scholarly journals Reciprocal expression of 17α-hydroxylase-C17,20-lyase and aromatase cytochrome P450 during bovine trophoblast differentiation: a two-cell system drives placental oestrogen synthesis

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 669-679 ◽  
Author(s):  
G Schuler ◽  
G R Özalp ◽  
B Hoffmann ◽  
N Harada ◽  
P Browne ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Cell Types ◽  
Staining Intensity ◽  
Giant Cells ◽  
Cell System ◽  
Cellular Level ◽  
Specific Staining ◽  
Cytoplasmic Staining ◽  
Distinct Cell ◽  
Trophoblast Giant Cells

No definitive information is yet available on the steroidogenic capacity of the two morphologically distinct cell types forming the bovine trophoblast, the uninucleated trophoblast cells (UTCs) and the trophoblast giant cells (TGCs). Hence, in order to localise 17α-hydroxylase-C17,20-lyase (P450c17) on a cellular level and to monitor its expression as a function of gestational age, placentomes from pregnant (days 80–284; n = 19), prepartal (days 273–282; 24–36 h prior to the onset of labour; n = 3) and parturient cows (n = 5) were immunostained for P450c17 using an antiserum against the recombinant bovine enzyme. At all stages investigated, P450c17 was exclusively found in the UTCs of chorionic villi (CV), where staining was ubiquitous between days 80 and 160, but was largely restricted to primary CV and the branching sites of secondary CV between days 160 and 240. Thereafter, a distinct ubiquitous staining reoccurred in the UTCs of all CV in late pregnant, prepartal and parturient animals. Using an antiserum against human aromatase cytochrome P450 (P450arom), specific cytoplasmic staining was observed in TGCs. In placentomes from pregnant cows, staining intensity was higher in mature compared with immature TGCs and was more pronounced in the trophoblast covering big stem villi compared with the trophoblast at other sites of the villous tree. In placentomes of a parturient cow, specific staining was only found in mature TGCs that survived the normal, but substantial, prepartal decline in TGC numbers. These results clearly showed that bovine UTCs and TGCs exhibit different steroidogenic capacities, constituting a ‘two-cell’ organisation for oestrogen synthesis. P450c17 expression appears to be quickly down-regulated and P450arom is up-regulated when UTCs enter the TGC differentiation pathway.

scholarly journals A molecular mechanism of mouse placental spongiotrophoblast differentiation regulated by prolyl oligopeptidase

Zygote ◽  
2019 ◽  
Vol 27 (1) ◽  
pp. 49-53
Author(s):  
Yuki Maruyama ◽  
Atsushi P. Kimura
Keyword(s):  
Molecular Mechanism ◽  
Critical Role ◽  
Specific Inhibitor ◽  
Cell Types ◽  
Giant Cells ◽  
Akt Pathway ◽  
Prolyl Oligopeptidase ◽  
Trophoblast Stem ◽  
Trophoblast Stem Cell ◽  
Trophoblast Giant Cells

SummaryIn eutherian mammals, the placenta plays a critical role in embryo development by supplying nutrients and hormones and mediating interaction with the mother. To establish the fine connection between mother and embryo, the placenta needs to be formed normally, but the mechanism of placental differentiation is not fully understood. We previously revealed that mouse prolyl oligopeptidase (POP) plays a role in trophoblast stem cell (TSC) differentiation into two placental cell types, spongiotrophoblasts (SpT) and trophoblast giant cells. Here, we focused on SpT differentiation and attempted to elucidate a molecular mechanism. ForAscl2,Arnt, andEgfrgenes that are indispensable for SpT formation, we found that a POP-specific inhibitor, SUAM-14746, significantly decreasedAscl2expression, which was consistent with a significant decrease in expression ofFlt1, a gene downstream ofAscl2. Although this downregulation was unlikely to be mediated by the PI3K-Akt pathway, our results indicated that POP controls TSC differentiation into SpT by regulating theAscl2gene.

scholarly journals Immunocytochemical studies on the localization of plasma and of cellular retinol-binding proteins and of transthyretin (prealbumin) in rat liver and kidney.

