Progesterone in pregnancy; receptor-ligand interaction and signaling pathways

The impact of reproductive hormones on T cell immunity; normal and assisted reproductive cycles

During pregnancy, a unique immune milieu is established systemically and locally at the maternal-fetal interface. While preparing for embryonic implantation, endometrial effectors significantly change their proportions and function, which are synchronized with hormonal changes. During assisted reproductive technology cycles, various cytokines, chemokines, and immune factors dynamically change with the altered receptor expressions on the immune effectors. Thus, the hormonal regulation of immune effectors is critical to maintaining the immune milieu. In this review, hormonal effects on T cell subsets are reviewed. Sex hormones affect T cell ontogeny and development, consequently affecting their functions. Like other T cell subsets, CD4+ T helper (Th) cells are modulated by estrogen, where low estrogen concentration promotes Th1-driven cell-mediated immunity in the uterus and in vitro by enhancing IFN-γ production, while a high estrogen level decreases it. The abundance and differentiation of T regulatory (Treg) cells are controlled by estrogen, inducing Treg expansion. Conversely, progesterone maintains immune homeostasis by balancing Th1/Th2 and Th17/Treg immunity, leading to maternal-fetal tolerance. Therefore, the understanding of the hormonal impact on various T cell subsets during the reproductive cycles is critical to improving reproductive outcomes in women with recurrent pregnancy losses, repeated implantation failures, and undergoing assisted reproductive cycles.

Placental progesterone and its receptor in HIV-infected pre-eclamptic women

Given the high prevalence of HIV infection and pre-eclampsia (PE) in South Africa, this study evaluated and compared the placental immunostaining of progesterone (P) and progesterone receptors (PR) in the synergy of HIV-infected PE compared to normotensive pregnant women using immunohistochemistry interfaced with morphometric image analysis. Progesterone immunostaining was expressed widely across exchange and conducting villi within mesenchymal, endothelial, and trophoblast cells. In contrast, PR was expressed within syncytiotrophoblasts and was absent within endothelial cells. In exchange villi, P and PR immuno-expression was significantly lower in PE compared to the normotensive group (p = < 0.0001 and p = < 0.0001, respectively) and within the early-onset pre-eclampsia (EOPE) compared to the late-onset pre-eclampsia (LOPE) group (p = < 0.0001 and p = < 0.0001, respectively). Progesterone immuno-expression was significantly lower in the HIV+ compared to the HIV- group (p = < 0.0001), whilst PR was non-significant. In conducting villi, P and PR immuno-expression was significantly lower in the EOPE compared to the LOPE group (p = < 0.0001 and p = < 0.0001, respectively) and in the HIV+ compared to the HIV- group (p = < 0.0001 and p = 0.0009, respectively). Progesterone immuno-expression was slightly higher in the PE compared to normotensive group, and PR immuno-expression was non-significant. There was a significant difference between P and PR within exchange versus conducting villi regardless of pregnancy type, with villi type accounting for 34.47% and 15.28% of total variance for P and PR, respectively. Placental P and PR immuno-expression is downregulated in the duality of PE and HIV+ infection. The use of combined antiretroviral therapy (cART) may result in defective P synthesis, which causes insufficient binding to its receptors. Consequently, PI3K/AKT, JAK-STAT, and MAPK signalling pathways are affected, impairing trophoblast invasion and leading to pre-eclampsia development. Notably, the decrease in P and PR immuno-expression in EOPE validates their effect on placentation.

Oral micronized progesterone versus vaginal progesterone for luteal phase support in fresh embryo transfer cycles: a multicenter, randomized, non-inferiority trial

STUDY QUESTION

Does oral micronized progesterone result in a non-inferior ongoing pregnancy rate compared to vaginal progesterone gel as luteal phase support (LPS) in fresh embryo transfer cycles?

SUMMARY ANSWER

The ongoing pregnancy rate in the group administered oral micronized progesterone 400 mg per day was non-inferior to that in the group administered vaginal progesterone gel 90 mg per day.

WHAT IS KNOWN ALREADY

LPS is an integrated component of fresh IVF, for which an optimal treatment regimen is still lacking. The high cost and administration route of the commonly used vaginal progesterone make it less acceptable than oral micronized progesterone; however, the efficacy of oral micronized progesterone is unclear owing to concerns regarding its low bioavailability after the hepatic first pass.

STUDY DESIGN, SIZE, DURATION

This non-inferiority randomized trial was conducted in eight academic fertility centers in China from November 2018 to November 2019. The follow-up was completed in April 2021.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 1310 infertile women who underwent their first or second IVF cycles were enrolled. On the day of hCG administration, the patients were randomly assigned to one of three groups for LPS: oral micronized progesterone 400 mg/day (n = 430), oral micronized progesterone 600 mg/day (n = 440) or vaginal progesterone 90 mg/day (n = 440). LPS was started on the day of oocyte retrieval and continued till 11-12 weeks of gestation. The primary outcome was the rate of ongoing pregnancy.

MAIN RESULTS AND THE ROLE OF CHANCE

In the intention-to-treat analysis, the rate of ongoing pregnancy in the oral micronized progesterone 400 mg/day group was non-inferior to that of the vaginal progesterone gel group [35.3% versus 38.0%, absolute difference (AD): -2.6%; 95% CI: -9.0% to 3.8%, P-value for non-inferiority test: 0.010]. There was insufficient evidence to support the non-inferiority in the rate of ongoing pregnancy between the oral micronized progesterone 600 mg/day group and the vaginal progesterone gel group (31.6% versus 38.0%, AD: -6.4%; 95% CI: -12.6% to -0.1%, P-value for non-inferiority test: 0.130). In addition, we did not observe a statistically significant difference in the rate of live births between the groups.

LIMITATIONS, REASONS FOR CAUTION

The primary outcome of our trial was the ongoing pregnancy rate; however, the live birth rate may be of greater clinical interest. Although the results did not show a difference in the rate of live births, they should be confirmed by further trials with larger sample sizes. In addition, in this study, final oocyte maturation was triggered by hCG, and the findings may not be extrapolatable to cycles with gonadotropin-releasing hormone agonist triggers.

WIDER IMPLICATIONS OF THE FINDINGS

Oral micronized progesterone 400 mg/day may be an alternative to vaginal progesterone gel in patients reluctant to accept the vaginal route of administration. However, whether a higher dose of oral micronized progesterone is associated with a poorer pregnancy rate or a higher rate of preterm delivery warrants further investigation.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by a grant from the National Natural Science Foundation of China (82071718). None of the authors have any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

This trial was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the number ChiCTR1800015958.

TRIAL REGISTRATION DATE

May 2018.

DATE OF FIRST PATIENT’S ENROLMENT

November 2018.

The Next Frontier in ART: Harnessing the Uterine Immune Profile for Improved Performance

Assisted reproduction techniques have improved considerably in recent decades, but despite these advances, success rates remain relatively low. Endometrial immune profiling involves the analysis of cytokine biomarkers in the endometrium during the mid-luteal phase. This profiling aims to provide insights into the immune environment of the uterus. The aim is to identify immune disturbances and thus guide the development of personalized therapeutic approaches. The first part of the review looks back at the emergence of innovative concepts, highlighting the specificity of the human uterine environment at the time of implantation. Based on this new knowledge, biomarkers have been selected for endometrial immune profiling. The second part details the results of clinical studies conducted over the last ten years. These clinical results suggest that this approach can increase the rate of live births in patients suffering from repeated implantation failures or repeated pregnancy loss. Uterine immune profiling represents a clinical innovation that can significantly improve the performance of medically assisted reproduction treatments through personalized strategies tailored to the local immune profile. Innovation in personalized medicine for assisted reproduction is crucial to improving the success rates of fertility treatments, while reducing the risks and costs associated with ineffective or unnecessary interventions.

