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Placenta Oct 2010The family of secreted Wingless ligands plays major roles in embryonic development, stem cell maintenance, differentiation and tissue homeostasis. Accumulating evidence... (Review)
Review
The family of secreted Wingless ligands plays major roles in embryonic development, stem cell maintenance, differentiation and tissue homeostasis. Accumulating evidence suggests that the canonical Wnt pathway involving nuclear recruitment of β-catenin and activation of Wnt-dependent transcription factors is also critically involved in development and differentiation of the diverse reproductive tissues. Here, we summarise our present knowledge about expression, regulation and function of Wnt ligands and their frizzled receptors in murine and human endometrial and placental cell types. In mice, Wnt signalling promotes early trophoblast lineage development, blastocyst activation, implantation and chorion-allantois fusion. Moreover, different Wnt ligands play essential roles in the development of the murine uterine tract, in cycling endometrial cells and during decidualisation. In humans, estrogen-dependent endometrial cell proliferation, decidualisation, trophoblast attachment and invasion were shown to be controlled by the particular signalling pathway. Failures in Wnt signalling are associated with infertility, endometriosis, endometrial cancer and gestational diseases such as complete mole placentae and choriocarcinomas. However, our present knowledge is still scarce due to the complexity of the Wnt network involving numerous ligands, receptors and non-canonical pathways. Hence, much remains to be learned about the role of different Wnt signalling cascades in reproductive cell types and their changes under pathological conditions.
Topics: Animals; Cell Differentiation; Decidua; Embryo Implantation; Endometrium; Female; Frizzled Receptors; Humans; Mice; Placenta; Pregnancy; Reproduction; Signal Transduction; Wnt Proteins
PubMed: 20716463
DOI: 10.1016/j.placenta.2010.07.011 -
Journal of Veterinary Internal Medicine 2010Retained fetal membranes (RFM) in cattle have adverse effects on fertility and production. Understanding the pathophysiology and causes of RFM is important for managing... (Review)
Review
Retained fetal membranes (RFM) in cattle have adverse effects on fertility and production. Understanding the pathophysiology and causes of RFM is important for managing this disease. The hormonal processes that lead to normal placental separation are multifactorial and begin before parturition. A variety of risk factors, including early or induced parturition, dystocia, hormonal imbalances, and immunosuppression, can interrupt these normal processes and result in retention of the placenta. Current research does not support the efficacy of many commonly practiced treatments for RFM. Systemic administration of antibiotics can be beneficial for treating metritis after RFM, but antibiotic administration has not been shown to significantly improve future reproduction in cows with RFM. Collagenase injected into the umbilical arteries of retained placentas specifically targets the lack of placentome proteolysis and might enhance placental release. However, such therapy is costly and its benefits in terms of improving subsequent reproductive function have not been evaluated.
Topics: Animals; Cattle; Cattle Diseases; Female; Infertility, Female; Placenta; Placenta, Retained; Pregnancy
PubMed: 20136715
DOI: 10.1111/j.1939-1676.2010.0473.x -
Obstetrics and Gynecology Feb 2014To compare placental lesions for stillbirth cases and live birth controls in a population-based study. (Comparative Study)
Comparative Study
OBJECTIVE
To compare placental lesions for stillbirth cases and live birth controls in a population-based study.
METHODS
Pathologic examinations were performed on placentas from singleton pregnancies using a standard protocol. Data were analyzed overall and within gestational age groups at delivery.
RESULTS
Placentas from 518 stillbirths and 1,200 live births were studied. Single umbilical artery was present in 7.7% of stillbirths and 1.7% of live births, velamentous cord insertion was present in 5% of stillbirths and 1.1% of live births, diffuse terminal villous immaturity was present in 10.3% of stillbirths and 2.3% of live births, inflammation (eg, acute chorioamnionitis of placental membranes) was present in 30.4% of stillbirths and 12% of live births, vascular degenerative changes in chorionic plate were present in 55.7% of stillbirths and 0.5% of live births, retroplacental hematoma was present in 23.8% of stillbirths and 4.2% of live births, intraparenchymal thrombi was present in 19.7% of stillbirths and 13.3% of live births, parenchymal infarction was present in 10.9% of stillbirths and 4.4% of live births, fibrin deposition was present in 9.2% of stillbirths and 1.5% of live births, fetal vascular thrombi was present in 23% of stillbirths and 7% of live births, avascular villi was present in 7.6% of stillbirths and 2.0% of live births, and hydrops was present in 6.4% of stillbirths and 1.0% of live births. Among stillbirths, inflammation and retroplacental hematoma were more common in placentas from early deliveries, whereas thrombotic lesions were more common in later gestation. Inflammatory lesions were especially common in early live births.
