Increased expression of integrin-linked kinase during decidualization regulates the morphological transformation of endometrial stromal cells

Enhanced ovarian FKBP51 expression is associated with ovarian aging: a molecular insight for age-related fertility in women

OBJECTIVE

To study the relationship between FK506-binding protein 51 (FKBP51) and ovarian aging and/or diminished ovarian reserve (DOR) in human ovaries by comparing FKBP51 levels in granulosa cells (GCs) and cumulus cells (CCs), collected during controlled ovarian stimulation (COS) from women of advanced reproductive age and/or with a diagnosis of DOR with that of young women with normal ovarian reserve. To explore the association between increased FKBP51 expression and human ovarian aging further, expression of FKBP51 was compared in ovarian stroma of postmenopausal vs. premenopausal women. Lastly, this relation was further queried by comparing ovarian expression of several collagen genes as markers of ovarian fibrosis in 14-month-old wild-type (Fkbp5+/+) and Fkbp5 knockout (Fkbp5-/-) mice.

DESIGN

Laboratory-based experimental study.

SUBJECTS

Samples collected included follicular fluid, CCs, GCs, and serum from group 1: young women with normal ovarian reserve (<35 years; n = 12); group 2: DOR (antimüllerian hormone <1 ng/mL; n = 10); and group 3: women of advanced age with normal ovarian reserve (>37 years; n = 8). Ovarian stromal tissues obtained from surgical specimen of post-menopausal (50-65 years; n = 6) and pre-menopausal (18-30 years; n = 6). Ovarian tissues from 14-month-old Fkbp5+/+and Fkbp5-/- mice. All the experiments were performed at an academic-affiliated assisted reproductive technology unit/laboratory.

EXPOSURE

Comparison of FKBP51 expression in GCs and CCs from women undergoing COS, ovarian stromal tissue from pre- and post-menopausal women, and ovarian tissue from aged Fkbp5+/+and Fkbp5-/- mice.

MAIN OUTCOME MEASURES

(1) Level of FKBP51 in human GCs and CCs, collected during COS by performing real-time quantitative polymerase chain reaction (qPCR). (2) Immunohistochemistry to detect FKBP51 levels and Picrosirius Red staining to detect collagen deposition in human ovarian stromal tissue. (3) Real-time qPCR to compare expression levels of several collagen genes in Fkbp5+/+ and Fkbp5-/- old mice ovaries. Serum and follicular fluid levels of transforming growth factor β1, and soluble endoglin measured by enzyme-linked immunosorbent assay.

RESULTS

Immunohistochemistry revealed that FKBP51 histologic score levels in ovarian stromal tissue were significantly higher in postmenopausal vs. premenopausal women (mean ± SEM, 160.52 ± 17.75 vs. 120.67 ± 14.33; P=.002). Stronger Picrosirius Red staining, suggestive of fibrosis, was seen in ovarian stromal tissue of postmenopausal vs. premenopausal women (54.06 ± 6.94 vs. 37.50 ± 14.29; P=.02). Analysis of qPCR revealed that (1) Col1a1, Col1a2, Col3a1 levels were significantly lower in ovaries obtained from 14-month-old Fkbp5-/- vs. Fkbp5+/+ mice; (2) FKBP5 levels significantly increased in CCs of advanced age women vs. younger women (1.71 ± 0.22 vs. 1.11 ± 0.15; P=.03); and (3) FKBP5 levels were approximately threefold higher in GCs of women with DOR vs. age-matched control (3.22 ± 1.11 vs. 1.30 ± 0.54; P=.03).

CONCLUSION

This study for the first time demonstrates expression profile of FKBP51 in human ovary and its potential role in ovarian aging. Our results indicate that the up-regulation of FKBP51 is associated with ovarian aging. Moreover, in women undergoing in vitro fertilization treatment, enhanced FKBP51 expression is seen in those with DOR or women of advanced maternal reproductive age, who have poor prognosis. Therefore, drugs targeting inhibition of FKBP51 expression and/or activity may delay ovarian aging or treat premature ovarian aging.

