Human Chorionic Gonadotropin-Stimulated Interleukin-4-Induced-1 (IL4I1) Promotes Human Decidualization via Aryl Hydrocarbon Receptor.

Decidualization is necessary for the successful establishment of early pregnancy in rodents and humans. Disturbed decidualization results in recurrent implantation failure, recurrent spontaneous abortion, and preeclampsia. Tryptophan (Trp), one of the essential amino acids in humans, has a positive effect on mammalian pregnancy. Interleukin 4-induced gene 1 (IL4I1) is a recently identified enzyme that can metabolize L-Trp to activate aryl hydrocarbon receptor (AHR). Although IDO1-catalyzed kynurenine (Kyn) from Trp has been shown to enhance human in vitro decidualization via activating AHR, whether IL4I1-catalyzed metabolites of Trp are involved in human decidualization is still unknown. In our study, human chorionic gonadotropin stimulates IL4I1 expression and secretion from human endometrial epithelial cells through ornithine decarboxylase-induced putrescine production. Either IL4I1-catalyzed indole-3-pyruvic acid (I3P) or its metabolite indole-3-aldehyde (I3A) from Trp is able to induce human in vitro decidualization by activating AHR. As a target gene of AHR, Epiregulin induced by I3P and I3A promotes human in vitro decidualization. Our study indicates that IL4I1-catalyzed metabolites from Trp can enhance human in vitro decidualization through AHR-Epiregulin pathway.

Caveolin-1 Regulation and Function in Mouse Uterus during Early Pregnancy and under Human In Vitro Decidualization.

Decidualization is essential to rodent and primate pregnancy. Senescence is increased during decidualization. Failure of senescence clearance during decidualization will cause pregnancy abnormality. Caveolin-1 is located in plasmalemmal caveolae and involved in senescence. However, whether caveolin-1 is involved in decidualization remains undefined. In this study, we examined the expression, regulation and function of Caveolin-1 during mouse early pregnancy and under mouse and human in vitro decidualization. From days 1 to 8 of pregnancy, Caveolin-1 signals are mainly located in endothelium and myometrium. Estrogen stimulates Caveolin-1 expression in endothelium. Deficiency of estrogen receptor α significantly promotes Caveolin-1 level in uterine stromal cells. Progesterone upregulates Caveolin-1 expression in luminal epithelium. During mouse in vitro decidualization, Caveolin-1 is significantly increased. However, Caveolin-1 is obviously decreased during human in vitro decidualization. Caveolin-1 overexpression and siRNA suppress and upregulate IGFBP1 expression under in vitro decidualization, respectively. Blastocysts-derived tumor necrosis factor α (TNFα) and human Chorionic Gonadotropin (hCG) regulate Caveolin-1 in mouse and human decidual cells, respectively. Caveolin-1 levels are also regulated by high glucose and insulin. In conclusion, a low level of Caveolin-1 should be beneficial for human decidualization.

Primary Cilia Restrain PI3K-AKT Signaling to Orchestrate Human Decidualization.

Endometrial decidualization plays a pivotal role during early pregnancy. Compromised decidualization has been tightly associated with recurrent implantation failure (RIF). Primary cilium is an antenna-like sensory organelle and acts as a signaling nexus to mediate Hh, Wnt, TGFß, BMP, FGF, and Notch signaling. However, whether primary cilium is involved in human decidualization is still unknown. In this study, we found that primary cilia are present in human endometrial stromal cells. The ciliogenesis and cilia length are increased by progesterone during in vitro and in vivo decidualization. Primary cilia are abnormal in the endometrium of RIF patients. Based on data from both assembly and disassembly of primary cilia, it has been determined that primary cilium is essential to human decidualization. Trichoplein (TCHP)-Aurora A signaling mediates cilia disassembly during human in vitro decidualization. Mechanistically, primary cilium modulates human decidualization through PTEN-PI3K-AKT-FOXO1 signaling. Our study highlights primary cilium as a novel decidualization-related signaling pathway.

Female reproductive abnormalities in mouse adolescent pregnancy.

