Steroids as immunosuppressants in pregnancy

Non-Infectious Uveitis and Pregnancy, is There an Optimal Treatment? Uveitis Course and Safety of Uveitis Treatment in Pregnancy

In pregnancy, a plethora of factors causes changes in maternal immunity. Uveitis flare-ups are more frequent in the first trimester and in undertreated patients. Management of non-infectious uveitis during pregnancy remains understudied. A bibliographic review to consolidate existing evidence was performed by a multidisciplinary group of Ophthalmologists, Gynaecologists and Rheumatologists. Our group recommends initial management with minimum-required doses of corticosteroids, preferably locally, to treat intraocular inflammation whilst ensuring good neonatal outcomes. If ineffective, clinicians should consider addition of Cyclosporine, Azathioprine or Certolizumab pegol, which are seemingly safe in pregnancy. Other therapies (such as Methotrexate, Mycophenolate Mofetil and alkylating agents) are teratogenic or have a detrimental effect on the foetus. Furthermore, careful multidisciplinary preconception discussions and close follow-up are recommended, monitoring for flare-ups and actively tapering medication doses, with a primary endpoint focused on protecting ocular tissues from inflammation, whilst giving minimal risk of poor pregnancy and foetal outcomes.

The hormonal control of parturition

Parturition is a complex physiological process that must occur in a reliable manner and at an appropriate gestation stage to ensure a healthy newborn and mother. To this end, hormones that affect the function of the gravid uterus, especially progesterone (P4), 17β-estradiol (E2), oxytocin (OT), and prostaglandins (PGs), play pivotal roles. P4 via the nuclear P4 receptor (PR) promotes uterine quiescence and for most of pregnancy exerts a dominant block to labor. Loss of the P4 block to parturition in association with a gain in prolabor actions of E2 are key transitions in the hormonal cascade leading to parturition. P4 withdrawal can occur through various mechanisms depending on species and physiological context. Parturition in most species involves inflammation within the uterine tissues and especially at the maternal-fetal interface. Local PGs and other inflammatory mediators may initiate parturition by inducing P4 withdrawal. Withdrawal of the P4 block is coordinated with increased E2 actions to enhance uterotonic signals mediated by OT and PGs to promote uterine contractions, cervix softening, and membrane rupture, i.e., labor. This review examines recent advances in research to understand the hormonal control of parturition, with focus on the roles of P4, E2, PGs, OT, inflammatory cytokines, and placental peptide hormones together with evolutionary biology of and implications for clinical management of human parturition.

The Role of the Placental Enzyme Indoleamine 2,3-Dioxygenase in Normal and Abnormal Human Pregnancy

The biologically significant phenomenon that the fetus can survive immune attacks from the mother has been demonstrated in mammals. The survival mechanism depends on the fetus and placenta actively defending themselves against attacks by maternal T cells, achieved through the localized depletion of the amino acid L-tryptophan by an enzyme called indoleamine 2,3-dioxygenase. These findings were entirely unexpected and pose important questions regarding diseases related to human pregnancy and their prevention during human pregnancy. Specifically, the role of this mechanism, as discovered in mice, in humans remains unknown, as does the extent to which impaired activation of this process contributes to major clinical diseases in humans. We have, thus, elucidated several key aspects of this enzyme expressed in the human placenta both in normal and abnormal human pregnancy. The questions addressed in this brief review are as follows: (1) localization and characteristics of human placental indoleamine 2,3-dioxygenas; (2) overall tryptophan catabolism in human pregnancy and a comparison of indoleamine 2,3-dioxygenase expression levels between normal and pre-eclamptic pregnancy; (3) controlling trophoblast invasion by indoleamine 2,3-dioxygenase and its relation to the pathogenesis of placenta accrete spectrum.

Developmental programming: Impact of preconceptional and gestational exposure to a real-life environmental chemical mixture on maternal steroid, cytokine and oxidative stress milieus in sheep

BACKGROUND

Gestational exposure to environmental chemicals (ECs) is associated with adverse, sex-specific offspring health effects of global concern. As the maternal steroid, cytokine and oxidative stress milieus can have critical effects on pregnancy outcomes and the programming of diseases in offspring, it is important to study the impact of real-life EC exposure, i.e., chronic low levels of mixtures of ECs on these milieus. Sheep exposed to biosolids, derived from human waste, is an impactful model representing the ECs humans are exposed to in real-life. Offspring of sheep grazed on biosolids-treated pasture are characterized by reproductive and metabolic disruptions.

OBJECTIVE

To determine if biosolids exposure disrupts the maternal steroid, cytokine and oxidative stress milieus, in a fetal sex-specific manner.

METHODS

Ewes were maintained before mating and through gestation on pastures fertilized with biosolids (BTP), or inorganic fertilizer (Control). From maternal plasma collected mid-gestation, 19 steroids, 14 cytokines, 6 oxidative stress markers were quantified. Unpaired t-test and ANOVA were used to test for differences between control and BTP groups (n = 15/group) and between groups based on fetal sex, respectively. Correlation between the different markers was assessed by Spearman correlation.

RESULTS

Concentrations of the mineralocorticoids - deoxycorticosterone, corticosterone, the glucocorticoids - deoxycortisol, cortisol, cortisone, the sex steroids - androstenedione, dehydroepiandrosterone, 16-OH-progesterone and reactive oxygen metabolites were higher in the BTP ewes compared to Controls, while the proinflammatory cytokines IL-1β and IL-17A and anti-inflammatory IL-36RA were decreased in the BTP group. BTP ewes with a female fetus had lower levels of IP-10.

DISCUSSION

These findings suggest that pre-conceptional and gestational exposure to ECs in biosolids increases steroids, reactive oxygen metabolites and disrupts cytokines in maternal circulation, likely contributors to the aberrant phenotypic outcomes seen in offspring of BTP sheep - a translationally relevant precocial model.

The rapid activation of cPKCβII by progesterone results in the negative regulation of Ca 2+ influx in human resting T cells

BACKGROUND

Progesterone-stimulated rapid suppression of phytohemagglutinin (PHA)-activated sustained membrane Ca 2+ influx is revealed by Mn 2+ quenching fura-2 fluorescence. Ca 2+ influx suppression results in immunosuppression of T-cell proliferation. Downregulation of protein kinase C (PKC) activity by phorbol 12-myristate 13-acetate (PMA) enhances the PHA-activated increase in sustained intracellular Ca 2+ concentration ([Ca 2+ ] i ) via Ca 2+ influx in T cells. Conventional PKC (cPKC) inhibitors also enhance the [Ca 2+ ] i increase in resting T cells caused by progesterone. This study explores whether cPKC activation by progesterone results in suppression of Ca 2+ influx in resting T cells.

METHODS

Progesterone, its analogs (R5020/Org OD 02-0), and plasma membrane-impermeable progesterone-bovine serum albumin conjugate were used to stimulate human resting T cells. Inhibitors and PKC downregulation by PMA were used to investigate whether cPKC affects Ca 2+ influx.

RESULTS

Progesterone and analogs dose-dependently suppressed Ca 2+ influx in T cells. One cPKC inhibitor, Ro318220, attenuated Ca 2+ influx suppression, and enhanced the increase in [Ca 2+ ] i caused by progesterone and analogs. U73122 did not affect Ca 2+ influx suppression but did decrease the [Ca 2+ ] i increase. Ca 2+ influx suppression was not attenuated by the cPKCα/βI isoform-selective inhibitor, Go6976, nevertheless, a cPKCβI/βII isoform-selective inhibitor, LY333531 did. Ca 2+ influx suppression was attenuated by the cPKCβII-specific inhibitor CGP53353. After PKC downregulated by PMA, Ca 2+ influx suppression by progesterone and analogs was almost abolished in parallel with a massive reduction in cPKCβII expression. This suggests cPKCβII activation by progesterone and analogs mediate Ca 2+ influx suppression in resting T cells.

CONCLUSION

Nongenomic membrane activation of cPKCβII by progesterone causes immunosuppression via negative regulation of Ca 2+ influx into human resting T cells. This prevents resting T-cell activation and proliferation, which protects the fetus from maternal immune attack while decreasing maternal autoimmune disease flare-ups during pregnancy. Thus, cPKCβII modulators might provide a new therapeutic approach to balancing T-cell tolerance and immunity.

