Growth differentiation factor-11 upregulates matrix metalloproteinase 2 expression by inducing Snail in human extravillous trophoblast cells

The human extravillous trophoblast (EVT) cell invasion is an important process during placentation. Although the placenta is normal tissue, the EVT cells exhibit some features common to cancer cells, including high migratory and invasive properties. Snail and Slug are transcription factors that mediate the epithelial-mesenchymal transition (EMT), a crucial event for cancer cell migration and invasion. It has been shown that GDF-11-induced matrix metalloproteinase 2 (MMP2) expression is required for EVT cell invasion. Whether GDF-11 can regulate Snail and Slug expression in human EVT cells remains unknown. If it does, the involvement of Snail and Slug in GDF-11-induced MMP2 expression and EVT cell invasion must also be defined. In the present study, using the immortalized human EVT cell line, HTR-8/SVneo, and primary cultures of human EVT cells as experimental models, our results show that GDF-11 upregulates Snail and Slug expression. ALK4 and ALK5 mediate the stimulatory effects of GDF-11 on Snail and Slug expression. In addition, we demonstrate that SMAD2 and SMAD3 are required for the GDF-11-upregulated Snail expression, while only SMAD3 is involved in GDF-11-induced Slug expression. Moreover, our results reveal that Snail mediates GDF-11-induced MMP2 expression and cell invasion but not Slug. This study increases our understanding of the biological function of GDF-11 in human EVT cells and provides a novel mechanism for regulating MMP2 and EVT cell invasion.

Development of a real-time impedance matching system for ion cyclotron resonance heating in experimental advanced superconducting tokamak

To achieve stable operation of an ion cyclotron resonance heating (ICRH) system in the Experimental Advanced Superconducting Tokamak (EAST), a real-time impedance matching system needs to be established to respond to antenna load variation during long pulse discharges. A new impedance matching method based on capacitors was proposed in this study. By considering the reflected voltage of the transmission line as the feedback parameter, the real-time impedance-matching system can quickly control the motors based on a programmable logic controller to determine the minimum reflection voltage. A real-time impedance matching system was successfully used on the test platform in the laboratory and on the ICRH system in EAST. A significant result is that we can match the variable impedance within 1 s by suitably adjusting the motor controller to ensure high-power and long-pulse operation of the ICRH system to satisfy the requirements of the EAST experiment.

Effects of hepatitis B virus infection on the treatment outcomes following in vitro fertilization/intracytoplasmic sperm injection: An analysis of 21,999 first embryo transfer cycles

To investigate the effects of hepatitis B virus (HBV) infection on the outcomes of Chinese couples undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) and the clinical data of their neonates. A total of 21,999 first embryo transfer cycles were included. They were categorized into four groups based on the couple's hepatitis B surface antigen (HBsAg) result (Group A = female HBsAg- and male HBsAg- ; Group B = female HBsAg+ and male HBsAg- ; Group C = female HBsAg- and male HBsAg+ ; Group D = female HBsAg+ and male HBsAg+ ). The fertilization rate (FR), cleavage rate (CR), implantation rate (IPR), clinical pregnancy rate (CPR), live birth rate (LBR) and miscarriage rate (MCR) were analysed. Multilevel logistic regression was applied to evaluate the association. The total prevalence of HBV infection was 5.74% (2526/43998). There were no statistically significant differences in CRs (98.69%, 98.76%, 98.66%, 98.72%, p > .05), IPRs (45.86%, 47.33%, 45.19%, 39.61%, p > .05), CPRs (62.84%, 65.05%, 61.80%, 56.81%, p > .05), MCRs (12.70%, 11.99%, 12.58%, 4%, p > .05) and LBRs (53.43%, 55.38%, 52.70%, 54.54%, p > .05) among the four groups. However, there were significant differences in FRs (66.25%, 66.55%, 66.32%, 61.92%, p < .05). Group D had the lowest FR. After adjusting for confounders, the multilevel logistic regression showed that HBsAg+ had no impact on the LBR, CPR or MCR. We also analysed the data of 14,465 newborns, including 8593 singletons and 2936 twins. Among the four groups, no variables reached statistical significance, including neonatal birth weight (NBW), twin ratio, gestational age, premature birth, delivery type, fetal macrosomia or low birth weight (p > .05). Our study demonstrates that, although biparental HBV infection may affect the FR, neither single-parent infection nor biparental HBV infection affects IVF/ICSI outcomes or neonatal outcomes.

WNK1 mediates amphiregulin-induced MMP9 expression and cell invasion in human extravillous trophoblast cells

The invasion of human extravillous trophoblast (EVT) cells is a critical event required for a successful pregnancy. Amphiregulin, a ligand of the epidermal growth factor receptor (EGFR), has been shown to stimulate cell invasion in an immortalized human EVT cell line, HTR-8/SVneo. The with-no-lysine kinase 1 (WNK1) is involved in regulating cell invasion. It is known that WNK1 is expressed in the human placenta, but its role in human EVT cells remains unknown. In the present study, we show that AREG treatment phosphorylated WNK1 at Thr60 in both HTR-8/SVneo and primary human EVT cells. The stimulatory effect of AREG on WNK1 phosphorylation was mediated by the activation of PI3K/AKT, but not the ERK1/2 signaling pathway. AREG upregulated matrix metalloproteinase 9 (MMP9) but not MMP2. In addition, cell invasiveness was increased in response to the treatment of AREG. Using the siRNA-mediated knockdown approach, our results showed that the knockdown of WNK1 attenuated the AREG-induced upregulation of MMP9 expression and cell invasion. Moreover, the expression of WNK1 was downregulated in the placentas with preeclampsia, a disease resulting from insufficiency of EVT cell invasion during pregnancy. This study discovers the physiological function of WNK1 in human EVT cells and provides important insights into the regulation of MMP9 and cell invasion in human EVT cells.

Generation of a human haploid neural stem cell line for genome-wide genetic screening

BACKGROUND

Haploid embryonic stem cells (haESCs) have been established in many species. Differentiated haploid cell line types in mammals are lacking due to spontaneous diploidization during differentiation that compromises lineage-specific screens.

AIM

To derive human haploid neural stem cells (haNSCs) to carry out lineage-specific screens.

METHODS

Human haNSCs were differentiated from human extended haESCs with the help of Y27632 (ROCK signaling pathway inhibitor) and a series of cytokines to reduce diploidization. Neuronal differentiation of haNSCs was performed to examine their neural differentiation potency. Global gene expression analysis was con-ducted to compare haNSCs with diploid NSCs and haESCs. Fluorescence activated cell sorting was performed to assess the diploidization rate of extended haESCs and haNSCs. Genetic manipulation and screening were utilized to evaluate the significance of human haNSCs as genetic screening tools.

RESULTS

Human haESCs in extended pluripotent culture medium showed more compact and smaller colonies, a higher efficiency in neural differentiation, a higher cell survival ratio and higher stability in haploidy maintenance. These characteristics effectively facilitated the derivation of human haNSCs. These human haNSCs can be generated by differentiation and maintain haploidy and multipotency to neurons and glia in the long term in vitro. After PiggyBac transfection, there were multiple insertion sites in the human haNSCs’ genome, and the insertion sites were evenly spread across all chromosomes. In addition, after the cells were treated with manganese, we were able to generate a list of manganese-induced toxicity genes, demonstrating their utility as genetic screening tools.

CONCLUSION

This is the first report of a generated human haploid somatic cell line with a complete genome, proliferative ability and neural differentiation potential that provides cell resources for recessive inheritance and drug targeted screening.

Néel Spin Currents in Antiferromagnets

Ferromagnets are known to support spin-polarized currents that control various spin-dependent transport phenomena useful for spintronics. On the contrary, fully compensated antiferromagnets are expected to support only globally spin-neutral currents. Here, we demonstrate that these globally spin-neutral currents can represent the Néel spin currents, i.e., staggered spin currents flowing through different magnetic sublattices. The Néel spin currents emerge in antiferromagnets with strong intrasublattice coupling (hopping) and drive the spin-dependent transport phenomena such as tunneling magnetoresistance (TMR) and spin-transfer torque (STT) in antiferromagnetic tunnel junctions (AFMTJs). Using RuO_{2} and Fe_{4}GeTe_{2} as representative antiferromagnets, we predict that the Néel spin currents with a strong staggered spin polarization produce a sizable fieldlike STT capable of the deterministic switching of the Néel vector in the associated AFMTJs. Our work uncovers the previously unexplored potential of fully compensated antiferromagnets and paves a new route to realize the efficient writing and reading of information for antiferromagnetic spintronics.

Betacellulin regulates gap junction intercellular communication by inducing the phosphorylation of connexin 43 in human granulosa-lutein cells

BACKGROUND

The gap junction protein, connexin 43 (Cx43) is highly expressed in human granulosa-lutein (hGL) cells. The phosphorylation of certain amino acid residues in the Cx43 protein has been shown to be related to a decline in gap junction intercellular communication (GJIC), which subsequently affects oocyte meiotic resumption. As a member of the epidermal growth factor (EGF) family, betacellulin (BTC) mediates luteinizing hormone (LH)-induced oocyte maturation and cumulus cell expansion in mammalian follicles. Whether BTC can regulate Cx43 phosphorylation, which further reduces Cx43-coupled GJIC activity in hGL cells remains to be determined.

