Independent regulation of matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-3 in human endometrial stromal cells by gonadotropin-releasing hormone: implications in early human implantation

Immunological Role of the Maternal Uterine Microbiome in Pregnancy: Pregnancies Pathologies and Alterated Microbiota

Understanding what happens at the time of embryo implantation has been the subject of significant research. Investigators from many differing fields including maternal fetal medicine, microbiology, genetics, reproductive endocrinology and immunology have all been studying the moment the embryo interacts with the maternal endometrium. A perfect relationship between the uterus and the embryo, mediated by a tightly controlled interaction between the embryo and the endometrium, is required for successful implantation. Any factors affecting this communication, such as altered microbiome may lead to poor reproductive outcomes. Current theories suggest that altered microbiota may trigger an inflammatory response in the endometrium that affects the success of embryo implantation, as inflammatory mediators are tightly regulated during the adhesion of the blastocyst to the epithelial endometrial wall. In this review, we will highlight the various microbiome found during the periconceptual period, the microbiomes interaction with immunological responses surrounding the time of implantation, its effect on implantation, placentation and ultimately maternal and neonatal outcomes.

Clinical pregnancy following GnRH agonist administration in the luteal phase of fresh or frozen assisted reproductive technology (ART) cycles: Systematic review and meta-analysis

Objective(s)

To study if the GnRH agonist administration in luteal phase improves clinical pregnancy rate of fresh and frozen embryo transfer. Also, this meta-analysis compares the treatment effect of luteal GnRH agonist administration between long agonist and antagonist protocols of fresh cycles, and between two types of treatment: fresh and frozen embryo transfers.

Study design

Systematic review and meta-analysis (registration number CRD42017059152)

Results

For the overall 20 studies (5497 patients), clinical pregnancy rate significantly increased in group of GnRH agonist administration compared to control group (RR 1.24, 95% CI 1.14–1.34, p < 0.0001). Regarding the treatment effect of luteal GnRH agonist administration between long agonist and antagonist protocol fresh cycles, no significant difference was observed (RR = 1.28, 95% CI 0.98–1.67, p = 0.07). Also, in comparison between fresh and frozen embryo transfer, similar effect of GnRH agonist administration was found (RR = 0.93, 95% CI 0.74–1.16, p = 0.49).

Conclusion(s)

There is evidence that GnRH agonist administration in luteal phase improve clinical pregnancy rate in both fresh and frozen cycles. Within fresh cycles, no significant difference of clinical pregnancy rate is found between two protocols. In frozen cycles, the effect of GnRH agonist administration in enhancing clinical pregnancy rate is similar to fresh cycles.

Dual trigger with gonadotropin releasing hormone agonist and human chorionic gonadotropin significantly improves live birth rate for women with diminished ovarian reserve

BACKGROUND

Diminished ovarian reserve (DOR) remains one of the greatest obstacles affecting the chance of a successful live birth after fertility treatment. The present study was set to investigate whether using a "dual trigger" consisted of human chorionic gonadotropin (hCG) plus gonadotropin releasing hormone agonist (GnRH-a) for final oocyte maturation could improve the IVF cycle outcomes for patients with diminished ovarian reserve.

METHODS

A total of 427 completed GnRH-antagonist downregulated IVF cycles with fresh embryo transfer (ET) were included in this retrospective analysis. DOR was defined as antral follicle count ≤5 and serum anti-Müllerian hormone level ≤ 1.1 ng/mL. The control group (n = 130) used a 6500 IU of recombinant hCG for trigger, and the study group (n = 297) used 0.2 mg of triptorelin plus 6500 IU of recombinant hCG for trigger.

RESULTS

The dual-trigger group had significantly higher oocyte fertilization rate (73.1% vs. 58.6%), clinical pregnancy rate (33.0% vs. 20.7%) and live birth rate (26.9% vs. 14.5%) when compared to the hCG trigger group. In addition, the abortion rate (17.4% vs. 37.0%) and embryo transfer cancellation rate (6.1% vs. 15.4%) were both significantly lower in the dual trigger group. The primary outcome measure was the live birth rate per oocyte retrieval cycle. Secondary outcome measures were embryo transfer cancellation rate, clinical pregnancy rate, implantation rate, chemical pregnancy rate and abortion rate per oocyte retrieval cycle.

CONCLUSIONS

Dual triggering the final oocyte maturation with GnRH-a and standard dose of hCG can significantly improve the live birth rate, clinical pregnancy rate, and fertilization rate in women with diminished ovarian reserve undergoing GnRH antagonist down-regulated IVF-ICSI cycles.

