Villous Trophoblast Differentiation Research Articles

USING A MULTI-OMICS LANDSCAPE OF THE MATERNAL-FETAL INTERFACE TO MODEL THE LONGITUDINAL PATHOGENESIS OF EARLY-ONSET PRE-ECLAMPSIA

Objective: Pre-eclampsia (PE) is a syndrome that affects multiple organ systems and is the most severe hypertensive disorder in pregnancy. It frequently leads to preterm delivery, maternal and fetal morbidity and mortality and life-long complications. We currently lack efficient screening tools and early therapies to address PE. Design and method: To identify candidate biomarkers and operative pathways in early onset PE (eoPE, severe PE with onset before week 34), we performed spatio-temporal multi-omics profiling of human eoPE placentae and healthy controls, and validated targets in early gestation in a longitudinal clinical cohort. We used a single-nuclei RNA-sequencing combined with spatial proteo- and transcriptomics and mechanistic in vitro signalling analyses to bridge the gap from late pregnancy disease to early pregnancy pathomechanisms. Results: We discovered a key disruption in villous trophoblast differentiation, which is driven by the increase of transcriptional coactivator p300, that ultimately ends with a senescence-associated secretory phenotype (SASP) of trophoblasts in eoPE. We found a significant increase in the senescence markers in preeclamptic maternal serum in early gestation and late gestation, before the development of clinical symptoms, indicating that the placental syndrome drives systemic maternal syndrome, even before clinical manifestation of eoPE. Conclusions: Our work describes a new disease progression model, starting with dysregulated transition in villous trophoblast differentiation. Our study identifies potential pathophysiology-relevant biomarkers for the early diagnosis of the disease as well as possible targets for interventions, which would be crucial steps toward protecting the mother and child from gestational mortality and morbidity and an increased risk of cardiovascular disease later in life.

Effect of high fat diet on maternal behavior, brain-derived neurotrophic factor and neural stem cell proliferation in mice expressing human placental lactogen during pregnancy.

Maternal obesity is a serious health concern because it increases risks of neurological disorders, including anxiety and peripartum depression. In mice, a high fat diet (HFD) in pregnancy can negatively affect placental structure and function as well as maternal behavior reflected by impaired nest building and pup-retrieval. In humans, maternal obesity in pregnancy is associated with reduced placental lactogen (PL) gene expression, which has been linked to a higher risk of depression. PL acting predominantly through the prolactin receptor maintains energy homeostasis and is a marker of placenta villous trophoblast differentiation during pregnancy. Impaired neurogenesis and low serum levels of brain-derived neurotrophic factor (BDNF) have also been implicated in depression. Augmented neurogenesis in brain during pregnancy was reported in the subventricular zone (SVZ) of mice at gestation day 7 and linked to increased prolactin receptor signaling. Here, we used transgenic CD-1 mice that express human (h) PL during pregnancy to investigate whether the negative effects of diet on maternal behavior are mitigated in these (CD-1[hGH/PL]) mice. Specifically, we examined the effect of a HFD on nest building prepartum and pup retrieval postpartum, as well as on brain BDNF levels and neurogenesis. In contrast to wild-type CD-1[WT]mice, CD-1[hGH/PL] mice displayed significantly less anxiety-like behavior, and showed no impairment in prepartum nest building or postpartum pup-retrieval when fed a HFD. Furthermore, the HFD decreased prepartum and increased postpartum BDNF levels in CD-1[WT] but not CD-1[hGH/PL] mice. Finally, neurogenesis in the SVZ as well as phosphorylated mitogen-activated protein kinase, indicative of lactogenic signaling, appeared unaffected by pregnancy and diet at gestation day 7 in CD-1[hGH/PL] mice. These observations indicate that CD-1[hGH/PL] mice are resistant to the negative effects of HFD reported for CD-1[WT] mice, including effects on maternal behaviors and BDNF levels, and potentially, neurogenesis. This difference probably reflects a direct or indirect effect of the products of the hGH/PL transgene.