PAI-1 promotes human endometrial stromal decidualization via inhibiting VEGFR2/PI3K/AKT signaling pathway mediated F-actin reorganization

Decidualization of endometrial stromal cells is a prerequisite for successful embryo implantation and early pregnancy. Decidualization dysregulation results in implantation failure. In our previous study, we reported that PAI-1 is abnormally downregulated in the endometrial tissue samples of patients with recurrent implantation failure. This study will explore the dynamic expression changes of PAI-1 in the endometrium during the menstrual cycle and its molecular mechanism affecting endometrial decidualization. Our findings indicated that the abundance of PAI-1 increased in the mid-secretory phase and attached a peak in the decidual phase in the endometrium of women with regular menstrual cycles. In human endometrial stromal cells (HESCs), PAI-1 knockdown attenuated endometrial decidualization by upregulating VEGFR2/PI3K/AKT signaling pathway and impaired the F-actin reorganization. Furthermore, axitinib (a VEGFR2 inhibitor) was used to inhibit the VEGFR2 protein activity and the results suggested that it eliminated the effects of PAI-1 on PI3K/AKT signaling pathways and F-actin remodeling. In addition, the interaction between PAI-1 and KNG1 was confirmed by coimmunoprecipitation assay in HESCs. Altogether, PAI-1-KNG1 may enhance the decidualization of endometrium by inhibiting VEGFR2/PI3K/AKT signaling pathway-mediated F-actin reorganization in healthy females.

Coiled-coil domain containing 25 (CCDC25) regulates cell proliferation, migration, and invasion in clear cell renal cell carcinoma by targeting the ILK-NF-κB signaling pathway

Increasing evidence has demonstrated that the expression of coil domains containing 25 (CCDC25) in various malignancies is abnormally high. However, the potential regulatory role and mechanism of CCDC25 in the development of clear cell renal cell carcinoma (ccRCC) are still unclear. In this experiment, we combined in vitro experiments such as wound healing, CCK8, and transwell assay with in vivo experiments on tumor formation in nude mice to evaluate the effect of CCDC25 on the proliferation, migration, and invasion of renal cancer cells. In addition, we also used Western blotting and qPCR to evaluate the role of CCDC25 in activating the integrin-linked kinase (ILK)-NF-κB signaling pathway. Here, we demonstrate that compared to normal tissues and cell lines, CCDC25 is overexpressed in both human ccRCC tissues and cell lines. After CCDC25 knockdown, it has obvious inhibitory effect on the proliferation, migration, and invasion of cancer cells in vitro and in vivo. In contrast, CCDC25 overexpression promotes these effects. Additionally, we also discovered that CCDC25 interacts with ILK and coordinates the activation of the NF-κB signaling pathway downstream. Generally, our study suggests that CCDC25 plays a vital role in the development of ccRCC, which also means that it may be a potential therapeutic target for ccRCC.

Regulatory action of PGRMC1 on cyclic AMP-mediated COX2 expression in human endometrial cells

Human endometrial stromal cells (ESCs) undergo differentiation, known as decidualization, and endometrial epithelial cells mature around the embryo implantation stage. In the uterus, cyclooxygenase 2 (COX2), the rate-limiting enzyme that produces prostaglandin E2, is expressed in endometrial stromal and epithelial cells, and promotes decidualization of the former cells. Our recent study demonstrated that progesterone receptor membrane component 1 (PGRMC1) is downregulated during decidualization and may be involved in cellular senescence associated with decidualization via the transcription factor forkhead box protein O1 (FOXO1). Therefore, we investigated the role of PGRMC1 in COX2 expression during differentiation and maturation of endometrial stromal and epithelial cells. Inhibition or knockdown of PGRMC1 significantly enhanced differentiation stimuli-induced COX2 expression in both cell types. However, this COX2 expression was suppressed by FOXO1 knockdown or nuclear factor-kappa B (NF-κB) inhibition. Silencing of COX2 expression inhibited PGRMC1 knockdown-induced expression of decidual markers in ESCs. Thus, PGRMC1 may be linked to FOXO1- and NF-κB-mediated COX2 expression in endometrial cells. Taken together, our data suggest that downregulation of PGRMC1 expression facilitates differentiation of endometrial cells, i.e., decidualization and glandular maturation, via upregulation of COX2 expression.