1984 ◽  
Vol 98 (5) ◽  
pp. 1696-1704 ◽  
Author(s):  
M Kato ◽  
K Kato ◽  
D S Goodman
Keyword(s):  
Rat Liver ◽  
Binding Protein ◽  
Cell Types ◽  
Retinol Binding Protein ◽  
Specific Staining ◽  
Intense Staining ◽  
Cytoplasmic Staining ◽  
Liver And Kidney ◽  
Diffuse Cytoplasmic Staining ◽  
Parenchymal Cells

The immunocytochemical localization of cellular retinol-binding protein (CRBP), of plasma retinol-binding protein (RBP), and of plasma transthyretin (TTR) was studied in rat liver and kidney. The studies employed normal rats, retinol-deficient rats, and rats fed excess retinol. Antisera were prepared in rabbits against purified rat CRBP, RBP, and TTR. The primary antibodies and goat anti-rabbit IgG were purified by immunosorbent affinity chromatography, using the respective pure antigen coupled to Sepharose as the immunosorbent. This procedure effectively removed cross-reactive and heterophile antibodies, which permitted the specific staining and localization of each antigen by the unlabeled peroxidase-antiperoxidase method. CRBP was found to be localized in two cell types in the liver, the parenchymal cells and the fat-storing cells. Diffuse cytoplasmic staining for CRBP was seen in all the parenchymal cells. Much more intense staining for CRBP was seen in the fat-storing cells. The prominence of the CRBP-positive fat-storing cells changed markedly with vitamin A status. Thus, these cells were most prominent, and appeared most numerous, in liver from rats fed excess retinol. Both RBP and TTR were localized within liver parenchymal cells. The intensity of RBP staining increased markedly in retinol-deficient rat liver, consistent with previous biochemical observations. With the methods employed, specific staining for RBP or TTR was not seen in cells other than the parenchymal cells. In the kidney, all three proteins (CRBP, RBP, and TTR) were localized in the proximal convoluted tubules of the renal cortex. Staining for RBP was much more intense in normal kidney than in kidney from retinol-deficient rats. These findings reflect the fact that RBP in the tubules represents filtered and reabsorbed RBP. The pattern of specific staining for CRBP among the various tubules was very similar to that seen for RBP on adjacent, serial sections of kidney. The function of CRBP in the kidney is not known.

scholarly journals Integrated or Independent Actions of Metformin in Target Tissues Underlying Its Current Use and New Possible Applications in the Endocrine and Metabolic Disorder Area

2021 ◽  
Vol 22 (23) ◽  
pp. 13068
Author(s):  
Giovanni Tulipano
Keyword(s):  
Molecular Mechanisms ◽  
Metabolic Diseases ◽  
Current Knowledge ◽  
Cell Types ◽  
Cellular Level ◽  
Endocrine Tumors ◽  
Age Related ◽  
Distinct Cell ◽  
First Choice ◽  
Integrated Or

Metformin is considered the first-choice drug for type 2 diabetes treatment. Actually, pleiotropic effects of metformin have been recognized, and there is evidence that this drug may have a favorable impact on health beyond its glucose-lowering activity. In summary, despite its long history, metformin is still an attractive research opportunity in the field of endocrine and metabolic diseases, age-related diseases, and cancer. To this end, its mode of action in distinct cell types is still in dispute. The aim of this work was to review the current knowledge and recent findings on the molecular mechanisms underlying the pharmacological effects of metformin in the field of metabolic and endocrine pathologies, including some endocrine tumors. Metformin is believed to act through multiple pathways that can be interconnected or work independently. Moreover, metformin effects on target tissues may be either direct or indirect, which means secondary to the actions on other tissues and consequent alterations at systemic level. Finally, as to the direct actions of metformin at cellular level, the intracellular milieu cooperates to cause differential responses to the drug between distinct cell types, despite the primary molecular targets may be the same within cells. Cellular bioenergetics can be regarded as the primary target of metformin action. Metformin can perturb the cytosolic and mitochondrial NAD/NADH ratio and the ATP/AMP ratio within cells, thus affecting enzymatic activities and metabolic and signaling pathways which depend on redox- and energy balance. In this context, the possible link between pyruvate metabolism and metformin actions is extensively discussed.