Functional reorganization of monoamine transport systems during villous trophoblast differentiation: evidence of distinct differences between primary human trophoblasts and BeWo cells

BackgroundThree primary monoamines—serotonin, norepinephrine, and dopamine—play major roles in the placenta-fetal brain axis. Analogously to the brain, the placenta has transport mechanisms that actively take up these monoamines into trophoblast cells. These transporters are known to play important roles in the differentiated syncytiotrophoblast layer, but their status and activities in the undifferentiated, progenitor cytotrophoblast cells are not well understood. Thus, we have explored the cellular handling and regulation of monoamine transporters during the phenotypic transitioning of cytotrophoblasts along the villous pathway.MethodsExperiments were conducted with two cellular models of syncytium development: primary trophoblast cells isolated from the human term placenta (PHT), and the choriocarcinoma-derived BeWo cell line. The gene and protein expression of membrane transporters for serotonin (SERT), norepinephrine (NET), dopamine (DAT), and organic cation transporter 3 (OCT3) was determined by quantitative PCR and Western blot analysis, respectively. Subsequently, the effect of trophoblast differentiation on transporter activity was analyzed by monoamine uptake into cells.ResultsWe present multiple lines of evidence of changes in the transcriptional and functional regulation of monoamine transporters associated with trophoblast differentiation. These include enhancement of SERT and DAT gene and protein expression in BeWo cells. On the other hand, in PHT cells we report negative modulation of SERT, NET, and OCT3 protein expression. We show that OCT3 is the dominant monoamine transporter in PHT cells, and its main functional impact is on serotonin uptake, while passive transport strongly contributes to norepinephrine and dopamine uptake. Further, we show that a wide range of selective serotonin reuptake inhibitors affect serotonin cellular accumulation, at pharmacologically relevant drug concentrations, via their action on both OCT3 and SERT. Finally, we demonstrate that BeWo cells do not well reflect the molecular mechanisms and properties of healthy human trophoblast cells.ConclusionsCollectively, our findings provide insights into the regulation of monoamine transport during trophoblast differentiation and present important considerations regarding appropriate in vitro models for studying monoamine regulation in the placenta.

Deciphering villous and extravillous trophoblast differentiation: Participation of the Krüppel-like transcription factor 6

Deciphering villous and extravillous trophoblast differentiation: Participation of the Krüppel-like transcription factor 6

Does LIN28B gene dysregulation make women more likely to abort?

BackgroundLIN28B plays an important role in early embryonic development, but its role in villous trophoblast implantation and differentiation remains unknown. This study aims to verify the role of LIN28B in trophoblastic villous tissue and cells from women with URSA (unexplained recurrent spontaneous abortion) and artificial termination of pregnancy (negative control, NC).MethodsThe LIN28B gene and its protein expression level were detected with real-time quantitative PCR, Western immunoblotting analysis, and immunocytochemistry. The gene was also overexpressed in chorionic villous cell lines (HTR-8/SVneo and BeWo) to examine its effect on trophoblast function.ResultsThe expression of LIN28B mRNA and protein of URSA villi was lower than that in the NC group. At the cellular level, overexpression of LIN28B enhanced cellular migration, and invasion, and inhibited apoptosis. LIN28B may inhibit apoptosis by promoting Akt phosphorylation and by inhibiting Bad phosphorylation and Bcl-2 expression. In addition, LIN28B inhibited cell fusion and reduced cellular syncytia.ConclusionsLIN28B can inhibit cell invasion and migration in vitro and promote apoptosis and fusion. The low expression of LIN28B in URSA villous trophoblast cells may be one of the causes of abortion. The role of LIN28B in villous trophoblasts needs further study.Lay summaryPropagation of offspring is of great significance to the continuation of the human race. However, continuous pregnancy is more difficult for some women, especially women who have multiple miscarriages. One important contributor is the cessation of development caused by genetic factors of the embryo, but there are still many unknown reasons. We investigated the LIN28B gene which is a possible pathogenic factor in the placenta. We collected 25 cases of abortion in the experimental group (unexplained recurrent abortion group) and 25 in the control group (artificial termination of pregnancy group): on average at 7–8 weeks of pregnancy. We tested the function of lin28b in these samples and verified its function in cell lines. LIN28B plays an important role in maintaining early pregnancy by promoting the invasion of villous cells, inhibiting apoptosis and fusion, and the reduction of LIN28B expression may lead to the occurrence of early miscarriage.