CONCLUSIONS
Placental lesions were highly associated with stillbirth compared with live births. All lesions associated with stillbirth were found in live births but often with variations by gestational age at delivery. Knowledge of lesion prevalence within gestational age groups in both stillbirths and live birth controls contributes to an understanding of the association between placental abnormality and stillbirth.
LEVEL OF EVIDENCE
II.
Topics: Adult; Chorioamnionitis; Chorionic Villi; Female; Fetal Death; Gestational Age; Humans; Live Birth; Placenta; Placenta Diseases; Pregnancy; Pregnancy Complications; Single Umbilical Artery; Stillbirth
PubMed: 24402599
DOI: 10.1097/AOG.0000000000000100 -
BioTechniques Dec 2020Syncytin-1 (gene ) has been proposed as a marker of pre-eclampsia and malfunctions in placental development. Placenta is heterogeneous tissue, hence the method of biopsy...
Syncytin-1 (gene ) has been proposed as a marker of pre-eclampsia and malfunctions in placental development. Placenta is heterogeneous tissue, hence the method of biopsy can significantly affect the outcome of analyses. A total of 44 placentae were analyzed by taking 3-30 samples from each. Relative levels of expression in the placental biopsies were characterized by RT-qPCR. Evaluation of ten biopsies from one placenta individually (not pooling them) is recommended due to the high variability of expression. No significant correlation was found between biopsy localization and level of expression; therefore, random sampling is recommended. A long cut from the umbilical cord to the edge of the placenta is a convenient approach to placental sampling.
Topics: Adult; Biopsy; Confidence Intervals; Female; Gene Expression Regulation; Gene Products, env; Humans; Placenta; Pregnancy; Pregnancy Proteins; RNA; Specimen Handling
PubMed: 32967447
DOI: 10.2144/btn-2020-0121 -
The International Journal of... 2010Development of the human placenta is modulated heavily by the intrauterine environment. During the first trimester, development takes place in a low oxygen environment... (Review)
Review
Development of the human placenta is modulated heavily by the intrauterine environment. During the first trimester, development takes place in a low oxygen environment supported by histiotrophic nutrition from the endometrial glands. Consequently, the rate of growth of the chorionic sac is almost invariable across this period, and is remarkably uniform between individuals. Towards the end of the first trimester the intrauterine environment undergoes radical transformation in association with onset of the maternal arterial circulation and the switch to haemotrophic nutrition. The accompanying rise in intraplacental oxygen concentration poses a major challenge to placental tissues, and extensive villous remodelling takes place at this time. Later in pregnancy a wide variety of stressors are capable of affecting placental growth, but in the human, the most common are nutrient deprivation and vascular compromise. The latter is usually secondary to deficient trophoblast invasion and can induce placental oxidative stress. Closely linked to oxidative stress is endoplasmic reticulum stress, and we recently provided the first evidence that the latter plays a major role in the pathophysiology of intrauterine growth restriction. The endoplasmic reticulum is a key regulator of protein synthesis, exerting its effects through the unfolded protein response. Consequently, we observed multiple blocks to translation initiation and elongation in growth restricted placentas. Nutrient deprivation also modulates protein synthesis through the mTOR pathway, and we demonstrated interactions between this pathway and endoplasmic reticulum stress. Protein synthesis inhibition therefore appears to be a common mechanism for regulating placental development under different adverse conditions.
Topics: Female; Humans; Placenta; Placentation; Pregnancy; Protein Biosynthesis; Signal Transduction; Uterus
PubMed: 19757391
DOI: 10.1387/ijdb.082764gb -
Archives of Pathology & Laboratory... Jul 2006It has long been recognized that routine histologic examination of the placenta has limitations, especially with regard to the diagnosis of infectious diseases and the... (Review)
Review
It has long been recognized that routine histologic examination of the placenta has limitations, especially with regard to the diagnosis of infectious diseases and the concomitant cytokine response that may cause severe in utero fetal damage. Immunohistochemical testing of the placenta in such situations can be very useful in terms of identifying the infectious agent as well as in demonstrating a marked increase in cytokines such as tumor necrosis factor alpha and interleukin 8, produced primarily by cells native to the villi and fetal membranes. One hundred placentas (20 normal childbirths, 20 with severe neonatal morbidity of known cause, 25 idiopathic stillbirths where autopsy material was available, 35 with severe idiopathic neonatal morbidity) were examined for a wide variety of infectious diseases and cytokine production. An infectious agent was evident in 19 (76%) of 25 placentas from stillbirths and 28 (80%) of 35 placentas associated with idiopathic severe neonatal morbidity. No infectious agent was noted in the placentas from normal childbirths or cases of known neonatal morbidity. The most common infectious agent was coxsackie virus (51% of infections) followed by bacterial infections (24% of infections). The same infectious agent found in the placenta was found in the corresponding autopsy material from the stillbirths, with the spleen containing the greatest number of infected cells. There was a strong correlation between the number of cells demonstrating cytokine expression (tumor necrosis factor alpha and interleukin 8) and the presence of an infectious disease in the placenta and stillborn. No histologic feature was associated with an in utero infection. Immunohistochemical testing of placentas gives much insight into their structure and function, including, besides infectious disease detection, the marked diversity of function of trophoblasts, the rarity of committed B cell response, and the strong potential of contractility of villi.
