 200 IU/day hCG was administered as soon as pituitary desensitization was confirmed.ResultsThe mean number of oocytes retrieved was not significantly different between the two treatment groups, although the percentage of mature oocytes tended to be higher but not significantly different in hCG-treated patients. The percentage of patients with more than one grade 3 embryos was higher in the pre-treatment group, which also showed a higher pregnancy rate.ConclusionAll the above clinical observations, in conjunction with previous data, suggest a point towards a beneficial hCG priming effect in controlled ovarian hyperstimulation through a long GnRH-a down-regulation protocol, particularly in patients with previous ART failures.

Detection of RUNX2 gene expression in cumulus cells in women undergoing controlled ovarian stimulation

BackgroundRUNX2 is a transcription factor, whose expression has been recently identified in the mouse ovary. Regulation of RUNX2 expression and its function in the human ovary have not been determined yet. The aim of the present study is the investigation of the possible correlation between RUNX2 gene expression in cumulus cells and controlled ovarian stimulation and pregnancy outcomes after ART treatment.MethodsA total of 41 patients undergoing ICSI treatment for male factor infertility were enrolled into a specific ART program, during which cumulus cells were collected. The expression of RUNX2 gene in cumulus cells was examined by real-time PCR.ResultsConcerning RUNX2 gene expression, 12 out of 41 women were detected with RUNX2 expression, with ratios ranging from 0.84 to 1.00, while 28 out of 41 women had no expression (ratiou2009=u20090). Only 1 woman presented a weak RUNX2 gene expression (ratiou2009=u20090.52). From 8 women that proceeded to pregnancy, 7 of them did not express RUNX2 gene in cumulus cells, while one was the woman with weak gene expression that also achieved pregnancy. The group of women without RUNX2 expression presented higher number of follicles (pu2009=u20090.013), higher number of retrieved oocytes (pu2009=u20090.016), higher basal LH serum levels (pu2009=u20090.016) and higher peak estradiol levels (pu2009=u20090.013), while the number of fertilized oocytes differed marginally between the two groups (pu2009=u20090.089). Moreover, RUNX2 expression was negatively associated with LH levels (ORu2009=u20090.22, pu2009=u20090.021) and E2 levels (ORu2009=u20090.25, pu2009=u20090.026).ConclusionsConsequently, based on the preliminary findings of the present pilot study a potential inhibitory mechanism of RUNX2 gene is observed in the ovary when high mRNA levels are detected, suggesting that RUNX2 could possibly be used as a candidate genetic marker in the monitoring of the outcome of an ART treatment.

LH receptor gene expression in cumulus cells in women entering an ART program

PurposeLuteinizing hormone (LH) exerts its actions through its receptor (LHR), which is mainly expressed in theca cells and to a lesser extent in oocytes, granulosa and cumulus cells. The aim of the present study was the investigation of a possible correlation between LHR gene and LHR splice variants expression in cumulus cells and ovarian response as well as ART outcome.MethodsForty patients undergoing ICSI treatment for male factor infertility underwent a long luteal GnRH-agonist downregulation protocol with a fixed 5-day rLH pre-treatment prior to rFSH stimulation and samples of cumulus cells were collected on the day of egg collection. RNA extraction and cDNA preparation was followed by LHR gene expression investigation through real-time PCR. Furthermore, cumulus cells were investigated for the detection of LHR splice variants using reverse transcription PCR.ResultsConcerning LHR expression in cumulus cells, a statistically significant negative association was observed with the duration of ovarian stimulation (odds ratiou2009=u20090.23, pu2009=u20090.012). Interestingly, 6 over 7 women who fell pregnant expressed at least two specific types of LHR splice variants (735xa0bp, 621xa0bp), while only 1 out of 19 women that did not express any splice variant achieved a pregnancy.ConclusionsConsequently, the present study provide a step towards a new role of LHR gene expression profiling as a biomarker in the prediction of ovarian response at least in terms of duration of stimulation and also a tentative role of LHR splice variants expression in the prediction of pregnancy success.