Procollagen I-expressing renin cell precursors

2013 ◽  
Vol 305 (3) ◽  
pp. F355-F361 ◽  
Author(s):  
Christian Karger ◽  
Felix Kurtz ◽  
Dominik Steppan ◽  
Ilona Schwarzensteiner ◽  
Katharina Machura ◽  
...  
Keyword(s):  
Salt Intake ◽  
Cell Types ◽  
Cellular Level ◽  
Type I ◽  
Metanephric Mesenchyme ◽  
Perivascular Cell ◽  
Cell Clusters ◽  
Mural Cells ◽  
Type I Procollagen ◽  
Distinct Cell

Renin-expressing cells in the kidney normally appear as mural cells of developing preglomerular vessels and finally impose as granulated juxtaglomerular cells in adult kidneys. The differentiation of renin-expressing cells from the metanephric mesenchyme in general and the potential role of special precursor stages in particular is not well understood. Therefore, it was the aim of this study to search for renin cell precursors in the kidney. As an experimental model, we used kidneys of aldosterone synthase-deficient mice, which display a prominent compensatory overproduction of renin cells that are arranged in multilayered perivascular cell clusters. We found that the perivascular cell clusters contained two apparently distinct cell types, one staining positive for renin and another one staining positive for type I procollagen (PC1). It appeared as if PC1 and renin expression were inversely related at the cellular level. The proportion of renin-positive to PC1-positive cells in the clusters was inversely linked to the rate of salt intake, as was overall renin expression. Our findings suggest that the cells in the perivascular cell clusters can reversibly switch between PC1 and renin expression and that PC1-expressing cells might be precursors of renin cells. A few of those PC1-positive cells were found also in adult wild-type kidneys in the juxtaglomerular lacis cell area, in which renin expression can be induced on demand.

scholarly journals Progenitors oppositely polarize WNT activators and inhibitors to orchestrate tissue development

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Irina Matos ◽  
Amma Asare ◽  
John Levorse ◽  
Tamara Ouspenskaia ◽  
June de la Cruz-Racelis ◽  
...  
Keyword(s):  
Wnt Signaling ◽  
Feedback Loop ◽  
Three Dimensional ◽  
Cell Types ◽  
Cellular Level ◽  
Morphogen Gradient ◽  
Follicle Development ◽  
Distinct Cell ◽  
Hair Follicle Development ◽  
Wnt Inhibitors

To spatially co-exist and differentially specify fates within developing tissues, morphogenetic cues must be correctly positioned and interpreted. Here, we investigate mouse hair follicle development to understand how morphogens operate within closely spaced, fate-diverging progenitors. Coupling transcriptomics with genetics, we show that emerging hair progenitors produce both WNTs and WNT inhibitors. Surprisingly, however, instead of generating a negative feedback loop, the signals oppositely polarize, establishing sharp boundaries and consequently a short-range morphogen gradient that we show is essential for three-dimensional pattern formation. By establishing a morphogen gradient at the cellular level, signals become constrained. The progenitor preserves its WNT signaling identity and maintains WNT signaling with underlying mesenchymal neighbors, while its overlying epithelial cells become WNT-restricted. The outcome guarantees emergence of adjacent distinct cell types to pattern the tissue.

scholarly journals Myoblasts and macrophages share molecular components that contribute to cell–cell fusion

2008 ◽  
Vol 180 (5) ◽  
pp. 1005-1019 ◽  
Author(s):  
Kostandin V. Pajcini ◽  
Jason H. Pomerantz ◽  
Ozan Alkan ◽  
Regis Doyonnas ◽  
Helen M. Blau
Keyword(s):  
Cell Fusion ◽  
Cell Formation ◽  
Cell Types ◽  
Giant Cells ◽  
Nucleotide Exchange ◽  
Multinucleated Cells ◽  
Guanine Nucleotide Exchange ◽  
Distinct Cell ◽  
Molecular Components ◽  
Cell Cell