There are around 300 million adolescent pregnancies worldwide, accounting for 11% of all births worldwide. Accumulating evidence demonstrates that many adverse perinatal outcomes are associated with adolescent pregnancies. However, how and why these abnormalities occur remain to be defined. In this study, pregnancy at different stages was compared between 25- and 30- day-old and mature female mice. We found that the litter size of adolescent pregnancy is significantly decreased from F1 to F3 generations compared to mature pregnancy. On days 8 and 12 of pregnancy, multiple abnormalities in decidual and placental development appear in F3 adolescent pregnancy. On days 5 and 8, uterine endoplasmic reticulum stress is dysregulated in F3 adolescent pregnancy. Embryo implantation and decidualization are also compromised in adolescent pregnancy. Many genes are abnormally expressed in adolescent estrous uteri. The abnormal endocrine environment and abnormal implantation from uterine immaturity may result in multiple pregnancy failures in adolescent pregnancy. The aim of this study is to shed light on human adolescent pregnancy.

Effects of Aurora kinase A on mouse decidualization via Stat3-plk1-cdk1 pathway.

BACKGROUND: Decidualization is essential to the successful pregnancy in mice. The molecular mechanisms and effects of Aurora kinase A (Aurora A) remain poorly understood during pregnancy. This study is the first to investigate the expression and role of Aurora A during mouse decidualization. METHODS: Quantitative real time polymerase chain reaction, western blotting and in situ hybridization were used to determine the expression of Aurora A in mouse uteri. Aurora A activity was inhibited by Aurora A inhibitor to explore the role of Aurora A on decidualization via regulating the Aurora A/Stat3/Plk1/Cdk1 signaling pathway. RESULTS: Aurora A was strongly expressed at implantation sites compared with inter-implantation sites. Furthermore, Aurora A was also significantly increased in oil-induced deciduoma compared with control. Both Aurora A mRNA and protein were significantly increased under in vitro decidualization. Under in vitro decidualization, Prl8a2, a marker of mouse decidualization, was significantly decreased by TC-S 7010, an Aurora A inhibitor. Additionally, Prl8a2 was reduced by Stat3 inhibitor, Plk1 inhibitor and Cdk1 inhibitor, respectively. Moreover, the protein levels of p-Stat3, p-Plk1 and p-Cdk1 were suppressed by TC-S 7010. The protein levels of p-Stat3, p-Plk1 and p-Cdk1 were also suppressed by S3I-201, a Stat3 inhibitor). SBE 13 HCl (Plk1 inhibitor) could reduce the protein levels of p-Plk1 and p-Cdk1. Collectively, Aurora A could regulate Stat3/Plk1/Cdk1 signaling pathway. CONCLUSION: Our study shows that Aurora A is expressed in decidual cells and should be important for mouse decidualization. Aurora A/Stat3/Plk1/Cdk1 signaling pathway may be involved in mouse decidualization.

The detrimental effects of stress-induced glucocorticoid exposure on mouse uterine receptivity and decidualization.

Glucocorticoids (GCs), stress-induced steroid hormones, are released by adrenal cortex and essential for stress adaptation. Recently, there has been renewed interest in the relationship between GCs and pregnancy following the discovery that glucocorticoid receptor is necessary for implantation. It has been widely recognized that stress is detrimental to pregnancy. However, effects of stress-induced GC exposure on uterine receptivity and decidualization are still poorly understood. This study aims to explore the effects of GCs exposure on uterine receptivity, decidualization, and their underlying mechanisms in mice. Single prolonged stress (SPS) and corticosterone (Cort) injection models were used to analyze effects of GC exposure on early pregnancy, respectively. SPS or Cort injection inhibits embryo implantation by interfering Lif signaling and stimulating the uterine deposition of collagen types I, III, and IV on day 4 of pregnancy. Uterine decidualization is also attenuated by SPS or Cort injection through suppressing Cox-2 expression. Cort-induced collagen disorder also suppresses decidualization through regulating mesenchymal-epithelial transition. Our data should shed lights for a better understanding for the effects of GCs on embryo implantation for clinical research.

Regulation and Function of Laminin A5 during Mouse and Human Decidualization.