Topics: Adult; Biomarkers; Cytokines; Female; Humans; Immunohistochemistry; In Situ Hybridization; Infant, Newborn; Infant, Newborn, Diseases; Placenta; Placenta Diseases; Pregnancy
PubMed: 16831054
DOI: 10.5858/2006-130-979-TUOIAI -
Journal of Nippon Medical School =... Oct 2004In immunofluorescence microscopy (IFM), the repression of out of focus fluorescence signal is crucial in order to obtain high-resolution images. One option to acquire... (Review)
Review
In immunofluorescence microscopy (IFM), the repression of out of focus fluorescence signal is crucial in order to obtain high-resolution images. One option to acquire high vertical resolution (z-axis resolution) is to produce optical sections with a confocal microscope. The z-axis resolution usually obtained with confocal microscopy of biological samples is about 500 nm. Another option is to produce very thin sections with a cryo-ultramicrotome (physical sections). The ultrathin cryosections we employ are about 100 nm in thickness: thus all of the fluorescence must come from within this 100 nm thickness. The use of ultrathin cryosections permits the acquisition of extremely high-quality images and minimizes the possibility for false localization in IFM (Fig. 1). Ultrathin cryosections can be applied to immunoelectron microscopy (IEM) as well as IFM (Fig. 2). We show new methods of ultrathin cryosection immunocytochemistry(1-3). Human full-term placentas were fixed with 4% paraformaldehyde, solidified with 10% gelatin, infiltrated with 2.3 M sucrose, and then frozen in liquid nitrogen. Ultrathin cryosections were cut with a cryo-ultramicrotome and then transferred to glass cover slips for IFM or to nickel grids for IEM. Cryosections were incubated with mouse anti-p230, a trans-Golgi network marker, and subsequently incubated with Alexa 488-labeled goat anti-mouse IgG or with goat anti-mouse 5-nm colloidal gold particles. For visualization and preservation of ultrastructure of cryosections at the electron microscopic level, the sections on grids were postfixed with ferrocyanide-reduced osmium and then stained with uranyl acetate and lead citrate in polyvinyl alcohol(1). Ultrathin cryosection immunocytochemistry should be an important technique for functional genomics research, especially for the analysis of the in situ expression of target molecules(2,3).
Topics: Cryoultramicrotomy; Female; Humans; Immunohistochemistry; Microscopy, Fluorescence; Microscopy, Immunoelectron; Placenta; Pregnancy
PubMed: 15514446
DOI: 10.1272/jnms.71.306 -
International Journal of Environmental... May 2019The aim of the study was to investigate relationships between the concentrations of macroelements (Ca), microelements (Cr, Cu, Fe, Mn, Mo, Ni, Sn, Sr, V, Zn) and heavy...
The aim of the study was to investigate relationships between the concentrations of macroelements (Ca), microelements (Cr, Cu, Fe, Mn, Mo, Ni, Sn, Sr, V, Zn) and heavy metals (Ag, Cd, Pb) in the placenta, fetal membrane and umbilical cord. Furthermore, we examined relationships between the concentrations of these metals in the studied afterbirths and maternal age, gestational age, placenta parameters (breadth, length, weight) and newborn parameters (length, weight and Apgar score). This study confirms previously reported Zn-Cd, Pb-Cd and Ni-Pb interactions in the placenta. New types of interactions in the placenta, fetal membrane and umbilical cord were also noted. Analysis of the correlations between metal elements in the afterbirths (placenta, fetal membrane and umbilical cord) and biological parameters showed the following relationships: maternal age and Mn (in the fetal membrane); gestational age and Cr, Fe, Zn (in the fetal membrane), Ag and Cu (in the umbilical cord); newborn's length and Sr (in the placenta), Ag (in the umbilical cord); newborn's weight and Sr (in the placenta), Cu (in the fetal membrane), Ag (in the umbilical cord); Apgar score and Ca, Cr and Ni (in the umbilical cord); placenta's length and Cr and Sn (in the fetal membrane), Cu (in the umbilical cord); placenta's width and Mo, Pb (in the placenta) and placenta weight and Sr (in the placenta), Ag, Fe, Mn (in the fetal membrane). The results show the influence of metals on the placenta, mother and newborn parameters, and the same point indicates the essential trace elements during the course of pregnancy.
