scholarly journals Development and function of trophoblast giant cells in the rodent placenta

2010 ◽  
Vol 54 (2-3) ◽  
pp. 341-354 ◽  
Author(s):  
Dong Hu ◽  
James C. Cross
2012 ◽  
Vol 7 (3) ◽  
pp. 313-318
Author(s):  
Masahisa Watarai ◽  

The mechanisms of abortion induced by bacterial infection are largely unknown. We found that Brucella abortus, a causative agent of brucellosis and a facultative intracellular pathogen, caused abortion in pregnant mice. High rates of abortion are observed for bacterial infection on day 4.5 of gestation, but not for other days. Regardless of whether fetuses are aborted or not, the transmission of bacteria to the fetus and bacterial replication in the placenta are observed. There is a higher degree of bacterial colonization in the placenta than in other organs and many bacteria are detected in trophoblast giant cells in the placenta. The intracellular growth-defective virB4 mutant and attenuated vaccine strain S19 do not induce abortion. In the case of abortion, the induction of IFN-γ and RANTES production is observed at day 7.5 of gestation – the placental development period – for infection by the wild type strain but not by the virB4 mutant or S19. B. abortus-infected pregnant IFN-γ knockoutmice die within 15 days of infection, but nonpregnant IFN-γ knockout mice remain alive. The neutralization of IFN-γ or RANTES, in which production is induced by infection with B. abortus serves to prevent abortion. These results indicate that abortion induced by B. abortus infection is regulated by IFN-γ during the period of placental development, and the production and function of RANTES are correlated with IFN-γ.


2004 ◽  
Vol 16 (9) ◽  
pp. 16
Author(s):  
S. L. Dunwoodie ◽  
S. L. Withington ◽  
D. B. Sparrow ◽  
A. N. Scott ◽  
J. I. Preis ◽  
...  

Cited1 and Cited2 interact with CBP and p300. CBP/p300 bind numerous proteins and evidence exists, for Cited2 at least, that Cited binding prevents the binding of other proteins to CBP/p300. Since CBP/p300 interact with many proteins, can acetylate protein and DNA, and act as a ubiquitin ligase, it is likely that Cited1 and Cited2 function at a number of sites during development. We have generated mice that carry a null mutant allele for each of these genes. Analysis of null mutant embryos demonstrates that both Cited1 and Cited2 are required for normal embryonic development and survival. Although both Cited1 and Cited2 are expressed in the developing embryo and placenta, it appears that abnormal placental development and function is the cause of embryonic death. The defect that develops in the placentas of Cited1 null mutants is not apparent until late in gestation (16.5dpc). Cited1 null mutants are smaller than controls at birth and die during the early postnatal period. The placentas of these mutants are disorganised, with spongiotrophoblasts projecting in to the labyrinthine layer. In addition, resin casts of the maternal blood spaces within these placentas revealed extremely enlarged blood sinuses. We are searching for factors that could result in the increased size of the maternal blood sinuses. Cited2 null placentas and embryos are significantly smaller than controls; mutants die 3/4 the way through gestation (15.5dpc). The null mutant placentas have proportionally fewer spongiotrophoblasts, trophoblast giant cells and invasive trophoblasts. In addition, resin casts of fetal vasculature of the placenta reveal that the capillary network is underdeveloped. Through the isolation of trophoblast stem (TS) cells we are exploring the possibility that TS cell proliferation and/or differentiation is impaired due to a lack of Cited2. We suspect that the development of the phenotype may relate to the Hypoxia Inducible Factor-1a (HIF1a) transcription factor as Cited2 expression is induced by HIF1 and it acts to negatively regulate its activity.


Development ◽  
1981 ◽  
Vol 61 (1) ◽  
pp. 277-287
Author(s):  
A. J. Copp

The number of trophoblast giant cells in outgrowths of mouse blastocysts was determined before, during and after egg-cylinder formation in vitro. Giant-cell numbers rose initially but reached a plateau 12 h before the egg cylinder appeared. A secondary increase began 24 h after egg-cylinder formation. Blastocysts whose mural trophectoderm cells were removed before or shortly after attachment in vitro formed egg cylinders at the same time as intact blastocysts but their trophoblast outgrowths contained fewer giant cells at this time. The results support the idea that egg-cylinder formation in vitro is accompanied by a redirection of the polar to mural trophectoderm cell movement which characterizes blastocysts before implantation. The resumption of giant-cell number increase in trophoblast outgrowths after egg-cylinder formation may correspond to secondary giant-cell formation in vivo. It is suggested that a time-dependent change in the strength of trophoblast cell adhesion to the substratum occurs after blastocyst attachment in vitro which restricts the further entry of polar cells into the outgrowth and therefore results in egg-cylinder formation.


Placenta ◽  
2013 ◽  
Vol 34 (9) ◽  
pp. A8
Author(s):  
Roberta Hannibal ◽  
Edward Chuong ◽  
Juan Carlos Rivera Mulia ◽  
David Gilbert ◽  
Anton Valouev ◽  
...  

2013 ◽  
Vol 63 (8) ◽  
pp. 408-414 ◽  
Author(s):  
Tadashige Nozaki ◽  
Hiroaki Fujimori ◽  
Junhui Wang ◽  
Hiroshi Suzuki ◽  
Hiroshi Imai ◽  
...  

2019 ◽  
Vol 6 (6) ◽  
pp. 190360 ◽  
Author(s):  
Liuliu Yan ◽  
Lulu Lu ◽  
Fangbin Hu ◽  
Dattatrya Shetti ◽  
Kun Wei

Osteoclasts are multinuclear giant cells that have unique ability to degrade bone. The search for new medicines that modulate the formation and function of osteoclasts is a potential approach for treating osteoclast-related bone diseases. Piceatannol (PIC) is a natural organic polyphenolic stilbene compound found in diverse plants with a strong antioxidant and anti-inflammatory effect. However, the effect of PIC on bone health has not been scrutinized systematically. In this study, we used RAW264.7, an osteoclast lineage of cells of murine macrophages, to investigate the effects and the underlying mechanisms of PIC on osteoclasts. Here, we demonstrated that PIC treatment ranging from 0 to 40 µM strongly inhibited osteoclast formation and bone resorption in a dose-dependent manner. Furthermore, the inhibitory effect of PIC was accompanied by the decrease of osteoclast-specific genes. At the molecular level, PIC suppressed the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK1/2), NF-κB p65, IκBα and AKT. Besides, PIC promoted the apoptosis of mature osteoclasts by inducing caspase-3 expression. In conclusion, our results suggested that PIC inhibited RANKL-induced osteoclastogenesis and bone resorption by suppressing MAPK, NF-κB and AKT signalling pathways and promoted caspase3-mediated apoptosis of mature osteoclasts, which might contribute to the treatment of bone diseases characterized by excessive bone resorption.


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