Cell–cell fusion is critical to the normal development of certain tissues, yet the nature and degree of conservation of the underlying molecular components remains largely unknown. Here we show that the two guanine-nucleotide exchange factors Brag2 and Dock180 have evolutionarily conserved functions in the fusion of mammalian myoblasts. Their effects on muscle cell formation are distinct and are a result of the activation of the GTPases ARF6 and Rac, respectively. Inhibition of ARF6 activity results in a lack of physical association between paxillin and β1-integrin, and disruption of paxillin transport to sites of focal adhesion. We show that fusion machinery is conserved among distinct cell types because Dock180 deficiency prevented fusion of macrophages and the formation of multinucleated giant cells. Our results are the first to demonstrate a role for a single protein in the fusion of two different cell types, and provide novel mechanistic insight into the function of GEFs in the morphological maturation of multinucleated cells.

scholarly journals Morphological Characterization of Basally Located Uninucleate Trophoblast Cells as Precursors of Bovine Binucleate Trophoblast Giant Cells

2018 ◽  
Vol 205 (3) ◽  
pp. 151-163 ◽  
Author(s):  
Jeannette Attiger ◽  
Alois Boos ◽  
Karl Klisch
Keyword(s):  
Electron Microscopy ◽  
Stem Cells ◽  
Cell Types ◽  
Giant Cells ◽  
Morphological Characterization ◽  
Early Stages ◽  
Transmission Electron ◽  
Block Face ◽  
Trophoblast Giant Cells

Binucleate trophoblast giant cells (TGCs) are one characteristic feature of the ruminant placenta. In cows, the frequency of TGCs remains constant for most of the duration of pregnancy. As TGCs are depleted by their fusion with uterine epithelial cells, they need to be constantly formed. It is still unclear whether they develop from stem cells within the trophectoderm or whether they can arise from any uninucleate trophoblast cell (UTC). Within the latter, generally accepted theory, a basally located uninucleate cell (BUC) without contact to the feto-maternal interface would represent a transient cell between a UTC and a TGC. So far, no evidence for the existence of such transient cells or for the presence of stem cells has been shown. The aim of the present study is to morphologically characterize the early stages of TGC development. Placentomal tissue of 6 pregnant cows from different gestational stages (gestational days 51–214) was examined for BUCs, UTCs, and TGCs either in serial sections (light and transmission electron microscopy, TEM, n = 3), in single sections (TEM, n = 2), or by serial block face-scanning electron microscopy (n = 1). These investigations revealed the occurrence of BUCs, as well as young TGCs showing contact with the basement membrane (BM), but without apical contact to the feto-maternal interface. The study morphologically defines these 2 cell types as early stages of TGC development and shows that binucleation of TGCs can precede detachment from the BM.

Mrj encodes a DnaJ-related co-chaperone that is essential for murine placental development

Development ◽  
1999 ◽  
Vol 126 (6) ◽  
pp. 1247-1258 ◽  
Author(s):  
P.J. Hunter ◽  
B.J. Swanson ◽  
M.A. Haendel ◽  
G.E. Lyons ◽  
J.C. Cross
Keyword(s):  
Protein Function ◽  
Cell Types ◽  
Giant Cells ◽  
Gene Trap ◽  
Developmental Defect ◽  
Placental Development ◽  
E Coli ◽  
Mouse Tissues ◽  
Transcription Factor Genes ◽  
Trophoblast Giant Cells