METHODS

Immortalized human granulosa cells (SVOG cells) and primary human granulosa-lutein cells obtained from women undergoing in vitro fertilization in an academic research center were used as the study models. The expression levels of Cx43 and phosphorylated Cx43 were examined following cell incubation with BTC at different time points. Several kinase inhibitors (sotrastaurin, AG1478, and U0126) and small interfering RNAs targeting EGF receptor (EGFR) and receptor tyrosine-protein kinase 4 (ErbB4) were used to verify the specificity of the effects and to investigate the molecular mechanisms. Real-time-quantitative PCR and western blot analysis were used to detect the specific mRNA and protein levels, respectively. GJIC between SVOG cells were evaluated using a scrape loading and dye transfer assay. Results were analyzed by one-way analysis of variance.

RESULTS

The results showed that BTC induced the rapid phosphorylation of Cx43 at serine368 without altering the expression of Cx43 in primary and immortalized hGL cells. Additionally, using a dual inhibition approach (kinase inhibitors and siRNA-based expression knockdown), we demonstrated that this effect was mainly mediated by the EGFR but not the ErbB4 receptor. Furthermore, using a protein kinase C (PKC) kinase assay and a scrape-loading and dye transfer assay, we revealed that PKC signaling is the downstream signaling pathway that mediates the increase in Cx43 phosphorylation and subsequent decrease in GJIC activity in response to BTC treatment in hGL cells.

CONCLUSIONS

BTC promptly induced the phosphorylation of connexin 43 at Ser368, leading to decreased GJIC activity in hGL cells. The BTC-induced cellular activities were most likely driven by the EGFR-mediated PKC-dependent signaling pathway. Our findings shed light on the detailed molecular mechanisms by which BTC regulates the process of oocyte meiotic resumption.

TGF-β1 upregulates secreted protein acidic and rich in cysteine expression in human granulosa-lutein cells: a potential mechanism for the pathogenesis of ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a serious complication during in vitro fertilization (IVF) treatment. The upregulation of ovarian transforming growth factor-beta 1 (TGF-β1) is involved in the development of OHSS. The secreted protein acidic and rich in cysteine (SPARC) is a secreted multifunctional matricellular glycoprotein. Although the regulatory effects of TGF-β1 on SPARC expression have been reported, whether TGF-β1 regulates SPARC expression in the human ovary remains unknown. In addition, the role of SPARC in the pathogenesis of OHSS is unclear.

METHODS

A steroidogenic human ovarian granulosa-like tumor cell line, KGN, and primary culture of human granulosa-lutein (hGL) cells obtained from patients undergoing IVF treatment were used as experimental models. OHSS was induced in rats, and ovaries were collected. Follicular fluid samples were collected from 39 OHSS and 35 non-OHSS patients during oocyte retrieval. The underlying molecular mechanisms mediating the effect of TGF-β1 on SPARC expression were explored by a series of in vitro experiments.

RESULTS

TGF-β1 upregulated SPARC expression in both KGN and hGL cells. The stimulatory effect of TGF-β1 on SPARC expression was mediated by SMAD3 but not SMAD2. The transcription factors, Snail and Slug, were induced in response to the TGF-β1 treatment. However, only Slug was required for the TGF-β1-induced SPARC expression. Conversely, we found that the knockdown of SPARC decreased Slug expression. Our results also revealed that SPARC was upregulated in the OHSS rat ovaries and in the follicular fluid of OHSS patients. Knockdown of SPARC attenuated the TGF-β1-stimulated expression of vascular endothelial growth factor (VEGF) and aromatase, two markers of OHSS. Moreover, the knockdown of SPARC reduced TGF-β1 signaling by downregulating SMAD4 expression.

CONCLUSIONS

By illustrating the potential physiological and pathological roles of TGF-β1 in the regulation of SPARC in hGL cells, our results may serve to improve current strategies used to treat clinical infertility and OHSS. Video Abstract.

The role of amphiregulin in ovarian function and disease

Amphiregulin (AREG) is an epidermal growth factor (EGF)-like growth factor that binds exclusively to the EGF receptor (EGFR). Treatment with luteinizing hormone (LH) and/or human chorionic gonadotropin dramatically induces the expression of AREG in the granulosa cells of the preovulatory follicle. In addition, AREG is the most abundant EGFR ligand in human follicular fluid. Therefore, AREG is considered a predominant propagator that mediates LH surge-regulated ovarian functions in an autocrine and/or paracrine manner. In addition to the well-characterized stimulatory effect of LH on AREG expression, recent studies discovered that several local factors and epigenetic modifications participate in the regulation of ovarian AREG expression. Moreover, aberrant expression of AREG has recently been reported to contribute to the pathogenesis of several ovarian diseases, such as ovarian hyperstimulation syndrome, polycystic ovary syndrome, and epithelial ovarian cancer. Furthermore, increasing evidence has elucidated new applications of AREG in assisted reproductive technology. Collectively, these studies highlight the importance of AREG in female reproductive health and disease. Understanding the normal and pathological roles of AREG and elucidating the molecular and cellular mechanisms of AREG regulation of ovarian functions will inform innovative approaches for fertility regulation and the prevention and treatment of ovarian diseases. Therefore, this review summarizes the functional roles of AREG in ovarian function and disease.

AREG upregulates secreted protein acidic and rich in cysteine expression in human granulosa cells

The secreted protein acidic and rich in cysteine (SPARC) is a secreted glycoprotein and the expression of ovarian SPARC peaks during ovulation and luteinization. Besides, SPARC expression was induced by human chorionic gonadotropin (hCG) in rat granulosa cells. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid. AREG mediates the physiological functions of luteinizing hormone (LH)/hCG in the ovary. However, to date, the biological function of SPARC in the human ovary remains undetermined, and whether AREG regulates SPARC expression in human granulosa cells is unknown. In this study, we show that AREG upregulated SPARC expression via EGFR in a human granulosa-like tumor cell line, KGN. Treatment of AREG activated ERK1/2, JNK, p38 MAPK, and PI3K/AKT signaling pathways and all of them were required for the AREG-induced SPARC expression. Using RNA-sequencing, we identified that steroidogenic acute regulatory protein (StAR) was a downstream target gene of SPARC. In addition, we demonstrated that SPARC mRNA levels were positively correlated with the levels of StAR mRNA in the primary culture of human granulosa cells. Moreover, SPARC protein levels were positively correlated with progesterone levels in follicular fluid of in vitro fertilization patients. This study provides the regulatory role of AREG on the expression of SPARC and reveals the novel function of SPARC in progesterone production in granulosa cells.

Biomarkers identification in follicular fluid of women with OHSS by using UPLC-MS method

To figure out the differentially changed metabolites and disturbed pathways in follicular fluid (FF) of patients with OHSS in comparison to the control group undergoing in vitro fertilization (IVF), we conducted this metabolomic analysis between two groups, the OHSS group included 30 patients treated with oocyte retrieval and developed OHSS in the next 7-14 days, while another 30 patients without OHSS tendency were selected as the control group. The FF samples were obtained during the process of oocyte retrieval. FF samples were analyzed using ultra-high liquid chromatography-tandem mass spectrometry (UPLC-MS). The results identified a total of 59 differentially changed metabolites, including 33 decreased metabolites (P < 0.01) and 26 increased metabolites (P < 0.01) in FF of OHSS compared with the control group. 12 metabolites could be the most valuable biomarkers for OHSS based on ROC results. Our correlation analyses showed that deoxyinosine levels were found positively correlated with serum estradiol (E2) levels in OHSS patients, while L-isoleucine, pyruvic acid, maleamate, and arachidonic acid were found to be positively correlated with the number of retrieved oocytes. Furthermore, 4-hydroxyphenylacetaldehyde, deoxycorticosterone, creatinine, and creatine were found to be negatively associated with serum E2 levels, while 4-hydroxyphenylacetaldehyde, L-carnitine, isovaleric acid and L-2-hydroxyglutaric acid were negatively related with the number of oocytes retrieved in OHSS patients. Taken together, our study provides better identification of OHSS FF metabolic dynamics, suggesting the metabolic compounds can be used as valuable predictors or treatment targets of OHSS.

Generation of human haploid neural stem cells from parthenogenetic embryonic stem cells.. [DOI: 10.21203/rs.3.rs-2332761/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Recently, haploid embryonic stem cells (haESCs) have been established in many species and widely used in forward and reverse genetic screening. Differentiated haploid cell line types in mammals are lacking due to spontaneous diploidization during differentiation that compromises lineage-specific screens. Human embryonic stem cells are widely used in basic and preclinical research. In this work, we report that human haESCs in extended pluripotent culture medium showed more compact colonies, higher efficiency in neural differentiation, and higher stability in haploidy maintenance, which effectively facilitated the derivation of haNSCs. Human haploid neural stem cells (haNSCs) can be generated by differentiation and maintain haploidy and multipotency to neurons and glia in the long term in vitro. After PiggyBac transfection, there were multiple insertion sites in the haNSC genome and the insertion sites evenly spread across all chromosomes. This is the first human haploid somatic cell line with a complete genome, proliferative ability and neural differentiation potential, which provides cell resources for recessive inheritance and drug targeted screening.