Transcriptomic profiling of canine decidualization and effects of antigestagens on decidualized dog uterine stromal cells

Maternal-stroma derived decidual cells, the only cell population in the canine placenta expressing the nuclear progesterone (P4) receptor (PGR), are crucial for the maintenance of canine pregnancy. Decreased circulating progesterone (P4) levels, or blockage of PGR function with antigestagens, terminate canine pregnancy. As an in vitro model for canine decidualization, dog uterine stromal (DUS) cells can be decidualized in vitro with cAMP. The antigestagens aglepristone and mifepristone ablate the expression of decidualization markers in DUS cells (e.g., PGR, PRLR, IGF1 or PTGES). Here, the transcriptome profile of DUS cells was investigated to acquire deeper insights into decidualization-associated changes. Additionally, effects mediated by antigestagens (competitive PGR blockers) in decidualized cells were assessed. Decidualization led to the upregulation of 1841 differentially expressed genes (DEGs, P and FDR < 0.01) involved in cellular proliferation and adhesion, mesenchymal-epithelial transition, extracellular matrix organization, and vaso- and immunomodulation. The 1475 DEGs downregulated after decidualization were mostly associated with apoptosis and cell migration. In decidualized DUS cells, aglepristone modulated 1400 DEGs and mifepristone 1558 DEGs. Interestingly, around half of the identified DEGs were modulated by only one of the antigestagens. In all cases, however, PGR-blockage was mainly associated with an inversion of several decidualization-induced effects. Comparison between antigestagen-mediated effects and transcriptional changes in the canine placenta at term allowed the identification of 191 DEGs associated with diminished cell proliferation and adhesion, and vascular and immune modulation. This study emphasizes the importance of P4/PGR signaling for decidual cell function, providing new insights into the maintenance of canine pregnancy.

FKBP51 Contributes to Uterine Leiomyoma Pathogenesis by Inducing Cell Proliferation and Extracellular Matrix Deposition

The FK506-binding protein 51 (FKBP51) binds progesterone receptor (PR), glucocorticoid receptor (GR), and androgen receptor (AR) to coregulate their transcriptional activity. We evaluated FKBP51 expression and function in human leiomyoma vs. myometrial tissues and primary cultures to discover FKBP51 role(s) in the pathogenesis of leiomyomas. Quantification of in situ FKBP51 mRNA and protein levels inpaired myometrial vs. leiomyoma tissues from proliferative and secretory phases were analyzed by qPCR (n = 14), immunoblotting (n = 20), and immunohistochemistry (n = 12). Control (scramble) vs. FKBP5 siRNA-transfected leiomyoma cell cultures were assessed for proliferation, apoptosis, and mRNA levels of genes involved in cell survival and extracellular matrix (ECM) formation. Significantly higher FKBP5 mRNA levels were detected in leiomyoma vs. paired myometrium (P < 0.001). Immunoblot (P = 0.001) and immunostaining (P ≤ 0.001) confirmed increased FKBP51 levels in leiomyoma vs. paired myometrium. Compared to control siRNA transfection, FKBP5-silenced leiomyoma cell cultures displayed significantly decreased cell survival factors and reduced proliferation (P < 0.05). Moreover, qPCR analysis revealed significantly lower mRNA levels of ECM, TIPM1, and TIPM3 proteins in FKBP5-silenced leiomyoma cell cultures (P < 0.05). Increased FKBP51 expression in leiomyoma likely involves dysregulation of steroid signaling by blocking GR and PR action and promoting proliferation and ECM production. Evaluating the effect of FKBP51 inhibition in preclinical studies will clarify its significance as a potential therapeutic approach against leiomyoma.

Nuclear receptor coactivator-6 is essential for the morphological change of human uterine stromal cell decidualization via regulating actin fiber reorganization

Nuclear receptor coactivator 6 (Ncoa6), a modulator of several nuclear receptors and transcription factors, is essential for the decidualization of endometrial stromal cells in mice. However, the function of Ncoa6 in the human endometrium remains unclear. We investigated its function in the decidualization of human endometrial stromal cells (HESCs) isolated from resected uteri. Knockdown of Ncoa6 was performed using two independent small interfering RNAs. Decidualization was induced in vitro via medroxyprogesterone and cyclic adenosine monophosphate. We compared decidualized cellular morphology between the Ncoa6 knockdown cells and control cells. Messenger RNA (mRNA) sequencing was performed to determine the Ncoa6 target genes in undecidualized HESCs. We found that the knockdown of Ncoa6 caused the failure of morphological changes in decidualized HESCs compared to that in the control cells. mRNA sequencing revealed that Ncoa6 regulates the expression of genes associated with the regulation of actin fibers. Ncoa6 knockdown cells failed to reorganize actin fibers during the decidualization of HESCs. Ncoa6 was shown to play an essential role in decidualization via the appropriate regulation of actin fiber regulation in HESCs. Herein, our in vitro studies revealed a part of the mechanisms involved in endometrial decidualization. Future research is needed to investigate these mechanisms in women with implantation defects.

