Microvillous membrane potential (E m) in villi from first trimester human placenta: comparison toE m at term

1997 ◽  
Vol 273 (4) ◽  
pp. R1519-R1528 ◽  
Author(s):  
T. J. Birdsey ◽  
R. D. H. Boyd ◽  
C. P. Sibley ◽  
S. L. Greenwood
Keyword(s):  
Membrane Potential ◽  
Human Placenta ◽  
First Trimester ◽  
Major Contributor ◽  
Placental Development ◽  
Ion Conductance ◽  
Placental Villi

The microvillous membrane (MVM) potential ( E m) of first trimester human placental villi was measured and compared with that in villi from term human placentas. The median E m in first trimester villi (−28 mV) was significantly more negative than that at term (−21 mV; P < 0.001). The median E m measured in villi from early ( weeks 6–11) first trimester (−32 mV) was significantly more negative than that in late ( weeks 12 and 13) first trimester villi (−24 mV; P < 0.001). Elevating extracellular KCl concentration induced a significant depolarization of E m in both first trimester and term villi ( P < 0.05 and P < 0.001, respectively). The magnitude of this depolarization was greater in first trimester than at term, indicating that the ion conductance of the MVM changes with gestation. Exposure to ouabain induced a significant depolarization of E m (3 mV: P < 0.05) in first trimester villi but had little effect at term. These results suggest that microvillous membrane electrophysiology changes with placental development. An alteration in the relative K+:Cl−conductance of the MVM is likely to be a major contributor to the change in the magnitude of E m.

scholarly journals Proteome Profiling of Human Placenta Reveals Developmental Stage-Dependent Alterations in Protein Signature

2021 ◽  
Author(s):  
Sara Khorami Sarvestani ◽  
Sorour Shojaeian ◽  
Negar Vanaki ◽  
Behrouz Gharesi-Fard ◽  
Mehdi Amini ◽  
...  
Keyword(s):  
Human Placenta ◽  
First Trimester ◽  
Full Term ◽  
Chemical Stimulus ◽  
Health It ◽  
Low Oxygen ◽  
Placental Development ◽  
Liquid Chromatography Tandem Mass ◽  
Complex Organ ◽  
Protein Signature

Abstract Introduction Placenta is a complex organ that plays a significant role in the maintenance of pregnancy health. It is a dynamic organ that undergoes dramatic changes in growth and development at different stages of gestation. In the first-trimester, the conceptus develops in a low oxygen environment that favors organogenesis in the embryo and cell proliferation and angiogenesis in the placenta; later in pregnancy, higher oxygen concentration is required to support the rapid growth of the fetus. This transition, which appears unique to the human placenta, must be finely tuned through successive rounds of protein signature alterations. This study compares placental proteome in normal first-trimester (FT) and term human placentas (TP). MethodsNormal human first-trimester and term placental samples were collected and differentially expressed proteins were identified using two-dimensional liquid chromatography-tandem mass spectrometry.ResultsDespite the overall similarities, 120 proteins were differently expressed in first and term placentas. Out of these, 120 proteins, expression of 72 was up-regulated and that of 48 was down-regulated in the first when compared with the full term placentas. Twenty out of 120 differently expressed proteins were sequenced, among them seven showed increased (GRP78, PDIA3, ENOA, ECH1, PRDX4, ERP29, ECHM), eleven decreased (TRFE, ALBU, K2C1, ACTG, CSH2, PRDX2, FABP5, HBG1, FABP4, K2C8, K1C9) expression in first-trimester compared to the full-term placentas and two proteins exclusively expressed in first-trimester placentas (MESD, MYDGF). DiscussionAccording to Reactome and PANTHER softwares, these proteins were mostly involved in response to chemical stimulus and stress, regulation of biological quality, programmed cell death, hemostatic and catabolic processes, protein folding, cellular oxidant detoxification, coagulation and retina homeostasis. Elucidation of alteration in protein signature during placental development would provide researchers with a better understanding of the critical biological processes of placentogenesis and delineate proteins involved in regulation of placental function during development.

scholarly journals The first trimester human placenta is a site for terminal maturation of primitive erythroid cells

