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1.
Article in Chinese | WPRIM | ID: wpr-879535

ABSTRACT

OBJECTIVE@#To compare the mRNA level of cell proliferation-related genes Twist1, SIRT1, FGF2 and TGF-β3 in placenta mesenchymal stem cells (PA-MSCs), umbilical cord mensenchymals (UC-MSCs) and dental pulp mesenchymal stem cells (DP-MSCs).@*METHODS@#The morphology of various passages of PA-MSCs, UC-MSCs and DP-MSCs were observed by microscopy. Proliferation and promoting ability of the three cell lines were detected with the MTT method. Real-time PCR (RT-PCR) was used to determine the mRNA levels of Twist1, SIRT1, FGF2, TGF-β3.@*RESULTS@#The morphology of UC-MSCs and DP-MSCs was different from that of PA-MSCs. Proliferation ability and promoting ability of the PA-MSCs was superior to that of UC-MSCs and DP-MSCs. In PA-MSCs, expression level of Twist1 and TGF-β3 was the highest and FGF2 was the lowest. SIRT1 was highly expressed in UC-MSCs. With the cell subcultured, different expression levels of Twist1, SIRT1, FGF2, TGF-β3 was observed in PA-MSCs, UC-MSCs and DP-MSCs.@*CONCLUSION@#Up-regulated expression of the Twist1, SIRT1 and TGF-β3 genes can promote proliferation of PA-MSCs, UC-MSCs and DP-MSCs, whilst TGF-β3 may inhibit these. The regulatory effect of Twist1, SIRT1, FGF2 and TGF-β3 genes on PA-MSCs, UC-MSCs and DP-MSCs are different.


Subject(s)
Cell Differentiation , Cell Proliferation/genetics , Cells, Cultured , Dental Pulp/cytology , Female , Fibroblast Growth Factor 2/genetics , Humans , Mesenchymal Stem Cells/cytology , Nuclear Proteins/genetics , Placenta/cytology , Pregnancy , Sirtuin 1/genetics , Transforming Growth Factor beta3/genetics , Twist-Related Protein 1/genetics , Umbilical Cord/cytology
2.
Pesqui. vet. bras ; 38(6): 1232-1238, jun. 2018. tab
Article in English | ID: biblio-955450

ABSTRACT

Newborn's health is directly related to gestational conditions and placental efficiency. The aims of this study were: (1) To evaluate hematological and biochemical parameters of foals born from mares with placentitis at birth and at 24h of age, (2) to verify if placental pathology had any influence on neonatal maturity degree through hematological and biochemical response of those foals. According to placental findings (control and placentitis) and neonatal maturity degree (mature and immature), foals were divided into three groups: (1) Control group (n=22), foals born from mares with placentitis and classified as (2) Mature (n=26), and (3) Immature (n=10). The hematocrit and plasma concentration of fibrinogen, total plasma protein, white blood cells count, lactate, glucose, creatinine, urea, albumin, bilirubin, triglyceride, cholesterol, calcium, phosphorus, magnesium, aspartate aminotransferase (AST), creatine kinase (CK), alkaline phosphatase (ALP), and gamma-glutamyltransferase (GGT) were measured. Placental features were significantly different between neonatal maturity degree (P=0.001). Mares that had acute placentitis foaled more immature neonates (n=8/10; 80%). Concentrations of fibrinogen (P=0.003), creatinine (P=0.021), total cholesterol (P=0.014), AST (P=0.001), GGT (P=0.002), total (P=0.001) and unconjugated bilirubin (P=0.010) were higher at birth in the Immature group, whereas albumin levels were lower (P=0.002). Foals born from mares with placentitis presented hyperlactatemia at 24h of age (P=0.002). Acute placentitis had an influence on the neonatal maturity, allowing an accelerated but incomplete fetal maturation. The monitoring of lactate, fibrinogen, creatinine, bilirubin, cholesterol, albumin, AST, and GGT levels, associated with clinical, physical, and behavior evaluation may contribute as indicators of neonatal maturity.(AU)


