Low oxygen enhances trophoblast column growth by potentiating the extravillous lineage and promoting LOX activity

ABSTRACTEarly placental development and the establishment of the invasive trophoblast lineage take place within a low oxygen environment. However, conflicting and inconsistent findings have obscured the role of oxygen in regulating invasive trophoblast differentiation. In this study, the effect of hypoxic, normoxic, and atmospheric oxygen on invasive extravillous pathway progression was examined using a human placental explant model. Here, we show that exposure to low oxygen enhances extravillous column outgrowth and promotes the expression of genes that align with extravillous trophoblast (EVT) lineage commitment. By contrast, super-physiological atmospheric levels of oxygen promote trophoblast proliferation while simultaneously stalling EVT progression. Low oxygen-induced EVT differentiation coincided with elevated transcriptomic levels of lysyl oxidase (LOX) in trophoblast anchoring columns, where functional experiments established a role for LOX activity in promoting EVT column outgrowth. The findings of this work support a role for low oxygen in potentiating the differentiation of trophoblasts along the extravillous pathway. Additionally, these findings generate insight into new molecular processes controlled by oxygen during early placental development.Summary StatementLow oxygen promotes extravillous trophoblast differentiation

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Trophoblast lineage specification, differentiation and their regulation by oxygen tension

Journal of Endocrinology ◽

10.1530/joe-17-0402 ◽

2018 ◽

Vol 236 (1) ◽

pp. R43-R56 ◽

Cited By ~ 24

Author(s):

Ching-Wen Chang ◽

Anna K Wakeland ◽

Mana M Parast

Keyword(s):

Oxygen Tension ◽

First Trimester ◽

Arterial Blood Flow ◽

Extravillous Trophoblast ◽

Low Oxygen ◽

Epithelial Stem Cells ◽

Placental Development ◽

Trophoblast Differentiation ◽

Arterial Blood ◽

Low Oxygen Tension

Development of the early embryo takes place under low oxygen tension. Under such conditions, the embryo implants and the trophectoderm, the outer layer of blastocyst, proliferate, forming the cytotrophoblastic shell, the early placenta. The cytotrophoblasts (CTBs) are the so-called epithelial ‘stem cells’ of the placenta, which, depending on the signals they receive, can differentiate into either extravillous trophoblast (EVT) or syncytiotrophoblast (STB). EVTs anchor the placenta to the uterine wall and remodel maternal spiral arterioles in order to provide ample blood supply to the growing fetus. STBs arise through CTB fusion, secrete hormones necessary for pregnancy maintenance and form a barrier across which nutrient and gas exchange can take place. The bulk of EVT differentiation occurs during the first trimester, before the onset of maternal arterial blood flow into the intervillous space of the placenta, and thus under low oxygen tension. These conditions affect numerous signaling pathways, including those acting through hypoxia-inducible factor, the nutrient sensor mTOR and the endoplasmic reticulum stress-induced unfolded protein response pathway. These pathways are known to be involved in placental development and disease, and specific components have even been identified as directly involved in lineage-specific trophoblast differentiation. Nevertheless, much controversy surrounds the role of hypoxia in trophoblast differentiation, particularly with EVT. This review summarizes previous studies on this topic, with the intent of integrating these results and synthesizing conclusions that resolve some of the controversy, but then also pointing to remaining areas, which require further investigation.

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Effects of adiponectin on human trophoblast invasion

Journal of Endocrinology ◽

10.1677/joe-10-0170 ◽

2010 ◽

Vol 207 (1) ◽

pp. 45-53 ◽

Cited By ~ 38

Author(s):

Delphine Benaitreau ◽

Esther Dos Santos ◽

Marie-Christine Leneveu ◽

Nadia Alfaidy ◽

Jean-Jacques Feige ◽

...

