Long pentraxin 3 and vitamin D receptor mRNA expression pattern of cumulus granulosa cells isolated from PCOS oocytes at different stages of nuclear maturation.

BACKGROUND: A fine-tuned pro-inflammatory and anti-inflammatory balance in the follicular unit is essential for cumulus expansion and successful ovulation. While the long pentraxin 3 (PTX3) gene is required for the expansion of cumulus cells (CCs), ovulation, resumption of meiosis and fertilization, the vitamin D receptor gene (VDR-X2) is required for intra-follicle redox balance. This study was planned to determine the expression pattern of VDR-X2 and PTX3 mRNA in CCs isolated from germinal vesicle (GV), metaphase I (MI), and metaphase II (MII) oocytes of PCOS patients with ovulatory dysfunction. METHODS: The relative expression of CC-PTX3 and CC-VDR-X2 mRNA were evaluated using qRT-PCR in a total of 79 CC samples collected from individual cumulus-oocyte complex of 40 infertile patients (20 PCOS and 20 non-PCOS normal responders) who underwent ovarian stimulation with the GnRH antagonist protocol. RESULTS: Relative PTX3 mRNA expressions of CCMI-control and CCMII-control showed 3- and 9-fold significant upregulation compared to CCGV-control, respectively. The relative PTX3 mRNA expression of CCMII-control increased approximately three fold compared to CCMI-control. Compared to CCGV-pcos, a 3-fold increase was noted in the relative PTX3 mRNA expression of CCMI-pcos and an approximately 4-fold increase in the PTX3 mRNA expression of CCMII-pcos. Relative PTX3 mRNA expression values of CCMII-pcos and CCMI-pcos were similar. A 6-fold upregulation of relative PTX3 mRNA and a 4-fold upregulation of VDR-X2 mRNA were detected in CCMII-control compared to CCMII-pcos. CC-VDR-X2 expression patterns of the PCOS and control groups overlapped with the CC-PTX3 pattern. Fertilization rates of the PCOS group exhibiting failed transcript expression were similar to normal responders. CONCLUSION: The fact that relative CC-PTX3 and CC-VDR mRNA expression does not increase during the transition from MI to MII stage in PCOS as in normal responders suggests that PTX3 and VDR expression may be defective in cumulus cells of PCOS patients with ovulatory dysfunction.

Biomechanical Forces Determine Fibroid Stem Cell Transformation and the Receptivity Status of the Endometrium: A Critical Appraisal.

Myometrium cells are an important reproductive niche in which cyclic mechanical forces of a pico-newton range are produced continuously at millisecond and second intervals. Overproduction and/or underproduction of micro-forces, due to point or epigenetic mutation, aberrant methylation, and abnormal response to hypoxia, may lead to the transformation of fibroid stem cells into fibroid-initiating stem cells. Fibroids are tumors with a high modulus of stiffness disturbing the critical homeostasis of the myometrium and they may cause unfavorable and strong mechanical forces. Micro-mechanical forces and soluble-chemical signals play a critical role in transcriptional and translational processes' maintenance, by regulating communication between the cell nucleus and its organelles. Signals coming from the external environment can stimulate cells in the format of both soluble biochemical signals and mechanical ones. The shape of the cell and the plasma membrane have a significant character in sensing electro-chemical signals, through specialized receptors and generating responses, accordingly. In order for mechanical signals to be perceived by the cell, they must be converted into biological stimuli, through a process called mechanotransduction. Transmission of fibroid-derived mechanical signals to the endometrium and their effects on receptivity modulators are mediated through a pathway known as solid-state signaling. It is not sufficiently clear which type of receptors and mechanical signals impair endometrial receptivity. However, it is known that biomechanical signals reaching the endometrium affect epithelial sodium channels, lysophosphatidic acid receptors or Rho GTPases, leading to conformational changes in endometrial proteins. Translational changes in receptivity modulators may disrupt the selectivity and receptivity functions of the endometrium, resulting in failed implantation or early pregnancy loss. By hypermethylation of the receptivity genes, micro-forces can also negatively affect decidualization and implantation. The purpose of this narrative review is to summarize the state of the art of the biomechanical forces which can determine fibroid stem cell transformation and, thus, affect the receptivity status of the endometrium with regard to fertilization and pregnancy.