Blood ◽  
2010 ◽  
Vol 116 (17) ◽  
pp. 3321-3330 ◽  
Author(s):  
Ben Van Handel ◽  
Sacha L. Prashad ◽  
Nargess Hassanzadeh-Kiabi ◽  
Andy Huang ◽  
Mattias Magnusson ◽  
...  
Keyword(s):  
Human Placenta ◽  
Blood Cells ◽  
Fetal Liver ◽  
First Trimester ◽  
Erythroid Cells ◽  
Chorionic Plate ◽  
Placental Villi ◽  
Placental Macrophages ◽  
A Site ◽  
Broad Role

Abstract Embryonic hematopoiesis starts via the generation of primitive red blood cells (RBCs) that satisfy the embryo's immediate oxygen needs. Although primitive RBCs were thought to retain their nuclei, recent studies have shown that primitive RBCs in mice enucleate in the fetal liver. It has been unknown whether human primitive RBCs enucleate, and what hematopoietic site might support this process. Our data indicate that the terminal maturation and enucleation of human primitive RBCs occurs in first trimester placental villi. Extravascular ζ-globin+ primitive erythroid cells were found in placental villi between 5-7 weeks of development, at which time the frequency of enucleated RBCs was higher in the villous stroma than in circulation. RBC enucleation was further evidenced by the presence of primitive reticulocytes and pyrenocytes (ejected RBC nuclei) in the placenta. Extravascular RBCs were found to associate with placental macrophages, which contained ingested nuclei. Clonogenic macrophage progenitors of fetal origin were present in the chorionic plate of the placenta before the onset of fetoplacental circulation, after which macrophages had migrated to the villi. These findings indicate that placental macrophages may assist the enucleation process of primitive RBCs in placental villi, implying an unexpectedly broad role for the placenta in embryonic hematopoiesis.

scholarly journals Proteome profiling of human placenta reveals developmental stage-dependent alterations in protein signature

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Sara Khorami Sarvestani ◽  
Sorour Shojaeian ◽  
Negar Vanaki ◽  
Behrouz Ghresi-Fard ◽  
Mehdi Amini ◽  
...  
Keyword(s):  
Human Placenta ◽  
First Trimester ◽  
Full Term ◽  
Chemical Stimulus ◽  
Health It ◽  
Low Oxygen ◽  
Placental Development ◽  
Liquid Chromatography Tandem Mass ◽  
Normal Human ◽  
Protein Signature

Abstract Introduction Placenta is a complex organ that plays a significant role in the maintenance of pregnancy health. It is a dynamic organ that undergoes dramatic changes in growth and development at different stages of gestation. In the first-trimester, the conceptus develops in a low oxygen environment that favors organogenesis in the embryo and cell proliferation and angiogenesis in the placenta; later in pregnancy, higher oxygen concentration is required to support the rapid growth of the fetus. This oxygen transition, which appears unique to the human placenta, must be finely tuned through successive rounds of protein signature alterations. This study compares placental proteome in normal first-trimester (FT) and term human placentas (TP). Methods Normal human first-trimester and term placental samples were collected and differentially expressed proteins were identified using two-dimensional liquid chromatography-tandem mass spectrometry. Results Despite the overall similarities, 120 proteins were differently expressed in first and term placentas. Out of these, 72 were up-regulated and 48 were down-regulated in the first when compared with the full term placentas. Twenty out of 120 differently expressed proteins were sequenced, among them seven showed increased (GRP78, PDIA3, ENOA, ECH1, PRDX4, ERP29, ECHM), eleven decreased (TRFE, ALBU, K2C1, ACTG, CSH2, PRDX2, FABP5, HBG1, FABP4, K2C8, K1C9) expression in first-trimester compared to the full-term placentas and two proteins exclusively expressed in first-trimester placentas (MESD, MYDGF). Conclusion According to Reactome and PANTHER softwares, these proteins were mostly involved in response to chemical stimulus and stress, regulation of biological quality, programmed cell death, hemostatic and catabolic processes, protein folding, cellular oxidant detoxification, coagulation and retina homeostasis. Elucidation of alteration in protein signature during placental development would provide researchers with a better understanding of the critical biological processes of placentogenesis and delineate proteins involved in regulation of placental function during development.

scholarly journals Cytological localization of chorionic gonadotropin alpha and placental lactogen mRNAs during development of the human placenta.