HB-EGF upregulates StAR expression and stimulates progesterone production through ERK1/2 signaling in human granulosa-lutein cells

Background

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) belongs to the epidermal growth factor (EGF) family of growth factors. HB-EGF and its receptors, epidermal growth factor receptor (EGFR) and HER4, are expressed in the human corpus luteum. HB-EGF has been shown to regulate luteal function by preventing cell apoptosis. Steroidogenesis is the primary function of the human corpus luteum. Steroidogenic acute regulatory protein (StAR) plays a critical role in steroidogenesis. StAR expression and progesterone (P4) production in human granulosa-lutein (hGL) cells have been shown to be upregulated by a ligand of EGFR, amphiregulin. However, whether HB-EGF can achieve the same effects remains unknown.

Methods

A steroidogenic human ovarian granulosa-like tumor cell line, KGN, and primary culture of hGL cells obtained from patients undergoing in vitro fertilization treatment were used as experimental models. The underlying molecular mechanisms mediating the effects of HB-EGF on StAR expression and P4 production were explored by a series of in vitro experiments.

Results

Western blot showed that EGFR, HER2, and HER4 were expressed in both KGN and hGL cells. Treatment with HB-EGF for 24 h induced StAR expression but did not affect the expression of steroidogenesis-related enzymes, P450 side chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase, and aromatase. Using pharmacological inhibitors and a siRNA-mediated knockdown approach, we showed that EGFR, HER4, but not HER2, were required for HB-EGF-stimulated StAR expression and P4 production. In addition, HB-EGF-induced upregulations of StAR expression and P4 production were mediated by the activation of the ERK1/2 signaling pathway.

Conclusion

This study increases the understanding of the physiological role of HB-EGF in human luteal functions.

Visualization of Chiral Electronic Structure and Anomalous Optical Response in a Material with Chiral Charge Density Waves

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

Nicotinamide Riboside supplementation ameliorated postovulatory oocyte quality decline

The quality of postovulatory oocytes deteriorates over time which impacts the outcome of early embryonic development during human assisted reproductive technology (ART). We and other groups have found that nicotinamide adenine dinucleotide (NAD+), a prominent redox cofactor and enzyme substrate, decreases in both aging ovaries and oocytes. In this study, we found that the NAD+ levels decreased in the postovulatory mouse oocytes during in vitro culture and this decrease was partly prevented by nicotinamide riboside (NR) supplementation. NR treatment not only restored MII oocyte quality but also enhanced early embryonic development potential of postovulatory oocytes via alleviating mitochondrial dysfunction and maintaining normal spindle/chromosome structure. Also, treatment with NR decreased the ROS levels and reduced DNA damage and apoptosis in postovulatory oocytes. Taken together, our findings indicated that NR supplementation increases the oocyte quality and early embryonic development potential in post-ovulatory oocytes which could potentially increase the successful rate in ART.

GDF-11 promotes human trophoblast cell invasion by increasing ID2-mediated MMP2 expression

BACKGROUND

Growth differentiation factor-11 (GDF-11), also known as bone morphogenetic protein-11, belongs to the transforming growth factor-beta superfamily. GDF-11 was first identified as an important regulator during embryonic development. Increasing evidence has demonstrated that GDF-11 regulates the development of various organs and its aberrant expressions are associated with the risk of cardiovascular diseases and cancers. Extravillous trophoblast (EVT) cells invasion is a critical event for placenta development and needs to be finely regulated. However, to date, the biological function of GDF-11 in the human EVT cells remains unknown.

METHODS

HTR-8/SVneo, a human EVT cell line, and primary cultures of human EVT cells were used to examine the effect of GDF-11 on matrix metalloproteinase 2 (MMP2) expression. Matrigel-coated transwell invasion assay was used to examine cell invasiveness. A series of in vitro experiments were applied to explore the underlying mechanisms that mediate the effect of GDF-11 on MMP2 expression and cell invasion.

RESULTS

Treatment with GDF-11 stimulates MMP2 expression, in the HTR-8/SVneo and primary human EVT cells. Using a pharmacological inhibitor and siRNA-mediated knockdown approaches, our results demonstrated that the stimulatory effect of GDF-11 on MMP2 expression was mediated by the ALK4/5-SMAD2/3 signaling pathways. In addition, the expression of inhibitor of DNA-binding protein 2 (ID2) was upregulated by GDF-11 and that was required for the GDF-11-stimulated MMP2 expression and EVT cell invasion.

CONCLUSIONS

These findings discover a new biological function and underlying molecular mechanisms of GDF-11 in the regulation of human EVT cell invasion. Video Abstract.

TGF-β1 inhibits human trophoblast cell invasion by upregulating kisspeptin expression through ERK1/2 but not SMAD signaling pathway

BACKGROUND

Tightly regulation of extravillous cytotrophoblast (EVT) cell invasion is critical for the placentation and establishment of a successful pregnancy. Insufficient EVT cell invasion leads to the development of preeclampsia (PE) which is a leading cause of maternal and perinatal mortality and morbidity. Transforming growth factor-beta1 (TGF-β1) and kisspeptin are expressed in the human placenta and have been shown to inhibit EVT cell invasion. Kisspeptin is a downstream target of TGF-β1 in human breast cancer cells. However, whether kisspeptin is regulated by TGF-β1 and mediates TGF-β1-suppressed human EVT cell invasion remains unclear.

METHODS

The effect of TGF-β1 on kisspeptin expression and the underlying mechanisms were explored by a series of in vitro experiments in a human EVT cell line, HTR-8/SVneo, and primary cultures of human EVT cells. Serum levels of TGF-β1 and kisspeptin in patients with or without PE were measured by ELISA.

RESULTS

TGF-β1 upregulates kisspeptin expression in HTR-8/SVneo cells and primary cultures of human EVT cells. Using pharmacological inhibitor and siRNA, we demonstrate that the stimulatory effect of TGF-β1 on kisspeptin expression is mediated via the ALK5 receptor. Treatment with TGF-β1 activates SMAD2/3 canonical pathways as well as ERK1/2 and PI3K/AKT non-canonical pathways. However, only inhibition of ERK1/2 activation attenuates the stimulatory effect of TGF-β1 on kisspeptin expression. In addition, siRNA-mediated knockdown of kisspeptin attenuated TGF-β1-suppressed EVT cell invasion. Moreover, we report that serum levels of TGF-β1 and kisspeptin are significantly upregulated in patients with PE.

CONCLUSIONS

By illustrating the potential physiological role of TGF-β1 in the regulation of kisspeptin expression, our results may serve to improve current strategies used to treat placental diseases.

G protein-coupled estrogen receptor stimulates human trophoblast cell invasion via YAP-mediated ANGPTL4 expression

Insufficient invasion of trophoblast cells into the uterine decidua is associated with preeclampsia (PE). G protein-coupled estrogen receptor (GPER) is a membrane estrogen receptor involved in non-genomic estrogen signaling. GPER is expressed in human trophoblast cells and downregulated GPER levels are noted in PE. However, to date, the role of GPER in trophoblast cells remains largely unknown. Here, we applied RNA sequencing (RNA-seq) to HTR-8/SVneo human trophoblast cells in response to G1, an agonist of GPER, and identified angiopoietin-like 4 (ANGPTL4) as a target gene of GPER. Treatment of trophoblast cells with G1 or 17β-estradiol (E2) activated Yes-associated protein (YAP), the major downstream effector of the Hippo pathway, via GPER but in a mammalian STE20-like protein kinase 1 (MST1)-independent manner. Using pharmacological inhibitors as well as loss- and gain-of-function approaches, our results revealed that YAP activation was required for GPER-stimulated ANGPTL4 expression. Transwell invasion assays demonstrated that activation of GPER-induced ANGPTL4 promoted cell invasion. In addition, the expression levels of GPER, YAP, and ANGPTL4 were downregulated in the placenta of patients with PE. Our findings reveal a mechanism by which GPER exerts its stimulatory effect on human trophoblast cell invasion by upregulating YAP-mediated ANGPTL4 expression.

Cheng, Fan, Li et al. identified ANGPTL4 as a G1-induced target gene of GPER/YAP in HRT8 cells using RNA-seq and highlighted its importance in regulating trophoblast cell invasion. The authors also reported GPER downregulation in the placenta and lower estradiol levels in patients who developed preeclampsia.

EGF stimulates human trophoblast cell invasion by downregulating ID3-mediated KISS1 expression

Background

During pregnancy, trophoblast cell invasion needs to be finely controlled. Aberrant trophoblast cell invasion is associated with placental diseases. Epidermal growth factor (EGF) and its receptor, EGFR, are expressed in trophoblast cells. Although the pro-invasive effect of EGF on trophoblast cells has been reported, the underlying mechanism remains largely unknown.