Integrin-linked kinase (ILK): the known vs. the unknown and perspectives

Integrin-linked kinase (ILK) is a multifunctional molecular actor in cell-matrix interactions, cell adhesion, and anchorage-dependent cell growth. It combines functions of a signal transductor and a scaffold protein through its interaction with integrins, then facilitating further protein recruitment within the ILK-PINCH-Parvin complex. ILK is involved in crucial cellular processes including proliferation, survival, differentiation, migration, invasion, and angiogenesis, which reflects on systemic changes in the kidney, heart, muscle, skin, and vascular system, also during the embryonal development. Dysfunction of ILK underlies the pathogenesis of various diseases, including the pro-oncogenic activity in tumorigenesis. ILK localizes mostly to the cell membrane and remains an important component of focal adhesion. We do know much about ILK but a lot still remains either uncovered or unclear. Although it was initially classified as a serine/threonine-protein kinase, its catalytical activity is now questioned due to structural and functional issues, leaving the exact molecular mechanism of signal transduction by ILK unsolved. While it is known that the three isoforms of ILK vary in length, the presence of crucial domains, and modification sites, most of the research tends to focus on the main isoform of this protein while the issue of functional differences of ILK2 and ILK3 still awaits clarification. The activity of ILK is regulated on the transcriptional, protein, and post-transcriptional levels. The crucial role of phosphorylation and ubiquitylation has been investigated, but the functions of the vast majority of modifications are still unknown. In the light of all those open issues, here we present an extensive literature survey covering a wide spectrum of latest findings as well as a past-to-present view on controversies regarding ILK, finishing with pointing out some open questions to be resolved by further research.

The role of fascin in carcinogenesis and embryo implantation

The cytoskeleton, with its actin bundling proteins, plays crucial roles in a host of cellular function, such as cancer metastasis, antigen presentation and trophoblast migration and invasion, as a result of cytoskeletal remodeling. A key player in cytoskeletal remodeling is fascin. Upregulation of fascin induces the transition of epithelial phenotypes to mesenchymal phenotypes through complex interaction with transcription factors. Fascin expression also regulates mitochondrial F-actin to promote oxidative phosphorylation (OXPHOS) in some cancer cells. Trophoblast cells, on the other hand, exhibit similar physiological functions, involving the upregulation of genes crucial for its migration and invasion. Owing to the similar tumor-like characteristics among cancer and trophoblats, we review recent studies on fascin in relation to cancer and trophoblast cell biology; and based on existing evidence, link fascin to the establishment of the maternal-fetal interface.

Glucose Activates Lysine-Specific Demethylase 1 through the KEAP1/p62 Pathway

Endometrial cancer incidence increases annually. Several risk factors, including high glucose intake, are associated with endometrial cancer. We investigated whether glucose affects lysine-specific demethylase 1 (LSD1) expression and the responsible molecular mechanisms. A high concentration of glucose stimulated p62 phosphorylation and increased LSD1 protein expression. Knockdown of p62 or treatment with mammalian target of rapamycin (mTOR), transforming growth factor-β activated kinase 1 (TAK1), casein kinase 1 (CK1), and protein kinase C (PKC) inhibitors abrogated glucose-regulated LSD1 expression. Unphosphorylated p62 and LSD1 formed a complex with Kelch-like ECH-associated protein 1 (KEAP1) and were degraded by the KEAP1-dependent proteasome. Phosphorylated p62 increased LSD1 protein expression by escaping the KEAP1 proteasome complex. LSD1 and KEAP1 interaction was enhanced in the presence of the nuclear factor erythroid 2-related factor 2 (NRF2) protein. LSD1 also participated in antioxidant gene regulation with NRF2. In diabetic mice, increasing LSD1and phospho-p62 expression was observed in uterine epithelial cells. Our results indicate that glucose induces p62 phosphorylation through mTOR, TAK1, CK1, and PKC kinases. Subsequently, phospho-p62 competitively interacts with KEAP1 and releases NRF2–LSD1 from the KEAP1 proteasome complex. Our findings may have public health implications for the prevention of endometrial cancer.