1982 ◽  
Vol 93 (1) ◽  
pp. 190-198 ◽  
Author(s):  
M Hoshina ◽  
M Boothby ◽  
I Boime
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Placenta ◽  
First Trimester ◽  
Placental Lactogen ◽  
Mrna Synthesis ◽  
Placental Development ◽  
Trophoblast Differentiation ◽  
Constant Rate ◽  
Alpha Gene ◽  
Cytological Localization

Probes derived from clones bearing cDNAs corresponding to the alpha subunit of human chorionic gonadotropin (hCG) and human placental lactogen (hPL) were used to localize their respective mRNAs cytologically in sections of first trimester and term human placenta. hPL mRNA was exclusively localized to the syncytial layer, hCG alpha mRNA was found in the syncytial layer and also in some differentiating cytotrophoblasts. Hybridization was specific because no signal was observed when labeled pBR322 was hybridized to placental sections or when the placental probes were hybridized to sections of human tonsils. In addition, RNA in placental interstitial cells did not hybridize with hCG alpha and hPL probes. Hybridization with the hCG alpha probe was much greater in first trimester than in term sections, whereas hPL signals were comparable in both first trimester and term placentae. Syncytial formation proceeds through cellular intermediates of cytotrophoblastic origin, and the data suggest that transcription of the hCG alpha gene is initiated before the completion of syncytial formation. In contrast, hPL mRNA synthesis starts later in trophoblast differentiation, likely after the stage of syncytial formation. The data also suggested that hCG alpha mRNA synthesis becomes attenuated but that hPL is transcribed at a rather constant rate during placental development.

scholarly journals HYPOXIA AND REPRODUCTIVE HEALTH: Oxygen and development of the human placenta

Reproduction ◽  
2021 ◽  
Vol 161 (1) ◽  
pp. F53-F65 ◽  
Author(s):  
Graham J Burton ◽  
Tereza Cindrova-Davies ◽  
Hong wa Yung ◽  
Eric Jauniaux
Keyword(s):  
Oxidative Stress ◽  
Human Placenta ◽  
Epithelial Mesenchymal Transition ◽  
First Trimester ◽  
Extravillous Trophoblast ◽  
Low Oxygen ◽  
Placental Development ◽  
Mesenchymal Transition ◽  
Oxygen Concentrations

Development of the human placenta takes place in contrasting oxygen concentrations at different stages of gestation, from ~20 mmHg during the first trimester rising to ~60 mmHg at the start of the second trimester before gradually declining to ~40 mmHg at term. In view of these changes, the early placenta has been described as ‘hypoxic’. However, placental metabolism is heavily glycolytic, supported by the rich supply of glucose from the endometrial glands, and there is no evidence of energy compromise. On the contrary, the trophoblast is highly proliferative, with the physiological low-oxygen environment promoting maintenance of stemness in progenitor populations. These conditions favour the formation of the cytotrophoblastic shell that encapsulates the conceptus and interfaces with the endometrium. Extravillous trophoblast cells on the outer surface of the shell undergo an epithelial-mesenchymal transition and acquire invasive potential. Experimental evidence suggests that these changes may be mediated by the higher oxygen concentration present within the placental bed. Interpreting in vitro data is often difficult, however, due to the use of non-physiological oxygen concentrations and trophoblast-like cell lines or explant models. Trophoblast is more vulnerable to hyperoxia or fluctuating levels of oxygen than to hypoxia, and some degree of placental oxidative stress likely occurs in all pregnancies towards term. In complications of pregnancy, such as early-onset pre-eclampsia, malperfusion generates high levels of oxidative stress, causing release of factors that precipitate the maternal syndrome. Further experiments are required using genuine trophoblast progenitor cells and physiological concentrations to fully elucidate the pathways by which oxygen regulates placental development.