Signaling Pathways Regulating Human Cervical Ripening in Preterm and Term Delivery

At the end of gestation, the cervical tissue changes profoundly. As a result of these changes, the uterine cervix becomes soft and vulnerable to dilation. The process occurring in the cervical tissue can be described as cervical ripening. The ripening is a process derivative of enzymatic breakdown and inflammatory response. Therefore, it is apparent that cervical remodeling is a derivative of the reactions mediated by multiple factors such as hormones, prostaglandins, nitric oxide, and inflammatory cytokines. However, despite the research carried out over the years, the cellular pathways responsible for regulating this process are still poorly understood. A comprehensive understanding of the entire process of cervical ripening seems crucial in the context of labor induction. Greater knowledge could provide us with the means to help women who suffer from dysfunctional labor. The overall objective of this review is to present the current understanding of cervical ripening in terms of molecular regulation and cell signaling.

High-progesterone environment preserves T cell competency by evading glucocorticoid effects on immune regulation

Progesterone (P4) and glucocorticoid (GC) play crucial roles in the immunoregulation of a mother to accept and maintain a semi-allogenic fetus. P4 concentration increases during pregnancy and becomes much higher in the placenta than in the other peripheral tissues, wherein the concentration of cortisol (COR), the most abundant GC and a strong immunosuppressor, remains uniform throughout the rest of the body. Here, we evaluated the effect of a high-P4 environment on pregnant immunity by comparing it with COR. Naïve T cell proportion increased transiently in peripheral blood of pregnant women just after delivery and decreased after one month. T cells stimulated with superantigen toxic-shock-syndrome-1 (TSST-1) in the presence of P4 stayed in the naïve state and did not increase, irrespective of the presence of COR, and reactive T cells could not survive. Treatment of T cells with P4 without T cell receptor (TCR) stimulation transiently suppressed T cell activation and proliferation, whereas the levels remain unaltered if P4 was not given before stimulation. Comparison of the engraftment and response against specific antigens using hu-PBL-NOG-hIL-4-Tg mice showed that P4-pretreated lymphocytes preserved CD62L expression and engrafted effectively in the spleen. Moreover, they produced antigen-specific antibodies, whereas COR-pretreated lymphocytes did not. These results suggest that a high-P4 environment suppresses T cell activation and induces T cell migration into lymphoid tissues, where they maintain the ability to produce anti-pathogen antibodies, whereas COR does not preserve T cell function. The mechanism may be pivotal in maintaining non-fetus-specific T cell function in pregnancy.

Transcriptomic analysis reveals the effects of maternal selenium deficiency on placental transport, hormone synthesis, and immune response in mice

Selenium deficiency has been considered to increase the risk of gestational complications. Our previous work showed that maternal selenium deficiency suppressed proliferation, induced autophagy dysfunction and apoptosis in the placenta of mice. However, other effects of maternal selenium deficiency on the placenta and the underlying mechanisms remain unclear. In the present study, dietary selenium deficiency in dams significantly suppressed glutathione peroxidase (GSH-Px) activity, total antioxidant capacity (T-AOC), and increased malondialdehyde (MDA) content in the placentae, confirming the oxidative stress in the placenta. By transcriptome sequencing analysis, the DEGs were involved in many biological processes, including ion transport, lipid metabolic process, immune response, transmembrane transport, and others. According to the KEGG analysis, the DEGs were primarily enriched in metabolic pathways, PI3K-Akt signaling pathway, and others. Among these, the steroid hormone biosynthesis pathway enriched the most DEGs. Hsd3b1, an ER enzyme involved in progesterone synthesis, was validated downregulated. Consistently, the progesterone content in the serum of the selenium-deficient group was decreased. Ion transporters and transmembrane transporters, such as Heph, Trf, Slc39a8, Slc23a1, Atp7b, and Kcnc1, were reduced in the selenium-deficient placentae. Immune response-related genes, including Ccl3, Ccl8, Cxcl10, and Cxcl14, were increased in the selenium-deficient placentae, along with an increase in macrophage number. These results suggested that maternal selenium deficiency may impair progesterone biosynthesis, reduce nutrient transporters expression, and promote immune response by increasing the oxidative stress of the placentae. This present study provides a novel insight into the possible cause of placenta disorder during 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.

Effect of 2,6-xylidine (DMA) on secretion of biomarkers for inflammation and neurodevelopment by the placenta

Cigarette smoke enhances placental inflammation and interferes with steroidogenesis. However, the chemicals in the smoke responsible for these biological activities are unclear. 2,6 xylidine (also called 2,6 Dimethylaniline, DMA) is a component of cigarette smoke that has carcinogenic properties but its effects on the placenta are unknown. Therefore, we hypothesized that DMA may interfere with placental steroidogenesis or enhance placental inflammation. Placental explant cultures were treated with 0-50,000 nM DMA and concentrations of progesterone (P₄), estradiol (E₂), testosterone (T), IL-1β, TNF-α, IL-6, sgp130, HO-1, IL-10, 8-Isoprostane (8-IsoP), and BDNF in the conditioned medium were quantified. Since many environmental toxins enhance the proinflammatory host response to infection, we also performed experiments on placental cultures co-stimulated with 10⁷ heat-killed E. coli. DMA alone significantly reduced P₄ and T secretion but enhanced E₂ secretion. The toxin also reduced placental secretion of IL-6, sgp130, and BDNF. For bacteria-stimulated cultures, DMA increased secretion of P₄ and T, and proinflammatory cytokines (IL-1β, TNF-α) but had mixed effects on anti-inflammatory markers, increasing some (sgp130, IL-10) and reducing others (HO-1). However, DMA enhanced 8-IsoP levels by bacteria-stimulated placental cultures, suggesting that it increases oxidative stress by the tissues. These studies suggest that DMA affects secretion of biomarkers by the placenta and may promote inflammation. Further studies are needed to determine if these observed changes occur in vivo and the extent to which DMA exposure increases the risk of adverse pregnancy outcomes associated with smoking in pregnancy.

Progesterone decreased indoleamine 2,3-dioxygenase 1(IDO1) expression in early pregnancy chorionic villi and decidua

Indoleamine 2,3-dioxygenase1(IDO1) is one of the most important proteins in protect the embryos from the mother's immune system during pregnancy. However, the regulation of the protein expression at the maternal-foetal interface is not fully known. We aimed to study the regulation of IDO1 expression by progesterone in villi and decidua of in early pregnancy. Fifty cases of early pregnancy women's villi and decidua were collected. Tissue explants of chorionic villi and the decidua were cultured in media containing in different concentrations of progesterone, in the presence or absence of mifepristone. Western blot analysis and immunofluorescence were used to detect the expression of IDO1 in chorionic villi and decidua in cultured tissues. IDO1 protein was identified in chorionic villi and decidua tissues of normal pregnant women, and the expression of IDO1in the decidua was significantly higher than those in chorionic villi. Progesterone decreased IDO1 expression in early pregnancy chorionic villi and decidua, and mifepristone, as the progesterone inhibitor, reverted this effect. In normal physiological state of pregnancy, progesterone may be involved in the regulation of immune tolerance by negative regulation of IDO1 expression at maternal foetal interface. Progesterone may down-regulate IDO1 expression during early pregnancy.