Induction of the PPARγ (Peroxisome Proliferator-Activated Receptor γ)-GCM1 (Glial Cell Missing 1) Syncytialization Axis Reduces sFLT1 (Soluble fms-Like Tyrosine Kinase 1) in the Preeclamptic Placenta.

[Figure: see text].

Protease Inhibitor Anti-HIV, Lopinavir, Impairs Placental Endocrine Function.

Protease Inhibitors (PI e.g., ritonavir (RTV) and lopinavir (LPV)) used to treat pregnant mothers infected by HIV induce prematurity and endocrine dysfunctions. The maintenance of pregnancy relies on placental hormone production (human Chorionic Gonadotrophin (hCG) and progesterone (P4)). Those functions are ensured by the villous trophoblast and are mainly regulated by the Unfolded Protein Response (UPR) pathway and mitochondria. We investigated, in vitro, if PI impair hCG and P4 production and the potential intracellular mechanisms involved. Term villous cytotrophoblast (VCT) were cultured with or without RTV or LPV from 6 to 48 h. VCT differentiation into syncytiotrophoblast (ST) was followed measuring hCG and P4 secretion. We evaluated the expression of P4 synthesis partners (Metastatic Lymph Node 64 (MLN64), cholesterol side-chain cleavage (P450SCC), Hydroxy-delta-5-Steroid Dehydrogenase and 3 Beta-and steroid delta-isomerase 1 (HSD3B1)), of mitochondrial pro-fusion factors (Mitofusin 2 (Mfn2), Optic Atrophy 1 (OPA1)) and of UPR factors (Glucose-Regulated Protein 78 (GRP78), Activating Transcription Factor 4 (ATF4), Activating Transcription Factor 6 (ATF6), spliced X-box Binding Protein 1 (sXBP1)). RTV had no significant effect on hCG and P4 secretion, whereas lopinavir significantly decreased both secretions. LPV also decreased P450SCC and HSD3B1 expression, whereas it increased Mfn2, GRP78 and sXBP1 expression in ST. RTV has no effect on the endocrine placenta. LPV impairs both villous trophoblast differentiation and P4 production. It is likely to act via mitochondrial fusion and UPR pathway activation. These trophoblastic alterations may end in decreased P4 levels in maternal circulation, inducing prematurity.

Placenta-Specific Genes, Their Regulation During Villous Trophoblast Differentiation and Dysregulation in Preterm Preeclampsia

The human placenta maintains pregnancy and supports the developing fetus by providing nutrition, gas-waste exchange, hormonal regulation, and an immunological barrier from the maternal immune system. The villous syncytiotrophoblast carries most of these functions and provides the interface between the maternal and fetal circulatory systems. The syncytiotrophoblast is generated by the biochemical and morphological differentiation of underlying cytotrophoblast progenitor cells. The dysfunction of the villous trophoblast development is implicated in placenta-mediated pregnancy complications. Herein, we describe gene modules and clusters involved in the dynamic differentiation of villous cytotrophoblasts into the syncytiotrophoblast. During this process, the immune defense functions are first established, followed by structural and metabolic changes, and then by peptide hormone synthesis. We describe key transcription regulatory molecules that regulate gene modules involved in placental functions. Based on transcriptomic evidence, we infer how villous trophoblast differentiation and functions are dysregulated in preterm preeclampsia, a life-threatening placenta-mediated obstetrical syndrome for the mother and fetus. In the conclusion, we uncover the blueprint for villous trophoblast development and its impairment in preterm preeclampsia, which may aid in the future development of non-invasive biomarkers for placental functions and early identification of women at risk for preterm preeclampsia as well as other placenta-mediated pregnancy complications.

New Insights Into the Role of Placental Aquaporins and the Pathogenesis of Preeclampsia.