Decidualization is essential to the establishment of pregnancy in rodents and primates. Laminin A5 (encoding by Laminin α5) is a member of the laminin family, which is mainly expressed in the basement membranes. Although laminins regulate cellular phenotype maintenance, adhesion, migration, growth, and differentiation, the expression, function, and regulation of laminin A5 during early pregnancy are still unknown. Therefore, we investigated the expression and role of laminin A5 during mouse and human decidualization. Laminin A5 is highly expressed in mouse decidua and artificially induced deciduoma. Laminin A5 is significantly increased under in vitro decidualization. Laminin A5 knockdown significantly inhibits the expression of Prl8a2, a marker for mouse decidualization. Progesterone stimulates the expression of laminin A5 in ovariectomized mouse uterus and cultured mouse stromal cells. We also show that progesterone regulates laminin A5 through the PKA-CREB-C/EBPß pathway. Laminin A5 is also highly expressed in human pregnant decidua and cultured human endometrial stromal cells during in vitro decidualization. Laminin A5 knockdown by siRNA inhibits human in vitro decidualization. Collectively, our study reveals that laminin A5 may play a pivotal role during mouse and human decidualization via the PKA-CREB-C/EBPß pathway.

Incorporating Thiourea into Fluorescent Probes: A Reliable Strategy for Mitochondrion-Targeted Imaging and Superoxide Anion Tracking in Living Cells.

Three aggregation-induced emission active fluorescent compounds, TPA-Pyr-Octane, TPA-Pyr-Br, and TPA-Pyr-Thiourea (TPA = triphenylamine pyridinium), are synthesized; their tiny differences in chemical structures result in a huge difference in cell-imaging applications. Especially, incorporating thiourea into fluorescent probes is found as a reliable strategy for mitochondrion-targeted imaging and superoxide anion tracking in living cells, which is possibly due to the presence of hydrogen bonding between thiourea and mitochondrion proteins. This finding is very useful for the design of biosensors and delivery carriers in disease treatment.

Facile Polymerization Strategy for the Construction of Eu3+-Based Fluorescent Materials with the Capability of Distinguishing D2O from H2O.

Aggregation-induced emission (AIE) and antenna effect (AE) are two important luminescence behaviors. Connecting them into polymers is a promising but challenging work, which can supply opportunities for luminescence materials with extensive applications. In this work, AIE-active Eu3+-coordinated polymers (Poly-Eu-1, -2, -3, and -4) have been synthesized, and the efficient AE was verified. This finding presents a facile approach to obtain the Ln3+-based solid luminescence materials due to the synergistic effect from AIE and AE. Also, benefiting from the film-processing ability and water solubility, Poly-Eu-1, -2, -3, and -4 could be employed with different application purposes. In the solution phase, they can be used as sensitive optical probes to detect trace amounts of H2O and D2O, and the limit of detection (LOD) of Poly-Eu-2 toward D2O in H2O is determined to be 7.8 ppm. This discovery is a novel strategy for the construction of D2O optical sensors with a totally intervention-free style.

Nucleolar stress regulates stromal-epithelial transition via NPM1 during decidualization.

Embryo implantation and decidualization are crucial steps during early pregnancy. We recently showed that nucleolar stress is involved in embryo implantation. This study was to explore whether nucleolar stress participates in mouse and human decidualization. Our data demonstrated that a low dose of actinomycin D (ActD) could induce nucleolar stress in stroma cells. Nucleolar stress promotes the stromal-epithelial transition during mouse in vitro decidualization through nucleophosmin1 (NPM1). Under nucleolar stress, Wnt family member 4 (Wnt4), a decidualization marker, is significantly increased, but decidua/trophoblast prolactin-related protein (Dtprp/Prl8a2) expression remains unchanged. For translational significance, we also examined the effects of nucleolar stress on human decidualization. Nucleolar stress stimulated by a low dose of ActD enhances human stromal-epithelial transition during human decidualization, but has no effects on the expression of insulin-like growth factor-binding protein 1 (IGFBP1). Our study indicates that nucleolar stress may promote only the mesenchymal-epithelial transition (MET), but not for all the molecular changes during decidualization.

Two aggregation-induced emission (AIE)-active reaction-type probes: for real-time detecting and imaging of superoxide anions.