GPR30 Activation by 17β-Estradiol Promotes p62 Phosphorylation and Increases Estrogen Receptor α Protein Expression by Inducing Its Release from a Complex Formed with KEAP1

Estrogens can elicit rapid cellular responses via the G-protein-coupled receptor 30 (GPR30), followed by estrogen receptor α (ERα/ESR1)-mediated genomic effects. Here, we investigated whether rapid estrogen signaling via GRP30 may affect ESR1 expression, and we examined the underlying molecular mechanisms. The exposure of human endometrial cancer cells to 17β-estradiol promoted p62 phosphorylation and increased ESR1 protein expression. However, both a GPR30 antagonist and GPR30 silencing abrogated this phenomenon. GPR30 activation by 17β-estradiol elicited the SRC/EGFR/PI3K/Akt/mTOR signaling pathway. Intriguingly, unphosphorylated p62 and ESR1 were found to form an intracellular complex with the substrate adaptor protein KEAP1. Upon phosphorylation, p62 promoted ESR1 release from the complex, to increase its protein expression. Given the critical role played by p62 in autophagy, we also examined how this process affected ESR1 expression. The activation of autophagy by everolimus decreased ESR1 by promoting p62 degradation, whereas autophagy inhibition with chloroquine increased ESR1 expression. The treatment of female C57BL/6 mice with the autophagy inhibitor hydroxychloroquine—which promotes p62 expression—increased both phosphorylated p62 and ESR1 expression in uterine epithelial cells. Collectively, our results indicate that 17β-estradiol-mediated GPR30 activation elicits the SRC/EGFR/PI3K/Akt/mTOR signaling pathway and promotes p62 phosphorylation. In turn, phosphorylated p62 increased ESR1 expression by inducing its release from complexes that included KEAP1. Our findings may lead to novel pharmacological strategies aimed at decreasing ESR1 expression in estrogen-sensitive cells.

Psychological Stress and Functional Endometrial Disorders: Update of Mechanism Insights

The human endometrium plays a vital role in providing the site for embryo implantation and maintaining the normal development and survival of the embryo. Recent studies have shown that stress is a common factor for the development of unexplained reproductive disorders. The nonreceptive endometrium and disturbed early maternal-fetal interaction might lead to infertility including the repeated embryo implantation failure and recurrent spontaneous abortion, or late pregnancy complications, thereby affecting the quality of life as well as the psychological status of the affected individuals. Additionally, psychological stress might also adversely affect female reproductive health. In recent years, several basic and clinical studies have tried to investigate the harm caused by psychological stress to reproductive health, however, the mechanism is still unclear. Here, we review the relationship between psychological stress and endometrial dysfunction, and its consequent effects on female infertility to provide new insights for clinical therapeutic interventions in the future.

Micro-RNA miR-542-3p suppresses decidualization by targeting ILK pathways in human endometrial stromal cells

Decidualization of human endometrial stromal cells (HESCs) is a vital step for successful pregnancy. However, the process by which micro-RNAs (miRNAs) regulate decidualization remains elusive. Our current study was designed to identify the mechanism of miRNA miR-542-3p and its potential targets in regulating decidualization. The results showed that miR-542-3p was down-regulated in HESCs. Luciferase assay confirmed that integrin-linked kinase (ILK) is a direct target of miR-542-3p. Overexpression of miR-542-3p resulted in decreased ILK and downstream transforming growth factor β1 (TGF-β1) and SMAD family member 2 (SMAD2) expression. Additional expression of ILK attenuates the miR542-3p-induced down-regulation of TGF-β1 and SMAD2, changes properties such as suppression of proliferation and invasion, and induction of apoptosis, thereby affecting the differentiation of HESCs. Moreover, miR-542-3p overexpression caused down-regulation of the angiogenic factors vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9), and the supernatant of HESCs overexpressing miR-542-3p inhibited the formation of tubular structures in human umbilical vein endothelial cells (HUVECs), suggesting that miR-542-3p inhibits angiogenesis of HUVECs. Furthermore, in our mouse model, following injection of miR-542-3p mimic into the endometrium of mice at pregnancy day 8 (D8), we found decreased miR-542-3p expression and loss of embryo implantation sites. In conclusion, miR-542-3p can affect the process of endometrial decidualization by down-regulating ILK. The present study adds further understanding of the process and regulation of decidualization.