Accumulated evidence suggests that an abnormal placentation and an altered expression of a variety of trophoblast transporters are associated to preeclampsia. In this regard, an abnormal expression of AQP3 and AQP9 was reported in these placentas. Recent data suggests that placental AQPs are not only water channel proteins and that may participate in relevant processes required for a normal placental development, such as cell migration and apoptosis. Recently we reported that a normal expression of AQP3 is required for the migration of extravillous trophoblast (EVT) cells. Thus, alterations in this protein might lead to an insufficient transformation of the maternal spiral arteries resulting in fluctuations of oxygen tension, a potent stimulus for oxidative damage and trophoblast apoptosis. In this context, the increase of oxygen and nitrogen reactive species could nitrate AQP9, producing the accumulation of a non-functional protein affecting the survival of the villous trophoblast (VT). This may trigger the exacerbated release of apoptotic VT fragments into maternal circulation producing the systemic endothelial dysfunction underlying the maternal syndrome. Therefore, our hypothesis is that the alteration in the expression of placental AQPs observed at the end of gestation may take place during the trophoblast stem cell differentiation, disturbing both EVT and VT cells development, or during the VT differentiation and turnover. In both situations, VT is affected and at last the maternal vascular system is activated leading to the clinical manifestations of preeclampsia.

124. Immune-driven polyunsaturated fatty acid (PUFA) metabolism in preeclampsia

Introduction Placental macrophages regulate villous trophoblast differentiation and activity. Disturbance of this well-balanced immune-regulation and a pro-inflammatory cytokine milieu can lead to dysfunctional placentas and preeclampsia. Cluster of differentiation 74 (CD74) downregulation in placental macrophages leads to altered macrophage-trophoblast interaction, a pro-inflammatory status and is involved in preeclampsia. Oxylipins, metabolites derived from polyunsaturated fatty acids (PUFAs), are implicated in the development of preeclampsia. Hypothesis Disturbed pro-inflammatory cytokine milieu activates a dysregulated PUFA metabolism enzyme expression pattern leading to disturbed oxylipin levels that can be detected in circulation of preeclamptic mothers. Methods A trophoblast-derived cell line (SGHPL-4) and first trimester villous explants were stimulated by the pro-inflammatory cytokines TNFa, CCL5 and MCP-1. Furthermore, we analyzed placental expression pattern of cytochrome P450 epoxygenases, cyclooxygenases and lipoxygenases by microarray and qRT-PCR from human cohorts and analyzed serum from preeclamptic and uneventful pregnancies by mass spectrometry. Results Microarray studies of preeclamptic placentas revealed a distinguished expression pattern of PUFA metabolism enzymes. Results could be confirmed on two different cohorts (qRT-PCR). Stimulation of SGHPL-4 and villous explants by the pro-inflammatory cytokines TNFa, CCL5 and MCP-1 resulted in similar expression pattern. Oxylipins were dysregulated in the circulation of preeclamptic women compared to uneventful pregnancies atgestational week 28 and week 9–12. Composition of oxylipins at week 9–12 in women that later develop preeclampsia showed a good ROC predictive performance with an AUC = 0.8. Conclusion The pro-inflammatory cytokine milieu induced by the disturbed macrophage-trophoblast interaction induces a distinguished PUFA metabolism leading to dysregulated oxylipins that can predict preeclampsia before onset of clinical symptoms.

The trophoblast survival capacity in preeclampsia.

BackgroundPreeclampsia has become the world’s major maternal health problem putting a huge burden on mothers, newborns and also on the health systems. The pathogenesis of preeclampsia seems to include events in very early pregnancy affecting differentiation of placental villous trophoblast. The arising changes of the cell death spectrum from apoptosis via increased autophagy and aponecrosis to necrosis in turn induce systemic inflammation of the mother.MethodsPlacental tissue samples and maternal serum samples from 40 pregnant women were collected from normal pregnancy, IUGR, early-onset and late-onset preeclampsia. Immunohistochemistry for LC3B and Beclin-1 was quantified using systematic random sampling techniques. Serum levels of LDH and other markers were assessed in serum.ResultsExpression of the autophagy markers LC3B and Beclin-1 was significantly different between groups as was the LC3B/Beclin-1 ratio. Early-onset preeclampsia and IUGR had the highest autophagy protein expression levels, while normal pregnancy and late-onset preeclampsia had the highest LC3B/Beclin-1 ratio. Early-onset preeclampsia had the highest negative correlation with free LDH as cell defect marker.ConclusionsAutophagy plays a critical role in the cell death spectrum and cellular survival capacity of villous trophoblast. Alterations in autophagic protein expression are involved in pathological pregnancies such as preeclampsia.