Anti-endometriosis Mechanism of Jiawei Foshou San Based on Network Pharmacology

Jiawei Foshou San (JFS) is the new formula originated from classic Foshou San formula, composed with ligustrazine, ferulic acid, and tetrahydropalmatine. Previously JFS inhibited the growth of endometriosis (EMS) with unclear mechanism, especially in metastasis, invasion, and epithelial-mesenchymal transition. In this study, network pharmacology was performed to explore potential mechanism of JFS on EMS. Through compound-compound target and compound target-EMS target networks, key targets were analyzed for pathway enrichment. MMP-TIMP were uncovered as one cluster of the core targets. Furthermore, autologous transplantation of EMS rat's model were used to evaluate in vivo effect of JFS on invasion, metastasis and epithelial-mesenchymal transition. JFS significantly suppressed the growth, and reduced the volume of ectopic endometrium, with modification of pathologic structure. In-depth study, invasion and metastasis were restrained after treating with JFS through decreasing MMP-2 and MMP-9, increasing TIMP-1. Meanwhile, JFS promoted E-cadherin, and attenuated N-cadherin, Vimentin, Snail, Slug, ZEB1, ZEB2, Twist. In brief, anti-EMS effect of JFS might be related to the regulation of epithelial-mesenchymal transformation, thereby inhibition of invasion and metastasis. These findings reveal the potential mechanism of JFS on EMS and the benefit for further evaluation.

Gonadotropin-releasing hormone receptor system: modulatory role in aging and neurodegeneration

Receptors for hormones of the hypothalamic-pituitary-gonadal axis are expressed throughout the brain. Age-related decline in gonadal reproductive hormones cause imbalances of this axis and many hormones in this axis have been functionally linked to neurodegenerative pathophysiology. Gonadotropin-releasing hormone (GnRH) plays a vital role in both central and peripheral reproductive regulation. GnRH has historically been known as a pituitary hormone; however, in the past few years, interest has been raised in GnRH actions at non-pituitary peripheral targets. GnRH ligands and receptors are found throughout the brain where they may act to control multiple higher functions such as learning and memory function and feeding behavior. The actions of GnRH in mammals are mediated by the activation of a unique rhodopsin-like G protein-coupled receptor that does not possess a cytoplasmic carboxyl terminal sequence. Activation of this receptor appears to mediate a wide variety of signaling mechanisms that show diversity in different tissues. Epidemiological support for a role of GnRH in central functions is evidenced by a reduction in neurodegenerative disease after GnRH agonist therapy. It has previously been considered that these effects were not via direct GnRH action in the brain, however recent data has pointed to a direct central action of these ligands outside the pituitary. We have therefore summarized the evidence supporting a central direct role of GnRH ligands and receptors in controlling central nervous physiology and pathophysiology.

Administration of single-dose GnRH agonist in the luteal phase in ICSI cycles: a meta-analysis

BACKGROUND

The effects of gonadotrophin-releasing hormone agonist (GnRH-a) administered in the luteal phase remains controversial. This meta-analysis aimed to evaluate the effect of the administration of a single-dose of GnRH-a in the luteal phase on ICSI clinical outcomes.

METHODS

The research strategy included the online search of databases. Only randomized studies were included. The outcomes analyzed were implantation rate, clinical pregnancy rate (CPR) per transfer and ongoing pregnancy rate. The fixed effects model was used for odds ratio. In all trials, a single dose of GnRH-a was administered at day 5/6 after ICSI procedures.

RESULTS

All cycles presented statistically significantly higher rates of implantation (P<0.0001), CPR per transfer (P=0.006) and ongoing pregnancy (P=0.02) in the group that received luteal-phase GnRH-a administration than in the control group (without luteal-phase-GnRH-a administration). When meta-analysis was carried out only in trials that had used long GnRH-a ovarian stimulation protocol, CPR per transfer (P=0.06) and ongoing pregnancy (P=0.23) rates were not significantly different between the groups, but implantation rate was significant higher (P=0.02) in the group that received luteal-phase-GnRH-a administration. On the other hand, the results from trials that had used GnRH antagonist multi-dose ovarian stimulation protocol showed statistically significantly higher implantation (P=0.0002), CPR per transfer (P=0.04) and ongoing pregnancy rate (P=0.04) in the luteal-phase-GnRH-a administration group. The majority of the results presented heterogeneity.