The impact of menopause on multiple sclerosis

Menopause, defined as the permanent cessation of ovarian function, represents a period of significant fluctuation in sex hormone concentrations. Sex hormones including oestrogen, progesterone, testosterone and anti-Mullerian hormone are thought have neuroinflammatory effects and are implicated in both neuroprotection and neurodegeneration. Sex hormones are thought to have a role in modifying clinical trajectory in multiple sclerosis (MS) throughout the lifespan. Multiple sclerosis predominantly effects women and is typically diagnosed early in a woman's reproductive life. Most women with MS will undergo menopause. Despite this, the effect of menopause on MS disease course remains unclear. This review examines the relationship between sex hormones and MS disease activity and clinical course, particularly around the time of menopause. It will consider the role of interventions such as exogenous hormone replacement therapy in modulating clinical outcomes in this period. Understanding the impact of menopause on multiple sclerosis is fundamental for delivering optimal care to women with MS as they age and will inform treatment decisions with the aim of minimising relapses, disease accrual and improving quality of life.

The role of progesterone and the progesterone receptor in cancer: progress in the last 5 years

INTRODUCTION

Patients with various advanced cancers devoid of nuclear progesterone receptors (nPR) have demonstrated increased quality and length of life when treated with the PR modulator mifepristone, which likely works by interacting with membrane PRs (mPR).

AREAS COVERED

Two immunomodulatory proteins are discussed that seem to play a role in cancers that proliferate whether the malignant tumor is positive or negative for the nPR. These two proteins are the progesterone receptor membrane component-1 (PGRMC-1) and the progesterone-induced blocking factor (PIBF). Both PGRMC-1 and the parent form of PIBF foster increased tumor aggressiveness, whereas splice variants of the 90 kDa form of PIBF inhibit immune response against cancer cells.

EXPERT OPINION

The marked clinical improvement following 200-300 mg of mifepristone is likely related to blocking PIBF. In the low dosage used, mifepristone likely acts as an agonist for PGRMC-1 protein. Mifepristone may be less effective for cancers positive for the nPR because the nPR may be protective and blocking it may have detrimental effects. Based on this hypothetical model, the development of other potential treatment options to provide even greater efficacy for treating cancer are discussed.

Gradient Boosting Machine Learning Model for Defective Endometrial Receptivity Prediction by Macrophage-Endometrium Interaction Modules

Background

A receptive endometrium is a prerequisite for successful embryo implantation. Mounting evidence shows that nearly one-third of infertility and implantation failures are caused by defective endometrial receptivity. This study pooled 218 subjects from multiple datasets to investigate the association of the immune infiltration level with reproductive outcome. Additionally, macrophage-endometrium interaction modules were constructed to explore an accurate and cost-effective approach to endometrial receptivity assessment.

Methods

Immune-infiltration levels in 4 GEO datasets (n=218) were analyzed and validated through meta-analysis. Macrophage-endometrium interaction modules were selected based on the weighted gene co-expression network in GSE58144 and differentially expressed genes dominated by GSE19834 dataset. Xgboost, random forests, and regression algorithms were applied to predictive models. Subsequently, the efficacy of the models was compared and validated in the GSE165004 dataset. Forty clinical samples (RT-PCR and western blot) were performed for expression and model validation, and the results were compared to those of endometrial thickness in clinical pregnancy assessment.

Results

Altered levels of Mϕs infiltration were shown to critically influence embryo implantation. The three selected modules, manifested as macrophage-endometrium interactions, were enrichment in the immunoreactivity, decidualization, and signaling functions and pathways. Moreover, hub genes within the modules exerted significant reproductive prognostic effects. The xgboost algorithm showed the best performance among the machine learning models, with AUCs of 0.998 (95% CI 0.994-1) and 0.993 (95% CI 0.979-1) in GSE58144 and GSE165004 datasets, respectively. These results were significantly superior to those of the other two models (random forest and regression). Similarly, the model was significantly superior to ultrasonography (endometrial thickness) with a better cost-benefit ratio in the population.

Conclusion

Successful embryo implantation is associated with infiltration levels of Mϕs, manifested in genetic modules involved in macrophage-endometrium interactions. Therefore, utilizing the hub genes in these modules can provide a platform for establishing excellent machine learning models to predict reproductive outcomes in patients with defective endometrial receptivity.

Steroid hormones of the octopus self-destruct system

Among all invertebrates, soft-bodied cephalopods have the largest central nervous systems and the greatest brain-to-body mass ratios, yet unlike other big-brained animals, cephalopods are unusually short lived.^1-5 Primates and corvids survive for many decades, but shallow-water octopuses, such as the California two-spot octopus (Octopus bimaculoides), typically live for only 1 year.^6,7 Lifespan and reproduction are controlled by the principal neuroendocrine center of the octopus: the optic glands, which are functional analogs to the vertebrate pituitary gland.^8-10 After mating, females steadfastly brood their eggs, begin fasting, and undergo rapid physiological decline, featuring repeated self-injury and leading to death.¹¹ Removal of the optic glands completely reverses this life history trajectory,¹⁰ but the signaling factors underlying this major life transition are unknown. Here, we characterize the major secretions and steroidogenic pathways of the female optic gland using mass spectrometry techniques. We find that at least three pathways are mobilized to increase synthesis of select sterol hormones after reproduction. One pathway generates pregnane steroids, known in other animals to support reproduction.^12-16 Two other pathways produce 7-dehydrocholesterol and bile acid intermediates, neither of which were previously known to be involved in semelparity. Our results provide insight into invertebrate cholesterol pathways and confirm a remarkable unity of steroid hormone biology in life history processes across Bilateria.

A New Perspective on Thyroid Hormones: Crosstalk with Reproductive Hormones in Females

Accumulating evidence has shown that thyroid hormones (THs) are vital for female reproductive system homeostasis. THs regulate the reproductive functions through thyroid hormone receptors (THRs)-mediated genomic- and integrin-receptor-associated nongenomic mechanisms, depending on TH ligand status and DNA level, as well as transcription and extra-nuclear signaling transduction activities. These processes involve the binding of THs to intracellular THRs and steroid hormone receptors or membrane receptors and the recruitment of hormone-response elements. In addition, THs and other reproductive hormones can activate common signaling pathways due to their structural similarity and shared DNA consensus sequences among thyroid, peptide, and protein hormones and their receptors, thus constituting a complex and reciprocal interaction network. Moreover, THs not only indirectly affect the synthesis, secretion, and action of reproductive hormones, but are also regulated by these hormones at the same time. This crosstalk may be one of the pivotal factors regulating female reproductive behavior and hormone-related diseases, including tumors. Elucidating the interaction mechanism among the aforementioned hormones will contribute to apprehending the etiology of female reproductive diseases, shedding new light on the treatment of gynecological disorders.

Circulating Innate Lymphoid Cells Exhibit Distinctive Distribution During Normal Pregnancy

Over the past decades, the investigation of innate lymphoid cells (ILCs) has revealed their significance in successful pregnancy. Sex hormones, such as estradiol and progesterone, show specific changes during pregnancy and modulate both adaptive and innate immune systems. ILC subset distribution in peripheral blood of pregnant women and its potential association with sex hormone levels have not been well revealed. Peripheral blood was obtained from healthy non-pregnant, early-pregnant, and late-pregnant women. Radioimmunoassay was performed to measure plasma estradiol and progesterone levels. The levels of type 1 ILCs (ILC1s), type 2 ILCs (ILC2s), type 3 ILCs (ILC3s), and total ILCs as well as estrogen and progesterone receptors of ILC2s in peripheral blood were analyzed using flow cytometry. The proportion of total ILCs and distribution of ILC subsets in peripheral blood changed dynamically during pregnancy. Compared to non-pregnant women, late-pregnant women displayed significantly higher proportion of circulating ILCs, among which ILC2s accounted for the majority in late-pregnant women while a smaller part in others, and ILC3s displayed the opposite. Plasma estradiol and progesterone levels elevated while pregnancy proceeded and the expression of their receptors in ILC2s increased consisted with the proportion of circulating ILC2s. Our work first observed the existence of progesterone receptors in human circulating ILC2s and revealed the distribution pattern of circulating ILC subsets and their interrelation with plasma sex hormone levels during pregnancy. Our results suggested that the estradiol and progesterone levels might partly influence the distribution of circulating ILC subsets and implied the interplay between circulating ILCs and pregnancy.