Results

In the present study, we conducted an RNA sequencing (RNA-seq) to HTR-8/SVneo human trophoblast cells in response to EGF and identified KISS1 as a target gene of EGF. The human KISS1 gene encodes kisspeptin, also known as metastin, which can suppress tumor metastasis. Our results showed that EGF treatment downregulated KISS1 expression and secretion by activating the EGFR-mediated PI3K/AKT signaling pathway. In addition, the expression of inhibitor of DNA-binding protein 3 (ID3) was downregulated by EGF and that was required for the EGF-suppressed KISS1 expression. Functionally, transwell invasion assays demonstrated that EGF stimulated human trophoblast cell invasion by downregulating KISS1 expression. Preeclampsia (PE) is a placental disease characterized by insufficient trophoblast cell invasion. Our clinical results revealed that serum levels of EGF were downregulated while serum and placental levels of KISS1 were upregulated in PE patients.

Conclusions

This study demonstrates that downregulation of EGF can lead to poor trophoblast cell invasion by increasing KISS1 expression which subsequently contributes to the pathogenesis of PE.

Video Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12964-021-00783-2.

GDF-8 stimulates trophoblast cell invasion by inducing ALK5-SMAD2/3-mediated MMP2 expression

Matrix metalloproteinases (MMPs) play a pivotal role in the regulation of cell invasion. Placental trophoblast cell invasion is a precisely regulated event. Dysregulation of MMPs has been linked to various placental diseases. Growth differentiation factor-8 (GDF-8), also known as myostatin, is a member of the transforming growth factor-beta (TGF-β) superfamily. GDF-8 and its putative receptors are expressed in human extravillous cytotrophoblast cells (EVTs). Although the pro-invasive effect of GDF-8 in human EVT cells has been recently reported, the underlying molecular mechanism remains largely unknown. In this study, we investigate the effects of GDF-8 on the expression of the two most important MMPs, MMP2 and MMP9, in the HTR-8/SVneo human EVT cell line. Our results show that GDF-8 significantly upregulates the expression of MMP2. The expression of MMP9 is not affected by GDF-8. Using a siRNA-mediated knockdown approach, we reveal that the stimulatory effect of GDF-8 on MMP2 expression is mediated by the ALK5-SMAD2/3 signaling pathway. Additionally, the knockdown of MMP2 attenuates the GDF-8-induced cell invasiveness. These findings deepen our understanding of the biological roles of GDF-8 in the regulation of human trophoblast cell invasion.

Different expression and localization of aquaporin 7 and aquaporin 9 in granulosa cells, oocytes, and embryos of patients with polycystic ovary syndrome and the negatively correlated relationship with insulin regulation

OBJECTIVE

To investigate the expression of aquaporin 7 (AQP7) and aquaporin 9 (AQP9) in the granulosa cells of patients with polycystic ovary syndrome (PCOS) and healthy women and detect their localization in oocytes at the germinal vesicle (GV), metaphase I (MI), MII, embryo, and blastocyst stages and the in vitro response to insulin stimulation.

DESIGN

Randomized, assessor-blinded study.

SETTING

Reproductive medical center.

PATIENT(S)

A total of 40 women (aged 20-38 years) comprising 29 cases of primary infertility and 11 cases of secondary infertility, of whom 17 had an initial diagnosis of PCOS and three received a PCOS diagnosis after an infertility examination.

INTERVENTION(S)

Controlling different concentrations of insulin and different treatment times in cultures of normal human granulosa cells in vitro.

MAIN OUTCOME MEASURE(S)

Expression of AQP7 and AQP9 genes and proteins in granulosa cells detected by real-time quantitative polymerase chain reaction, and localization in oocytes at the GV, MI, MII, embryo, and blastocyst stages by Western blot, immunohistochemical, and immunofluorescence assays, and concentrations of insulin in follicular fluid by enzyme-linked immunosorbent assay.

RESULT(S)

The expression levels of the AQP7 mRNA and protein in the granulosa cells of patients with PCOS were higher than found in healthy controls. We found AQP7 protein expressed in human oocytes at GV, MI, MII, embryo, and blastocyst stages; it was mainly located in the nucleoplasm. In the PCOS group, the expression level of AQP9 mRNA and protein in granulosa cells was lower, and AQP9 protein was expressed in oocytes at the GV, MI, MII, embryo, and blastocyst stages; it was localized on the nuclear membrane. Compared with healthy women, the insulin expression in patients with PCOS was higher. In cultures of normal human granulosa cells in vitro, the expression of AQP7 and AQP9 mRNA and protein decreased with the increase in insulin concentration; expression statistically significantly decreased when the insulin concentration was 100 nmol/L, and after 6 to 24 hours of exposure the lowest expression levels were found at 12 hours.

CONCLUSION(S)

The different localization and expression of AQP7 and AQP9 between the two groups suggests that they might be involved in oocyte maturation and embryonic development through different regulatory pathways. The expression levels of AQP7 and AQP9 were negatively correlated with insulin regulation, suggesting that insulin might affect the maturation of PCOS follicles by changing AQP7 and AQP9 expression.

Epigallocatechin-3-gallate stimulates StAR expression and progesterone production in human granulosa cells through the 67-kDa laminin receptor-mediated CREB signaling pathway

Epigallocatechin-3-gallate (EGCG) is the most abundant and biologically active catechins extracted from green tea. The health benefits of EGCG have been extendedly studied. Ovarian steroidogenesis plays a pivotal role in maintaining normal reproductive function. Granulosa cells in the ovary are essential for steroid hormone production. To date, the effect of EGCG on steroidogenesis in human granulosa cells remains unclear. In the present study, we examine the physiological concentrations of EGCG on steroidogenesis in a steroidogenic human granulosa-like tumor cell line, KGN. Our results demonstrate that treatment with EGCG upregulates steroidogenic acute regulatory protein (StAR) expression and increases progesterone (P4) production. EGCG does not affect the expression levels of other steroidogenesis-related enzymes, such as P450 side-chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase, and aromatase. In addition, we identify the expression of 67-kDa laminin receptor (67LR) in KGN cells. Moreover, EGCG-induced StAR expression and P4 production require the 67LR-mediated activation of the PKA-CREB signaling pathway. These results provide a better understanding of the function of EGCG on ovarian steroidogenesis, which may lead to the development of alternative therapeutic approaches for reproductive disorders.

Amphiregulin stimulates human chorionic gonadotropin expression by inducing ERK1/2-mediated ID3 expression in trophoblast cells

INTRODUCTION

The human chorionic gonadotropin (hCG) is a dimer consisting of an α subunit and a β subunit which is encoded by the CGB gene and is unique to hCG. hCG is a hormone mainly synthesized by syncytiotrophoblast cells in the placenta, plays a critical role in stimulating progesterone production that is necessary for maintaining normal pregnancy in the early stage. Epidermal growth factor receptor (EGFR) belongs to the receptor tyrosine kinase family which has been shown to regulate various physiological and pathological events. In human chorionic villi and amniotic fluid, amphiregulin (AREG) is reported to be the most abundant EGFR ligand and can stimulate hCG expression. However, the underlying mechanism remains unknown.

METHODS

We use BeWo cells, the commonly used cell model for the hCG production of trophoblast cells, as an in vitro model. The effects of AREG on CGB expression and hCG secretion as well as the underlying mechanisms were explored by a series of in vitro experiments.

RESULTS

We show that treatment with AREG stimulates CGB expression and hCG secretion. Using pharmacological inhibitors, we show that the stimulatory effects of AREG on CGB expression and hCG secretion are mediated by the EGFR-activated ERK1/2 signaling pathways. In addition, the expression of inhibitor of DNA-binding protein 3 (ID3) is upregulated by AREG. Knockdown of ID3 attenuates the AREG-induced upregulation of CGB expression and hCG secretion.

DISCUSSION

This study provides important insights into the molecular mechanisms that mediate AREG-induced upregulation of hCG production in human trophoblast cells which may lead to the development of alternative therapeutic approaches for the treatment of placental diseases.

High GDF-8 in follicular fluid is associated with a low pregnancy rate in IVF patients with PCOS

Polycystic ovary syndrome (PCOS) is the most common cause of female infertility. Growth differentiation factor-8 (GDF-8) is expressed in the ovary and can be detected in human follicular fluid which provides an important microenvironment for maintaining physiological functions of the ovarian follicle. To date, the relationship between GDF-8 levels in follicular fluid and the risk of PCOS is completely unknown. In the present study, we show that during the process of the controlled ovarian hyperstimulation (COH), serum GDF-8 levels are higher on the day of gonadotropin administration and 14 days after embryo transfer in in vitro fertilization (IVF) patients with PCOS than they are in IVF patients without PCOS. Importantly, GDF-8 levels in follicular fluid at oocyte retrieval are also higher in PCOS patients than in non-PCOS patients. Treatment of primary human granulosa-lutein (hGL) cells with GDF-8 downregulates StAR protein expression and the inhibition is more pronounced in hGL cells from PCOS patients than it is in cells from non-PCOS patients. Importantly, high GDF-8 levels and low progesterone (P4) levels were associated with poor pregnancy outcomes in PCOS patients. Our results provide the first evidence that aberrant expression of GDF-8 in the follicular fluid of PCOS patients results in abnormal P4 expression, which leads to poor pregnancy outcomes.