Intra-ovarian stem cell transplantation in management of premature ovarian insufficiency: towards the induced Oogonial Stem Cell (iOSC).

The specialized resident-stem cells in gonads are tasked with restorating damaged ovarian cells following injury to maintain sequential reproductive events. When we talk about premature ovarian insufficiency (POI) we accept the existence of decreased stem cell and their regenerative abilities. The present study was to explain how restorating damaged ovarian cells following injury to maintain sequential reproductive events in evidence-based medicine indexed in PubMed and Web of Science. The exact mechanism is unclear stem cells transfer may improve compromised ovarian function and fertility outcome in women with POI. Soluble factors secreted by stem cell may rescue impaired mitochondrial function in oogonial stem cells, enhance metabolic capacity of resident stem cells, induce local neovascularization in the ovary, and activate gene shifting between transferred stem cells and germ cell precursors. This review may provide insight into how stem cells show some of their beneficial effects on compromised ovarian microenvironment and germ cell niche and paves the way for clinical trials for improving ovarian function of women with POI. We also had the opportunity to share our hypothesis about the design and development of induced oogonial stem cell (iOSC) and its use in POI.

Nppc/Npr2/cGMP signaling cascade maintains oocyte developmental capacity.

The follicle must fulfill the following criteria if it is to survive the period between early embryonic life and the luteinizing hormone (LH) peak. It should (i) be surrounded by pregranulosa cells; (ii) complete the first meiotic division and become dormant; and (iii) continue metabolism during the dormant stage. Interaction between the natriuretic peptide precursor type C (Nppc) and its receptor, natriuretic peptide receptor 2 (Npr2), affects female fertility through the production of oocytes with developmental capacity and maintain oocyte meiotic arrest. While Nppc is expressed in mural cells, cumulus cells express Npr2. Nppc/Npr2 system exerts its biological function on developing follicles by increasing the production of intracellular cyclic guanosine monophosphate (cGMP). This pathway not only contributes to the development of ovary and the uterus, but aids the formation of healthy eggs in terms of their morphological and genetic aspects. A defect in this pathway leads to asmall ovarian size, string-like uterine horns, and thin endometrium and myometrium. Disorganized chromosomes, abnormal cumulus expansion and early meiotic resumption occur in animals with defective Nppc/Npr2 signaling. The types and number of oocytes also decrease when there is incompetent Nppc/Npr2 signaling. This paper extends on most recent and relevant experimental evidence regarding Nppc/Npr2/cGMP signaling with regard to its crucial role in maintaining oocyte meiotic arrest and the production of oocytes with developmental capacity. We further discuss whether the agonist or antagonist forms of the members of this exciting pathway can be usedfor triggering final oocyte maturation.

Navigation problems of ICSI or naive blastocyst can be solved with artificial blastocyst.

Embryos have evolved a remarkable capacity to find implantation site. The impressive navigation ability of natural blastocysts may rely on highly sensitive signals arising from embryos and specialized signal processing strategies in the endometrium. Navigation capabilities may be compromised in ICSI embryos because of altered biochemical signaling. The design and delivery of artificial blastocyst (AB) carrying strong chemical signals may allow ICSI embryos to more easily locate to and be retained in the implantation zone. ICSI embryos will attach easily to the implantation zone after it is found by the AB. Co-transfer of the AB together with the ICSI embryo may overcome potential difficulties in implantation due to impaired embryo-maternal communication in cases with implantation failure.

Endometrial Injury Upregulates Expression of Receptivity Genes in Women with Implantation Failure.