Identification of Profound Metabolic Alterations in Human Dendritic Cells by Progesterone Through Integrated Bioinformatics Analysis

Maintaining the homeostasis of the decidual immune microenvironment at the maternal-fetal interface is essential for reproductive success. Dendritic cells (DCs) are the professional antigen-presenting cells and dominate this balance of immunogenicity and tolerance. Progesterone (P4) is highlighted as the “hormone of pregnancy” in most eutherian mammals because of its regulatory role in immune-endocrine behavior during pregnancy. Recent studies have shown that P4 is associated with the differentiation and function of DCs, however, the underlying mechanisms remain unidentified. In addition, while progress in the field of immunometabolism has highlighted the intimate connections between the metabolism phenotype and the immunogenic or tolerogenic fate of DCs, whether P4 can affect DCs metabolism and thus exert a functional manipulation has not yet been explored. In this study, we acquired human peripheral blood monocyte-derived DCs and conducted RNA sequencing (RNA-seq) on immature DCs (iDCs), P4-treated DCs (pDCs), and mature DCs (mDCs), aiming to comprehensively assess the effects of P4 on DCs. Our results showed pDCs performed a distinct differentially expressed genes (DEGs) profile compared with iDCs or mDCs. Further functional enrichment and weighted gene co-expression network (WGCNA) analysis found that these DEGs were related not only to the cellular components but also to the significant metabolic activities, including mitochondrial oxidative phosphorylation (OXPHOS) and fatty acid metabolism. In addition, these changes may be involved in the activation of various signaling pathways of PI3K/Akt/mTOR, AMPK/PGC1-α, and PPAR-γ. In summary, our work suggested that P4 induced profound metabolic alterations of mitochondrial OXPHOS and fatty acid metabolism in DCs. Our findings may provide new insights into the role of P4 in DCs.

Progesterone-induced blocking factor-mediated Th1/Th2 balance correlates with fetal arrest in women who underwent in vitro fertilization and embryo transfer

The role of progesterone-induced blocking factor (PIBF)-mediated Th1/Th2 balance in delivery outcomes of in vitro fertilization and embryo transfer (IVF-ET) has not been fully elucidated. In this study, 73 infertile women with successful IVF-ET were enrolled (16 fetal arrests and 57 live births). PIBF and IL-4 levels were significantly lower in the fetal arrest group than in the live birth group (p < 0.05). TNF-α level and Th1/Th2 ratios were significantly higher in the fetal arrest group than in the live birth group (p < 0.05). High TNF-α level and Th1/Th2 ratios were risk factors for fetal arrest, whereas increased PIBF and IL-4 levels were protective factors (P < 0.05). Increased TNF-α/IL-4 exhibited relatively strong predictive value for fetal arrest (AUC, 0.855; sensitivity, 93.8%; specificity, 71.9%). In summary, the PIBF-mediated Th1/Th2 balance is closely correlated with delivery outcomes of IVF-ET. TNF-α/IL-4 may be a predictive marker of fetal arrest.

Progesterone-induced blocking factor improves blood pressure, inflammation, and pup weight in response to reduced uterine perfusion pressure (RUPP)

Preeclampsia (PE) is characterized by new-onset hypertension in association with elevated natural killer (NK) cells and inflammatory cytokines, which are likely culprits for decreased fetal weight during PE pregnancies. As progesterone increases during normal pregnancy, it stimulates progesterone-induced blocking factor (PIBF). PIBF has been shown to decrease inflammation and cytolytic NK cells, both of which are increased during PE. We hypothesized that PIBF reduces inflammation as a mechanism to improve hypertension in the preclinical reduced uterine perfusion pressure (RUPP) rat model of PE. PIBF (2.0 µg/mL) was administered intraperitoneally on gestational day 15 to either RUPP or normal pregnant (NP) rats. On day 18, carotid catheters were inserted. Mean arterial blood pressure (MAP) and samples were collected on day 19. MAP in NP rats (n = 11) was 100 ± 2 mmHg and 105 ± 3 mmHg in NP + PIBF rats (n = 8) and 122 ± 1 mmHg in RUPP rats (n = 10), which improved to 110 ± 2 mmHg in RUPP + PIBF rats (n = 11), P < 0.05. Pup weight was 2.4 ± 0.1 g in NP, 2.5 ± 0.1 g in NP + PIBF, 1.9 ± 0.1 g in RUPP, and improved to 2.1 ± 0.1 g in RUPP + PIBF rats. Circulating and placental cytolytic NK cells, IL-17, and IL-6 were significantly reduced while IL-4 and T helper (TH) 2 cells were significantly increased in RUPP rats after PIBF administration. Importantly, vasoactive pathways preproendothelin-1, nitric oxide, and soluble fms-Like tyrosine Kinase-1 (sFlt-1) were normalized in RUPP + PIBF rats compared with RUPP rats, P < 0.05. Our findings suggest that PIBF normalized IL-4/TH2 cells, which was associated with improved inflammation, fetal growth restriction, and blood pressure in the RUPP rat model of PE.

The hormonal control of the uterus of the bat Myotis nigricans during its different reproductive phases: emphasis on progesterone and estradiol

Myotis nigricans is a species of bat from the Vespertilionidae family that is endemic of the Neotropical region. Its insectivorous feeding habit plus its large range of prey species, great geographical dispersion, wide colonies, and anthropomorphized behavior make this species an important ecological agent that acts in the control of nocturnal insects. Reproductively, M. nigricans presents geographic variations, having different patterns of reproduction according to its geographical location. Despite these extremely interesting characteristics, no more detailed study of the hormonal control of the reproduction of this species has been conducted. Therefore, the aim of the present study was to evaluate the variations in serum hormone concentrations and in uterine hormonal control of this bat during its different reproductive phases. Twenty adult females were collected, divided into four (4) sample groups, according to the reproductive status (nonreproductive, initial, and advanced pregnancy and lactating), and submitted to hormone dosage and immunohistochemical analyses. The results demonstrated that the uterus of M. nigricans is strongly regulated by the interaction/cross-talk between serum concentrations of estradiol (E2) and progesterone with their respective hormone receptors. Significant increases in the concentration of E2 and progesterone are needed to regulate the early pregnancy. The persistence of the corpus luteum throughout pregnancy is necessary, since its placenta does not express aromatase. The expressions of ERα and PR appear to be synchronized in order to coordinate a large portion of the processes that occur inside the uterus of M. nigricans during pregnancy and lactation.

Oral nomegestrol acetate and transdermal 17-beta-estradiol for preventing post-partum relapses in multiple sclerosis: The POPARTMUS study

Background:

Sex steroids could explain the course of multiple sclerosis (MS) in pregnancy.

Objective:

To compare the annualized relapse rate (ARR) 12 weeks post-partum in women treated with nomegestrol acetate (NOMAc) and 17-beta-estradiol (E2) versus placebo.

Methods:

POPARTMUS is a randomized, proof-of-concept trial in women with MS, receiving oral NOMAc 10 mg/day and transdermal estradiol 75 µg/week, or placebo.

Results:

Recruitment was stopped prematurely due to slow inclusions ( n = 202). No treatment effect was observed on ARR after 12 weeks (sex steroids = 0.90 (0.58–1.39), placebo = 0.97 (0.63–1.50) ( p = 0.79)).

Conclusion:

POPARTMUS failed showing efficacy of a NOMAc–E2 combination in preventing post-partum relapses.