High ovarian GDF-8 levels contribute to elevated estradiol production in ovarian hyperstimulation syndrome by stimulating aromatase expression

Rationale: Growth differentiation factor-8 (GDF-8), also known as myostatin, belongs to the transforming growth factor-beta (TGF-β) superfamily. GDF-8 is expressed in the ovary and regulates various ovarian functions. Ovarian hyperstimulation syndrome (OHSS) is one of the most serious disorders during in vitro fertilization treatment. Aromatase, encoded by the CYP19A1 gene, is the enzyme that catalyzes the final step in estradiol (E2) biosynthesis. It has been demonstrated that high serum E2 levels are associated with the development of OHSS. However, the effects of GDF-8 on aromatase expression and its roles in the pathogenesis of OHSS remain unclear. Methods: The effect of GDF-8 on aromatase expression and the underlying mechanisms were explored by a series of in vitro experiments in primary human granulosa-lutein (hGL) and KGN cells. Rat OHSS model and human follicular fluid samples were used to examine the roles of the GDF-8 system in the pathogenesis of OHSS. Results: We demonstrate that GDF-8 stimulates aromatase expression and E2 production in hGL and KGN cells. In addition, TGF-β type I receptor ALK5-mediated SMAD2/3 signaling is required for GDF-8-induced aromatase expression and E2 production. Using a rat OHSS model, we show that the aromatase and GDF-8 levels are upregulated in the ovaries of OHSS rats. Blocking the function of ALK5 by the administration of its inhibitor, SB431542, alleviates OHSS symptoms and the upregulation of aromatase. Clinical results reveal that the protein levels of GDF-8 are upregulated in the follicular fluid of OHSS patients. Moreover, the expression of GDF-8 is increased in hGL cells of OHSS patients. Conclusions: This study helps to elucidate the mechanisms mediating the expression of aromatase in human granulosa cells, which may lead to the development of alternative therapeutic approaches for OHSS.

Ovarian Hyperstimulation Syndrome Is Associated with a High Secondary Sex Ratio in Fresh IVF Cycles with Cleavage-Stage Embryo Transfer: Results for a Cohort Study

The sex ratio at birth is defined as the secondary sex ratio (SSR). Ovarian hyperstimulation syndrome (OHSS) is a serious and iatrogenic complication associated with controlled ovarian stimulation (COS) during assisted reproductive technology (ART) treatments. It has been hypothesized that the human SSR is partially controlled by parental hormone levels around the time of conception. Given the aberrant hormonal profiles observed in patients with OHSS, this retrospective study was designed to evaluate the impact of OHSS on the SSR. In this study, all included patients were divided into 3 groups: non-OHSS (n=2777), mild OHSS (n=644), and moderate OHSS (n=334). Our results showed that the overall SSR for the study population was 1.033. The SSR was significantly increased in patients with moderate OHSS (1.336) compared to non-OHSS patients (1.002) (p=0.048). Subgroup analyses showed that increases in the SSR in patients with moderate OHSS were observed in the IVF group (1.323 vs 1.052; p=0.043), but not in the ICSI groups (1.021 vs 0.866; p=0.732). In addition, the elevated serum estradiol (E2) and progesterone (P4) levels in OHSS patients were not associated with SSR. In this study, for the first time, we report that a high SSR is associated with OHSS in patients who received fresh IVF treatments. The increases in SSR in OHSS patients are not attributed to the high serum E2 and P4 levels. Our findings may make both ART clinicians and patients more aware of the influences of ART treatments on the SSR and allow clinicians to counsel patients more appropriately.

Ambient air pollutant exposure and in vitro fertilization treatment outcomes in Zhengzhou, China

OBJECTIVE

To study the association between ambient air pollutant exposure during the follicular phase and in vitro fertilization (IVF) outcomes.

DESIGN

A single-center retrospective analysis.

SETTING

Henan Province, China.

PATIENTS

Patients (n = 6659) living in Zhengzhou, Henan Province in central China who underwent their first IVF cycle at the First Affiliated Hospital of Zhengzhou University between 2013 and 2019 were included for analysis.

INTERVENTION

None.

MAIN OUTCOME MEASURE

The relationships between PM_2.5, PM₁₀, and AQI (Air Quality Index) with IVF outcomes during the follicular phase (period I, 85 days before oocyte retrieval; period II, gonadotrophin start to oocyte retrieval).

RESULTS

Compared with the bottom tertile, exposure to the top PM_2.5 and PM₁₀ tertiles during period I was associated with decreased clinical pregnancy (PM_2.5: adjusted odds ratio [OR], 0.838%, and 95% confidence interval [CI], 0.723 and 0.971; PM₁₀: adjusted OR, 0.818%, and 95% CI, 0.705 and 0.950), and decreased live birth rate (PM_2.5: adjusted odds ratio [OR], 0.852%, and 95% confidence interval [CI], 0.736 and 0.987; PM₁₀: adjusted OR, 0.850%, and 95% CI, 0.733 and 0.986), and exposure to the top PM_2.5 tertile during period II adversely affected clinical pregnancy and the live birth rate (adjusted OR, 0.824%, and 95% CI, 0.711 and 0.955; adjusted OR, 0.817%, and 95% CI, 0.706 and 0.945). Compared with the bottom PM₁₀ tertile, exposure to the middle PM₁₀ tertile in period II showed decreased clinical pregnancies and live births (adjusted OR, 0.844; 95% CI, 0.729 and 0.978, adjusted OR, 0.846; 95% CI, 0.731 and 0.979). The PM₁₀ level during period II of the follicular phase tend to adversely affect live birth rate, but the tendency did not reach significance (P = 0.051).

CONCLUSION

Exposure to PM_2.5 and PM₁₀ before oocyte retrieval has an adverse effect on IVF outcomes.

CAPSULE

Exposure to PM_2.5 and PM₁₀ before oocyte retrieval has an adverse effect on IVF outcomes.

Association of circulating monocyte chemoattractant protein-1 levels with polycystic ovary syndrome: A meta-analysis

PROBLEM

Polycystic ovary syndrome (PCOS) is a common hormonal disorder that has a huge impact on the human infertility. Increased levels of various circulating inflammatory cytokines have been observed in PCOS patients, which can contribute to the pathogenesis of PCOS. Monocyte chemoattractant protein-1 (MCP-1), a secretory chemokine, is a potent chemotactic factor that recruits monocytes/macrophages to inflammatory foci. Several previous studies comparing the circulating MCP-1 levels between non-PCOS and PCOS patients have yielded contradictory results. Therefore, the aim of this meta-analysis was to investigate whether circulating MCP-1 levels vary between non-PCOS and PCOS patients.

METHODS

Research articles published before November 11, 2020, were screened to identify eligible studies. Heterogeneity, sensitivity, and publication bias were analyzed using STATA software. Standardized mean difference (SMD) with a 95% confidence interval (CI) was calculated by the STATA software using a random-effects model.

RESULTS

11 studies were included in this meta-analysis involving 897 individuals: 368 non-PCOS patient and 529 PCOS patients. Our pooled meta-analysis results show that circulating MCP-1 levels were significantly higher in PCOS patients than in non-PCOS patients (SMD = 0.84, 95% CI = [0.37, 1.31], Z = 3.50, p < 0.01). However, due to the limited number of studies included in this meta-analysis, subgroup analysis determined that circulating MCP-1 levels were not significantly varied between obese non-PCOS and obese PCOS patients (SMD = 0.42, 95% CI = [-0.65, 1.49], Z = 0.77, p = 0.442) as well as between non-PCOS and PCOS patients without obesity (SMD = 2.04, 95% CI = [-0.84, 4.93], Z = 1.39, p = 0.166). In addition, circulating MCP-1 levels were also not significantly different between obese and non-obese PCOS patients (SMD = -0.04, 95% CI = [-0.68, 0.60], Z = 0.11, p = 0.909).

CONCLUSION

Our findings reveal that circulating MCP-1 levels are upregulated in women with PCOS and are associated with an increased risk of PCOS.