Fluorescent probes are powerful tools for investigating reactive oxygen species (ROS) in living organisms. The overproduced "primary" ROS of superoxide anions (O2˙-) cause a chain of oxidative damage. In order to monitor O2˙- level fluctuations in living cells, we synthesized two reaction-type probes of TPA-DHP-1,2,3 and TPA-PPA-1,2,3, which were composed of an electron-rich triphenylamine (TPA) and the very active functional groups of dihydropyridine (DHP) and pyridinium (PPA). Intriguingly, DHP and PPA were able to carry out easy proton abstractions and nucleophilic reactions in the presence of O2˙-, resulting in the corresponding products with sharp wavelength shifts, and elevated fluorescence intensities. Therefore, undesirable background fluorescence interference can be reduced during the monitoring and imaging process. Meanwhile, the developed dual-channel monitoring strategy not only provides observations of the O2˙- level fluctuations, but could also be employed to image the dynamic accumulation process of probes in the different cell organelles. Therefore, the design could provide a simple, accurate and universal platform for biological applications in future research work.

Decidual expression and regulation of fatty acid desaturase 3 during mouse decidualization.

Decidualization is required for the successful establishment of pregnancy in rodents and primates. Fatty acid desaturase 3 (Fads3) belongs to the fatty acid desaturase family, which is a crucial enzyme for highly unsaturated fatty acid biosynthesis. However, the expression, regulation and function of Fads3 during early pregnancy in mice are still unknown. In this study, we examined Fads3 expression, regulation and function during mouse decidualization. The expression of Fads3 is detected in the subluminal stromal cells at implantation site on day 5 of pregnancy, but not at inter-implantation site and in day 5 pseudopregnant uteri. Compared to delayed implantation, Fads3 is strongly expressed after delayed implantation is activated by estrogen treatment. From days 6 to 8, Fads3 mRNA signals are significantly detected in the decidua. In ovariectomized mice, estrogen significantly stimulates Fads3 expression. However, estrogen has no effect on Fads3 expression in ovariectomized ERα-deficient mice, suggesting that estrogen regulation on Fads3 expression is ERα dependent. When ovariectomized mice were treated with progesterone, Fads3 expression is significantly increased by progesterone. Progesterone stimulation on Fads3 expression is also detected in cultured stromal cells, which is abrogated by RU486 treatment. These data indicate that progesterone upregulation on Fads3 expression is progesterone receptor-dependent. Fads3 knockdown by siRNA reduces in vitro decidualization of mouse stromal cells. Taken together, Fads3 may play an important role during mouse decidualization.

Alcohol Dehydrogenases and Acetaldehyde Dehydrogenases are Beneficial for Decidual Stromal Cells to Resist the Damage from Alcohol.

Aims: The aim of this study was to examine the effect of alcohol on the decidualization of human endometrial stromal cells during early pregnancy. Methods: During in vitro decidualization, human endometrial stromal cells were treated with alcohol, 4-methylpyrazole hydrochloride (FPZ), the inhibitor of alcohol dehydrogenases (ADHs), and tetraethylthiuram disulfide (DSF), the inhibitor of acetaldehyde dehydrogenases (ALDHs), respectively. Cell viability and decidualization were examined. Apoptosis and proliferation were also evaluated. Results: The findings showed that ADHs and ALDHs were up-regulated during decidualization. After alcohol treatment, the cell viability of decidual stromal cells was significantly higher than control, which was abrogated by FPZ or DSF. When cells were treated with alcohol, proliferation-related signal pathways were up-regulated in decidualized cells. Additionally, FOXO1 transcriptionally up-regulates ADH1B. Conclusion: Our study provided an evidence that highly expressed ADHs and ALDHs endow decidual stromal cells an ability to alleviate the harm from alcohol.

Warburg-like Glycolysis and Lactate Shuttle in Mouse Decidua during Early Pregnancy.