Topics: Extraembryonic Membranes; Female; Gestational Age; Humans; Infant, Newborn; Maternal Age; Metals, Heavy; Placenta; Pregnancy; Umbilical Cord
PubMed: 31071998
DOI: 10.3390/ijerph16091615 -
Genes Apr 2023Fatty acids (FAs) are essential substances for the growth and development of the fetus and placenta. The growing fetus and placenta must obtain adequate FAs received...
Fatty acids (FAs) are essential substances for the growth and development of the fetus and placenta. The growing fetus and placenta must obtain adequate FAs received from the maternal circulation and facilitated by various placental FA carriers, including FA transport proteins (FATPs), FA translocase (FAT/CD36), and cytoplasmic FA binding proteins (FABPs). Placental nutrition transport was regulated by imprinted genes and insulin-like growth factor 2 (). Nevertheless, the relationship between the expression patterns of H19/IGF2 and placental fatty acid metabolism throughout pig pregnancy remains poorly studied and unclear. We investigated the placental fatty acid profile, expression patterns of FA carriers, and H19/IGF2 in the placentae on Days 40 (D40), 65 (D65), and 95 (D95) of pregnancy. The results showed that the width of the placental folds and the number of trophoblast cells of D65 placentae were significantly increased than those of D40 placentae. Several important long-chain FAs (LCFAs), including oleic acid, linoleic acid, arachidonatic acid, eicosapentaenoic acid, and docosatetraenoic acid, in the pig placenta showed dramatically increased levels throughout pregnancy. The pig placenta possessed higher expression levels of CD36, FATP4, and FABP5 compared with other FA carriers, and their expression levels had significantly upregulated 2.8-, 5.6-, and 12.0-fold from D40 to D95, respectively. The transcription level of was dramatically upregulated and there were corresponding lower DNA methylation levels in the DMR2 in D95 placentae relative to D65 placentae. Moreover, in vitro experimentation revealed that the overexpression of IGF2 resulted in a significant increase in fatty acid uptake and expression levels of , and in PTr2 cells. In conclusion, our results indicate that CD36, FATP4, and FABP5 may be important regulators that enhance the transport of LCFAs in the pig placenta and that IGF2 may be involved in FA metabolism by affecting the FA carriers expression to support the growth of the fetus and placenta during late pregnancy in pigs.
Topics: Pregnancy; Female; Animals; Swine; Placenta; Fatty Acids; DNA Methylation; Fetus; Trophoblasts; Carrier Proteins
PubMed: 37107630
DOI: 10.3390/genes14040872 -
BMC Pregnancy and Childbirth Jun 2020There has been debate about the existence of lymphatic vessels in placenta. Lymphatic endothelial cell (LEC) markers such as LYVE-1 and podoplanin/D2-40 have been found,...
BACKGROUND
There has been debate about the existence of lymphatic vessels in placenta. Lymphatic endothelial cell (LEC) markers such as LYVE-1 and podoplanin/D2-40 have been found, although PROX1 has not been detected. The most reliable marker for LECs is the double staining for CD31 and PROX1, which has not been performed yet.
METHODS
We studied three term placentas and dissected them into three areas: i.) basal plate area, ii.) intermediate area, and iii.) chorionic plate area. We used immunofluorescence single and double staining with antibodies against CD31, PROX1, LYVE-1, VEGFR-3, D2-40/PDPN, CD34, CCBE-1, and vimentin, as well as nested PCR, qPCR, Western blot and transmission electron microscopy (TEM).
RESULTS
At TEM level we observed structures that have previously mistakenly been interpreted as lymphatics, however, we did not find any CD31/PROX1 double-positive cells in placenta. Absence of PROX1 was also noted by nested PCR, qPCR and Western blot. Also, LEC marker VEGFR-3 was expressed only in a small number of scattered leukocytes but was absent from vessels. The LEC marker D2-40/PDPN was expressed in most stromal cells, and the LEC marker LYVE-1 was found in a considerable number of stromal cells, but not in endothelial cells, which were positive for CD31, CD34, CCBE-1 and vimentin. Additionally, vimentin was found in stromal cells.
CONCLUSIONS
Our studies clearly show absence of lymphatics in term placenta. We also show that the functional area of the mother's endometrium is not penetrated by lymphatics in term pregnancy.
Topics: Biomarkers; Endometrium; Endothelial Cells; Female; Humans; Lymphatic Vessels; Membrane Glycoproteins; Placenta; Pregnancy; Transcription Factors; Vascular Endothelial Growth Factor Receptor-3
PubMed: 32600346
DOI: 10.1186/s12884-020-03073-w