BACKGROUND: Homeobox genes A10 (HOXA10) and A11 (HOXA11), members of the abdominal B gene family, are responsible for embryonic survival and implantation. This study was planned to investigate whether endometrial injury alters the expression of both transcripts in women with implantation failure. METHODS: A total of 54 women with implantation failure were divided into two equal groups as experimental (scratching) and sham (no scratching). Participants in the scratching group were exposed to endometrial injury in the mid-luteal phase, and those in the sham group were exposed to endometrial flushing. The scratching group, but not the sham group, underwent prior endometrial sampling. A second endometrial sampling was performed on the scratching group in the mid-luteal phase of the following cycle. The mRNA and protein levels of the HOXA10 and 11 transcripts were determined in endometrial samples collected before and after injury/flushing. Participants in each group underwent IVF/ET in the cycle after the second endometrial sampling. RESULTS: Endometrial injury caused a 60.1-fold (p < 0.01) increase in HOXA10 mRNA and a 9.0-fold increase in HOXA11 mRNA (p < 0.02). Injury resulted in a significant increase in both HOXA10 (p < 0.001) and HOXA11 protein expression (p < 0.003). There was no significant change in HOXA10 and 11 mRNA expressions after flushing. Clinical pregnancy, live birth, and miscarriage rates of the both groups were similar. CONCLUSIONS: Endometrial injury increases homeobox transcript expression at both mRNA and protein levels.

Testis spectroscopy may predict sperm retrieval rate in men with non-obstructive azoospermia undergoing micro-TESE: A pilot study

Objective: To investigate whether prior testis magnetic resonance spectroscopy predicts the success or failure of micro-dissection testicular sperm extraction (micro-TESE) in patients with non-obstructive azoospermia (NOA). Material and Methods: Nine men with NOA who were scheduled for micro-TESE for the first time, 9 NOA men with a history of previous micro-TESE and 5 fertile men were enrolled. All NOA patients and fertile controls underwent testis spectroscopy. A multi-voxel spectroscopy sequence was used. Testicular signals of choline (Cho), creatine (Cr), myo-inositol (MI), lactate, and lipids were analyzed quantitatively and compared with the results of the micro-TESEs. Results: The most prominent peaks were Cho and Cr in the fertile controls and NOA subjects with positive sperm retrieval in the micro-TESE. A high Cho peak was detected in 87% of the NOA men with positive sperm retrieval. NOA men without sperm at the previous micro-TESE showed a marked decrease in Cho and Cr signals. For positive sperm retrieval in micro-TESE, the cut-off value of Cho was 1.46 ppm, the cut-off value of Cr was 1.43 ppm, and the cut-off value of MI was 0.79 ppm. Conclusion: Testis spectroscopy can be used as a non-invasive screening method to predict the success or failure of micro-TESE.

Hypothesis: Co-transfer of genuine embryos and implantation-promoting compounds via artificial containers improve endometrium receptivity.

As with other organs endometrial functions are altered with the advancing age. Age related decrease in reproductive functions leads to decline in the number of oocytes retrieved and the synthesis of endometrial receptivity molecules. Despite the significant improvement in assisted reproductive technologies we do not have so many options to enhance endometrial receptivity. Due to lack of drugs having endometrium receptivity enhancement properties, oocyte donation seems to be the only solution for women with implantation failure. The euploid oocytes come from young and healthy donors may overcome age associated endometrial receptivity defect. Nevertheless, many reasons restrict us from using oocyte donation in women with implantation failure. We, therefore, hypothesized that by mimicking a young blastocyst's effect on endometrium, the transfer of genuine embryos and implantation-promoting compounds together might be the new treatment option for infertile women with recurrent implantation failure. Artificial beads, MI or GV oocytes, and empty zona can be used as a container for intrauterine replacement of implantation-promoting compounds.

DHEA supplementation improves endometrial HOXA-10 mRNA expression in poor responders.