Sexual maturity, seasonal estrus, and gestation in female Indo-Pacific bottlenose dolphins Tursiops aduncus inferred from serum reproductive hormones

Reproductive hormones in serum concentrations of progesterone, estradiol, and testosterone in female Indo-Pacific bottlenose dolphins (Tursiops aduncus, n = 12) housed in Ocean Park Hong Kong were investigated in the present study. Results showed that, onset of puberty of captive Indo-Pacific bottlenose dolphins was at 5 years while sexual maturity was at 6. Average serum progesterone concentrations in non-pregnant sexually mature individuals was 0.33 (0.25-0.97) ng/mL (interquartile), significantly higher than in immature ones 0.26 (0.25-0.38) ng/mL. This study found significant difference in serum estradiol concentrations between individuals at the onset of puberty (9.5 ± 1.7 pg/mL, ±SD) and not (below detection limit 9 pg/mL). A slightly seasonal breeding pattern, with progesterone values tend to be higher from February to October (0.38 [0.25-1.07] ng/mL) was inferred. During pregnancy, serum progesterone concentrations range from 10.54 ± 8.74 ng/mL (indexed month post-conception [IMPC] 0) to 25.49 ± 12.06 ng/mL (IMPC 2), and display a bimodal pattern with 2 peaks in early- (25.49 ± 12.06 ng/mL, IMPC 2) and late-pregnancy (21.71 ± 10.25 ng/mL, IMPC 12), respectively. Serum estradiol concentrations can seldom be detected in early-pregnancy and increase constantly in mid- (9.45 ± 1.83 pg/mL) and late-pregnancy (11.88 ± 3.81 pg/mL), with a spike (15.45 ± 6.78 pg/mL) 1 month prior to delivery. Serum testosterone concentrations elevate significantly in IMPC 7 (0.36 ± 0.10 ng/mL) compared to other months (0.16 ± 0.10 ng/mL) of the year. The present study provides normal concentration profiles for some reproductive hormones in female Indo-Pacific bottlenose dolphins and can contribute to the breeding monitoring of this species. Also, our study would shed further light on the reproductive physiology of small cetaceans.

Improved filtration method to isolate pure populations of primary bovine endometrial epithelial and stromal cells for immunological studies

Objectives

Isolation and culture of distinct primary endometrial cells are key to reliable in-vitro models to investigate the uterine immune response and optimse new disease interventions. Details on the isolation method and purity of distinct cell populations is lacking in currently available protocols leading to inconsistent results across laboratories.

Methods

Bovine endometrial tissue from non-pregnant bovine uteri were collected immediately post-mortem and separated using differential size filtering. Isolations (n = 15) yielded an average of 3.1 × 10⁵ ± 0.7 × 10⁵ epithelial cells and 1.88 × 10⁶ ± 5.44 × 10⁵ stromal fibroblasts per uterine horn. Following expansion in culture, the purity of cell populations was confirmed using morphology and positive staining for cytokeratin and vimentin which identifies epithelial and stromal fibroblast populations, respectively. Using PCR, cDNA from both cell populations was negative for CD45, a marker of immune cells.

Results

On challenge with a bacterial PAMP (LPS), epithelial and stromal fibroblasts showed a marked increase in the expression of the inflammatory mediators IL8, IL6, S100A8 and S100A9, with both cell populations displaying distinct expression profiles. Here we provide a detailed methodology on the culture of primary bovine endometrial epithelial and stromal cells and demonstrate these cells provide a physiologically relevant model for studies of endometrial inflammation and its regulation.

Electronic supplementary material

The online version of this article (10.1007/s11259-020-09770-3) contains supplementary material, which is available to authorized users.

Ovulation: Parallels With Inflammatory Processes

The midcycle surge of LH sets in motion interconnected networks of signaling cascades to bring about rupture of the follicle and release of the oocyte during ovulation. Many mediators of these LH-induced signaling cascades are associated with inflammation, leading to the postulate that ovulation is similar to an inflammatory response. First responders to the LH surge are granulosa and theca cells, which produce steroids, prostaglandins, chemokines, and cytokines, which are also mediators of inflammatory processes. These mediators, in turn, activate both nonimmune ovarian cells as well as resident immune cells within the ovary; additional immune cells are also attracted to the ovary. Collectively, these cells regulate proteolytic pathways to reorganize the follicular stroma, disrupt the granulosa cell basal lamina, and facilitate invasion of vascular endothelial cells. LH-induced mediators initiate cumulus expansion and cumulus oocyte complex detachment, whereas the follicular apex undergoes extensive extracellular matrix remodeling and a loss of the surface epithelium. The remainder of the follicle undergoes rapid angiogenesis and functional differentiation of granulosa and theca cells. Ultimately, these functional and structural changes culminate in follicular rupture and oocyte release. Throughout the ovulatory process, the importance of inflammatory responses is highlighted by the commonalities and similarities between many of these events associated with ovulation and inflammation. However, ovulation includes processes that are distinct from inflammation, such as regulation of steroid action, oocyte maturation, and the eventual release of the oocyte. This review focuses on the commonalities between inflammatory responses and the process of ovulation.

Drug nanocrystals: Fabrication methods and promising therapeutic applications

The drug nanocrystals (NCs) with unique physicochemical properties are now considered as a promising drug delivery system for poorly water-soluble drugs. So far >20 formulations of NCs have been approved in the market. In this review, we summarized recent advances of NCs with emphasis on their therapeutic applications based on administration route and disease states. At the end, we present a brief description of the future perspectives of NCs and their potential role as a promising drug delivery system. As a strategy for solubilization and bioavailability enhancement, the NCs have gained significant success. Besides this, the function of NCs is still far from developed. The emerging NC-based drug delivery approach would widen the applications of NCs in drug delivery and bio-medical field. Their in vitro and in vivo fate is extremely unclear; and the development of hybrid NCs with environment-sensitive fluorophores may assist to extend the scope of bio-imaging and provide better insight to their intracellular uptake kinetics, in vitro and in vivo.

Preparation and Evaluation of Progesterone Nanocrystals to Decrease Muscle Irritation and Improve Bioavailability

Progesterone (PG) is a crucial immunomodulatory agent during early pregnancy, and nowadays PG oil-based injection (PG/OI) has a huge market all over the world. However, PG/OI may accumulate the local muscle and further cause irritations after long-term administration. In this study, PG nanocrystals (PG/NCs) injection was developed to decrease muscle toxicity. PG/NCs injection containing 10% (w/v) PG was first prepared using a wet grinding method. Then, particle size, zeta potential, morphology powder, X-ray diffraction (PXRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) studies were carried out to evaluate the characteristics of dosage form. The rabbit muscle irritation, hemolysis, and rat pharmacokinetics tests were used to estimate the in vivo characteristics of PG/NCs. The results showed that the mean particle size and the zeta potentials of NCs were 299.5 ± 9.0 nm and - 36.8 ± 1.5 mV, respectively. The crystalline state of PG/NCs was not altered during particle size reduction according to PXRD, DSC, and FTIR results. Muscle irritation presented that PG/NCs had lower irritation than that of PG/OI. Hemolysis test suggested that PG/NCs injection was functioned without hemolysis and red cell agglutination. The pharmacokinetics study showed that the AUC_0-t and C_max of PG/NCs was 3.2-fold (p < 0.05) and 3.1-fold higher than PG/OI, which demonstrated that PG/NCs injection had greater bioavailability than PG/OI. Therefore, it was obvious that PG/NCs injection exhibited a lower muscle irritation, hemolysis rate, and higher bioavailability, which was a better dosage form than OI.

Vaginal progesterone for preventing preterm birth and adverse perinatal outcomes in singleton gestations with a short cervix: a meta-analysis of individual patient data

BACKGROUND

The efficacy of vaginal progesterone for preventing preterm birth and adverse perinatal outcomes in singleton gestations with a short cervix has been questioned after publication of the OPPTIMUM study.

OBJECTIVE

To determine whether vaginal progesterone prevents preterm birth and improves perinatal outcomes in asymptomatic women with a singleton gestation and a midtrimester sonographic short cervix.

STUDY DESIGN

We searched MEDLINE, EMBASE, LILACS, and CINAHL (from their inception to September 2017); Cochrane databases; bibliographies; and conference proceedings for randomized controlled trials comparing vaginal progesterone vs placebo/no treatment in women with a singleton gestation and a midtrimester sonographic cervical length ≤25 mm. This was a systematic review and meta-analysis of individual patient data. The primary outcome was preterm birth <33 weeks of gestation. Secondary outcomes included adverse perinatal outcomes and neurodevelopmental and health outcomes at 2 years of age. Individual patient data were analyzed using a 2-stage approach. Pooled relative risks with 95% confidence intervals were calculated. Quality of evidence was assessed using the GRADE methodology.