Melatonin alleviates heat stress-induced oxidative stress and apoptosis in human spermatozoa

Oxidative stress generates a large amount of reactive oxygen species (ROS) and affects sperm quality via damaging sperm DNA and compromising the intracellular homeostasis in human spermatozoa. In assisted reproductive technology (ART), it is substantial to prevent spermatozoa from ROS attack. The pineal hormone melatonin has the natural antioxidant capacity and can scavenge ROS. To the best of our knowledge, however, there are presently no studies investigating if melatonin can protect human spermatozoa from heat-induced oxidative damage. Herein, we induced oxidative stress in human spermatozoa with heat treatment, and determined that melatonin could protect human spermatozoa from heat-induced oxidative stress. We first confirmed that heat stress-induced oxidative stress damaged human spermatozoa by decreasing sperm motility and viability. Furthermore, the pretreatment of human spermatozoa by melatonin was able to alleviate such damage by suppressing sperm mitochondrial ROS generation, increasing mitochondrial membrane potential, reducing the formation of the lipid peroxidation product, 4-HNE, and reducing sperm DNA damage and apoptosis. Collectively, these findings suggest that melatonin is useful as a potential treatment option for male infertility caused by heat-induced oxidative stress.

[Analysis of respiratory syncytial virus detection outcomes of 973 cases with severe respiratory infection during 2016-2019, Yuhang district of Hangzhou]

This study collected nasopharyngeal swab specimens from severe respiratory infection cases in First People's Hospital of Yuhang District during 2016-2019. Real-time PCR was used to detect respiratory syncytial virus (RSV). Rate of RSV positive detection were analysised in different age groups and different months. A total of 973 nasopharyngeal swab specimens of severe respiratory infection cases were collected, and the total positive rate of nucleic acid test of RSV was 6.47%; The detection rate of nucleic acid in male is higher than that in female, with no statistical differences (P=0.023). The positive rate of nucleic acid test was negatively correlated with age. The positive rate was 15.2% in the group aged 0-1 years and 12% in the group aged 1-2 years. There are obvious seasonal differences in the prevalence of RSV, human are easier to infect RSV in spring and winter.

TGF-β1 stimulates aromatase expression and estradiol production through SMAD2 and ERK1/2 signaling pathways in human granulosa-lutein cells

Estradiol (E2), one of the main steroid hormones secreted by the ovaries, plays an important role in maintaining normal female reproductive function. Ovarian granulosa cells are the main source of E2 production because these cells express aromatase, which is encoded by the CYP19A1 gene and catalyzes the final step in E2 biosynthesis from androgens. Transforming growth factor-beta 1 (TGF-β1) and its receptors are expressed in human granulosa cells, and TGF-β1 expression can be detected in human follicular fluid. To date, TGF-β1 has been shown to regulate various ovarian functions. However, whether aromatase can be regulated by TGF-β1 in human granulosa cells has not been determined. In the present study, we demonstrate that TGF-β1 stimulates aromatase expression in primary human granulosa-lutein cells and in the human ovarian granulose-like tumor cell line, KGN. We used pharmacological inhibitors and small interfering RNA-mediated knockdown approaches to reveal that the SMAD2 and ERK1/2 signaling pathways are involved in TGF-β1-induced aromatase expression and E2 production. These results not only provide important insights into the molecular mechanisms that mediate TGF-β1-induced aromatase expression and E2 production in human granulosa cells but also increase the understanding of the normal physiological roles of TGF-β1 in the ovary.

Melatonin stimulates VEGF expression in human granulosa-lutein cells: A potential mechanism for the pathogenesis of ovarian hyperstimulation syndrome

Melatonin can be synthesized and secreted not only by the pineal gland but also by many extra-pineal tissues. It has been shown that many ovarian functions are regulated by melatonin locally. Ovarian hyperstimulation syndrome (OHSS) is a serious complication during ovulation induction of the in vitro fertilization treatment. To date, the etiology of OHSS is not fully understood. However, vascular endothelial growth factor (VEGF) is recognized as a critical mediator for the pathogenesis of OHSS. High expression of melatonin has been detected in the follicular fluid of OHSS patients. However, whether VEGF expression can be regulated by melatonin in human granulosa cells and further contributes to the pathogenesis of OHSS remain unknown. In this study, we show that melatonin stimulates VEGF expression in human granulosa-lutein (hGL) cells. Our results reveal that the MT2 receptor and activation of AKT are involved in melatonin-induced VEGF expression. Using a rat OHSS model, we report that the VEGF levels are up-regulated in the ovaries of OHSS rats. Blocking the melatonin system by administrating MT2 receptor antagonist, 4-P-PDOT, alleviates OHSS symptoms by decreasing the expression of VEGF. In addition, the expression levels of melatonin and VEGF in the follicular fluid of OHSS patients are up-regulated and positively correlated. This study demonstrates an important role for melatonin in regulating the pathogenesis of OHSS.

Association between human SHBG gene polymorphisms and risk of PCOS: a meta-analysis

Sex hormone-binding globulin (SHBG) is a plasma glycoprotein that binds androgens and oestrogens, and regulates their bioavailability to target tissues. To date, several human SHBG gene polymorphisms have been identified. Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders, and hyperandrogenism has been considered to be a hallmark of PCOS. Many studies have examined the association between SHBG gene polymorphisms and PCOS risk, but the results have been inconclusive or inconsistent. Therefore, the aim of this meta-analysis was to investigate whether SHBG gene polymorphisms are associated with risk of PCOS. Twelve studies were included, involving 4733 participants: 2271 patients with PCOS and 2462 control participants. The results revealed that SHBG polymorphism of eight or more (TAAAA)n pentanucleotide repeats (rs35785886) was associated with PCOS risk (odds ratio [OR] = 1.24, 95% confidence interval [CI] = 1.06, 1.44, Z = 2.77, P = 0.006) and low serum SHBG concentrations in women with PCOS (standardized mean difference = -0.83, 95% CI = -1.54, -0.12, Z = 2.30, P = 0.02). Other SHBG gene polymorphisms (rs6259, rs6257, rs727428 and rs1799941) were not significantly associated with either PCOS risk or serum SHBG concentrations. These findings suggest that the presence of a polymorphism of eight or more SHBG (TAAAA)_n may be a predictive factor for the risk of PCOS.

Upregulation of AREG, EGFR, and HER2 contributes to increased VEGF expression in granulosa cells of patients with OHSS†

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication in women undergoing induction of ovulation with human chorionic gonadotropin (hCG) for assisted reproductive techniques. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid and can be upregulated by luteinizing hormone (LH)/hCG. However, whether the expression levels of AREG, EGFR, and HER2 change in the granulosa cells of OHSS patients remains unknown. If it does, whether these molecules are involved in the development of OHSS requires investigation. In the present study, we showed that AREG, EGFR, and HER2 transcripts in granulosa cells as well as follicular fluid AREG proteins were elevated in OHSS patients. Increased AREG levels were associated with transcript levels and follicular content of vascular endothelial growth factor (VEGF), the marker for OHSS pathology. Treatment of cultured granulosa cells with AREG stimulated VEGF expression and secretion, with granulosa cells from OHSS patients showing more rapid and pronounced increases than the non-OHSS group. In addition, siRNA-mediated knockdown of EGFR and AREG attenuated the hCG-induced upregulation of VEGF. This study demonstrated that granulosa cell-secreted AREG plays an important role in the development of OHSS, suggesting that the EGFR/HER2-mediated signaling could be a novel drug target for the prevention and treatment of OHSS.

Human chorionic gonadotropin-induced amphiregulin stimulates aromatase expression in human granulosa-lutein cells: a mechanism for estradiol production in the luteal phase

STUDY QUESTION

Does amphiregulin (AREG), the most abundant and important epidermal growth factor receptor (EGFR) ligand in the follicular fluid, regulate aromatase expression in human granulosa-lutein (hGL) cells?

SUMMARY ANSWER

AREG mediates the hCG-induced up-regulation of aromatase expression and estradiol (E2) production in hGL cells.

WHAT IS KNOWN ALREADY

AREG expression and secretion are rapidly induced by hCG in hGL cells and mediate physiological functions of LH/hCG in the ovary. EGFR protein is expressed in follicles not only in the pre-ovulatory phase but also throughout the luteal phase of the menstrual cycle. After the LH surge, the human corpus luteum secretes high levels of E2, which regulates various luteal cell functions. Aromatase is an enzyme responsible for a key step in the biosynthesis of E2. However, whether AREG regulates aromatase expression and E2 production in hGL cells remains unexplored.

STUDY DESIGN, SIZE, DURATION

This study is an experimental study performed over a 1-year period. In vitro investigations examined the role of AREG in the regulation of aromatase expression and E2 production in primary hGL cells.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Primary hGL cells were obtained from women undergoing IVF treatment in an academic research center. Aromatase mRNA and protein levels were examined after exposure of hGL cells to recombinant human AREG, hCG or LH. The EGFR tyrosine kinase inhibitor AG1478, PI3K inhibitor LY294002 and siRNAs targeting EGFR, LH receptor, StAR and AREG were used to verify the specificity of the effects and to investigate the underlying molecular mechanisms. Reverse transcription quantitative real-time PCR (RT-qPCR) and western blot were used to measure the specific mRNA and protein levels, respectively. Follicular fluid and serum were collected from 65 infertile women during IVF treatment. Pearson's correlation analysis was performed to examine the correlation coefficient between two values.