Detection of Vaginal Metabolite Changes in Premature Rupture of Membrane Patients in Third Trimester Pregnancy: a Prospective Cohort Study

Premature rupture of membranes (PROM) is usually associated with pregnant and neonatal complications. Most of the PROM cases are caused by ascending asymptomatic genital infection. In China, PROM (15.3%) is more common than spontaneous preterm labor (7.3%) and leads to more adverse pregnancy outcomes. Here, we designed a prospective cohort study to measure the metabolomics changes in vaginal swab samples and explored their potential contribution to PROM. A total of 260 differentially expressed metabolites were identified and further analyzed. In the PROM group, N-acetyl-D-galactosamine and sucrose were downregulated (P = 0.0025, P = 0.0195, respectively), both of which are the upstream metabolites of the glycolysis pathway. Furthermore, estriol 3-sulfate 16-glucuronide (P = 0.0154) and 2-methoxy-17beta-estradiol 3-glucosiduronic acid (P = 0.004), two final metabolites in steroid hormone biosynthesis, were both downregulated in the PROM group. Finally, we found two catechin metabolites (epigallocatechin-7-glucuronide, P = 0.0009; 4'-methyl-epigallocatechin-7-glucuronide, P = 0.01) as well as DL-citrulline (P = 0.0393) were also significantly downregulated in the PROM group compared with the healthy control (HC) group, which are related to important antioxidant and anti-inflammatory activities in the human body. Altogether, metabolite changes in glycolysis, steroid hormone biosynthesis, and antioxidant/anti-inflammatory pathways may contribute to (or be a consequence of) vaginal dysbiosis and PROM. Metabolite pathway analysis is a new and promising approach to further investigate the mechanism of PROM and help prevent its unfavorable pregnant outcomes at a functional level. Trial registration number: ChiCTR2000034721.

17-Hydroxyprogesterone caproate improves hypertension and renal endothelin-1 in response to sFlt-1 induced hypertension in pregnant rats

Preeclampsia (PE) is characterized by new onset hypertension in association with elevated soluble fms-like tyrosine kinase-1 (sFlt-1) and preproendothelin-1 (PPET-1) levels. Currently there is no effective treatment for PE except for early delivery of the fetal placental unit, making PE a leading cause for premature births worldwide. Administration of 17-hydroxyprogesterone caproate (17-OHPC) is used for prevention of recurrent preterm birth. This study was designed to test the hypothesis that 17-OHPC improves hypertension and ET-1 in response to elevated sFlt-1 in pregnant rats. sFlt-1 was infused into normal pregnant (NP) Sprague-Dawley rats (3.7 μg·kg^-1·day^-1 for 6 days, gestation days 13-19) in the presence or absence of 17-OHPC (3.32 mg/kg) administered via intraperitoneal injection on gestational days 15 and 18. Mean arterial blood pressure (MAP), pup and placenta weights, renal cortex PPET-1 mRNA levels and nitrate-nitrite levels were measured on GD 19. Infusion of sFlt-1 into NP rats elevated mean arterial pressure (MAP) compared with control NP rats: 115 ± 1 (n = 13) vs. 99 ± 2 mmHg (n = 12, p < 0.05). 17-OHPC attenuated this hypertension reducing MAP to 102 ± 3 mmHg in sFlt-1 treated pregnant rats (n = 8). Neither pup nor placental weight was affected by sFlt-1 or 17-OHPC. Importantly, renal cortex PPET-1 mRNA levels were elevated 3 fold in NP + sFlt-1 rats compare to NP rats, which decreased with 17-OHPC administration. Plasma nitrate-nitrite levels were 44 ± 9 µM in NP rats (n = 9), 20 ± 3 µM in NP + sFlt-1 (n = 7), which increased to 42 ± 11 µM NP + sFlt-1 + 17OHPC (n = 6). Administration of 17-OHPC improves clinical characteristics of preeclampsia in response to elevated sFlt-1 during pregnancy.

Functional significance of lymphocytes in pregnancy and lymphocyte immunotherapy in infertility: A comprehensive review and update

During pregnancy, the fetal-maternal interface underlies several dynamic alterations to permit the fetus to be cultivated and developed in the uterus, in spite of being identifies by the maternal immune system. A large variety of decidual leukocyte populations, including natural killer cells, NKT cells, innate lymphoid cells, dendritic cells, B cells, T cells, subpopulations of helper T cells play a vital role in controlling the trophoblast invasion, angiogenesis as well as vascular remodeling. In contrast, several regulatory immunosuppressive mechanisms, including regulatory T cells, regulatory B cells, several cytokines and mediators are involved in maintain the homeostasis of immune system in the fetal-maternal interface. Nonetheless, aberrant alterations in the balance of immune inflammatory or immunosuppressive arms have been associated with various pregnancy losses and infertilities. As a result, numerous strategies have been developed to revers dysregulated balance of immune players to increase the chance of successful pregnancy. Lymphocyte immunotherapy has been developed through utilization of peripheral white blood cells of the husband or others and administered into the mother to confer an immune tolerance for embryo's antigens. However, the results have not always been promising, implying to further investigations to improve the approach. This review attempts to clarify the involvement of lymphocytes in contributing to the pregnancy outcome and the potential of lymphocyte immunotherapy in treatment of infertilities with dysregulated immune system basis.

Endometrial Immune Profiling: A Method to Design Personalized Care in Assisted Reproductive Medicine

Objective: To assess the efficiency of the endometrial immune profiling as a method to design personalized care to enhance the pregnancy rate in a large heterogeneous infertile population. We hypothesized that some reproductive failures could be induced by a uterine immune dysregulation which could be identified and corrected with a targeted plan. Design: Prospective cohort study. Setting: Multicentric study. Intervention(s) and Main outcome measure(s): One thousand and seven hundred thirty-eight infertile patients had an immune profiling on a timed endometrial biopsy between 2012 and 2018. This test documented the absence or the presence of an endometrial immune dysregulation and identified its type. In case of dysregulation, a targeted personalized plan was suggested to the treating clinician aiming to supply the anomaly. One year after the test, the clinician was contacted to provide the outcome of the subsequent embryo transfer with the applied suggested plan. Result(s): After testing, 16.5% of the patients showed no endometrial immune dysregulation, 28% had a local immune under-activation, 45% had a local immune over-activation, and 10.5% had a mixed endometrial immune profile. In patients with a history of repeated implantation failures (RIF) or recurrent miscarriages (RM), the pregnancy rate was significantly higher if an endometrial dysregulation was found and the personalized plan applied, compared to the patients with an apparent balanced immune profile (respectively 37.7 and 56% vs. 26.9 and 24%, p < 0.001). In contrast, in good prognosis IVF (in vitro fertilization) subgroup and patients using donor eggs, this difference was not significant between dysregulated and balanced subgroups, but higher pregnancy rates were observed in absence of dysregulation. For patients with immune over-activation, pregnancy rates were significantly higher for patients who had a test of sensitivity, regarding the type of immunotherapy introduced, when compared to the ones who did not (51 vs. 39.9%, p = 0.012). Conclusion(s): Local endometrial immunity appears to be a new and important parameter able to influence the prognosis of pregnancy. Targeted medical care in case of local immune dysregulation resulted in significantly higher pregnancy rates in RIF and RM patients.

Medawar's Paradox and Immune Mechanisms of Fetomaternal Tolerance

Brazilian-born British biologist Dr. Peter Medawar played an integral role in developing the concepts of immunologic rejection and tolerance, which led to him receiving the Nobel Prize "for the discovery of acquired immunologic tolerance" and eventually made organ transplantation a reality. However, at the time of his early work in tolerance, a paradox to his theories was brought to his attention; how was pregnancy possible? Pregnancy resembles organ transplantation in that the fetus, possessing paternal antigens, is a semi-allogeneic graft that can survive without immunosuppression for 9 months. To answer this question, Medawar proposed three hypotheses of how a mother supports her fetus in utero, now known as "Medawar's Paradox." The mechanisms that govern fetomaternal tolerance are still incompletely understood but may provide critical insight into how to achieve immune tolerance in organ transplantation. Here, we review current understanding of the immune factors responsible for fetomaternal tolerance during pregnancy and discuss the potential implications for advances in transplantation science.