RESULTS

Data were available from 974 women (498 allocated to vaginal progesterone, 476 allocated to placebo) with a cervical length ≤25 mm participating in 5 high-quality trials. Vaginal progesterone was associated with a significant reduction in the risk of preterm birth <33 weeks of gestation (relative risk, 0.62; 95% confidence interval, 0.47-0.81; P = .0006; high-quality evidence). Moreover, vaginal progesterone significantly decreased the risk of preterm birth <36, <35, <34, <32, <30, and <28 weeks of gestation; spontaneous preterm birth <33 and <34 weeks of gestation; respiratory distress syndrome; composite neonatal morbidity and mortality; birthweight <1500 and <2500 g; and admission to the neonatal intensive care unit (relative risks from 0.47-0.82; high-quality evidence for all). There were 7 (1.4%) neonatal deaths in the vaginal progesterone group and 15 (3.2%) in the placebo group (relative risk, 0.44; 95% confidence interval, 0.18-1.07; P = .07; low-quality evidence). Maternal adverse events, congenital anomalies, and adverse neurodevelopmental and health outcomes at 2 years of age did not differ between groups.

CONCLUSION

Vaginal progesterone decreases the risk of preterm birth and improves perinatal outcomes in singleton gestations with a midtrimester sonographic short cervix, without any demonstrable deleterious effects on childhood neurodevelopment.

Progesterone suppresses the lipopolysaccharide-induced pro-inflammatory response in primary mononuclear cells isolated from human placental blood

Progesterone is an essential hormone that induces deep immune adaptations favoring pregnancy maintenance. We aimed at evaluating the effects of progesterone on the synthesis of pro- and anti-inflammatory cytokines by mononuclear cells isolated from human placental blood stimulated with lipopolysaccharide, emulating an infection-inflammation environment. Mononuclear cells isolated form human placental blood were obtained from nine women undergoing elective cesarean delivery at term (not in labor), isolated by density gradient sedimentation, cultured and co-stimulated with lipopolysaccharide (500 ng/ml) from Escherichia coli in the presence or not of progesterone (0.01, 0.1, or 1.0 µM) for 24 h. Culture supernatants were assayed for pro-inflammatory (IL-1β, TNFα, IL-6), anti-inflammatory (IL-10) cytokines, chemokines (IL-8, MIP-1α) and total MMP-9 by ELISA. In comparison with basal conditions, lipopolysaccharide treatment induced IL-1β, TNFα, IL-6, IL-8, MIP-1α, and MMP-9 synthesis. lipopolysaccharide co-treatment with progesterone significantly decreased the bacterial endotoxin-induced IL-1β, TNF-α, IL-6, IL-8, and MIP-1α secretion. In contrast, co-treatment with progesterone increased the level of IL-10 secreted to the culture medium. The present results support the concept that progesterone can modulate--partially--the inflammatory response of professional immune cells isolated from placental blood. Therefore, progesterone might be part of the natural compensatory mechanism that limits the cytotoxic effects associated with an intrauterine infection process during gestation.

The rapid immunosuppression in phytohemagglutinin-activated human T cells is inhibited by the proliferative Ca(2+) influx induced by progesterone and analogs

Progesterone, an endogenous immunomodulator, suppresses human T-cell activation during pregnancy. A sustained Ca(2 +) influx is an important signal for T-cell proliferation after crosslinking of T-cell receptor/CD3 complexes by anti-CD3 antibodies or phytohemagglutinin (PHA). Progesterone targets cell membrane sites inducing rapid responses including elevated intracellular free calcium concentration ([Ca(2+)]i) and suppressed T-cell PHA-activated proliferation. Interestingly, both PHA and progesterone induce [Ca(2+)]i elevation, but it remains unclear whether the PHA-induced Ca(2+) influx is affected by progesterone leading to T-cell immunosuppression. Primary T-cells were isolated from human peripheral blood and the quench effect on intracellular fura-2 fluorescence of Mn(2+) was used to explore the responses to Ca(2+) influx with cell proliferation being determined by MTT assay. PHA-stimulated Ca(2+) influx was dose-dependently suppressed by progesterone and its agonist R5020, which correlated with PHA-activated T-cell proliferation inhibition. A similar dose-dependent suppression effect on cellular Ca(2+) influx and proliferation occurred with the TRPC channel inhibitor BTP2 and selective TRPC3 channel inhibitor Pyr3. In addition, two progesterone analogs, Org OD 02-0 and 20α-hydroxyprogesterone (20α-OHP), also produced dose-dependent suppression of Ca(2+) influx, but had no effect on proliferation. Finally, inhibition of PHA-activated T-cell proliferation by progesterone is further suppressed by 20α-OHP, but not by Org OD 02-0. Overall, progesterone and R5020 are able to rapidly decrease PHA-stimulated sustained Ca(2+) influx, probably via blockade of TRPC3 channels, which suppresses T-cell proliferation. Taken together, the roles of progesterone and its analogs regarding the rapid response Ca(2+) influx need to be further explored in relation to cytokine secretion and proliferation in activated T-cells.

Paraoxonases-1, -2 and -3: What are their functions?

Paraoxonase-1 (PON1), an esterase/lactonase primarily associated with plasma high-density lipoprotein (HDL), was the first member of this family of enzymes to be characterized. Its name was derived from its ability to hydrolyze paraoxon, the toxic metabolite of the insecticide parathion. Related enzymes PON2 and PON3 were named from their evolutionary relationship with PON1. Mice with each PON gene knocked out were generated at UCLA and have been key for elucidating their roles in organophosphorus (OP) metabolism, cardiovascular disease, innate immunity, obesity, and cancer. PON1 status, determined with two-substrate analyses, reveals an individual's functional Q192R genotype and activity levels. The three-dimensional structure for a chimeric PON1 has been useful for understanding the structural properties of PON1 and for engineering PON1 as a catalytic scavenger of OP compounds. All three PONs hydrolyze microbial N-acyl homoserine lactone quorum sensing factors, quenching Pseudomonas aeruginosa's pathogenesis. All three PONs modulate oxidative stress and inflammation. PON2 is localized in the mitochondria and endoplasmic reticulum. PON2 has potent antioxidant properties and is found at 3- to 4-fold higher levels in females than males, providing increased protection against oxidative stress, as observed in primary cultures of neurons and astrocytes from female mice compared with male mice. The higher levels of PON2 in females may explain the lower frequency of neurological and cardiovascular diseases in females and the ability to identify males but not females with Parkinson's disease using a special PON1 status assay. Less is known about PON3; however, recent experiments with PON3 knockout mice show them to be susceptible to obesity, gallstone formation and atherosclerosis. Like PONs 1 and 2, PON3 also appears to modulate oxidative stress. It is localized in the endoplasmic reticulum, mitochondria and on HDL. Both PON2 and PON3 are upregulated in cancer, favoring tumor progression through mitochondrial protection against oxidative stress and apoptosis.

Reduced levels of maternal progesterone during pregnancy increase the risk for allergic airway diseases in females only

Observational as well as experimental studies support that prenatal challenges seemed to be associated with an increased risk for allergic airway diseases in the offspring. However, insights into biomarkers involved in mediating this risk are largely elusive. We here aimed to test the association between endogenous and exogenous factors documented in pregnant women, including psychosocial, endocrine, and life style parameters, and the risk for allergic airway diseases in the children later in life. We further pursued to functionally test identified factors in a mouse model of an allergic airway response. In a prospectively designed pregnancy cohort (n = 409 families), women were recruited between the 4th and 12th week of pregnancy. To investigate an association between exposures during pregnancy and the incidence of allergic airway disease in children between 3 and 5 years of age, multiple logistic regression analyses were applied. Further, in prenatally stressed adult offspring of BALB/c-mated BALB/c female mice, asthma was experimentally induced by ovalbumin (OVA) sensitization. In addition to the prenatal stress challenge, some pregnant females were treated with the progesterone derivative dihydrodydrogesterone (DHD). In humans, we observed that high levels of maternal progesterone in early human pregnancies were associated with a decreased risk for an allergic airway disease (asthma or allergic rhinitis) in daughters (adjusted OR 0.92; 95% confidence interval [CI] 0.84 to 1.00) but not sons (aOR 1.02, 95% CI 0.94-1.10). In mice, prenatal DHD supplementation of stress-challenged dams attenuated prenatal stress-induced airway hyperresponsiveness exclusively in female offspring. Reduced levels of maternal progesterone during pregnancy-which can result from high stress perception-increase the risk for allergic airway diseases in females but not in males. Key messages: Lower maternal progesterone during pregnancy increases the risk for allergic airway disease only in female offspring. Prenatal progesterone supplementation ameliorates airway hyperreactivity in prenatally stressed murine offspring.