MAIN RESULTS AND THE ROLE OF CHANCE

Treatment of hGL cells with AREG-stimulated aromatase expression and E2 production. Using pharmacological inhibitors and specific siRNAs, we revealed that AREG-stimulated aromatase expression and E2 production via EGFR-mediated activation of the protein kinase B (AKT) signaling pathway. In addition, inhibition of EGFR activity and AREG knockdown attenuated hCG-induced up-regulation of aromatase expression and E2 production. Importantly, the protein levels of AREG in the follicular fluid were positively correlated with the E2 levels in serum after 2 days of oocyte pick-up and in the follicular fluid of IVF patients.

LARGE-SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The in vitro setting of this study is a limitation that may not reflect the real intra-ovarian microenvironment. Clinical data were obtained from a small sample size.

WIDER IMPLICATIONS OF THE FINDINGS

Our results provide the first evidence that hCG-induced AREG contributes to aromatase expression and E2 production in the luteal phase of the menstrual cycle. A better understanding of the hormonal regulation of female reproductive function may help to develop new strategies for the treatment of clinical infertility.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Natural Science Foundation of China for Young Scientists (81601253), the specific fund of clinical medical research of Chinese Medical Association (16020160632) and the Foundation from the First Affiliated Hospital of Zhengzhou University for Young Scientists to Lanlan Fang. This work was also supported by an operating grant from the National Natural Science Foundation of China (81820108016) to Ying-Pu Sun. All authors declare no conflict of interest.

Nuclear receptor coactivator 6 promotes HTR-8/SVneo cell invasion and migration by activating NF-κB-mediated MMP9 transcription

Objectives

NCOA6 is a transcription coactivator; its deletion in mice results in growth retardation and lethality between 8.5 and 12.5 dpc with defects in the placenta. However, the transcription factor(s) and the mechanism(s) involved in the function of NCOA6 in placentation have not been elucidated. Here, the roles of NCOA6 in human cytotrophoblast invasion and migration were studied.

Materials and Methods

Human placenta tissues were collected from normal pregnancies and pregnancies complicated by early‐onset severe preeclampsia (sPE). Immunofluorescence, RT‐qPCR and Western blotting were used to determine NCOA6 expression. Transwell invasion/migration assays were performed to explore whether NCOA6 knockdown affected human placenta‐derived HTR‐8/SVneo cell invasion/migration. Gelatin zymography was performed to examine the change in the gelatinolytic activities of secreted MMP2 and MMP9. Luciferase reporter assays were used to explore whether NCOA6 coactivated NF‐κB‐mediated MMP9 transcription.

Results

NCOA6 is mainly expressed in the human placental trophoblast column, as well as in the EVTs. HTR‐8/SVneo cell invasion and migration were significantly attenuated after NCOA6 knockdown, and the secretion of MMP9 was decreased due to transcriptional suppression. NCOA6 was further found to coactivate NF‐κB‐mediated MMP9 transcription. Moreover, expression of NCOA6 was impaired in placentas of patients complicated by early‐onset sPE.

Conclusions

Thus, we demonstrated that NCOA6 is important for cytotrophoblast invasion/migration, at least partially, by activating NF‐κB‐mediated MMP9 transcription; the downregulation of NCOA6 may contribute to the pathogenesis of early‐onset sPE.

Temperature-Induced Lifshitz Transition and Possible Excitonic Instability in ZrSiSe

The nodal-line semimetals have attracted immense interest due to the unique electronic structures such as the linear dispersion and the vanishing density of states as the Fermi energy approaching the nodes. Here, we report temperature-dependent transport and scanning tunneling microscopy (spectroscopy) [STM(S)] measurements on nodal-line semimetal ZrSiSe. Our experimental results and theoretical analyses consistently demonstrate that the temperature induces Lifshitz transitions at 80 and 106 K in ZrSiSe, which results in the transport anomalies at the same temperatures. More strikingly, we observe a V-shaped dip structure around Fermi energy from the STS spectrum at low temperature, which can be attributed to co-effect of the spin-orbit coupling and excitonic instability. Our observations indicate the correlation interaction may play an important role in ZrSiSe, which owns the quasi-two-dimensional electronic structures.

Placensin is a glucogenic hormone secreted by human placenta

FBN1 encodes asprosin, a glucogenic hormone, following furin cleavage of the C-terminus of profibrillin 1. Based on evolutionary conservation between FBN1 and FBN2, together with conserved furin cleavage sites, we identified a peptide hormone placensin encoded by FBN2 based on its high expression in trophoblasts of human placenta. In primary and immortalized murine hepatocytes, placensin stimulates cAMP production, protein kinase A (PKA) activity, and glucose secretion, accompanied by increased expression of gluconeogenesis enzymes. In situ perfusion of liver and in vivo injection with placensin also stimulate glucose secretion. Placensin is secreted by immortalized human trophoblastic HTR-8/SVneo cells, whereas placensin treatment stimulates cAMP-PKA signaling in these cells, accompanied by increases in MMP9 transcripts and activities, thereby promoting cell invasion. In pregnant women, levels of serum placensin increase in a stage-dependent manner. During third trimester, serum placensin levels of patients with gestational diabetes mellitus are increased to a bigger extent compared to healthy pregnant women. Thus, placensin represents a placenta-derived hormone, capable of stimulating glucose secretion and trophoblast invasion.

The giant planar Hall effect and anisotropic magnetoresistance in Dirac node arcs semimetal PtSn4

Topological semimetals (TSMs) present intriguing quantum states and have attracted much attention in recent years because of exhibiting various anomalous magneto-transport phenomena. Theoretical prediction shows that some novel phenomena, such as negative magnetoresistance (MR) and the planar Hall effect (PHE), originate from the chiral anomaly in TSMs. In this work, high-field (33 T) Shubnikov-de Haas (SdH) oscillations are obtained to reveal the topology of PtSn4. Giant PHE and anisotropic magnetoresistance (AMR) are observed in Dirac node arcs of semimetal PtSn4. First, a non-zero transverse voltage can be acquired while tilting the in-plane magnetic field. Moreover, the amplitude of PHE sharply increases at T * ∼ 50 K with decreasing temperature, which is suggested to be related to the Fermi surface reconstruction observed in PtSn4. Subsequently, the field-dependent amplitudes of the PHE show an abnormal behavior around 50 K, which is thought to stem from the complex correlation between the chiral charge and electric one in PtSn4 driving the system into different coupling states due to the complicated band structure. On the other hand, the relative AMR is negative and up to -98% at 8.5 T. Our work proves that the PHE measurements are a convincing transport fingerprint feature to confirm the chiral anomaly in TSMs.

[Inhibitors of RAS Might Be a Good Choice for the Therapy of COVID-19 Pneumonia]

The novel coronavirus 2019 (COVID-19) infected patients by binding human ACE2, leading to severe pneumonia and highly mortality rate in patients. At present, there is no definite and effective treatment for COVID-19. ACE2 plays an important role in the RAS, and the imbalance between ACE/Ang II/AT1R pathway and ACE2/Ang (1-7)/Mas receptor pathway in the RAS system will lead to multi-system inflammation. Increased ACE and Ang II are poor prognostic factors for severe pneumonia. Animal studies have shown that RAS inhibitors could effectively relieve symptoms of acute severe pneumonia and respiratory failure. The binding of COVID-19 and ACE2 resulted in the exhaustion of ACE2, and then ACE2/Ang (1-7)/Mas receptor pathway was inhibited. The balance of the RAS system was broken, and this would lead to the exacerbation of acute severe pneumonia. Therefore, we speculate that ACEI and AT1R inhibitors could be used in patients with COVID-19 pneumonia under the condition of controlling blood pressure, and might reduce the pulmonary inflammatory response and mortality.

[Correlation between intestinal mucosal permeability and prognosis in patients with liver cirrhosis]

Objective: To investigate the correlation between changes in intestinal mucosal permeability and prognosis of patients with liver cirrhosis. Methods: Data of 89 cases with liver cirrhosis who were hospitalized in the Hepatology Department of Shanxi Provincial Hospital of Traditional Chinese Medicine from January 2017 to August 2017 were collected as the liver cirrhosis experimental group, and 40 healthy subjects were randomly selected as the healthy control group. JY-DLT, the Intestinal Mucosal Barrier Biochemical Index Analysis System was used to measure the levels of serum diamine oxidase (DAO), D-lactic acid, and endotoxin (ETX) in two groups to evaluate intestinal mucosal barrier function. Spearman's rank correlation test was used to evaluate the correlation between liver cirrhosis prognosis and intestinal mucosal permeability. The results of the two groups were compared by Mann-Whitney H test of two independent samples. One-way Anova was used for intergroup comparison. The pairwise comparison between groups was performed using the LSD or SNK test. Results: The level of ETX in patients with decompensated cirrhosis was significantly higher than that in the compensated phase, and the difference was statistically significant (P < 0.05). The levels of DAO, D-lactic acid and ETX in the liver cirrhosis group were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.01). The plasma levels of DAO, D-lactic acid and ETX in the Child-Pugh grade groups of patients with liver cirrhosis were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.05). The results of intergroup comparison showed that there were statistically significant differences in DAO, D-lactic acid and ETX levels between Child-Pugh grade A and grade B groups (t = -4.255, 2.527, -2.179, P < 0.05). Furthermore, there were statistically significant differences in the levels of D-lactic acid and ETX between the Child-Pugh grade A and grade C groups (t = -2.693, -4.248, P < 0.01).The plasma levels of DAO, D-lactic acid and ETX levels were positively correlated (r = 0.205, 0.372, 0.342, P < 0.01). D-lactic acid and ETX levels were positively correlated with CTP score, Forns' index, RPR index, APRI score, FIB-4 index and FibroScan score(P < 0.01). Conclusion: The three indices (plasma DAO, D-lactic acid, and ETX) can accurately detect the changes in intestinal mucosal permeability. Moreover, the higher index of intestinal mucosal permeability causes the more severe degree of liver cirrhosis and the correlation between the intestinal mucosal permeability and the prognosis score of liver cirrhosis provides a reference for a new evaluation system and new ideas for the treatment of liver cirrhosis.