Punicalagin promotes human villous trophoblast differentiation

Poor differentiation of trophoblasts is associated with placental dysfunction, predisposing women to multiple pregnancy disorders. Punicalagin, a prominent ellagitannin in pomegranate juice has been shown to exert anti-apoptosis and anti-oxidative effects in human trophoblasts. We hypothesized that punicalagin modulates trophoblast differentiation. We found that punicalagin-treated primary trophoblast showed reduced E-cadherin, higher Syncytin 1, more β−hCG, and increased GCM1, an upstream regulator of β−hCG. Punicalagin exposure of villous explants enhanced the number of cytotrophoblasts expressing the proliferation marker Ki67. We conclude that punicalagin enhances trophoblast differentiation and speculate that punicalagin might be used therapeutically in pregnancies at risk for placental dysfunction.

CD74-dysregulation of placental macrophage-trophoblastic interactions in preeclampsia

Rationale: MWe hypothesized that Cluster of differentiation 74 (CD74) downregulation on placental macrophages, leading to altered macrophage-trophoblast interaction, is involved in preeclampsia. Objective: Preeclamptic pregnancies feature hypertension, proteinuria and placental anomalies. Feto-placental macrophages regulate villous trophoblast differentiation during placental development. Disturbance of this well-balanced regulation can lead to pathological pregnancies. Methods and Results: We performed whole genome expression analysis of placental tissue. CD74 was one of the most downregulated genes in placentas from preeclamptic women. By RT-PCR, we confirmed this finding in early onset (<34 gestational week, n=26) and late onset (≥34 gestational week, n=24) samples from preeclamptic women, compared to healthy pregnant controls (n=28). CD74 protein levels were analyzed by Western blot and flow cytometry. We identified placental macrophages to express CD74 by immunofluorescence, flow cytometry and RT-PCR. CD74-positive macrophages were significantly reduced in preeclamptic placentas compared to controls. CD74-silenced macrophages showed that the adhesion molecules ALCAM, ICAM4, and Syndecan-2, as well as macrophage adhesion to trophoblasts were diminished. Naive and activated macrophages lacking CD74 showed a shift towards a pro-inflammatory signature with an increased secretion of TNF , CCL5, and MCP-1, when co-cultured with trophoblasts compared to control macrophages. Trophoblasts stimulated by these factors express more CYP2J2, sFlt1, TNF and IL-8. CD74-knockout mice showed disturbed placental morphology, reduced junctional zone, smaller placentas and impaired spiral artery remodeling with fetal growth restriction. Conclusions: CD74 downregulation in placental macrophages is present in preeclampsia. CD74 downregulation leads to altered macrophage activation towards a pro-inflammatory signature and a disturbed crosstalk with trophoblasts.

CD74-Downregulation of Placental Macrophage-Trophoblastic Interactions in Preeclampsia.