Characterisation of serum progesterone and progesterone-induced blocking factor (PIBF) levels across trimesters in healthy pregnant women

Progesterone-induced blocking factor (PIBF), which plays an important role in maintaining healthy pregnancies, has shown great promise as a prognostic biomarker for threatened miscarriage. To better characterise the physiological trends of progesterone and PIBF, we analysed serum progesterone and PIBF concentrations in healthy non-pregnant and pregnant women across trimesters. We saw increasing concentrations of progesterone and PIBF in pregnant women with advancing trimesters. The serum progesterone and PIBF percentiles across gestational age in healthy pregnancies can be used as a guide for the formulation of reference ranges. We also demonstrated a significant positive correlation between progesterone and PIBF levels. This study demonstrates increasing progesterone and PIBF concentrations in later trimesters and underscores the importance of progesterone and PIBF in healthy pregnancies. Characterisation of progesterone and PIBF across gestational age in healthy pregnant women may help to prognosticate pregnancy viability and support further research into the importance of progesterone and PIBF in the maintenance of healthy pregnancies.

Progesterone receptor membrane component 1 (PGRMC1)-mediated progesterone effect on preimplantation development of in vitro produced porcine embryos

Progesterone is a steroid hormone well known for its significant role in the reproduction process of mammals. Numerous studies have reported on the regulation of progesterone during implantation, pregnancy and parturition, but there are fewer studies on progesterone in relation to the early stages of embryo development. In the present study, we investigated the effects of progesterone during the development of in vitro produced porcine embryos. First, gene expression of various progesterone receptors in the in vitro produced porcine embryos were analyzed. PGRMC1 and PGRMC2 (progesterone receptor membrane component 1 and 2) showed distinct expression. Next, the embryos were treated with two concentrations of progesterone (10 nM and 100 nM) for two different durations (from day 0 and from day 4) to compare the developmental rates, cell numbers, and apoptosis rates of day 7 blastocysts. The experimental groups in both durations showed similarly increased blastocyst cell numbers and decreased apoptosis rates when treated with 100 nM progesterone. Furthermore, the expression levels of PGRMC1, PGRMC2, PAIRBP1 (plasminogen activator inhibitor RNA-binding protein 1), and apoptosis-related genes were examined in blastocysts and showed significant increases in the 100 nM treatment group compared to the control group. Subsequently, the embryos were treated with the PGRMC1 inhibitor, AG-205, and developmental rates, cell numbers, and apoptosis rates of day 7 blastocysts were compared. In addition, 100 nM progesterone was treated simultaneously with AG-205 to test if the inhibition effect is relieved by progesterone. Groups treated with 1 μM and 2 μM AG-205 showed decreased cell numbers and increased apoptosis rates in day 7 blastocysts compared to the control group. We also confirmed the recovery of inhibition by 100 nM progesterone. In conclusion, the present study indicated that progesterone positively affects the development of in vitro produced preimplantation porcine embryos by increasing cell proliferation and decreasing apoptosis via PGRMC1-involved actions. However, the detailed mechanisms of PGRMC1 need further elucidation.

Steroid hormones and pregnancy

Pregnancy is associated with physiological adjustments in order to allow adequate growth and fetal development. In particular, steroids are necessary to maintain in balance numerous functions during gestation. Steroidogenesis in the maternal, placental and fetal compartments and the biological effects of progestins and estrogens that play a pivotal role before and during pregnancy are described. Although it is well-known that androgens are considered as substrate for estrogens biosynthesis, their biosynthesis and functionality in placental and other tissues have been questioned. As compared with healthy pregnancy, steroid hormones levels have been found altered in complicated pregnancies and hormonal treatments have been used is some pathologies. Therefore, the aim of this work was to review the biosynthesis, function and regulation of progestins, androgens and estrogens during gestation. Furthermore, steroid hormones concentrations during healthy and complicated pregnancy as well hormonal therapies for the prevention of miscarriages and preterm deliveries are discussed in the present review.

The immunology of the macaque placenta: A detailed analysis and critical comparison with the human placenta

The cynomolgus monkey is increasingly considered in toxicological research as the most appropriate model for humans due to the species' close physiological contiguity, including reproductive physiology. Here, literature on the cynomolgus monkey placenta is reviewed in regards to its similarity to the human placenta and particularly for its immunological role, which is not entirely mirrored in humans. Pertinent original data are included in this article. The cynomolgus monkey placenta is evaluated based on three aspects: first, morphological development; second, the spatial and temporal appearance of maternal and fetal immune cells and certain immune cell products of the innate and adaptive immune systems; and third, the expression of relevant immune tolerance-related molecules including the homologs of anti-human leucocyte antigen, indoleamine 2,3-dioxygenase, FAS/FAS-L, annexin II, and progesterone. Parameters relevant to the immunological role of the placenta are evaluated from the immunologically immature stage of gestational day (GD) 50 until more mature stages close to birth. Selected comparisons are drawn with human and other laboratory animal placentas. In conclusion, the cynomolgus monkey placenta has a high degree of morphological and physiological similarity to the human placenta. However, there are differences in the topographical distribution of cell types and immune tolerance-related molecules. Three basic features are recognized: (1) the immunological capacity of the placenta changes throughout the lifetime of the organ; (2) these immunological changes include multiple parameters such as morphological adaptations, cell type involvement, and changes in immune-relevant molecule expression; and (3) the immune systems of two genetically disparate individuals (mother and child) are functionally intertwined at the maternal-fetal interface.

Progesterone effects on the oligodendrocyte linage: all roads lead to the progesterone receptor

A new role has emerged for progesterone after discovering its potent actions away from reproduction in both the central and the peripheral nervous system. The aim of the present report is to discuss progesterone’s mechanisms of action involved in myelination, remyelination and neuroinflammation. The pivotal role of the classic progesterone receptor is described and evidence is compiled about progesterone’s direct effects on oligodendrocyte linage and its indirect effects on oligodendrocyte precursor cell differentiation by decreasing the neuroinflammatory environment.

Absence of predictable long-term molecular effect of ulipristal acetate (UPA) on the endometrium

RESEARCH QUESTION

What are the effects of ulipristal acetate (UPA) on the expression of endometrial proliferation and maturation markers?

DESIGN

A total of 45 endometrium-containing blocks of hysterectomy samples from non-menopausal women with a diagnosis of moderate to severe symptoms of uterine fibroids: 14 women operated on at the end of a 3-month course of UPA; four women who had discontinued UPA treatment 1-12 months before surgery; 27 control unexposed samples (14 in the proliferative and 13 in the secretory phase). Immunohistochemical staining of Ki67, vascular endothelial growth factor-receptor 2 (VEGFR2), oestradiol receptor, progesterone receptor, interleukin-15 (IL-15), indoleamin-2,3-dioxygenase (IDO) and C-C motif chemokine ligand-2 (CCL2) markers were analysed in both endometrial compartments and layers.

RESULTS

Under UPA, oestradiol receptor and progesterone receptor expression is similar to the proliferative phase in both layers, although with a decrease in cell proliferation. IL-15, IDO and CCL2 expressions are similar to the proliferative phase, suggesting a progesterone-antagonist effect of UPA. VEGFR2 staining suggests a trend to a mixed agonist-antagonist effect. No significant difference is observed in the post-UPA proliferative phase group compared with the control group in both layers of the endometrium.

CONCLUSION

The effect of 3-month UPA treatment is mostly progesterone receptor antagonist-like. After treatment is discontinued, there are no signs of any long-term effects of this molecule on endometrial proliferation and maturation. Therefore, UPA may be administered to women willing to conceive in the short term without consequences for further implantation.

Characteristic Changes in Decidual Gene Expression Signature in Spontaneous Term Parturition

Background

The decidua has been implicated in the “terminal pathway” of human term parturition, which is characterized by the activation of pro-inflammatory pathways in gestational tissues. However, the transcriptomic changes in the decidua leading to terminal pathway activation have not been systematically explored. This study aimed to compare the decidual expression of developmental signaling and inflammation-related genes before and after spontaneous term labor in order to reveal their involvement in this process.

Methods

Chorioamniotic membranes were obtained from normal pregnant women who delivered at term with spontaneous labor (TIL, n = 14) or without labor (TNL, n = 15). Decidual cells were isolated from snap-frozen chorioamniotic membranes with laser microdissection. The expression of 46 genes involved in decidual development, sex steroid and prostaglandin signaling, as well as pro- and anti-inflammatory pathways, was analyzed using high-throughput quantitative real-time polymerase chain reaction (qRT-PCR). Chorioamniotic membrane sections were immunostained and then semi-quantified for five proteins, and immunoassays for three chemokines were performed on maternal plasma samples.