We have identified a novel gene in a gene trap screen that encodes a protein related to the DnaJ co-chaperone in E. coli. The gene, named Mrj (mammalian relative of DnaJ) was expressed throughout development in both the embryo and placenta. Within the placenta, expression was particularly high in trophoblast giant cells but moderate levels were also observed in trophoblast cells of the chorion at embryonic day 8.5, and later in the labyrinth which arises from the attachment of the chorion to the allantois (a process called chorioallantoic fusion). Insertion of the ROSAbetageo gene trap vector into the Mrj gene created a null allele. Homozygous Mrj mutants died at mid-gestation due to a failure of chorioallantoic fusion at embryonic day 8.5, which precluded formation of the mature placenta. At embryonic day 8.5, the chorion in mutants was morphologically normal and expressed the cell adhesion molecule beta4 integrin that is known to be required for chorioallantoic fusion. However, expression of the chorionic trophoblast-specific transcription factor genes Err2 and Gcm1 was significantly reduced. The mutants showed no abnormal phenotypes in other trophoblast cell types or in the embryo proper. This study indicates a previously unsuspected role for chaperone proteins in placental development and represents the first genetic analysis of DnaJ-related protein function in higher eukaryotes. Based on a survey of EST databases representing different mouse tissues and embryonic stages, there are 40 or more DnaJ-related genes in mammals. In addition to Mrj, at least two of these genes are also expressed in the developing mouse placenta. The specificity of the developmental defect in Mrj mutants suggests that each of these genes may have unique tissue and cellular activities.

scholarly journals Polytene chromosomes in mouse trophoblast giant cells

Development ◽  
1988 ◽  
Vol 102 (1) ◽  
pp. 127-134 ◽  
Author(s):  
S. Varmuza ◽  
V. Prideaux ◽  
R. Kothary ◽  
J. Rossant
Keyword(s):  
Dna Replication ◽  
Salivary Glands ◽  
Giant Cell ◽  
Polytene Chromosomes ◽  
Dna Amplification ◽  
Cell Types ◽  
Giant Cells ◽  
Cytological Evidence ◽  
Trophoblast Giant Cells

Mouse trophoblast giant cells undergo successive rounds of DNA replication resulting in amplification of the genome. It has been difficult to determine whether giant cell chromosomes are polyploid as in liver cells or polytene as in Dipteran salivary glands because the chromosomes do not condense. We have examined the pattern of hybridization of mouse giant cells with a variety of in situ chromosome markers to address this question. Hemizygous markers displayed one hybridization signal per nucleus in both diploid and giant cells, while homozygous markers displayed two signals per nucleus in both cell types. These patterns are consistent with cytological evidence indicating that giant cell chromosomes are polytene rather than polyploid. However, in contrast to the situation in Dipteran salivary glands, the two homologues do not appear to be closely associated. We conclude that the mechanism of giant cell DNA amplification involves multiple rounds of DNA replication in the absence of both karyokinesis and cytokinesis, and that sister chromatids, but not homologous chromosomes, remain closely associated during this process.

Fine Structure of the Malpighian Tubules of the Mosquito, Culex pipiens

1971 ◽  
Vol 29 ◽  
pp. 402-403
Author(s):  
Brendan Clifford
Keyword(s):  
Fine Structure ◽  
Culex Pipiens ◽  
Stellate Cell ◽  
Malpighian Tubule ◽  
Cell Types ◽  
Instar Larva ◽  
Malpighian Tubules ◽  
Calliphora Erythrocephala ◽  
Distinct Cell ◽  
Basal Plasma

An ultrastructural investigation of the Malpighian tubules of the fourth instar larva of Culex pipiens was undertaken as part of a continuing study of the fine structure of transport epithelia.Each of the five Malpighian tubules was found to be morphologically identical and regionally undifferentiated. Two distinct cell types, the primary and stellate, were found intermingled along the length of each tubule. The ultrastructure of the stellate cell was previously described in the Malpighian tubule of the blowfly, Calliphora erythrocephala by Berridge and Oschman.The basal plasma membrane of the primary cell is extremely irregular, giving rise to a complex interconnecting network of basal channels. The compartments of cytoplasm entrapped within this system of basal infoldings contain mitochondria, free ribosomes, and small amounts of rough endoplasmic reticulum. The mitochondria are distinctive in that the cristae run parallel to the long axis of the organelle.

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