Keyword(s):

First Trimester ◽

Extravillous Trophoblast ◽

Trophoblast Invasion ◽

Placental Development ◽

Independent Manner ◽

Human Trophoblast ◽

Pathological Conditions ◽

First Trimester Of Pregnancy ◽

Insight Into

Adiponectin is an adipokine with insulin-sensitizing, anti-inflammatory, anti-atherogenic, and anti-proliferative effects. The expression of specific adiponectin receptors in the placenta and in the endometrium suggests a role for this cytokine in placental development, but this role has not yet been elucidated. The invasion of trophoblast cells during the first trimester of pregnancy being crucial to placentation process, we have studied adiponectin effects on human trophoblast invasive capacities. We found that adiponectin stimulated human trophoblast cell migration in HTR-8/SVneo cells in a dose-independent manner. In addition, adiponectin also significantly enhanced invasion of HTR-8/SVneo cells and of human extravillous trophoblast from first trimester placenta. These pro-invasive effects of adiponectin in human trophoblasts seem to be mediated in part via increased matrix metalloproteinases (MMP2 and MMP9) activities and via repression of TIMP2 mRNA expression. Our results suggest that adiponectin could be a positive regulator of the early invasion process by modulating the MMP/TIMP balance. Moreover, these results provide an insight into the role of adiponectin in pathological conditions characterized by insufficient or excessive trophoblast invasion.

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Where Polarity Meets Fusion: Role of Par6 in Trophoblast Differentiation during Placental Development and Preeclampsia

Endocrinology ◽

10.1210/en.2012-1823 ◽

2013 ◽

Vol 154 (3) ◽

pp. 1296-1309 ◽

Cited By ~ 12

Author(s):

Tharini Sivasubramaniyam ◽

Julia Garcia ◽

Andrea Tagliaferro ◽

Megan Melland-Smith ◽

Sarah Chauvin ◽

...

Keyword(s):

Tight Junction ◽

Cell Polarity ◽

Cell Fusion ◽

Trophoblast Cell ◽

Placental Development ◽

Trophoblast Differentiation ◽

Cytoskeleton Dynamics ◽

Insight Into ◽

Cells Cultured

Abstract Trophoblast cell fusion is a prerequisite for proper human placental development. Herein we examined the contribution of Par6 (Partitioning defective protein 6), a key regulator of cell polarity, to trophoblast cell fusion in human placental development. During early placentation, Par6 localized to nuclei of cytotrophoblast cells but with advancing gestation Par6 shifted its localization to the cytoplasm and apical brush border of the syncytium. Exposure of primary isolated trophoblasts to 3% O2 resulted in elevated Par6 expression, maintenance of tight junction marker ZO-1 at cell boundaries, and decreased fusogenic syncytin 1 expression compared with cells cultured at 20% O2. Treatment of choriocarcinoma BeWo cells with forskolin, a known inducer of fusion, increased syncytin 1 expression but decreased that of Par6 and ZO-1. Par6 overexpression in the presence of forskolin maintained ZO-1 at cell boundaries while decreasing syncytin 1 levels. In contrast, silencing of Par6 disrupted ZO-1 localization at cell boundaries and altered the expression and distribution of acetylated α-tubulin. Par6 expression was elevated in preeclamptic placentas relative to normotensive preterm controls and Par6 located to trophoblast cells expressing ZO-1. Together, our data indicate that Par6 negatively regulates trophoblast fusion via its roles on tight junctions and cytoskeleton dynamics and provide novel insight into the contribution of this polarity marker in altered trophoblast cell fusion typical of preeclampsia.

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Oxygen regulation of macrophage migration inhibitory factor in human placenta

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00086.2006 ◽

2007 ◽

Vol 292 (1) ◽

pp. E272-E280 ◽

Cited By ~ 23

Author(s):

Francesca Ietta ◽

Yuanhong Wu ◽

Roberta Romagnoli ◽

Nima Soleymanlou ◽

Barbara Orsini ◽

...