Results

The genes with the highest expression in the decidua at term gestation included insulin-like growth factor-binding protein 1 (IGFBP1), galectin-1 (LGALS1), and progestogen-associated endometrial protein (PAEP); the expression of estrogen receptor 1 (ESR1), homeobox A11 (HOXA11), interleukin 1β (IL1B), IL8, progesterone receptor membrane component 2 (PGRMC2), and prostaglandin E synthase (PTGES) was higher in TIL than in TNL cases; the expression of chemokine C-C motif ligand 2 (CCL2), CCL5, LGALS1, LGALS3, and PAEP was lower in TIL than in TNL cases; immunostaining confirmed qRT-PCR data for IL-8, CCL2, galectin-1, galectin-3, and PAEP; and no correlations between the decidual gene expression and the maternal plasma protein concentrations of CCL2, CCL5, and IL-8 were found.

Conclusions

Our data suggests that with the initiation of parturition, the decidual expression of anti-inflammatory mediators decreases, while the expression of pro-inflammatory mediators and steroid receptors increases. This shift may affect downstream signaling pathways that can lead to parturition.

Regulatory B Cells in Pregnancy: Lessons from Autoimmunity, Graft Tolerance, and Cancer

The success of pregnancy is contingent on the maternal immune system recognizing and accommodating a growing semi-allogeneic fetus. Specialized subsets of lymphocytes capable of negative regulation are fundamental in this process, and include the regulatory T cells (Tregs) and potentially, regulatory B cells (Bregs). Most of our current understanding of the immune regulatory role of Bregs comes from studies in the fields of autoimmunity, transplantation tolerance, and cancer biology. Bregs control autoimmune diseases and can elicit graft tolerance by inhibiting the differentiation of effector T cells and dendritic cells (DCs), and activating Tregs. Furthermore, in cancer, Bregs are hijacked by neoplastic cells to promote tumorigenesis. Pregnancy therefore represents a condition that reconciles these fields-mechanisms must be in place to ensure maternal immunological tolerance throughout gravidity to allow the semi-allogeneic fetus to grow within. Thus, the mechanisms underlying Breg activities in autoimmune diseases, transplantation tolerance, and cancer may take place during pregnancy as well. In this review, we discuss the potential role of Bregs as guardians of pregnancy and propose an endocrine-modulated feedback loop highlighting the Breg-Treg-tolerogenic DC interface essential for the induction of maternal immune tolerance.

Proliferative and Invasive Effects of Progesterone-Induced Blocking Factor in Human Glioblastoma Cells

Progesterone-induced blocking factor (PIBF) is a progesterone (P₄) regulated protein expressed in different types of high proliferative cells including astrocytomas, the most frequent and aggressive brain tumors. It has been shown that PIBF increases the number of human astrocytoma cells. In this work, we evaluated PIBF regulation by P₄ and the effects of PIBF on proliferation, migration, and invasion of U87 and U251 cells, both derived from human glioblastomas. PIBF mRNA expression was upregulated by P₄ (10 nM) from 12 to 24 h. Glioblastoma cells expressed two PIBF isoforms, 90 and 57 kDa. The content of the shorter isoform was increased by P₄ at 24 h, while progesterone receptor antagonist RU486 (10 μM) blocked this effect. PIBF (100 ng/mL) increased the number of U87 cells on days 4 and 5 of treatment and induced cell proliferation on day 4. Wound-healing assays showed that PIBF increased the migration of U87 (12–48 h) and U251 (24 and 48 h) cells. Transwell invasion assays showed that PIBF augmented the number of invasive cells in both cell lines at 24 h. These data suggest that PIBF promotes proliferation, migration, and invasion of human glioblastoma cells.

Expression and regulation of 11β-hydroxysteroid dehydrogenase type 1 in first trimester human decidua cells: Implication in preeclampsia

Glucocorticoids are implicated in successful blastocyst implantation, whereas alterations in glucocorticoid levels are associated with various pregnancy disorders including preeclampsia. Tissue concentration of active glucocorticoids depends on the expression of 11β-hydroxysteroid dehydrogenase (11β-HSD). This study investigated the contribution of first trimester decidua to glucocorticoid availability at the fetal-maternal interface by assessing the expression and regulation of 11β-HSD in human first trimester decidual tissues and cells and by evaluating 11β-HSD levels in preeclamptic vs. gestational age-matched decidua. 11β-HSD1 was the predominant isoform in first trimester decidua. In vitro, decidual cell 11β-HSD1 levels and enzymatic activity were up-regulated by ovarian steroids and inflammatory cytokines. Higher levels of 11β-HSD1 were found in preeclamptic decidua compared to controls. The present study indicates the predominance of 11β-HSD oxoreductase isoform in early decidua. Observations that ovarian hormones and inflammatory cytokines up-regulate 11β-HSD1, together with increased 11β-HSD1 expression in preeclampsia, highlight a role for decidual cells in controlling biologically active glucocorticoids in early pregnancy.

Number of parity and the risk of non-Hodgkin lymphomas: a dose-response meta-analysis of observational studies

BACKGROUND

Epidemiological reports have shown that parity is associated with a risk of developing non-Hodgkin lymphomas (NHL). However, the findings have been inconsistent.

METHODS

We searched the EMBASE and PubMed databases for eligible studies up to 10 March 2016. Category and generalized least square regression models were used to perform data analyses.

RESULTS

In total, five cohort and seven case-control studies were identified. Categorical analyses indicated that parity number has little association with NHL and its subtypes. In dose-risk analyses, there were no relationships between parity and NHL risk (p_{for association} = 0.064; n = 10). The summarized risk ratio (RR) was 0.97 (95% confidence interval (CI): 0.95-1.00; I² = 57.8%; p_{heterogeneity} = 0.014; Power = 0.79) for each additional live birth increase. Similarly, for B-cell NHL, there was a null association between parity and NHL risk (p_{for association} = 0.121; n = 5). The combined RR was 0.96 (95% CI = 0.90-1.03; I² = 63.7%; p_{heterogeneity} = 0.026; Power = 0.71) for each additional live birth. For follicular NHL, there was still a non-significant association identified (p_{for association} = 0.071; n = 4), the pooled RR was 1.00 (95% CI = 0.95-1.07; I² = 17.3%; p_{heterogeneity} = 0.305; Power = 0.26) per additional live birth.

CONCLUSIONS

Our data identified little evidence suggesting that high parity is a protective factor against the development of NHL, including its B-cell and follicular subtypes.

Effects of neonatal exposure to a glyphosate-based herbicide on female rat reproduction

In this study, we investigated whether neonatal exposure to a glyphosate-based herbicide (GBH) alters the reproductive performance and the molecular mechanisms involved in the decidualization process in adult rats. Newborn female rats received vehicle or 2 mg/kg/day of a GBH on postnatal days (PND) 1, 3, 5 and 7. On PND90, the rats were mated to evaluate (i) the reproductive performance on gestational day (GD) 19 and (ii) the ovarian steroid levels, uterine morphology, endometrial cell proliferation, apoptosis and cell cycle regulators, and endocrine pathways that regulate uterine decidualization (steroid receptors/COUP-TFII/Bmp2/Hoxa10) at the implantation sites (IS) on GD9. The GBH-exposed group showed a significant increase in the number of resorption sites on GD19, associated with an altered decidualization response. In fact, on GD9, the GBH-treated rats showed morphological changes at the IS, associated with a decreased expression of estrogen and progesterone receptors, a downregulation of COUP-TFII (Nr2f2) and Bmp2 mRNA and an increased expression of HOXA10 and the proliferation marker Ki67(Mki67) at the IS. We concluded that alterations in endometrial decidualization might be the mechanism of GBH-induced post-implantation embryo loss.

The Uterine Immune Profile May Help Women With Repeated Unexplained Embryo Implantation Failure After In Vitro Fertilization

LABELED PROBLEM

Embryo implantation remains the main limiting factor in assisted reproductive medicine (20% success rate).