OBJECTIVE: The study was planned to investigate whether DHEA supplementation had an impact on endometrial receptivity in women who were poor responders (POR). MATERIAL AND METHODS: Twenty-eight POR women who were undergoing hysteroscopy and five fertile control subjects were included. The POR women were equally subdivided into two separate groups as patients who were currently using DHEA and those who were not. Endometrial samples of the subjects were obtained during hysteroscopy at the late follicular phase. Expression levels of endometrial HOXA-10, HOXA-11, and LIF mRNA were measured with the using real-time polymerase chain reaction. Spontaneous clinical pregnancy rates were also noted. RESULTS: Compared with POR women who were not given DHEA, upregulated endometrial HOXA-10 (7.33-fold) and HOXA-11 (2.39-fold) mRNA expression were detected in POR women on DHEA. The increase in HOXA-10 mRNA was significant (p<0.03). The fold increase in HOXA-11 mRNA was found as 2.39, which indicated a positive upregulation. However, this fold increment was insignificant (p<0.45). An insignificant increase in spontaneous clinical pregnancy rates in POR women on DHEA (53.3%) was observed compared with POR women who were not given DHEA (43.8%). CONCLUSION: Oral DHEA supplementation in POR upregulates endometrial HOXA-10 mRNA expression, which is known to positively modulate endometrial receptivity.

Ghrelin action on GnRH neurons and pituitary gonadotropes might be mediated by GnIH-GPR147 system.

Acylated ghrelin (AG) effect on GnRH secretion is mediated, at least in part, by GH secreta-gogue receptor (GHS-R) which is present in the GnRH neurons. As the acylation is mandatory for binding to GHS-R, unacylated isoform of ghrelin (UAG) action on gonadotropin secretion is likely to be mediated by other receptors or mediators that have not been identified yet. UAG, therefore, may act partially via a GHS-R-independent mechanism and inhibitory impact of UAG on GnRH neurons may be executed via modulation of other neuronal networks. Ghrelin and gonadotropin inhibitory hormone (GnIH), two agonistic peptides, have been known as important regulators of reproductive events. Potential impact of ghrelin on the activity of GnIH neurons is not exactly known. Both GnIH and ghrelin are potent stimulators of food intake and inhibitors of gonadotropin release. By binding G-protein coupled GnIH receptor (GnIH-R), GPR147, which is located in the human gonadotropes and GnRh neurons, GnIH exerts an inhibitory effect on both GnRH neurons and the gonadotropes. The GnIH-GPR147 system receives information regarding the status of energy reservoir of body from circulating peptides and then transfers them to the kisspeptin-GnIH-GnRH network. Due to wide distribution of this network in brain GnIH neurons may project on ghrelin neurons in the arcuate nucleus and contribute to the regulation of UAG's central effects or vice versa. Together, the unidentified ghrelin receptor in the hypothalamus and hypophysis may be GnIH-R. Therefore, it is reasonable that ghrelin may act on both hypothalamus and hypophysis via GnIH-GPR147 system to block gonadotropin synthesis and secretion.

Great migration: epigenetic reprogramming and germ cell-oocyte metamorphosis determine individual ovarian reserve.

Emigration is defined as a synchronized movement of germ cells between the yolk sack and genital ridges. The miraculous migration of germ cells resembles the remigration of salmon traveling from one habitat to other. This migration of germ cells is indispensible for the development of new generations. It is not, however, clear why germ cells differentiate during migration but not at the place of origin. In order to escape harmful somatic signals which might disturb the proper establishment of germ cells forced germ cell migration may be necessary. Another reason may be to benefit from the opportunities of new habitats. Therefore, emigration may have powerful effects on the population dynamics of the immigrant germ cells. While some of these cells do reach their target, some others die or reach to wrong targets. Only germ cell precursors with genetically, and structurally powerful can reach their target. Likewise, epigenetic reprogramming in both migratory and post-migratory germ cells is essential for the establishment of totipotency. During this journey some germ cells may sacrifice themselves for the goodness of the others. The number and quality of germ cells reaching the genital ridge may vary depending on the problems encountered during migration. If the aim in germ cell specification is to provide an optimal ovarian reserve for the continuity of the generation, then this cascade of events cannot be only accomplished at the same level for every one but also are manifested by several outcomes. This is significant evidence supporting the possibility of unique individual ovarian reserve.