We hypothesized that cluster of differentiation 74 (CD74) downregulation on placental macrophages, leading to altered macrophage-trophoblast interaction, is involved in preeclampsia. Preeclamptic pregnancies feature hypertension, proteinuria, and placental anomalies. Feto-placental macrophages regulate villous trophoblast differentiation during placental development. Disturbance of this well-balanced regulation can lead to pathological pregnancies. We performed whole-genome expression analysis of placental tissue. CD74 was one of the most downregulated genes in placentas from preeclamptic women. By reverse transcriptase-polymerase chain reaction, we confirmed this finding in early-onset (<34 gestational week, n=26) and late-onset (≥34 gestational week, n=24) samples from preeclamptic women, compared with healthy pregnant controls (n=28). CD74 protein levels were analyzed by Western blot and flow cytometry. We identified placental macrophages to express CD74 by immunofluorescence, flow cytometry, and RT-PCR. CD74-positive macrophages were significantly reduced in preeclamptic placentas compared with controls. CD74-silenced macrophages showed that the adhesion molecules ALCAM, ICAM4, and Syndecan-2, as well as macrophage adhesion to trophoblasts were diminished. Naive and activated macrophages lacking CD74 showed a shift toward a proinflammatory signature with an increased secretion of tumor necrosis factor-α, chemokine (C-C motif) ligand 5, and monocyte chemotactic protein-1, when cocultured with trophoblasts compared with control macrophages. Trophoblasts stimulated by these factors express more CYP2J2, sFlt1, TNFα, and IL-8. CD74-knockout mice showed disturbed placental morphology, reduced junctional zone, smaller placentas, and impaired spiral artery remodeling with fetal growth restriction. CD74 downregulation in placental macrophages is present in preeclampsia. CD74 downregulation leads to altered macrophage activation toward a proinflammatory signature and a disturbed crosstalk with trophoblasts.

Abstract 042: Cd74-dysregulation of Macrophage-trophoblastic Interactions in the Preeclamptic Placenta

Objectives: Preeclamptic pregnancies feature placental anomalies. Villous trophoblast differentiation during placental development is regulated by feto-placental macrophages and disturbance of this well-balanced regulation can lead to pathological pregnancies. We hypothesized that Cluster of differentiation 74 (CD74) dysregulation of placental macrophages, leading to altered macrophage-trophoblast interaction, is involved in preeclampsia. Methods and Results: We performed microarray analysis of placental tissue. CD74 was one of the most down-regulated (-2.5 fold) genes in placentas from preeclamptic women. We confirmed this finding in early onset (&lt;34 gestational week, n=26) and late onset (≥34 gestational week, n=24) samples from preeclamptic women, compared to healthy pregnant controls (n=28) by real-time RT-PCR and on protein level by Western blot and flow cytometry. We localized CD74 expression in placental macrophages by immunofluorescence, flow cytometry, and real-time RT-PCR. Number and mean fluorescence intensity (MFI) of CD74-positive macrophages were significantly lower in preeclamptic placentas (7692 MFI ± 4402), as compared to controls (16283 MFI ± 3047). In CD74-silenced macrophages, expression of adhesion molecules ALCAM (-2 fold), ICAM4 (-2.1 fold), and Syndecan-2 (-1.9 fold) was lower compared to control. Macrophage adhesion to a trophoblast layer were diminished (-1.3 fold). Naïve and activated macrophages lacking CD74 showed a shift towards a pro-inflammatory signature with an increased secretion of TNFalpha(21.8 pg/ml ± 13.2 vs. 8 pg/ml ± 4.3), CCL5 (1.9 ng/ml ± 0.4 vs. 0.8 ng/ml ± 0.2) and MCP-1 (3 ng/ml ± 2.6 vs. 1 ng/ml ± 0.5), when co-cultured with trophoblasts compared to control macrophages. CD74-knockout mice showed disturbed placental morphology, reduced junctional zone (1.6 mm2 ± 0.3 vs. 2.3 mm2 ± 0.5) and smaller placentas (0.09 g ± 0.01 vs. 0.11 g ± 0.02) with fetal growth restriction (0.7 g ± 0.1 vs. 0.9 g ± 0.2) when compared to WT mice. Conclusions: We found that CD74 downregulation in placental macrophages is present in preeclampsia. CD74 downregulation led to altered macrophage activation towards a pro-inflammatory signature, a disturbed crosstalk with trophoblasts and an abnormal placental morphology.

Placental melatonin system is present throughout pregnancy and regulates villous trophoblast differentiation.