METHODS OF STUDY

An endometrial immune profiling was performed among 394 women with the previous history of repeated embryo implantation failures (RIF). The endometrial immune profile documented the ratio of IL-15/Fn-14 mRNA as a biomarker of uNK cell activation/maturation (together with the uNK cell count) and the IL-18/TWEAK mRNA ratio as a biomarker of both angiogenesis and the Th1/Th2 balance. According to their profile, we recommended personalized care to counteract the documented dysregulation and assessed its effects by the live birth rate (LBR) for the next embryo transfer.

RESULTS

Endometrial immune profiles appeared to be dysregulated in 81.7% of the RIF patients compared to control. Overactivation was diagnosed in 56.6% and low activation in 25%. The LBR among these dysregulated/treated patients at the first subsequent embryo transfer was 39.8%.

CONCLUSION

Endometrial immune profiling may improve our understanding of RIF and subsequent LBR if treated.

Pregnancy and the Immune System: General Overview and the Gastroenterological Perspective

Pregnancy represents a unique immune tolerant condition that cannot be attributed merely to generalized immunosuppression. A variety of mechanisms have been described, ranging from the non-self recognition, immunomodulation of specific inflammatory cell populations and a Th2-directed shift of the immune response, which are mediated by both localized and systemic mediators. Furthermore, an inflammatory response directed toward the conceptus is no longer considered an obligatory deleterious response; instead, it is considered an important factor that is necessary for normal growth and development. These immunomodulatory changes during pregnancy may also affect concurrent conditions and alter the course of inflammatory diseases. Herein, we review the main immunomodulatory changes that occur during pregnancy and their effect on coexisting inflammatory conditions, with a specific focus on gastrointestinal disorders.

Chemokine CCL24 promotes the growth and invasiveness of trophoblasts through ERK1/2 and PI3K signaling pathways in human early pregnancy

Chemokine CCL24, acting through receptor CCR3, is a potent chemoattractant for eosinophil in allergic diseases and parasitic infections. We recently reported that CCL24 and CCR3 are co-expressed by trophoblasts in human early pregnant uterus. Here we prove with evidence that steroid hormones estradiol (E), progesterone (P), and human chorionic gonadotropin (hCG), as well as decidual stromal cells (DSCs) could regulate the expression of CCL24 and CCR3 of trophoblasts. We further investigate how trophoblast-derived CCL24 mediates the function of trophoblasts in vitro, and conclude that CCL24/CCR3 promotes the proliferation, viability and invasiveness of trophoblasts. In addition, analysis of the downstream signaling pathways of CCL24/CCR3 show that extracellular signal-regulated kinases (ERK1/2) and phosphoinositide 3-kinase (PI3K) pathways may contribute to the proliferation, viability and invasiveness of trophoblasts by activating intracellular molecules Ki67 and matrix metallopeptidase 9 (MMP9). However, we did not observe any inhibitory effect on trophoblasts when blocking c-Jun N-terminal kinase (JNK) or p38 pathways. In conclusion, our data suggests that trophoblast-derived CCL24 at the maternal-fetal interface promotes trophoblasts cell growth and invasiveness by ERK1/2 and PI3K pathways. Meanwhile, pregnancy-related hormones (P and hCG), as well as DSCs could up-regulate CCL24/CCR3 expression in trophoblasts, which may indirectly influence the biological functions of trophoblasts. Thus, our results provide a possible explanation for the growth and invasion of trophoblasts in human embryo implantation.

Association of 17α-Hydroxyprogesterone Caproate and Risk of Infection

OBJECTIVE

To evaluate whether exposure to 17α-hydroxyprogesterone caproate is associated with the rate of peripartum infection in women who deliver preterm and their neonates.

METHODS

This is a retrospective cohort study of patients who delivered before 37 weeks of gestation at a tertiary care hospital between July 1, 2005, and December 31, 2012. Women in the case group (women exposed to 17α-hydroxyprogesterone caproate) were matched to women in a control group (unexposed patients) by gestational age and delivery date. The primary outcome was a composite infection rate comprising histologic or clinical chorioamnionitis, endometritis, or early-onset neonatal sepsis. To detect a 15% difference in composite infection rate between women exposed to 17α-hydroxyprogesterone caproate and those unexposed (two-tailed α=0.05 and power=80%), 183 patients per group were required. Logistic regression was performed to control for a history of prior spontaneous preterm birth and exposure to betamethasone.

RESULTS

The primary outcome frequency for women exposed to 17α-hydroxyprogesterone caproate was 34.6% (64 patients) compared with 33% (61 patients) in those unexposed (P=.74). There was no significant difference between women exposed to 17α-hydroxyprogesterone caproate and those unexposed in frequency of clinical chorioamnionitis (1.9% compared with 1.1%, P=.66), histologic chorioamnionitis (39.4% compared with 40%, P=.92), or early-onset neonatal sepsis (2.7% compared with 1.1%, P=.28). A total of 7.1% of women exposed to 17α-hydroxyprogesterone caproate developed endometritis compared with 2.7% of those unexposed (P=.05). The adjusted odds ratio for the primary outcome in women exposed to 17α-hydroxyprogesterone caproate was 0.65 (95% confidence interval 0.31-1.38).

CONCLUSION

Exposure to 17α-hydroxyprogesterone caproate does not increase the risk of peripartum infection among women who deliver preterm or their neonates.

LEVEL OF EVIDENCE

II.

Placental claudin expression and its regulation by endogenous sex steroid hormones

Tight junctions (TJs) form continuous intercellular contacts controlling the paracellular transportation across the cell-to-cell junction. TJ components include the peripheral protein zonula occludens-1 (ZO-1), junctional adhesion molecules (JAMs), and integral proteins such as occludin and claudins. Among the junction proteins, claudins play a major role in regulation of paracellular electrolyte transportation. This study explores the expression and distribution of tight junctions and their regulation during pregnancy. To study the regulation of claudin family, we examined expression of mouse placental tight junction proteins, including claudin-1 to -24, with real-time PCR and Western blotting and distribution of tight junction proteins with immunohistochemistry. Pregnant C57/BL6 mice were used in this study. The pregnant mice were divided into three groups depending on pregnant day (on days 12, 16, and 20 of gestation). Regarding the transcription levels, claudin-1, claudin-2, claudin-4, and claudin-5 expression levels were relatively high compared to other claudin family in all periods of pregnancy. Claudin-4 and 5 expressions, which reduce ion permeability, were increased over a period of time. However, claudin-2 expression, that is the responsive protein for a decrease in paracellular conductance, was decreased. Following this modulation of expression during mid-term pregnancy, we identified endogenous hormonal modulation of claudin family using estrogen receptor antagonist ICI 182,780 and progesterone receptor antagonist RU-486. After administration of ICI and RU-486, expression of claudin-4 mRNA and protein was increased. In addition, immunohistochemistry was performed to identify their localization for inferring permeability in placenta. Due to the function of claudins as effectors of ion transport at the end of regulatory pathways, they must be transducing proteins that modulate the function of claudins and thus link the physiologic inputs to the final effectors. This study will provide the claudin expressions and their localization in the mouse placenta, and their regulation by endogenous hormones. Taken together, the results of this study may contribute to assuming the roles and regulatory mechanism of these tight junction genes regarding maternal-fetal ion transportation in the placenta.