Keyword(s):

High Altitude ◽

Migration Inhibitory Factor ◽

Macrophage Migration Inhibitory Factor ◽

Inhibitory Factor ◽

Extravillous Trophoblast ◽

Macrophage Migration ◽

Low Oxygen ◽

Placental Development

Macrophage migration inhibitory factor (MIF) is an important proinflammatory cytokine involved in regulation of macrophage function. In addition, MIF may also play a role in murine and human reproduction. Although both first trimester trophoblast and decidua express MIF, the regulation and functional significance of this cytokine during human placental development remains unclear. We assessed MIF expression throughout normal human placental development, as well as in in vitro (chorionic villous explants) and in vivo (high altitude placentae) models of human placental hypoxia. Dimethyloxalylglycine (DMOG), which stabilizes hypoxia inducible factor-1 under normoxic conditions, was also used to mimic the effects of hypoxia on MIF expression. Quantitative real-time PCR and Western blot analysis showed high MIF protein and mRNA expression at 7–10 wk and lower levels at 11–12 wk until term. Exposure of villous explants to 3% O2 resulted in increased MIF expression and secretion relative to standard conditions (20% O2). DMOG treatment under 20% O2 increased MIF expression. In situ hybridization and immunohistochemistry showed elevated MIF expression in low oxygen-induced extravillous trophoblast cells. Finally, a significant increase in MIF transcript was observed in placental tissues from high-altitude pregnancies. Hence, three experimental models of placental hypoxia (early gestation, DMOG treatment, and high altitude) converge in stimulating increased MIF, supporting the conclusion that placental-derived MIF is an oxygen-responsive cytokine highly expressed in physiological in vivo and in in vitro low oxygen conditions.

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Trophectoderm-Specific Knockdown of LIN28 Decreases Expression of Genes Necessary for Cell Proliferation and Reduces Elongation of Sheep Conceptus

International Journal of Molecular Sciences ◽

10.3390/ijms21072549 ◽

2020 ◽

Vol 21 (7) ◽

pp. 2549 ◽

Cited By ~ 1

Author(s):

Asghar Ali ◽

Mark Stenglein ◽

Thomas Spencer ◽

Gerrit Bouma ◽

Russell Anthony ◽

...

Keyword(s):

Cell Proliferation ◽

Critical Period ◽

In Vitro Experiments ◽

Placental Development ◽

Expression Of Genes ◽

Trophectoderm Cells ◽

Successful Establishment

LIN28 inhibits let-7 miRNA maturation which prevents cell differentiation and promotes proliferation. We hypothesized that the LIN28-let-7 axis regulates proliferation-associated genes in sheep trophectoderm in vivo. Day 9-hatched sheep blastocysts were incubated with lentiviral particles to deliver shRNA targeting LIN28 specifically to trophectoderm cells. At day 16, conceptus elongation was significantly reduced in LIN28A and LIN28B knockdowns. Let-7 miRNAs were significantly increased and IGF2BP1-3, HMGA1, ARID3B, and c-MYC were decreased in trophectoderm from knockdown conceptuses. Ovine trophoblast (OTR) cells derived from day 16 trophectoderm are a useful tool for in vitro experiments. Surprisingly, LIN28 was significantly reduced and let-7 miRNAs increased after only a few passages of OTR cells, suggesting these passaged cells represent a more differentiated phenotype. To create an OTR cell line more similar to day 16 trophectoderm we overexpressed LIN28A and LIN28B, which significantly decreased let-7 miRNAs and increased IGF2BP1-3, HMGA1, ARID3B, and c-MYC compared to control. This is the first study showing the role of the LIN28-let-7 axis in trophoblast proliferation and conceptus elongation in vivo. These results suggest that reduced LIN28 during early placental development can lead to reduced trophoblast proliferation and sheep conceptus elongation at a critical period for successful establishment of pregnancy.