Oxygen governs Galβ1–3GalNAc epitope in human placenta

2013 ◽  
Vol 305 (9) ◽  
pp. C931-C940 ◽  
Author(s):  
Leonardo Ermini ◽  
Jayonta Bhattacharjee ◽  
Antonella Spagnoletti ◽  
Nicoletta Bechi ◽  
Silvia Aldi ◽  
...  
Keyword(s):  
Oxygen Tension ◽  
Human Placenta ◽  
Physiological State ◽  
First Trimester ◽  
Signal Molecules ◽  
Control Mechanisms ◽  
Low Oxygen ◽  
Placental Development ◽  
Human Trophoblast ◽  
Cell Functions

It is becoming increasingly apparent that the dynamics of glycans reflect the physiological state of cells involved in several cell functions including growth, response to signal molecules, migration, as well as adhesion to, interaction with, and recognition of other cells. The presence of glycoconjugates in human placenta suggests their major role in maternal-fetal exchanges, intercellular adhesion, cellular metabolism, and villous vessel branching. Although several studies have described glycoconjugate distribution in the human placenta descriptions of their physiological function and control mechanisms during placental development are lacking. In this study we investigated the developmental distribution and regulation of placental core 1 O- and N-glycans focusing on early and late first trimester human pregnancy. To define the control mechanisms of the oligosaccharide chains during early placentation process, chorionic villous explants and human trophoblast cell lines were exposed to various oxygen levels. We found that oxygen tension regulates changes in core-1 O-glycan (the disaccharide Galβ1–3GalNAc) epitope expression levels. Moreover, by double affinity chromatography and subsequent analysis with mass spectrometry, we identified in the heat shock protein 90-α (HSP90α) a good candidate as carrier of the Galβ1–3GalNAc epitope at low oxygen tension. Our results support a fundamental role of oxygen tension in modulating glycosylation of proteins during placental development.

Endogenous heparin-binding lectin activity in human placenta: purification and developmental expression

1990 ◽  
Vol 68 (4) ◽  
pp. 790-795 ◽  
Author(s):  
Howard Ceri ◽  
Wei Sek Hwang ◽  
Helen Cheung
Keyword(s):  
Human Placenta ◽  
First Trimester ◽  
Cross Reactivity ◽  
Developmental Expression ◽  
Rat Tissues ◽  
Heparin Binding ◽  
Placental Development ◽  
Lectin Activity ◽  
Heparin Affinity ◽  
Binding Lectin

Human placental extracts contain a herapin-inhibitable lectin activity. The lectin, which closely resembles those from chicken and rat tissues, was purified by heparin-affinity chromatography. It shares many properties with the previously reported lectins, including hapten specificity, molecular weight of monomers, and immunological cross-reactivity. Sections from different stages of placental development, stained by immunohistochemistry procedures using lectin-specific antibody, showed that the lectin was initially present only in cytotrophoblasts of early first trimester villi. Later in the first trimester, both cytotrophoblasts and syncytiotrophoblasts were stained positively for lectin. From second trimester to term, the lectin was seen only in syncytiotrophoblasts.Key words: lectin, human placenta, development, heparin, cytotrophoblast, syncytiotrophoblast.

Expression of interleukin-6 (IL-6), signal transducer and activator of transcription-3 (STAT-3) and telomerase in choriocarcinomas

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Luciana Pietro ◽  
Fátima Bottcher-Luiz ◽  
Lício Augusto Velloso ◽  
Joseane Morari ◽  
Marcelo Nomura ◽  
...  
Keyword(s):  
Cell Transformation ◽  
First Trimester ◽  
Bewo Cell ◽  
Placental Development ◽  
Trimester Abortion ◽  
Bewo Cells ◽  
Culture Cells ◽  
Bewo Cell Line ◽  
Blastocyst Implantation ◽  
First Trimester Of Pregnancy

Abstract Blastocyst implantation and neoplastic invasion have some common properties related to tissue invasion, mediated by various cytokines. Aim To compare the expression of IL-6, STAT-3 and telomerase in material of abortions in the first trimester of pregnancy, at term placentas and in choriocarcinomas. Methods Immunohistochemical reactions were performed on formalin fixed and included in paraffin samples from 3 groups: abortions, normal at term placentas and choriocarcinomas. Western Blot and Real-Time PCR assays were performed on fresh material from BeWo cell line and in primary culture cells of normal placenta. Results Immunohistochemical reactions: IL-6 expression was moderate in the first trimester abortion samples and high in at term placentas and choriocarcinomas. STAT-3 was strongly positive in all groups. Telomerase expression was absent in normal at term placentas but was increased in BeWo cells. Conclusion IL-6 and STAT-3 are present in the invasion process of the normal placental development and they are maintained during the malignant transformation to choriocarcinoma. The intense telomerase expression observed in BeWo cells was strongly associated with the malignant phenotype, confirming it as a good marker for cell transformation and tumor progression.

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