Decidualization is an essential process of maternal endometrial stromal cells to support pregnancy. Although it is known that enhanced glucose influx is critical for decidualization, the underlying mechanism in regulating glucose metabolism in decidua remains insufficiently understood. Here, we demonstrate that aerobic glycolysis-related genes and factors are all substantially induced during decidualization, indicating the existence of Warburg-like glycolysis in decidua. In vitro, progesterone activates hypoxia-inducible factor 1α (Hif1α) and c-Myc through Pi3k-Akt signaling pathway to maintain aerobic glycolysis in decidualizing cells. Knocking down of pyruvate kinase M2 (Pkm2) attenuates the induction of decidual marker gene. Decidual formation in vivo is also impaired by glycolysis inhibitor 3-bromopyruvate. Besides, lactate exporter monocarboxylate transporter 4 (Mct4) is induced in newly formed decidual cells, whereas lactate importer Mct1 and proliferation marker Ki-67 are complementarily located in the surrounding undifferentiated cells, which are supposed to consume lactate for proliferation. Hif1α activation is required for lactate-dependent proliferation of the undifferentiated cells. Inhibition of lactate flux leads to compromised decidualization and decelerated lactate-dependent proliferation. In summary, we reveal that Warburg-like glycolysis and local lactate shuttle are activated in decidua and play important roles for supporting early pregnancy.

Egr1 protein acts downstream of estrogen-leukemia inhibitory factor (LIF)-STAT3 pathway and plays a role during implantation through targeting Wnt4.

Embryo implantation is a highly synchronized process between an activated blastocyst and a receptive uterus. Successful implantation relies on the dynamic interplay of estrogen and progesterone, but the key mediators underlying embryo implantation are not fully understood. Here we show that transcription factor early growth response 1 (Egr1) is regulated by estrogen as a downstream target through leukemia inhibitory factor (LIF) signal transducer and activator of transcription 3 (STAT3) pathway in mouse uterus. Egr1 is localized in the subluminal stromal cells surrounding the implanting embryo on day 5 of pregnancy. Estrogen rapidly, markedly, and transiently enhances Egr1 expression in uterine stromal cells, which fails in estrogen receptor α knock-out mouse uteri. STAT3 is phosphorylated by LIF and subsequently recruited on Egr1 promoter to induce its expression. Our results of Egr1 expression under induced decidualization in vivo and in vitro show that Egr1 is rapidly induced after deciduogenic stimulus. Egr1 knockdown can inhibit in vitro decidualization of cultured uterine stromal cells. Chromatin immunoprecipitation data show that Egr1 is recruited to the promoter of wingless-related murine mammary tumor virus integration site 4 (Wnt4). Collectively, our study presents for the first time that estrogen regulates Egr1 expression through LIF-STAT3 signaling pathway in mouse uterus, and Egr1 functions as a critical mediator of stromal cell decidualization by regulating Wnt4.

[Chemical constituents of pattra medicine Euodia lepta].

OBJECTIVE: To study the chemical constituents of Pattra Medicine Euodia lepta in Xishuangbanna of Yunnan Province. METHODS: The chemical constituents were isolated and purified by chromatographic techniques, and identified by NMR, MS and other spectral methods. RESULTS: In 60% ethanol extract from the stems,and 95% ethanol extract from the leaves, six compounds and two compounds were isolated and identified as pachypodol( 1) ,3-(3-methyl-but-2-enyl )umbelliferone(2),7-demethylsuberosin (3),beta-sitosterol (4),3,7-dimethoxy kaempferol(5), euolitrine(6), sesamin(7) and p-O-geranyl coumaric acid(8), respectively. CONCLUSION: Compound 7 is obtained from Euodia genus for the first time,and compound 8 is obtained from domestic Euodia lepta for the first time.

Structure, function, and research progress of primary cilia in reproductive physiology and reproductive diseases.

Primary cilia, serving as the central hub for cellular signal transduction, possess the remarkable ability to translate diverse extracellular signals, both chemical and mechanical, into intracellular responses. Their ubiquitous presence in the reproductive system underscores their pivotal roles in various cellular processes including development, differentiation, and migration. Emerging evidence suggests primary cilia as key players in reproductive physiology and associated pathologies. Notably, primary cilia have been identified in granulosa cells within mouse ovaries and uterine stromal cells, and perturbations in their structure and function have been implicated in a spectrum of reproductive dysfunctions and ciliary-related diseases. Furthermore, disruptions in primary cilia-mediated signal transduction pathways under pathological conditions exacerbate the onset and progression of reproductive disorders. This review provides a comprehensive overview of current research progress on primary cilia and their associated signaling pathways in reproductive physiology and diseases, with the aim of furnishing theoretical groundwork for the prevention and management of primary cilia-related structural and functional abnormalities contributing to reproductive system pathologies.