Catecholestradiol Activation of Adrenergic Receptors Induces Endometrial Cell Survival via p38 MAPK Signaling

CONTEXT

Enhanced levels of catecholestradiols, 2-hydroxyestradiol (2-OHE2) or 4-hydroxyestradiol (4-OHE2), are reported in endometriosis. During gestation, catecholestradiol activation of adrenergic receptors (AR) elevates estrogen receptor (ER)-independent proliferation of uterine arterial endothelial cells.

OBJECTIVE

To investigate β-AR-mediated catecholestradiol effects on human endometrial stromal cell (HESC) and epithelial cell survival in endometriosis.

DESIGN

β-AR immunostaining of eutopic and ectopic endometria (n = 9). Assays for cell viability, 5-bromo-2'-deoxyuridine proliferation, apoptosis, quantitative PCR, and estrogenicity (alkaline phosphatase activity), as well as siRNA β-AR silencing and immunoblot analyses of cultured HESCs or Ishikawa cells treated with control or 2-OHE2 or 4-OHE2 ±β-AR antagonist or ±p38 MAPK inhibitor.

SETTING

University research institution.

PATIENTS

Women with or without endometriosis.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

β-AR expression in eutopic vs ectopic endometria and regulation of HESC survival by 2-OHE2 and 4-OHE2.

RESULTS

Eutopic and ectopic endometrial stromal and epithelial cells displayed β2-AR immunoreactivity with increased staining in the functionalis vs basalis layer (P < 0.05). Both 2-OHE2 and 4-OHE2 enhanced HESC and Ishikawa cell survival (P < 0.05), an effect abrogated by β-AR antagonist propranolol, but not ER antagonist ICI182,780. 2-OHE2 or 4-OHE2 failed to induce cell survival and estrogenic activity in ADRB2-silenced HESCs and in Ishikawa cells, respectively. Although 2-OHE2 inhibited apoptosis and BAX mRNA expression, 4-OHE2 induced proliferation and decreased apoptosis (P < 0.05). Both catecholestradiols elevated phospho-p38 MAPK levels (P < 0.05), which was blocked by propranolol, and p38 MAPK inhibitor reversed catecholestradiol-enhanced HESC survival.

CONCLUSIONS

Catecholestradiols increase endometrial cell survival by an ER-independent β-AR-mediated p38 MAPK activation, suggesting that agents blocking β-AR (e.g., propranolol) or inhibiting 2-OHE2- or 4-OHE2-generating enzymes (i.e., CYP1A1/B1) could treat endometriosis.

Value of endometrial echo pattern transformation after hCG trigger in predicting IVF pregnancy outcome: a prospective cohort study

BACKGROUND

There is much value in identifying non-invasive ways of measuring endometrial receptivity, as it has the potential to improve outcomes following in vitro fertilization (IVF). It has been suggested that endometrial echogenicity on the day of hCG administration was a good marker of endometrial receptivity. In the daily practice, we notice that patients with non-homogeneous hyperechoic endometrium on the embryo transfer day usually have lower pregnancy rates. We therefore extended the research onward transformation of echo pattern after hCG trigger to analyze the relationship between endometrial echogenicity transformation and IVF outcomes.

METHODS

A total of 146 infertile women undergoing their first IVF cycle were recruited in the prospective cohort study from August 2017 through August 2018. A series of endometrial echo pattern monitoring was carried out in these patients after hCG trigger: hCG day, from 1 through 3 days after ovum pick-up (OPU + 1, OPU + 2, OPU + 3).

RESULTS

The endometrial echogenicity value was calculated as the ratio of the hyperechogenic endometrial area over the whole endometrial area. Clinical pregnancy rate and embryo implantation rate had positive relationship with echogenicity value. The ROC curve analysis of endometrial echogenicity showed the area under curve was greatest on the second day after oocyte retrieval (OPU + 1, 2, 3 were 0.738, 0.765, 0.714 respectively) versus pregnancy. Endometrial echogenicity value on OPU + 2 had a higher predictive efficiency, and the cutoff value was 76.5%. The sensitivity was 61.3% and specificity was 82.0%. When putting the cut-off at <60%, the sensitivity was 93.8% and the specificity was 23.1%.