Unstable Foxp3+ regulatory T cells and altered dendritic cells are associated with lipopolysaccharide-induced fetal loss in pregnant interleukin 10-deficient mice

Maternal interleukin (IL) 10 deficiency elevates susceptibility to fetal loss induced by the model Toll-like receptor agonist lipopolysaccharide, but the mechanisms are not well elucidated. Here, we show that Il10 null mutant (Il10(-/-)) mice exhibit altered local T cell responses in pregnancy, exhibiting pronounced hyperplasia in para-aortic lymph nodes draining the uterus with >6-fold increased CD4(+) and CD8(+) T cells compared with wild-type controls. Among these CD4(+) cells, Foxp3(+) T regulatory (Treg) cells were substantially enriched, with 11-fold higher numbers at Day 9.5 postcoitum. Lymph node hypertrophy in Il10(-/-) mice was associated with more activated phenotypes in dendritic cells and macrophages, with elevated expression of MHCII, scavenger receptor, and CD80. Affymetrix microarray revealed an altered transcriptional profile in Treg cells from pregnant Il10(-/-) mice, with elevated expression of Ctse (cathepsin E), Il1r1, Il12rb2, and Ifng. In vitro, Il10(-/-) Treg cells showed reduced steady-state Foxp3 expression, and polyclonal stimulation caused greater loss of Foxp3 and reduced capacity to suppress IL17 in CD4(+)Foxp3(-) T cells. We conclude that despite a substantially expanded Treg cell pool, the diminished stability of Treg cells, increased numbers of effector T cells, and altered phenotypes in dendritic cells and macrophages in pregnancy all potentially confer vulnerability to inflammation-induced fetal loss in Il10(-/-) mice. These findings suggest that IL10 has a pivotal role in facilitating robust immune protection of the fetus from inflammatory challenge and that IL10 deficiency could contribute to human gestational disorders in which altered T cell responses are implicated.

HLA-G Orchestrates the Early Interaction of Human Trophoblasts with the Maternal Niche

Extravillous trophoblasts (EVTs) play a central role in educating maternal leukocytes, endometrial stromal and endothelial cells to generate a receptive decidual microenvironment tailored to accept the semi-allogeneic fetus. HLA-G, a non-classical HLA class I molecule endowed with immune-regulatory functions, is primarily expressed on EVTs lining the placenta and on the naturally occurring tolerogenic dendritic cells, named DC-10, which are enriched in the human first trimester decidua. Decidual DC-10 are involved in HLA-G-mediated tolerance at the maternal–fetal interface. EVTs not only establish a tolerogenic microenvironment through the interaction with maternal innate and adaptive cells but also orchestrate placenta vascular and tissue remodeling, leading to a successful pregnancy. Here, we discuss the potential implications of the HLA-G-mediated cross-talk among the cells present at the maternal–fetal interface, and its role in maintaining a positive relationship between the mother and the fetus.

Sirh7/Ldoc1 knockout mice exhibit placental P4 overproduction and delayed parturition

Sirh7/Ldoc1 [sushi-ichi retrotransposon homolog 7/leucine zipper, downregulated in cancer 1, also called mammalian retrotransposon-derived 7 (Mart7)] is one of the newly acquired genes from LTR retrotransposons in eutherian mammals. Interestingly, Sirh7/Ldoc1 knockout (KO) mice exhibited abnormal placental cell differentiation/maturation, leading to an overproduction of placental progesterone (P4) and placental lactogen 1 (PL1) from trophoblast giant cells (TGCs). The placenta is an organ that is essential for mammalian viviparity and plays a major endocrinological role during pregnancy in addition to providing nutrients and oxygen to the fetus. P4 is an essential hormone in the preparation and maintenance of pregnancy and the determination of the timing of parturition in mammals; however, the biological significance of placental P4 in rodents is not properly recognized. Here, we demonstrate that mouse placentas do produce P4 in mid-gestation, coincident with a temporal reduction in ovarian P4, suggesting that it plays a role in the protection of the conceptuses specifically in this period. Pregnant Sirh7/Ldoc1 knockout females also displayed delayed parturition associated with a low pup weaning rate. All these results suggest that Sirh7/Ldoc1 has undergone positive selection during eutherian evolution as a eutherian-specific acquired gene because it impacts reproductive fitness via the regulation of placental endocrine function.

Progesterone-induced activation of membrane-bound progesterone receptors in murine macrophage cells

Parturition is an inflammatory process mediated to a significant extent by macrophages. Progesterone (P4) maintains uterine quiescence in pregnancy, and a proposed functional withdrawal of P4 classically regulated by nuclear progesterone receptors (nPRs) leads to labor. P4 can affect the functions of macrophages despite the reported lack of expression of nPRs in these immune cells. Therefore, in this study we investigated the effects of the activation of the putative membrane-associated PR on the function of macrophages (a key cell for parturition) and discuss the implications of these findings for pregnancy and parturition. In murine macrophage cells (RAW 264.7), activation of mPRs by P4 modified to be active only extracellularly by conjugation to BSA (P4BSA, 1.0×10(-7) mol/l) caused a pro-inflammatory shift in the mRNA expression profile, with significant upregulation of the expression of cyclooxygenase 2 (COX2 (Ptgs2)), Il1B, and Tnf and downregulation of membrane progesterone receptor alpha (Paqr7) and oxytocin receptor (Oxtr). Pretreatment with PD98059, a MEK1/2 inhibitor, significantly reduced P4BSA-induced expression of mRNA of Il1B, Tnf, and Ptgs2. Inhibition of protein kinase A (PKA) by H89 blocked P4BSA-induced expression of Il1B and Tnf mRNA. P4BSA induced rapid phosphorylation of MEK1/2 and CREB (a downstream target of PKA). This phosphorylation was inhibited by pretreatment with PD98059 and H89, respectively, revealing that MEK1/2 and PKA are two of the components involved in mPR signaling. Taken together, these results indicate that changes in membrane progesterone receptor alpha expression and signaling in macrophages are associated with the inflammatory responses; and that these changes might contribute to the functional withdrawal of P4 related to labor.

Myeloid decidual dendritic cells and immunoregulation of pregnancy: defective responsiveness to Coxiella burnetii and Brucella abortus

Dendritic cells (DCs) are a component of the placental immune system, but their role in pregnancy is still poorly understood. Decidual DCs (dDCs) were selected from at-term pregnancy on the basis of CD14 and CD11c expression. A phenotypic analysis revealed that dDCs are characterized by the expression of monocyte-derived DC (moDCs) markers and specific markers such as HLA-G and its ligand ILT4. As demonstrated by whole-genome microarray, dDCs expressed a specific gene program markedly distinct from that of moDCs; it included estrogen- and progesterone-regulated genes and genes encoding immunoregulatory cytokines, which is consistent with the context of foeto-maternal tolerance. A functional analysis of dDCs showed that they were unable to mature in response to bacterial ligands such as lipopolysaccharide or peptidoglycan, as assessed by the expression of HLA-DR, CD80, CD83, and CD86. When dDCs were incubated with bacteria known for their placenta tropism, Coxiella burnetii and Brucella abortus, they were also unable to mature and to produce inflammatory cytokines. It is likely that the defective maturation of dDCs and their inability to produce inflammatory cytokines is related to the spontaneous release of IL-10 by these cells. Taken together, these results suggest that dDCs exhibit an immunoregulatory program, which may favor the pathogenicity of C. burnetii or B. abortus.

Suppression of aldosterone and progesterone in preeclampsia

OBJECTIVE

Preeclampsia (preE) is a hypertensive disorder seen in 3-10% of human pregnancies and is diagnosed by de novo onset of hypertension and proteinuria. Several research groups provided evidence for reduced aldosterone (Aldo) and progesterone (Prog) availability in preE. The aim of this study was to determine the levels of Aldo and Prog in preE.

METHODS

Normal pregnant (NP; n = 39) and preE (n = 30) patients were recruited to have their blood drawn between 21 and 40 weeks of pregnancy. Two groups of rats were used in this study: NP rats (n = 10) and preE rats (n = 10), which were given weekly injections of desoxycorticosterone acetate and 0.9% saline to drink. Aldo and Prog levels were assayed in plasma and urine samples by ELISA kits.

RESULTS

In preE patients, the mean Aldo and Prog levels were suppressed (p < 0.05) compared to NP patients. NP patients exhibited a trend of increased levels of Aldo with an increase in gestational age; however, preE patients had the opposite trend. Both normal and preE patients exhibited a trend of increased levels of Prog with an increase in gestational age. The plasma and urinary Aldo and Prog levels were lower (p < 0.05) in preE rats compared to NP rats.

CONCLUSIONS

We have demonstrated using a rat model and patients that both Aldo and Prog are suppressed in preE and thus may be used as biomarkers for preE.