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The Role of heat shock protein 27 in extravillous trophoblast differentiation

Journal of Cellular Biochemistry ◽

10.1002/jcb.21476 ◽

2008 ◽

Vol 103 (3) ◽

pp. 719-729 ◽

Cited By ~ 18

Author(s):

S. Tartakover Matalon ◽

L. Drucker ◽

A. Fishman ◽

A. Ornoy ◽

M. Lishner

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Heat Shock Protein 27 ◽

Extravillous Trophoblast ◽

Trophoblast Differentiation

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Fetal and trophoblast PI3Kp110α have distinct roles in regulating resource supply to the growing fetus

10.1101/473967 ◽

2018 ◽

Author(s):

Jorge Lopez-Tello ◽

Vicente Perez-Garcia ◽

Jaspreet Khaira ◽

Laura C. Kusinski ◽

Wendy N. Cooper ◽

...

Keyword(s):

Fetal Growth ◽

Embryonic Stem ◽

Prenatal Development ◽

Complete Loss ◽

Placental Development ◽

Expression Of Genes ◽

Transport Loss ◽

Healthy Growth ◽

Phosphoinositide 3 Kinase

AbstractPrevious studies suggest that the placental supply of nutrients to the fetus adapts according to fetal demand. However, the signaling events underlying placental adaptations remain largely unknown. Earlier work in mice has revealed that loss of the phosphoinositide 3-kinase p110α impairs feto-placental growth but placental nutrient supply is adaptively increased. Here we explore the role of p110α in the epiblast-derived (fetal) and trophoblast lineages of the conceptus in relation to feto-placental growth and placental development and transfer function. Using conditional gene manipulations to knock-down p110α either by ∼50% or ∼100% in the fetal lineages and/or trophoblast, this study shows that p110α in the fetus is essential for prenatal development and a major regulator of placental phenotype in mice. Complete loss of fetal p110α caused embryonic death, whilst heterozygous loss resulted in fetal growth restriction and impaired placental formation and nutrient transport. Loss of trophoblast p110α also resulted in abnormal placental development, although fetuses were viable. However, in response to complete loss of trophoblast p110α, the placenta failed to transport sufficient amino acid to match fetal demands for growth. Using RNA-seq, we identified several genes downstream of p110α in the trophoblast that are important in adapting placental phenotype to support fetal growth. Further work using CRISPR/Cas9 genome targeting showed that loss of p110α differentially affects the expression of genes in trophoblast and embryonic stem cells. Our findings thus reveal important, but distinct roles for p110α signaling in the different compartments of the conceptus, which control fetal resource acquisition and ultimately affect healthy growth.One Sentence SummaryFetal and trophoblast p110α modify resource allocation

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Role of biochemical factors in the pathogenesis of keratoconus.

Acta Biochimica Polonica ◽

10.18388/abp.2014_1923 ◽

2014 ◽

Vol 61 (1) ◽

Cited By ~ 22

Author(s):

Katarzyna A Wojcik ◽

Janusz Blasiak ◽

Jerzy Szaflik ◽

Jacek P Szaflik

Keyword(s):

Lysyl Oxidase ◽

Interleukin 1 ◽

Covalent Bonds ◽

Altered Expression ◽

Expression Of Genes ◽

Nitrative Stress ◽

Structural Abnormalities ◽

Increased Activity ◽

Increased Susceptibility

Keratoconus (KC) is a corneal disease associated with structural abnormalities in the corneal epithelium, Bowman's layer and stroma and altered concentration of tear components. KC corneas show a different pattern of collagen lamellae than their normal counterparts. Also, a reduction of several collagen types in KC epithelium and stroma was observed. Altered expression and/or activity of lysyl oxidase, a critical enzyme of the biogenesis of connective tissue detected in KC corneas, may weaken covalent bonds between collagen and elastin fibrils, what may lead to biomechanical deterioration of the cornea. Increased activity of matrix metalloproteinases observed in KC may induce the degradation of the extracellular matrix causing damage to the cornea. Oxidative and nitrative stress play an important role in KC pathogenesis and KC corneas are characterized by the disturbed lipid peroxidation and nitric oxide pathways. Malfunctioning of these pathways may lead to accumulation of their toxic by-products inducing several detrimental effects, along with apoptosis of the corneal cells, which may result from the loss of β-actin or increased levels of cytokines, including interleukin-1 and -6. Change in the expression of genes associated with wound healing, including the nerve growth factor and the visual system homeobox 1, may contribute to increased susceptibility of KC corneas to injury. Consequently, biochemical changes may play an important role in KC pathophysiology and, therefore, can be considered in prevention, diagnosis, prognosis and in the therapy of this disease as well.