Blastocyst-Derived Lactic Acid May Regulate S100A6 Expression and Function in Mouse Decidualization via Stimulation of Uterine Epithelial Arachidonic Acid Secretion.

(1) Background: Inflammatory responses are implicated in embryo implantation, decidualization, pregnancy maintenance and labor. Both embryo implantation and decidualization are essential to successful pregnancy in rodents and primates. S100A6 is involved in inflammation, tumor development, apoptosis and calcium homeostasis. S100A6 is strongly expressed in mouse decidua, but the underlying mechanisms of how S100A6 regulates implantation and decidualization are poorly defined. (2) Methods: Mouse endometrial stromal and epithelial cells are isolated from day 4 pseudopregnant mouse uteri. Both immunofluorescence and Western blotting are used to analyze the expression and localization of proteins. The molecular mechanism is verified in vitro by Western blotting and the quantitative polymerase chain reaction. (3) Results: From days 4 to 8 of pregnancy, S100A6 is specifically expressed in mouse subluminal stromal cells. Blastocyst-derived lactic acid induces AA secretion by activating the luminal epithelial p-cPLA2. The epithelial AA induces stromal S100A6 expression through the COX2/PGI2/PPAR δ pathway. Progesterone regulates S100A6 expression through the progesterone receptor (PR). S100A6/RAGE signaling can regulate decidualization via EGFR/ERK1/2 in vitro. (4) Conclusions: S100A6, as an inflammatory mediator, is important for mouse implantation and decidualization.

Tryptophan in the mouse diet is essential for embryo implantation and decidualization.

Introduction: Nutritional deficiency occurs frequently during pregnancy and breastfeeding. Tryptophan (Trp), an essential amino acid which is critical for protein synthesis, serves as the precursor for serotonin, melatonin, and kynurenine (Kyn). The imbalance between serotonin and kynurenine pathways in Trp metabolism is closely related to inflammation and depression. This study assessed the effects of Trp deficiency on mouse early pregnancy. Methods: Embryo implantation and decidualization were analyzed after female mice had been fed diets containing 0.2% Trp (for the control group), 0.062% Trp (for the low Trp group) and 0% Trp (for the Trp-free group) for two months. The uteri of the mice were collected on days 4, 5, and 8 of pregnancy for further analysis. Results: On day 8 of pregnancy, the number of implantation sites were found to be similar between the control and the low Trp groups. However, no implantation sites were detected in the Trp-free group. On day 5 of pregnancy, plane polarity- and decidualization-related molecules showed abnormal expression pattern in the Trp-free group. On day 4 of pregnancy, there was no significant difference in uterine receptivity molecules between the low-Trp group and the control group, but uterine receptivity was abnormal in the Trp-free group. At implantation sites of the Trp-free group, IDO and AHR levels were markedly elevated. This potentially increased levels of Kyn, 2-hydroxy estradiol, and 4-hydroxy estradiol to affect decidualization. Conclusions: Trp-free diet may impair decidualization via the IDO-KYN-AHR pathway.

Proteomic profiling of expression of proteasomal subunits from livers of mice treated with diethylnitrosamine.

The liver plays a central role in transforming and clearing chemicals and is susceptible to the toxicity from these agents. Diethylnitrosamine is metabolized primarily in the liver by cytochrome P-450 and can cause DNA damage. The 26S proteasome is a large proteolytic complex that degrades ubiquitinated proteins, and regulates many physiological processes. We used proteomics-based approaches to examine expressional differences of liver proteasomal subunits from diethylnitrosamine-treated mice. The expression of most proteasomal subunits was observed to be upregulated in the analysis of 2DE and MALDI-TOF MS/MS. Some of these differentially expressed proteasomal subunits were further confirmed by Western blot, RT-PCR, and immunohistochemistry. Our results provided useful information on the relationship between the proteasomal complex and related diseases.