A saúde do neonato está diretamente relacionada às condições gestacionais e eficiência placentária. Os objetivos deste estudo foram: (1) avaliar parâmetros hematológicos e bioquímicos de potros nascidos de éguas com placentite ao nascimento e com 24h de vida e (2) verificar se a patologia placentária exerceu influência no grau de maturidade através da resposta hemato-bioquímica destes neonatos. De acordo com os resultados histopatológicos placentários (controle e placentite) e grau de maturidade neonatal (maturo e imaturo), os potros foram divididos em três grupos: grupo controle (n=22); e potros nascidos de éguas com placentite classificados como (2) maturos (n=26) e (3) imaturos (n=10). Foi avaliado hematócrito e concentrações sanguíneas de fibrinogênio, proteína plasmática total, leucócitos totais, lactato, glicose, creatinina, uréia, albumina, bilirrubinas, triglicerídeos, colesterol, cálcio, fósforo, magnésio, aspartato aminotransferase (AST), creatina quinase (CK), fosfatase alcalina (FA) e gama glutamiltranferase (GGT). As características placentárias foram significativamente diferentes entre os graus de maturidade neonatal (P=0.001). Éguas com placentite aguda produziram mais potros imaturos (n=8/10; 80%). No nascimento, os potros imaturos apresentaram maiores concentrações de fibrinogênio (P=0,003), creatinina (P=0,021), colesterol total (P=0,0014), AST (P=0,001), GGT (P=0,002), bilirrubina indireta (P=0,010) e total (P=0,001) e menor concentração de albumina (P=0,002). Os potros nascidos de éguas com placentite apresentaram hiperlactatemia com 24h de vida (P=0,002). A placentite aguda exerceu influência na maturidade neonatal, permitindo uma maturação fetal acelerada, porém, incompleta. Mensurações dos níveis sanguíneos de lactato, fibrinogênio, creatinina, colesterol total, AST, GGT, bilirrubinas e albumina, associado à avaliação clínica, física e comportamental, podem contribuir como indicadores de maturidade neonatal.(AU)


Subject(s)
Animals , Female , Pregnancy , Placenta/cytology , Placenta/chemistry , Horses/blood , Biochemistry/classification
3.
Braz. j. med. biol. res ; 51(1): e6382, 2018. tab, graf
Article in English | LILACS | ID: biblio-889010

ABSTRACT

Biological biomaterials for tissue engineering purposes can be produced through tissue and/or organ decellularization. The remaining extracellular matrix (ECM) must be acellular and preserve its proteins and physical features. Placentas are organs of great interest because they are discarded after birth and present large amounts of ECM. Protocols for decellularization are tissue-specific and have not been established for canine placentas yet. This study aimed at analyzing a favorable method for decellularization of maternal and fetal portions of canine placentas. Canine placentas were subjected to ten preliminary tests to analyze the efficacy of parameters such as the type of detergents, freezing temperatures and perfusion. Two protocols were chosen for further analyses using histology, scanning electron microscopy, immunofluorescence and DNA quantification. Sodium dodecyl sulfate (SDS) was the most effective detergent for cell removal. Freezing placentas before decellularization required longer periods of incubation in different detergents. Both perfusion and immersion methods were capable of removing cells. Placentas decellularized using Protocol I (1% SDS, 5 mM EDTA, 50 mM TRIS, and 0.5% antibiotic) preserved the ECM structure better, but Protocol I was less efficient to remove cells and DNA content from the ECM than Protocol II (1% SDS, 5 mM EDTA, 0.05% trypsin, and 0.5% antibiotic).


Subject(s)
Animals , Female , Pregnancy , Dogs , Placenta/cytology , Tissue Engineering/methods , Extracellular Matrix , Fetus/cytology , Sodium Dodecyl Sulfate/pharmacology , Biocompatible Materials , Microscopy, Electron, Scanning , Reproducibility of Results , Fluorescent Antibody Technique , Collagen/analysis , Fibronectins/analysis , Laminin/analysis , Edetic Acid , Cold Temperature , Tissue Engineering/veterinary , Immersion
5.
Rev. bras. ginecol. obstet ; 35(9): 407-412, set. 2013. ilus, tab
Article in English | LILACS | ID: lil-690692

ABSTRACT

PURPOSE: In placentas from uncomplicated pregnancies, Hofbauer cells either disappear or become scanty after the fourth to fifth month of gestation. Immunohistochemistry though, reveals that a high percentage of stromal cells belong to Hofbauer cells. The aim of this study was to investigate the changes in morphology and density of Hofbauer cells in placentas from normal and pathological pregnancies. METHODS: Seventy placentas were examined: 16 specimens from normal term pregnancies, 10 from first trimester's miscarriages, 26 from cases diagnosed with chromosomal abnormality of the fetus, and placental tissue specimens complicated with intrauterine growth restriction (eight) or gestational diabetes mellitus (10). A histological study of hematoxylin-eosin (HE) sections was performed and immunohistochemical study was performed using the markers: CD 68, Lysozyme, A1 Antichymotrypsine, CK-7, vimentin, and Ki-67. RESULTS: In normal term pregnancies, HE study revealed Hofbauer cells in 37.5% of cases while immunohistochemistry revealed in 87.5% of cases. In first trimester's miscarriages and in cases with prenatal diagnosis of fetal chromosomal abnormalities, both basic and immunohistochemical study were positive for Hofbauer cells. In pregnancies complicated with intrauterine growth restriction or gestational diabetes mellitus, a positive immunoreaction was observed in 100 and 70% of cases, respectively. CONCLUSIONS: Hofbauer cells are present in placental villi during pregnancy, but with progressively reducing density. The most specific marker for their detection seems to be A1 Antichymotrypsine. It is remarkable that no mitotic activity of Hofbauer cells was noticed in our study, as the marker of cellular multiplication Ki-67 was negative in all examined specimens.