CONCLUSIONS

These findings demonstrate that the luteal-phase single-dose GnRH-a administration can increase implantation rate in all cycles and CPR per transfer and ongoing pregnancy rate in cycles with GnRH antagonist ovarian stimulation protocol. Nevertheless, by considering the heterogeneity between the trials, it seems premature to recommend the use of GnRH-a in the luteal phase. Additional randomized controlled trials are necessary before evidence-based recommendations can be provided.

Different regulation of tissue inhibitors of metalloproteinases-1, -2 and -3 in human endometrial stromal cells during decidualization in vitro

Aim:  Endometrial tissue inhibitors of metalloproteinases (TIMPs) appear to play an essential role during early implantation by modulating the invasiveness of the trophoblast. The expression of TIMP-1, TIMP-2 and TIMP-3 in human endometrial stromal cells (ESC) was investigated during decidualization in vitro. Methods:  Endometrial stromal cells were isolated from hysterectomy specimens from premenopausal women undergoing surgery for benign reasons. Decidualization in vitro was induced by the application of 1 µmol/L progesterone and 30 nmol/L 17β-estradiol over 9 days. The expression of TIMP-1, TIMP-2 and TIMP-3 in ESC was measured by semiquantitative real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay over intervals of 3 days. Results:  Decidualization in vitro was confirmed by a significant increase in prolactin expression. TIMP-1 and TIMP-2 mRNA and secreted protein showed no significant changes over the time-course of decidualization. In contrast, TIMP-3 was upregulated during the first 3 days of decidualization. An eightfold upregulation was observed until day 6, and the effect was less pronounced by day 9. Conclusion:  These results suggest a regulatory role of the TIMP system for endometrial differentiation in the second half of the menstrual cycle and in early implantation. The expression pattern of endometrial TIMP-3 might be important for the regulation of trophoblast invasion. (Reprod Med Biol 2008; 7: 169-175).

Three-dimensional ultrasound assessment of endometrial receptivity: a review

Three-dimensional ultrasound (3D US) is a new imaging modality, which is being introduced into clinical practice. Although this technique will not probably replace two-dimensional ultrasound, it is being increasingly used. It has been reported that 3D US is a very high reproducible technique. The endometrium has been paid special attention when using this technique. The aim of this paper is to address some technical aspects of 3D US and to review critically its current status in evaluating endometrial function with special focus in its role in predicting pregnancy in assisted reproductive techniques. In spontaneous cycles endometrial volume grows during follicular phase remaining constant through the luteal phase. Endometrial vascularization increases during follicular phase peaking 2-3 days before ovulation, decreasing thereafter and increasing again during mid and late luteal phase. Data from studies analysing the role of 3D US for predicting IVF outcome are controversial. An explanation for these controversial findings might be different design of reported studies, specially the timing of ultrasound evaluation.

Gonadotropin releasing hormone analogue (GnRHa) alters the expression and activation of Smad in human endometrial epithelial and stromal cells

Gonadotropin releasing hormone analogues (GnRHa) are often used to regress endometriosis implants and prevent premature luteinizing hormone surges in women undergoing controlled ovarian stimulation. In addition to GnRH central action, the expression of GnRH and receptors in the endometrium implies an autocrine/paracrine role for GnRH and an additional site of action for GnRHa. To further examine the direct action of GnRH (Leuprolide acetate) in the endometrium, we determined the effect of GnRH on endometrial stromal (ESC) and endometrial surface epithelial (HES) cells expression and activation of Smads (Smad3, -4 and -7), intracellular signals activated by transforming growth factor beta (TGF-beta), a key cytokine expressed in the endometrium. The results show that GnRH (0.1 microM) increased the expression of inhibitory Smad7 mRNA in HES with a limited effect on ESC, while moderately increasing the common Smad4 and Smad7 protein levels in these cells (P < 0.05). GnRH in a dose--(0.01 to 10 microM) and time--(5 to 30 min) dependent manner decreased the rate of Smad3 activation (phospho-Smad3, pSmad3), and altered Smad3 cellular distribution in both cell types. Pretreatment with Antide (GnRH antagonist) resulted in further suppression of Smad3 induced by GnRH, with Antide inhibition of pSmad3 in ESC. Furthermore, co-treatment of the cells with GnRH + TGF-beta, or pretreatment with TGF-beta type II receptor antisense to block TGF-beta autocrine/paracrine action, in part inhibited TGF-beta activated Smad3. In conclusion, the results indicate that GnRH acts directly on the endometrial cells altering the expression and activation of Smads, a mechanism that could lead to interruption of TGF-beta receptor signaling mediated through this pathway in the endometrium.