Progesterone to prevent spontaneous preterm birth

Preterm birth is the leading cause of perinatal morbidity and mortality worldwide, and its prevention is an important healthcare priority. Preterm parturition is one of the 'great obstetrical syndromes' and is caused by multiple etiologies. One of the mechanisms of disease is the untimely decline in progesterone action, which can present as a clinically silent sonographic short cervix in the midtrimester. The detection of a short cervix in the midtrimester is a powerful risk factor for preterm delivery. Vaginal progesterone can reduce the rate of preterm delivery by 45% and the rate of neonatal morbidity (admission to the neonatal intensive care unit, respiratory distress syndrome, need for mechanical ventilation, etc.). To prevent one case of spontaneous preterm birth <33 weeks of gestation, 11 patients with a short cervix would need to be treated (based on an individual patient meta-analysis). Vaginal progesterone reduces the rate of spontaneous preterm birth in women with a short cervix, both with and without a prior history of preterm birth. In patients with a prior history of preterm birth, vaginal progesterone is as effective as cervical cerclage to prevent preterm delivery. 17α-Hydroxyprogesterone caproate has not been shown to be effective in reducing the rate of spontaneous preterm birth in women with a short cervix.

Steroid profiling in pregnancy: a focus on the human fetus

In this review we focused on steroid metabolomics in human fetuses and newborns and its role in the physiology and pathophysiology of human pregnancy and subsequent stages of human life, and on the physiological relevance of steroids influencing the nervous systems with regards to their concentrations in the fetus. Steroid profiling provides valuable data for the diagnostics of diseases related to altered steroidogenesis in the fetal and maternal compartments and placenta. We outlined a potential use of steroid metabolomics for the prediction of reproductive disorders, misbalance of hypothalamic-pituitary-adrenal axis, and impaired insulin sensitivity in subsequent stages of human life. A possible role of steroids exhibiting a non-genomic effect in the development of gestational diabetes and in the neuroprotection via negative modulation of AMPA/kainate receptors was also indicated. Increasing progesterone synthesis and catabolism, declining production of tocolytic 5β-pregnane steroids, and rising activities of steroid sulfotransferases with the approaching term may be of importance in sustaining pregnancy. An increasing trend was demonstrated with advancing gestation toward the production of ketones (and 3β-hydroxyl groups in the case of 3α-hydroxy-steroids) was demonstrated in the fetus on the expense of 3α-hydroxy-, 17β-hydroxy-, and 20α-hydroxy-groups weakening in the sequence C17, C3, and C20. There was higher production of active progestogen but lower production of active estrogen and GABAergic steroids with the approaching term. Rising activities of placental CYP19A1 and oxidative isoforms of HSD17B, and of fetal CYP3A7 with advancing gestation may protect the fetus from hyperestrogenization. This article is part of a Special Issue entitled 'Pregnancy and Steroids'.

Progesterone regulates the expression and activity of two mouse isoforms of the glycoprotein folding sensor UDP-Glc: glycoprotein glucosyltransferase (UGGT)

UDP-Glucose:glycoprotein glucosyltransferase (UGGT) is a central component of the endoplasmic reticulum (ER) glycoprotein-folding quality control system, which prevents the exit of partially folded species. UGGT activity can be regulated by the accumulation of misfolded proteins in the ER, a stimulus that triggers a complex signaling pathway known as unfolded protein response (UPR) which is closely associated with inflammation and disease. In this work, we investigated the effect of progesterone (P4) on the expression and activity of UGGT in a mouse hybridoma. We detected the expression of two UGGT isoforms, UGGT1 and UGGT2, and demonstrated that both isoforms are active in these cells. Interestingly, the expression of each isoform is regulated by high physiological P4 concentrations. This work provides the first evidence of a hormonal regulation of UGGT isoform expression and activity, which might influence the glycoprotein quality control mechanism. These findings could contribute to the study of pathologies triggered by the accumulation of misfolded proteins.

Progesterone elicits an inhibitory effect upon LPS-induced innate immune response in pre-labor human amniotic epithelium

PROBLEM

Infection of human fetal membranes elicits secretion of pro-inflammatory modulators through its innate immune capacities. We investigated the effect of lipopolysacharide (LPS) and progesterone (P4) upon expression of TLR-4/MyD88, TNFα, IL-6, IL-8, IL-10, and HBD2 on the human amniotic epithelium.

METHOD OF STUDY

Explants of the human amniotic epithelium were pre-treated with 0.01, 0.1, and 1.0 μM of P4; then cotreated with 1000 ng/mL LPS. TLR-4 was immuno-detected, and concentrations of MyD88, TNFα, IL-6, IL-8, IL-10, and HBD2 were quantified by ELISA.

RESULTS

P4 significantly reduced the expression of LPS-induced TLR-4/MyD88. LPS increased the concentrations of TNFα, IL-6, IL-8, IL-10, and HBD2 by factors of 30-, eight, three, three, and fivefold, respectively. P4 at 1.0 μM was the most effective dose to blunt the secretion of TNFα, IL-6, and HBD-2. RU-486 blocks the effect of P4.

CONCLUSION

P4 inhibited LPS-induced TLR-4/MyD88 and pro-inflammatory factors in the human amniotic epithelium. These results could explain partially how P4 can protect the amniotic region of fetal membranes and generate a compensatory mechanism that limits the secretion of pro-inflammatory modulators, which could jeopardize the immune privilege during pregnancy.

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) enhances placental inflammation

Preterm birth is a leading cause of perinatal morbidity and mortality that is often associated with ascending infections from the lower genital tract. Recent studies with animal models have suggested that developmental exposure to the environmental toxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can increase the risk of preterm birth in the offspring. How TCDD may modify placental immunity to ascending infections is unclear. Therefore, we studied the effects of TCDD treatment on basal and Escherichia coli-stimulated cytokine production by placental explants. Cultures of second-trimester placentas were treated with up to 40 nM TCDD for 72 h and then stimulated with 10(7)CFU/ml E. coli for an additional 24h. Concentrations of cytokines and PGE2 were measured in conditioned medium by immunoassay. TCDD exposure increased mRNA levels of IL-1β by unstimulated cultures, but no effects on protein levels of this cytokine were detected. TNF-α production was unaffected by TCDD for unstimulated cultures, but pre-treatment with 40 nM TCDD significantly increased E. coli-stimulated TNF-α production. Both basal and bacteria-stimulated PGE2 and COX-2 gene expression were enhanced by TCDD pretreatment. In contrast, production of the anti-inflammatory cytokine, IL-10, was reduced by TCDD pretreatment for both unstimulated and E. coli-stimulated cultures. No effect of TCDD on the viability of the cultures was detected. These results suggest that TCDD exposure may shift immunity to enhance a proinflammatory phenotype at the maternal-fetal interface that could increase the risk of infection-mediated preterm birth.

Change in mononuclear leukocyte responsiveness in midpregnancy and subsequent preterm birth

OBJECTIVE

To estimate the associations of change in immune response with preterm delivery, omega-3 supplementation, and fish diet.

METHODS

This was an ancillary study to a randomized trial of omega-3 fatty acid supplementation for the prevention of recurrent preterm birth. In vitro maternal peripheral blood mononuclear leukocyte production of the anti-inflammatory cytokine, interleukin-10, and the proinflammatory cytokine, tumor necrosis factor-α, in response to stimulation with lipopolysaccharide, was measured at 16-22 weeks of gestation (baseline) and again at 25-28 weeks of gestation (follow-up) among women with prior spontaneous preterm birth. Changes in concentrations from baseline to follow-up ([INCREMENT]) were compared separately among groups defined by gestational age category at delivery, fish diet history, and omega-3 compared with placebo treatment assignment with Kruskal-Wallis tests.