CONCLUSIONS

The endometrial echogenicity value on OPU + 2 was recommended to evaluate endometrial receptivity. It seemed appropriate for clinicians to provide a 'freeze all' IVF cycle and transfer in a subsequent frozen-thawed embryos cycle when echogenicity value <60% on OPU + 2.

TRIAL REGISTRATION

The registration number was ChiCTR-OOC-17012214 and the registration date was August 1st, 2017.

Inhibition of TPPP3 attenuates β-catenin/NF-κB/COX-2 signaling in endometrial stromal cells and impairs decidualization

Embryo implantation and decidualization are critical events that occur during early pregnancy. Decidualization is synchronized by the crosstalk of progesterone and the cAMP signaling pathway. Previously, we confirmed the role of TPPP3 during embryo implantation in mice, but the underlying role and mechanism of TPPP3 in decidualization has not yet been understood. The current study was aimed to investigate the role of TPPP3 in decidualization in vivo and in vitro. For in vivo experiments, decidual reaction was artificially induced in the uteri of BALB/c mice. TPPP3 was found to be highly expressed during decidualization, whereas in the uteri receiving TPPP3 siRNA, decidualization was suppressed and the expression of β-catenin and decidual marker prolactin was reduced. In human endometrium, TPPP3 protein was found to be predominantly expressed in the mid-secretory phase (LH+7). In the primary culture of human endometrial stromal cells (hESCs), TPPP3 siRNA knockdown inhibited stromal-to-decidual cell transition and decreased the expression of the decidualization markers prolactin and IGFBP-1. Immunofluorescence and immunoblotting experiments revealed that TPPP3 siRNA knockdown suppressed the expression of β-catenin, NF-κB and COX-2 in hESCs during decidualization. TPPP3 inhibition also decreased NF-kB nuclear accumulation in hESCs and suppressed NF-κB transcriptional promoter activity. COX-2 expression was significantly decreased in the presence of a selective NF-kB inhibitor (QNZ) implicating that NF-kB is involved in COX-2 expression in hESCs undergoing decidualization. TUNEL assay and FACS analysis revealed that TPPP3 knockdown induced apoptosis and caused loss of mitochondrial membrane potential in hESCs. The study suggested that TPPP3 plays a significant role in decidualization and its inhibition leads to the suppression of β-catenin/NF-κB/COX-2 signaling along with the induction of mitochondria-dependent apoptosis.

Glycogen synthase kinase (GSK) 3 in pregnancy and parturition: a systematic review of literature

Introduction: Multiple factors and pathways have been reported as critical machineries for cell differentiation and survival during pregnancy; a number of them involve glycogen synthase kinase (GSK) 3a/β. Several reports on GSK3's functional role exist; however, the specific role of GSK3 in reproductive tissues and its contribution to normal or abnormal parturition are still unclear. To fill this knowledge gap, a systematic review of literature was conducted to better understand the functional role of GSK3 in various intrauterine tissues during implantation, pregnancy, and parturition.Methods: We conducted a systematic review of literature on GSK3's expression and function reported between 1980 and 2017 in reproductive tissues during pregnancy using three electronic databases (Web of Science, Medline, and ClinicalTrials.gov). Study selection, data extraction, quality assessment and analyses were performed in duplicate by two independent reviewers.Results: A total of 738 citations were identified; 80 were selected for full text evaluation and 25 were included for final review. GSK3's regulation and function were mostly studied in tissues and cells from placentas (12), fetuses (8), uteruses (6), and ovaries (2). GSK3 is primarily reported as a downstream responder of protein kinase B (AKT)-, Wnt-, and reactive oxygen species (ROS)-related pathways where it plays a critical role in cell survival and growth in reproductive tissues.Conclusions: Though GSK3 has been functionally linked to a number of biological processes in reproductive tissues, it has primarily been studied as a secondary signaler of various conserved cell signaling pathways. Lack of scientific rigor in studying GSK3's role in reproductive tissues makes this molecule's function still obscure. No studies have reported GSK3 in the cervix, and very few reports exist in myometrium and decidua. This systematic review suggests more functional and mechanistic studies focusing on GSK3 need to be conducted in reproductive biology.