Melatonin is highly produced in the placenta where it protects against molecular damage and cellular dysfunction arising from hypoxia/re-oxygenation-induced oxidative stress as observed in primary cultures of syncytiotrophoblast. However, little is known about melatonin and its receptors in the human placenta throughout pregnancy and their role in villous trophoblast development. The purpose of this study was to determine melatonin-synthesizing enzymes, arylalkylamine N-acetyltransferase (AANAT) and hydroxyindole O-methyltransferase (HIOMT), and melatonin receptors (MT1 and MT2) expression throughout pregnancy as well as the role of melatonin and its receptors in villous trophoblast syncytialization. Our data show that the melatonin generating system is expressed throughout pregnancy (from week 7 to term) in placental tissues. AANAT and HIOMT show maximal expression at the 3rd trimester of pregnancy. MT1 receptor expression is maximal at the 1st trimester compared to the 2nd and 3rd trimesters, while MT2 receptor expression does not change significantly during pregnancy. Moreover, during primary villous cytotrophoblast syncytialization, MT1 receptor expression increases, while MT2 receptor expression decreases. Treatment of primary villous cytotrophoblast with an increasing concentration of melatonin (10 pM-1 mM) increases the fusion index (syncytium formation; 21% augmentation at 1 mM melatonin vs. vehicle) and β-hCG secretion (121% augmentation at 1 mM melatonin vs. vehicle). This effect of melatonin appears to be mediated via its MT1 and MT2 receptors. In sum, melatonin machinery (synthetizing enzymes and receptors) is expressed in human placenta throughout pregnancy and promotes syncytium formation, suggesting an essential role of this indolamine in placental function and pregnancy well-being.

Drug transporter expression during in vitro differentiation of first-trimester and term human villous trophoblasts

Drug transporters interfere with drug disposition during pregnancy by actively transporting drugs from mother to fetus, and vice versa. Data on their placental expression are scarce, especially during the first trimester of pregnancy. The aim of our study was to assess mRNA expression of more than 80 drug transporters by using an RT-qPCR array in primary cytotrophoblastic cells isolated from first-trimester and term human placentas and cultured for 72 h to form syncytiotrophoblasts. This original expression panel of human placental drug transporters should help to understand transplacental drug transfer and to ensure more rational drug use during pregnancy.

Effect of microcystin-LR on human placental villous trophoblast differentiationin vitro

Microcystin-LR is a cyanobacterial toxin found in surface and recreational waters that inhibits protein phosphatases and may disrupt the cytoskeleton. Microcystins induce apoptosis in hepatocytes at ≤ 2.0 µM. Nothing is known about the effects of microcystins on human placental trophoblast differentiation and function. The differentiation of villous trophoblasts to form syncytiotrophoblast occurs throughout pregnancy and is essential for normal placental and fetal development. To investigate the effects of microcystin, villous cytotrophoblasts were isolated from term placentas using an established method and exposed to microcystin-LR. Microcystin-LR below the cytotoxic dose of 25 µM did not cause cell rounding or detachment, had no effect on apoptosis, and no effect on the morphological differentiation of mononucleated cytotrophoblasts to multinucleated syncytiotrophoblast. However, secretion of human chorionic gonadotropin (hCG) increased in a microcystin-LR dose-dependent manner. When incubated with l-buthionine sulphoximine (BSO) to deplete glutathione levels, trophoblast morphological differentiation proceeded normally in the presence of microcystin-LR. Microcystin-LR did not disrupt the trophoblast microtubule cytoskeleton, which is known to play a role in trophoblast differentiation. Immunofluorescence studies showed that trophoblasts express organic anion transport protein 1B3 (OATP1B3), a known microcystin transport protein. In comparison to hepatocytes, trophoblasts appear to be more resistant to the toxic effects of microcystin-LR. The physiological implications of increased hCG secretion in response to microcystin-LR exposure remain to be determined.

Expression of placental melatonin system during pregnancy and its role in the differentiation of villous trophoblast

Expression of placental melatonin system during pregnancy and its role in the differentiation of villous trophoblast

Comparative expression of lysyl oxidases in early and late first trimester placentas and their implication in villous trophoblast differentiation

Comparative expression of lysyl oxidases in early and late first trimester placentas and their implication in villous trophoblast differentiation