RESULTS

Interleukin-10 [INCREMENT] differed by gestational age category among 292 women with paired assays. Concentrations increased less in women delivering between 35 and 36 6/7 weeks of gestation (48.9 pg/mL) compared with women delivering at term (159.3 pg/mL) and decreased by 65.2 pg/mL in women delivering before 35 weeks of gestation (P=.01). Tumor necrosis factor-α Δ also differed by gestational age category among 319 women, but the pattern was inconsistent. Those delivering between 35 and 36 6/7 weeks of gestation exhibited decreased concentrations of tumor necrosis factor-α at follow-up compared with baseline (-356.0 pg/mL); concentrations increased among women delivering before 35 weeks of gestation and those delivering at term, 132.1 and 86.9 pg/mL (P=.03). Interleukin-10 Δ and tumor necrosis factor-α Δ were unaffected by either omega-3 supplementation or fish diet.

CONCLUSION

Recurrent preterm birth was associated with decreased peripheral blood mononuclear leukocyte production of interleukin-10 in response to a stimulus during the second trimester.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT00135902.

LEVEL OF EVIDENCE

II.

Sex-specific effect of first-trimester maternal progesterone on birthweight

STUDY QUESTION

Are maternal progesterone levels in early pregnancy associated with fetal birthweight?

SUMMARY ANSWER

Low levels of first-trimester maternal progesterone are significantly associated with a reduction in birthweight in girls, but not boys.

WHAT IS ALREADY KNOWN

Progesterone in the third trimester of pregnancy has previously been related to birthweight in humans.

STUDY DESIGN, SIZE, DURATION

Pregnant women between gestational weeks 4 and 12 were recruited by 99 obstetricians in private practice and enrolled in a prospective cohort study. A follow-up took place at birth. Women younger than 18 years, who had undergone fertility treatments or were diagnosed with infectious diseases, were excluded from the study. A subgroup of 906 participants in whom progesterone had been measured was then selected retrospectively based on the following criteria: no miscarriages, elective abortions or pregnancy complications, infections or multiple births. Data from the follow-up were available for 623 women, who were included in the analyses.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study was coordinated at the Charité University Medicine in Berlin, Germany. Anthropometric, medical and psychosocial information were collected and serum progesterone and estradiol levels were measured in women during the first trimester of pregnancy, followed by the documentation of the pregnancy outcome at birth. Univariable and multivariable regression analyses were performed to identify maternal markers, among them progesterone, affecting birthweight and to determine environmental and maternal factors that are associated with maternal progesterone levels during pregnancy.

MAIN RESULTS AND THE ROLE OF CHANCE

In the multivariable regression model, each increase in maternal progesterone by 1 ng/ml during the first trimester increased girls' birthweight by 10.17 g (95% CI: 2.03-18.31 g). If the mother carried a boy, maternal smoking and perceived worries during early pregnancy predicted a reduced birthweight, irrespective of progesterone levels. Maternal body mass index over 25 and maternal age <21 years significantly correlated with the reduced levels of progesterone. Correlations between environmental challenges and maternal progesterone did not reach levels of significance. Since the analyses were exploratory, the likelihood that results may be due to chance is increased.

LIMITATIONS, REASONS FOR CAUTION

Due to the exploratory nature of the analyses, results need to be independently confirmed in a larger sample. Furthermore, our findings pertain to pregnant women without pregnancy complications or fertility treatments.

WIDER IMPLICATIONS OF THE FINDINGS

Maternal progesterone during early pregnancy is an indicator of subsequent fetal development in female children. Future studies should confirm this relationship and determine whether maternal progesterone is a useful tool in predicting pregnancies at risk resulting in the birth of a girl with low birthweight. Detailed identification of environmental factors modulating maternal progesterone levels should be addressed in future studies.

STUDY FUNDING/POTENTIAL COMPETING INTERESTS

Financial support was provided by the Alexander von Humboldt Foundation, Excellence Initiative of the Hamburg Foundation for Research and the Association for Prevention and Information for Allergy and Asthma (Pina e.V.). The authors have no conflict of interest.

The role of 17 alpha-hydroxyprogesterone caproate in the prevention of preterm birth

Preterm birth is a major public-health problem in the USA, which has higher rates of preterm birth than most other developed countries. Attempts at the prevention of preterm birth have been largely unsuccessful. The recent publication of a large, multicenter, randomized trial of 17 alpha-hydroxyprogesterone caproate, which showed efficacy in preventing recurrent preterm delivery, has sparked renewed interest in progestational drugs in general and this compound in particular for use in preventing preterm delivery. Although this drug is not currently commercially available, an application has been made to the US FDA to produce 17 alpha-hydroxyprogesterone caproate, as Gestiva() for the prevention of preterm delivery.

Inhibition of diacylglycerol-sensitive TRPC channels by synthetic and natural steroids

TRPC channels are a family of nonselective cation channels that regulate ion homeostasis and intracellular Ca²⁺ signaling in numerous cell types. Important physiological functions such as vasoregulation, neuronal growth, and pheromone recognition have been assigned to this class of ion channels. Despite their physiological relevance, few selective pharmacological tools are available to study TRPC channel function. We, therefore, screened a selection of pharmacologically active compounds for TRPC modulating activity. We found that the synthetic gestagen norgestimate inhibited diacylglycerol-sensitive TRPC3 and TRPC6 with IC₅₀s of 3–5 µM, while half-maximal inhibition of TRPC5 required significantly higher compound concentrations (>10 µM). Norgestimate blocked TRPC-mediated vasopressin-induced cation currents in A7r5 smooth muscle cells and caused vasorelaxation of isolated rat aorta, indicating that norgestimate could be an interesting tool for the investigation of TRP channel function in native cells and tissues. The steroid hormone progesterone, which is structurally related to norgestimate, also inhibited TRPC channel activity with IC₅₀s ranging from 6 to 18 µM but showed little subtype selectivity. Thus, TRPC channel inhibition by high gestational levels of progesterone may contribute to the physiological decrease of uterine contractility and immunosuppression during pregnancy.

Vessel remodelling, pregnancy hormones and extravillous trophoblast function

During early human pregnancy, extravillous trophoblast (EVT) cells from the placenta invade the uterine decidual spiral arterioles and mediate the remodelling of these vessels such that a low pressure, high blood flow can be supplied to the placenta. This is essential to facilitate normal growth and development of the foetus. Defects in remodelling can manifest as the serious pregnancy complication pre-eclampsia. During the period of vessel remodelling three key pregnancy-associated hormones, human chorionic gonadotrophin (hCG), progesterone (P(4)) and oestradiol (E(2)), are found in high concentrations at the maternal-foetal interface. Potentially these hormones may control EVT movement and thus act as regulators of vessel remodelling. This review will discuss what is known about how these hormones affect EVT proliferation, migration and invasion during vascular remodelling and the potential relationship between hCG, P(4), E(2) and the development of pre-eclampsia.

Immunopharmacology of ulipristal as an emergency contraceptive

A new progesterone antagonist, ulipristal has been made available as an emergency contraceptive. Ulipristal’s major mechanism of action as an emergency contraceptive has been ascribed to its ability to delay ovulation beyond the life span of the sperm. This paper analyzes the potential action of ulipristal (1) when unprotected intercourse and administration of ulipristal occur outside the fertility window and (2) when unprotected intercourse and administration of ulipristal occur at or within 24 hours of ovulation. When unprotected intercourse and the use of a single low dose of ulipristal occur outside of the fertility window, ulipristal behaves like a placebo. When unprotected intercourse and the use of a single low dose of ulipristal occur within the fertility window but before ovulation, ulipristal behaves like an emergency contraceptive by delaying ovulation and thereby preventing fertilization. When unprotected intercourse and the administration of ulipristal occur at or within 24 hours of ovulation, then ulipristal has an abortifacient action. It is proposed that the abortifacient mechanism of a low dose of ulipristal taken after fertilization but before implantation is due to the ability of ulipristal to block the maternal innate immune system to become immunotolerant to the paternal allogenic embryo. Progesterone’s critical immunotolerant actions involving early pregnancy factor, progesterone-induced blocking factor, and uterine natural killer cells are compromised by ulipristal.