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Peptide hormone ELABELA enhances extravillous trophoblast differentiation, but placenta is not the major source of circulating ELABELA in pregnancy

Scientific Reports ◽

10.1038/s41598-019-55650-5 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Danai Georgiadou ◽

Souad Boussata ◽

Willemijn H. M. Ranzijn ◽

Leah E. A. Root ◽

Sanne Hillenius ◽

...

Keyword(s):

Ex Vivo ◽

Peptide Hormone ◽

First Trimester ◽

Extravillous Trophoblast ◽

Hypertensive Disorder ◽

Trophoblast Differentiation ◽

Large Variability ◽

Apelin Receptor

AbstractPreeclampsia is a frequent gestational hypertensive disorder with equivocal pathophysiology. Knockout of peptide hormone ELABELA (ELA) has been shown to cause preeclampsia-like symptoms in mice. However, the role of ELA in human placentation and whether ELA is involved in the development of preeclampsia in humans is not yet known. In this study, we show that exogenous administration of ELA peptide is able to increase invasiveness of extravillous trophoblasts in vitro, is able to change outgrowth morphology and reduce trophoblast proliferation ex vivo, and that these effects are, at least in part, independent of signaling through the Apelin Receptor (APLNR). Moreover, we show that circulating levels of ELA are highly variable between women, correlate with BMI, but are significantly reduced in first trimester plasma of women with a healthy BMI later developing preeclampsia. We conclude that the large variability and BMI dependence of ELA levels in circulation make this peptide an unlikely candidate to function as a first trimester preeclampsia screening biomarker, while in the future administering ELA or a derivative might be considered as a potential preeclampsia treatment option as ELA is able to drive extravillous trophoblast differentiation.

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Hypoxia-Inducible Factor in Thyroid Carcinoma

Journal of Thyroid Research ◽

10.4061/2011/762905 ◽

2011 ◽

Vol 2011 ◽

pp. 1-17 ◽

Cited By ~ 24

Author(s):

Natalie Burrows ◽

Muhammad Babur ◽

Julia Resch ◽

Kaye J. Williams ◽

Georg Brabant

Keyword(s):

Thyroid Carcinoma ◽

Potential Role ◽

Hypoxia Inducible Factor ◽

Current Data ◽

Low Oxygen ◽

Expression Of Genes ◽

Mitogen Activated Protein ◽

Growth Factor Signalling ◽

Pi3k Signalling

Intratumoural hypoxia (low oxygen tension) is associated with aggressive disease and poor prognosis. Hypoxia-inducible factor-1 is a transcription factor activated by hypoxia that regulates the expression of genes that promote tumour cell survival, progression, metastasis, and resistance to chemo/radiotherapy. In addition to hypoxia, HIF-1 can be activated by growth factor-signalling pathways such as the mitogen-activated protein kinases- (MAPK-) and phosphatidylinositol-3-OH kinases- (PI3K-) signalling cascades. Mutations in these pathways are common in thyroid carcinoma and lead to enhanced HIF-1 expression and activity. Here, we summarise current data that highlights the potential role of both hypoxia and MAPK/PI3K-induced HIF-1 signalling in thyroid carcinoma progression, metastatic characteristics, and the potential role of HIF-1 in thyroid carcinoma response to radiotherapy. Direct or indirect targeting of HIF-1 using an MAPK or PI3K inhibitor in combination with radiotherapy may be a new potential therapeutic target to improve the therapeutic response of thyroid carcinoma to radiotherapy and reduce metastatic burden.

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