Circular RNAs are abundantly expressed and upregulated during repair of the damaged endometrium by Wharton's jelly-derived mesenchymal stem cells

BACKGROUND

Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) exhibit strong and powerful potential in repairing different diseases. The expression profile of circular RNA (circRNA) provides valuable insight for regulation of the repair process and exploration of reparative effect mechanisms.

METHODS

Human endometrial stromal cells (ESCs) were cultured with mifepristone to obtain damaged ESCs, which were then cocultured with or without WJ-MSCs (cocultured group versus non-cocultured group) to observe the reparative effect upon damaged ESCs by WJ-MSCs. CircRNA microarray was performed between the two groups. Based on the transcriptomics data, the differential gene expression profiles of the two groups were analyzed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and network analysis methods. Screening of a circRNA database was performed, and the results were confirmed by quantitative polymerase chain reaction (qPCR).

RESULTS

WJ-MSCs exerted a reparative effect upon damaged ESCs in the cocultured group such as improved cell morphology, higher proliferative ability, and lower apoptosis rate. CircRNA array showed that 7757 circRNAs were differentially expressed in ESCs from the cocultured group. Mitotic cell cycle, cell cycle process, and nuclear division ranked top in the GO upregulated list of the two groups, while DNA replication and cell cycle ranked top in the KEGG pathway analysis upregulated list of the two groups. The nine most aberrantly expressed circRNAs were selected for further verification in the same cohort of samples by microarray analysis. Seven of the nine most aberrantly circRNAs were confirmed to be significantly upregulated in the cocultured group. And four of the seven circRNAs (hsa_circ_0015825, hsa-circRNA4049-38, hsa-circRNA5028-15, and hsa_circ_0111659) expression both in ESCs and WJ-MSCs tended to decrease with time by qPCR. The levels of the remaining three circRNAs (hsa-circRNA8881-21, hsa_circ_0020492 and hsa_circ_ 0026141) did not change significantly over time in either ESCs or WJ-MSCs. Moreover, we focused on hsa_circRNA_0111659 and predicted its miRNAs and targeted mRNA. The association of circRNA-miRNA-mRNA is likely to be involved in regulating the repair of endometrial damage.

CONCLUSIONS

Our results presented the abundant and upregulated circRNAs profile during repair of the damaged endometrium by WJ-MSCs and provided a novel perspective for circRNAs in the regulation of WJ-MSCs for endometrial repair.

Endothelial cell leptin receptors, leptin and interleukin-8 in the pathogenesis of preeclampsia: An in-vitro study

Objective:

Increased leptin hormone and leptin receptor may enhance the generation of proinflammatory cytokines by endothelial cells and lead to endothelial dysfunction. This study assessed the umbilical cord endothelial leptin receptor levels in preeclampsia and investigated the effect of leptin on endothelial interleukin-8 (IL-8) production.

Materials and Methods:

The association between IL-8 levels with leptin stimulation was investigated in leptin-treated human endothelial cells. Endothelial cell leptin receptor levels were evaluated using immunohistochemistry staining, and endothelial IL-8 protein expression by Western blot analysis. Data are presented as mean ± standard error of the mean (SEM). Statistical significance was analyzed using Student’s t-test or Mann-Whitney U test and one-way analysis of variance.

Results:

Leptin receptor immunoreactivity increased significantly in umbilical cord venous and arterial endothelial cells in normal pregnancy (n=12) compared with preeclampsia (n=7) endothelial cells. The corresponding preeclampsia versus control histologic scores (mean ± SEM) were 67.9±8.8 vs. 127.6±23.1, (p=0.011) for the leptin receptor and 55.4±8,0 vs. 93.7±17.1 (p=0.035), respectively, for the vein endothelial cells. Leptin treatment significantly increased IL-8 protein levels (control vs. 100 and 1000 ng/mL, p=0.003).

Conclusion:

The findings of increased umbilical cord endothelial leptin receptor levels in preeclampsia and increased endothelial IL-8 expression with exposure to higher leptin concentrations may indicate the contribution of leptin to endothelial dysfunction and increased neutrophil-endothelial interaction, which are significant pathophysiologic features of preeclampsia.