Contribution of different placental cells to the expression and stimulation of antimicrobial proteins (AMPs)

The placenta is a major barrier that prevents potentially infectious agents from causing fetal diseases or related complications during pregnancy. Therefore, we postulated that the placenta might express a broad repertoire of antimicrobial proteins as well as inflammatory chemokines and cytokines to combat invading microorganisms. Here we demonstrate that placental cells indeed express a wide range of AMPs (antimicrobial peptides and proteins) including bactericidal/permeability-increasing protein (BPI), secretory leukocyte protease inhibitor (SLPI), human β-defensin 2 (hBD2), acyloxyacyl hydrolase (AOAH), and cathelicidin (CAP18). In addition, these cells also secrete pro-inflammatory cytokines and chemokines upon stimulation with bacterial ligands. Notably, we show that BPI expression by placental cells could be completely attributed to granulocytes while highly purified placental trophoblasts expressed only a subset of the AMPs like SLPI. Unexpectedly, trophoblast AMPs did not exhibit inducible secretion in response to various TLR ligands and further investigations showed that the unresponsiveness of trophoblasts to lipopolysaccharide (LPS) was due to a lack of TLR4 expression. In summary, we have shown that the expression of different AMPs can be allocated to various cells in the placenta and the repertoire of the AMPs expressed by placental cells is a result of a cooperation of leukocytes as well as cells from embryonic origin.

The effects of human chorionic gonadotrophin, progesterone and oestradiol on trophoblast function

Remodelling of the uterine vasculature during the first trimester of human pregnancy requires invasion of trophoblast from the placenta into decidual spiral arterioles. The pregnancy-associated hormones human chorionic gonadotropin (hCG), progesterone (P(4)) and oestradiol (E(2)) are present at high concentrations at the maternal-fetal interface during the remodelling period and thus may contribute to the regulation of trophoblast movement. This study examined the effects of these hormones on trophoblast functions. HTR8/SVneo cells were treated with hCG (5-100mIU/mL), P(4) (20nM-20μM) or E(2) (0.07-734nM). hCG significantly stimulated migration and MMP-9 activity but did not affect cell numbers. P(4) significantly inhibited migration, MMP-2 and -9 activity and reduced cell numbers. E(2) had no effect on migration, MMP activity or cell numbers. We conclude that hCG and P(4), but not E(2), play direct roles in controlling trophoblast invasion, acting as positive and negative stimuli respectively to regulate trophoblast movement during vascular remodelling in early pregnancy.

Progesterone effects on preterm birth in high-risk pregnancies: a randomized placebo-controlled trial

PURPOSE

The purpose of this study was to evaluate whether the prophylactic administration of vaginal progesterone would reduce the preterm birth rate in high-risk population including singleton and twin pregnancies.

METHODS

This was a randomized, double blind, placebo-controlled study that included 150 high-risk pregnancies. Risk groups included prior spontaneous preterm birth, twin pregnancy, and uterine malformation. Micronized progesterone or placebo (100 mg) was administered daily by vaginal suppository between 24 and 34 weeks of gestation. We compared progesterone and placebo groups for incidence of preterm labor and preterm delivery. Data were compared by χ² analysis and Fisher exact test.

RESULTS

There was a statistically significant difference in the rate of preterm labor between placebo and progesterone groups (45.7 vs. 25%, respectively; p < 0.05). More women delivered before 37 weeks in placebo group (57.2%) than in progesterone group (40%; p < 0.05). Administering progesterone also reduced the preterm birth before 34 weeks of gestation. The difference between placebo and progesterone group was statistically significant (24.3 vs. 8.8%; p < 0.05). However, there was no significant difference in neonatal death between placebo and progesterone groups.

CONCLUSION

Prophylactic vaginal progesterone reduced the rate of preterm labor and preterm delivery in high-risk pregnancies.

Influence of hormone supplementation therapy on the incidence of denture stomatitis and on chemiluminescent activity of polymorphonuclear granulocytes in blood of menopausal-aged women

Background

Menopause is a health and social problem that affects a large number of women. Inadequate quantity of steroid hormones also impacts quality of the mucous membrane of the oral cavity. During menopausal age, many women wear removable prosthetic restorations in order to replace missing teeth. Such restorations may facilitate the development of inflammations in the surface of the oral cavity, referred to as denture stomatitis.

Objective

The aim of the study was to evaluate the influence of hormone supplementation therapy on the incidence of Candida-associated denture stomatitis and on the metabolic activity of polymorphonuclear granulocytes in peripheral blood of female patients.

Materials and methods

The study was conducted on a group of women in menopausal age, users of hormone replacement therapy and of removable prosthetic restorations. Female patients were subjected to a clinical study that included interviews and physical examinations. Laboratory microbiological examinations were completed on the basis of direct swabs collected from the mucous membrane of the oral cavity and from the surface of dentures. Metabolic activity of polymorphonuclear granulocytes in peripheral blood of female patients was evaluated by means of a chemiluminescence test.

Results

Candida-associated denture stomatitis observed was characterized by a strong growth of fungi and a lower chemiluminescent activity of neutrophils in blood of female patients undergoing hormone supplementation therapy.

Conclusions

Patients using hormone supplementation therapy and removable prosthetic restorations constitute a high-risk group for Candida infections and inflammations of the mucous membrane of the oral cavity; thus they should remain under constant dental control.

Progesterone regulation of uterine dendritic cell function in rodents is dependent on the stage of estrous cycle

Steroid hormones, such as progesterone, are able to modify immunity and influence disease outcome. Dendritic cells (DCs) drive potent immune responses, express receptors for steroid hormones, and may be a primary target of steroid hormone actions during infection of the genital tract, including uterine tissue. Here, we report that progesterone limited DC-associated activation marker expression and inhibited cytokine secretion by uterine DCs, which was associated with changes in signal transducer and activator of transcription 1 (STAT1) activity. We also found that DCs from mice at stages with higher progesterone concentrations (diestrus, metaestrus) were more sensitive to progesterone than those in stages with lower progesterone concentrations (proestrus, estrus), both in vitro and in vivo. This difference correlated with the levels of progesterone receptor expressed by DCs. These data suggest that progesterone regulates DC function and could contribute to the susceptibility of females to uterine and other genital tract infections at selected time periods throughout the life cycle.

Prostaglandin treatment is associated with a withdrawal of progesterone and androgen at the receptor level in the uterine cervix

Treatment with prostaglandin(PG)-E2 is clinically efficient for cervical priming. The aim of this study was to evaluate the impact of PG-E2 on the expression of the progesterone (PR), androgen (AR) and glucocorticoid (GR) receptors in human uterine cervix in prolonged pregnancy. The study groups were postterm nulliparous women with unripe cervices undergoing cervical priming with PG-E2 before labor induction. Responders (n = 12) who delivered vaginally were compared with non-responders (n = 10), who underwent cesarean section due to failure to progress to the active phase of labor. Controls (n = 18) with vaginal partus at a normal gestational age served as a reference group. Cervical levels of PR-A and PR- B isoforms, AR and GR, serum levels of their ligands and sex hormone-binding globulin (SHBG) were quantified. The responder group displayed lower total PR-AB and AR protein levels as compared to non-responders, and lower PR-B and AR protein levels as compared to controls. In addition, the PR mRNA level was lower in responders as compared to non-responders. The GR protein level did not differ between the groups. We conclude that successful PG-E2 priming was followed by a progesterone and androgen withdrawal at the receptor level in the uterine cervix.

Impact of female sex hormones on the maturation and function of human dendritic cells

PROBLEM

During pregnancy, the immune and the endocrine system cooperate to ensure that the fetal allograft develops without eliciting a maternal immune response. This is presumably in part achieved by dendritic cells (DCs) that play a dominant role in maintaining peripheral tolerance. In this study, we investigated whether female sex hormones, such as human chorionic gonadotropin (hCG), progesterone (Prog), and estradiol (E2), which are highly elevated during pregnancy, induce the differentiation of DCs into a tolerance-inducing phenotype.

METHODS/RESULTS

Immature DCs were generated from blood-derived monocytes and differentiated in the presence of hCG, Prog, E2, or Dexamethasone (Dex) as a control. Unlike Dex, female sex hormones did not prevent the upregulation of surface markers characteristic for mature DCs, such as CD40, CD83, and CD86, except for hCG, which inhibited HLA-DR expression. Similarly, hCG, Prog, and E2 had any impact on neither the rearrangement of the F-actin cytoskeleton nor the enhanced chemokine secretion following DC maturation, both of which were strongly altered by Dex. Nevertheless, the T-cell stimulatory capacity of DCs was significantly reduced after hCG and E2 exposure.