[Inhibitors of RAS Might Be a Good Choice for the Therapy of COVID-19 Pneumonia]

The novel coronavirus 2019 (COVID-19) infected patients by binding human ACE2, leading to severe pneumonia and highly mortality rate in patients. At present, there is no definite and effective treatment for COVID-19. ACE2 plays an important role in the RAS, and the imbalance between ACE/Ang II/AT1R pathway and ACE2/Ang (1-7)/Mas receptor pathway in the RAS system will lead to multi-system inflammation. Increased ACE and Ang II are poor prognostic factors for severe pneumonia. Animal studies have shown that RAS inhibitors could effectively relieve symptoms of acute severe pneumonia and respiratory failure. The binding of COVID-19 and ACE2 resulted in the exhaustion of ACE2, and then ACE2/Ang (1-7)/Mas receptor pathway was inhibited. The balance of the RAS system was broken, and this would lead to the exacerbation of acute severe pneumonia. Therefore, we speculate that ACEI and AT1R inhibitors could be used in patients with COVID-19 pneumonia under the condition of controlling blood pressure, and might reduce the pulmonary inflammatory response and mortality.

Association between vascular endothelial growth factor gene polymorphisms and PCOS risk: a meta-analysis

Vascular endothelial growth factor (VEGF) plays important roles in the pathogenesis of polycystic ovary syndrome (PCOS). Several single nucleotide polymorphisms (SNP) of the VEGF gene have been identified and are associated with the aberrant secretion of VEGF protein. This meta-analysis aimed to evaluate the impact of the VEGF +405G>C (rs2010963), -460C>T (rs833061) and -2578A>C (rs699947) polymorphisms on PCOS susceptibility. A systematic search of the Embase, PubMed, Web of Science and Wanfang databases was carried out to identify relevant studies published before 19 July 2019. Seven eligible studies were included in this meta-analysis involving 1100 patients with PCOS and 1141 control individuals. The pooled analysis revealed no significant association between PCOS risk and the +405G>C (rs2010963), -460C>T (rs833061) or -2578A>C (rs699947) polymorphisms in women. Subgroup analysis by ethnicity indicated that Asian women carrying the VEGF +405C allele had a lower risk of PCOS (C versus G: odds ratio [OR] 0.731, 95% confidence interval [CI] 0.544-0.982, P < 0.05, I² = 46.4%; CG versus GG: OR 0.667, 95% CI 0.469-0.948, P < 0.05, I² = 18.4%; CC versus GG: OR 0.611, 95% CI 0.390-0.958, P < 0.05, I² = 24.3%). The study demonstrates that for all women regardless of ethnicity, no significant associations between VEGF SNP and PCOS were observed; however, +405G>C (rs2010963) may protect Asian women from PCOS.

Melatonin induces progesterone production in human granulosa-lutein cells through upregulation of StAR expression

Steroidogenic acute regulatory protein (StAR) mediates the rate-limiting step in ovarian steroidogenesis and progesterone (P4) synthesis. Melatonin and its receptors are expressed in human granulosa cells, and have been shown to influence basal P4 production. However, previous studies addressing the regulation of StAR expression by melatonin and its impact on P4 secretion yielded contradictory results. Here, we demonstrate that melatonin upregulates StAR expression in primary cultures of human granulosa-lutein (hGL) cells obtained from women undergoing in vitro fertilization (IVF). Using pharmacological inhibitors, we show that the stimulatory effect of melatonin on StAR expression is mediated via both MT1 and MT2 melatonin receptors. Melatonin exposure activates the PI3K/AKT signaling pathway and its inhibition attenuates the stimulatory effect of melatonin on StAR expression. Moreover, siRNA-mediated knockdown of StAR abolishes melatonin-induced P4 production. Importantly, clinical analyses demonstrate that melatonin levels in human follicular fluid are positively correlated with P4 levels in serum. By illustrating the potential physiological role of melatonin in the regulation of StAR expression and P4 production in hGL cells, our results may serve to improve current strategies used to treat clinical infertility.

[Clinical-pathological analysis of 71 cases of dermatosis papulosa nigra of Han Chinese people]

Objective: To analyze and summarize the clinical-pathological features of dermatosis papulosa nigra of Han Chinese people. Methods: We collected 71 cases of dermatosis papulosa nigra in the Third people's Hospital of Hangzhou Affiliated to Zhejiang Chinese Medical University of Department of Dermatology from January 2010 to January 2019 which were confirmed clinically and pathologically. The clinical and histopathological data of all patients were analyzed and summarized, and relevant literature were reviewed. Results: Among the 71 patients, 51 were female and 25 were male, their average age was (44±13) years, the average age of onset was (39±14) years, and the average time of diagnosis was (65±51) months. The lesions were multiple dark brown papules with smooth surface, and mostly distributed in the chest and abdomen, 46 cases (64.8%), followed by the back and neck. The mean diameter of the lesions was (1.76±0.99) mm. Meanwhile, the initial onset of pruritus was observed in 15 patients. The pathological features of all lesions were similar to seborrheic keratosis. According to pathological classification, there were 49 (69.0%) cases of the acanthotic type, 11(15.5%) cases of the hyperkeratotic type, 6 (8.5%) cases of spiroid type, 4 (5.6%) cases of irritated type, and 1 (1.4%) case of clonal type. Epidermal pigmentation and/or dermal papillary pigmented granules were observed in 56 cases (78.9%), of which 46 cases (64.8%) had basal layer pigmentation. In addition, inflammatory cell infiltration was found in the superficial dermis of lesions of 10 patients (14.1%) with symptom of itching. Conclusion: Dermatosis papulosa nigra of Han Chinese people has some unique clinical and pathological features.

P6499Genetic screening in 109 adult Chinese patients with thoracic aortic aneurysm and dissection

Background

Thoracic aortic aneurysm and dissection (TAAD) comprises a heterogenous group of cardiovascular urgencies, which could be further categorized into syndromic and non-syndromic entities. The accurate and timely identification of culprit genetic variants is of grave importance for TAAD patients, since different genetic defects have been associated with different risks for aortic dissection, thus different thresholds for preventive aortic intervention.

Purpose

With the advent of next-generation sequencing (NGS) techniques, accumulating records of rare variants have been found in TAAD patients, while inadequate functional validation also makes it difficult to give proper counsel for individual TAAD patients. Therefore, it is necessary for us to start re-evaluating clinical applications of genetic screening strategies in specific patient populations.

Methods

From June 2016 to July 2017, genetic screening using an NGS-based panel of 18 candidate genes (FBN1, FBN2, TGFBR1, TGFBR2, TGFB2, TGFB3, SMAD3, COL1A1, COL3A1, COL5A2, COL5A1, PLOD1, ACTA2, MYH11, MYLK, PRKG1, MFAP5, and SKI) was applied in 109 adult TAAD patients from our institution. Patients with bicuspid aortic valve disease, complex congenital cardiac defect, aortic root infection, aortitis, pregnancy, and an age older than 70 years were excluded from the present study.

Results

Among 109 TAAD patients, 36 harboured an FBN1 variant, including 2 splicing site, 6 frame shift, 5 non-sense, and 23 mis-sense variants. The pathogenicity of mis-sense variants was further categorized into 10 disease-causing variants via database survey, 5 disease-causing variants via family survey, and 8 variants of uncertain significance (VUS). On the other hand, 25 patients harboured a non-FBN1 variant, including 3 established pathogenic variants on TGFBR1, TGFB2, and ACTA2 genes, as well as 22 VUS. Patients with an FBN1 variant displayed younger age, lower rate of hypertension, higher rate of aortic root aneurysm, and more frequent mitral valve prolapse, while an extreme male predominance (24/25) was observed in patients with a non-FBN1 variant.

Conclusion

In an adult Chinese TAAD cohort, disease-causing genetic variants were found in 28.4% (31/109) of patients, with FBN1 mutations still being the single leading cause of disease. The present study advocated a genetic screening strategy emphasizing the detection of FBN1 mutations in adult Chinese TAAD patients, and further studies should address the pathogenicity and clinical relevance of non-FBN1 VUS in TAAD patients.