CONCLUSION

Our findings suggest that the female sex hormones hCG and E2 inhibit the T-cell stimulatory capacity of DCs, which may help in preventing an allogenic T-cell response against the embryo.

Systemic reduction of functionally suppressive CD4dimCD25highFoxp3+ Tregs in human second trimester pregnancy is induced by progesterone and 17beta-estradiol

CD4(+)CD25(high) regulatory T cells (Tregs) are implicated in the maintenance of murine pregnancy. However, reports regarding circulating Treg frequencies in human pregnancy are inconsistent, and the functionality and phenotype of these cells in pregnancy have not been clarified. The aim of this study was to determine the frequency, phenotype, and function of circulating Tregs in the second trimester of human pregnancy and the influence of progesterone and 17beta-estradiol on Treg phenotype and frequency. Based on expressions of Foxp3, CD127, and HLA-DR as determined by multicolor flow cytometry, we defined a proper CD4(dim)CD25(high) Treg population and showed, in contrast to most previous reports, that this population was reduced in second trimester of pregnancy. Unexpectedly, Foxp3 expression was decreased in the Treg, as well as in the CD4(+) population. These changes could be replicated in an in vitro system resembling the pregnancy hormonal milieu, where 17beta-estradiol, and in particular progesterone, induced, in line with the pregnancy situation, a reduction of CD4(dim)CD25(high)Foxp3(+) cells in PBMC from nonpregnant women. By coculturing FACS-sorted Tregs and autologous CD4(+)CD25(-) responder cells, we showed that Tregs from pregnant women still displayed the same suppressive capacity as nonpregnant women in terms of suppressing IL-2, TNF-alpha, and IFN-gamma secretion from responder cells while efficiently producing IL-4 and IL-10. Our findings support the view of hormones, particularly progesterone, as critical regulators of Tregs in pregnancy. Furthermore, we suggest that in the light of the results of this study, early data on circulating Treg frequencies in pregnancy need reevaluation.

Mifepristone acts as progesterone antagonist of non-genomic responses but inhibits phytohemagglutinin-induced proliferation in human T cells

BACKGROUND

Progesterone is an endogenous immunomodulator that suppresses T cell activation during pregnancy. The stimulation of membrane progesterone receptors (mPRs) would seem to be the cause of rapid non-genomic responses in human peripheral T cells, such as an elevation of intracellular calcium ([Ca(2+)](i)) and decreased intracellular pH (pH(i)). Mifepristone (RU486) produces mixed agonist/antagonist effects on immune cells compared with progesterone. We explored whether RU486 is an antagonist to mPRs and can block rapid non-genomic responses and the induction by phytohemagglutinin (PHA) of cell proliferation.

METHODS

Human male peripheral T cell responses in terms of pH(i) and [Ca(2+)](i) changes were measured using the fluorescent dyes, 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) and fura-2, respectively. Expression of mPR mRNA was determined by RT-PCR analysis. Cell proliferation and cell toxicity were determined by [(3)H]-thymidine incorporation and MTT assay, respectively.

RESULTS

The mRNAs of mPRalpha, mPRbeta and mPRgamma were expressed in T cells. RU486 blocked progesterone-mediated rapid responses including, the [Ca(2+)](i) increase and pH(i) decrease, in a dose related manner. RU486 did not block, but enhanced, the inhibitory effect of progesterone on PHA induced cell proliferation. RU486 alone inhibited proliferation induced by PHA and at >25 microM seems to be cytotoxic against resting T cells (P < 0.01).

CONCLUSIONS

RU486 is antagonistic to the rapid mPR-mediated non-genomic responses, but is synergistic with progesterone with respect to the inhibition of PHA-induced cell proliferation. Our findings shine new light on RU486's clinical application and how this relates to the non-genomic rapid physiological responses caused by progesterone.

Inhibitory effects of progesterone differ in dendritic cells from female and male rodents

BACKGROUND

Steroid hormones, such as progesterone, are known to have immunomodulatory effects. Our research group previously reported direct effects of progesterone on dendritic cells (DCs) from female rodents. Primarily affecting mature DC function, progesterone effects included inhibition of proinflammatory cytokine secretion, downregulation of cell surface marker (major histocompatibility complex class II, CD80) expression, and decreased T-cell proliferative capacity, and were likely mediated through progesterone receptor (PR) because the PR antagonist RU486 reversed these effects.

OBJECTIVE

The goal of this study was to assess differences in response to progesterone by DCs from female and male rodents.

METHODS

Using real-time reverse-transcriptase polymerase chain reaction, transcriptional expression of steroid hormone receptors was measured in immature bone marrow-derived DCs (BMDCs) from male and female rats. Expression of steroid hormone receptor protein was also assessed in these cells using flow cytometry and fluorescence microscopy. To evaluate functional differences between BMDCs from female and male rats in response to the steroid hormone progesterone, levels of secreted cytokines were measured using enzyme-linked immunosorbent assay.

RESULTS

Higher numbers of immature BMDCs from males expressed glucocorticoid receptor (GR) and androgen receptor (AR) proteins compared with females (males vs females, mean [SD]: GR = 68.75 [7.27] vs 43.61 [13.97], P = NS; AR = 75.99 [15.38] vs 8.25 [1.88], P = 0.002), whereas higher numbers of immature BMDCs from females expressed PR protein compared with males (females vs males: PR = 74.19 [12.11] vs 14.14 [4.55], P = 0.043). These differences were not found at the level of transcription (females vs males: GR = 0.088 vs 0.073, P = NS; AR = 0.076 vs 0.069, P = NS; PR = 0.075 vs 0.065, P = NS). Compared with those from females, mature BMDCs from males produced higher quantities of cytokines (tumor necrosis factor-alpha [TNF-alpha], interleukin [IL]-1beta, IL-10) (females vs males: TNF-alpha = 920.0 [79.25] vs 1100.61 [107.97], P = NS; IL-1beta = 146.60 [38.04] vs 191.10 [10.47], P = NS; IL-10 = 167.25 [4.50] vs 206.15 [23.48], P = NS). Conversely, BMDCs from females were more sensitive to progesterone, as indicated by a more dramatic reduction in proinflammatory cytokine secretion (females vs males, highest concentration of progesterone: TNF-alpha = 268.94 [28.59] vs 589.91 [100.98], P = 0.04; IL-1beta = 119.50 [10.32] vs 154.35 [6.22], P = NS).

CONCLUSIONS

These findings suggest that progesterone effects on DCs in rodents may be more pronounced in females than in males, and this is likely due to differences in PR protein expression. Our observations may help elucidate disparities in the incidence and severity of autoimmune disorders between females and males, and the role specific steroid hormones play in regulating immune responses.

Progesterone withdrawal promotes remodeling processes in the nonpregnant mouse cervix

Prepartum cervical ripening is associated with remodeling of collagen structure and with inflammation. Progesterone withdrawal is critical for parturition, but the effects of progesterone decline on cervical morphology are unknown. The present study tested the hypothesis that progesterone withdrawal promotes processes associated with remodeling of the cervix. Adult, virgin, female C57BL/6 mice received silastic capsules with oil vehicle or estradiol plus progesterone to parallel concentrations in circulation during pregnancy. After 17 days of estradiol and progesterone treatment, the progesterone implant was removed from one group. Mice in each group were killed 15, 18, or 19 days after placement of capsules. Sections of cervix were stained for collagen, and the densities of macrophages, neutrophils, and area with nerve fibers were assessed. Treatment with gonadal steroids promoted hypertrophy of the cervix, as well as reduced collagen and increased area with nerve fibers compared with vehicle-treated controls. Removal of the progesterone capsule did not affect hypertrophy or innervation, but it did reduce collagen. By contrast, significantly more macrophages and neutrophils were present in the cervix on Days 18 and 19 (i.e., by 24 and 48 h after withdrawal of the progesterone capsule); the immune cell census was equivalent to that in vehicle controls. Findings indicate that gonadal steroids, comparable to those during pregnancy, promote hypertrophy and suppress immigration of immune cells in the cervix. Therefore, in a nonpregnant murine model for parturition, progesterone withdrawal is suggested to recruit immune cells and processes that remodel the cervix.