OBJETIVO: Em placentas de gestações sem complicações, as células de Hofbauer desaparecem ou se tornam raras após o quarto ou quinto mês de gestação. Entretanto, a imunohistoquímica revela que uma alta porcentagem de células estromais pertencem às células de Hofbauer. O objetivo do presente estudo foi investigar as alterações da morfologia e densidade das células de Hofbauer em placentas de gestações normais e patológicas. MÉTODOS: Foram examinadas 70 placentas: 16 provenientes de gestações normais a termo, 10 de abortos espontâneos no primeiro trimestre, 26 de casos diagnosticados como anormalidade cromossômica do feto, e amostras de tecido placentário com complicações causadas pela restrição de crescimento intrauterino (8) ou pelo diabetes mellitus gestacional (10). Cortes corados com hematoxilina-eosina (HE) foram submetidos a estudo histológico e imunohistoquímico utilizando-se os seguintes marcadores: CD 68, lisozima, antiquimotripsina A1, CK-7, vimentina, e Ki-67. RESULTADOS: Em gestações normais a termo, o estudo HE revelou células de Hofbauer em 37,5% dos casos, enquanto a imunohistoquímica as revelou em 87,5% dos casos. Em abortos do primeiro trimestre e em casos de diagnóstico prenatal de anormalidades cromossômicas fetais, tanto o estudo básico como o estudo imunohistoquímico foram positivos para células de Hofbauer. Em gestações complicadas pela restrição de crescimento intrauterino ou pelo diabetes mellitus gestacional, imunoreação positiva foi observada respectivamente em 100 e 70% dos casos. CONCLUSÕES: As células de Hofbauer estão presentes nos vilos placentários durante a gestação, embora com densidade progressivamente reduzida. O marcador mais específico para sua detecção parece ser a antiquimotripsina A1. Vale salientar que atividade mitótica de células de Hofbauer não foi detectada em nosso estudo, uma vez que o marcador de multiplicação celular Ki-67 foi negativo em todas as amostras examinadas.


Subject(s)
Female , Humans , Pregnancy , Placenta/cytology , Pregnancy Complications/pathology , Chorionic Villi/pathology , Placenta/pathology
7.
Article in English | WPRIM | ID: wpr-159031

ABSTRACT

This study focused on the characterization of mesenchymal stromal cells (MSCs) from the chorion of human full term placenta from 15 donors. Chorionic MSCs revealed homologous fibroblast-like morphology and expressed CD73, CD29, CD105, and CD90. The hematopoietic stem cell markers including HLA DR, CD11b, CD34, CD79a, and CD45 were not expressed. The growth kinetics of their serial passage was steady at the later passages (passage 10). The multilineage capability of chorionic MSCs was demonstrated by successful adipogenic, osteogenic and chondrogenic differentiation and associated gene expression. Chorionic MSCs expressed genes associated with undifferentiated cells (NANOG, OCT4, REX1) and cardiogenic or neurogenic markers such as SOX2, FGF4, NES, MAP2, and NF. TERT was negative in all the samples. These findings suggest that chorionic MSCs undifferentiated stem cells and less likely to be transformed into cancer cells. A low HLA DR expression suggests that chorionic MSCs may serve as a great source of stem cells for transplantation because of their immune-privileged status and their immunosuppressive effect. Based on these unique properties, it is concluded that chorionic MSCs are pluripotent stem cells that are probably less differentiated than BM-MSCs, and they have considerable potential for use in cell-based therapies.


Subject(s)
Antigens, CD/genetics , Cell Differentiation , Cell Proliferation , Cells, Cultured , Chorion/cytology , Female , Gene Expression Regulation , HLA-DR Antigens/genetics , Humans , Mesenchymal Stem Cells/cytology , Placenta/cytology , Pregnancy , Transcription Factors/genetics
8.
Rev. chil. obstet. ginecol ; 76(6): 431-438, 2011. ilus
Article in Spanish | LILACS | ID: lil-612144

ABSTRACT

Antecedentes: La placenta como otros órganos, normalmente presenta apoptosis, proceso fundamental para el mantenimiento y renovación de las estructuras. Para que este complejo proceso se realice con éxito, es necesario la estricta sincronización y modulación de las diferentes etapas de la apoptosis. Cuando la regulación falla, síndromes patológicos como la preeclampsia pueden iniciarse. Objetivo: Revisar los mecanismos moleculares implicados en la apoptosis de la placenta y sus anomalías. Método: Se realizaron búsquedas de los artículos sobre apoptosis placentaria y preeclampsia, en bases de datos Medline y otras fuentes científicas. Resultados: Muchos de los artículos confirman que la apoptosis placentaria anormal en diferentes períodos de la gestación está involucrada en la patogénesis de la preeclampsia. Conclusiones: Las anomalías de la apoptosis placentaria están relacionadas con el desarrollo posterior de preeclampsia.


Background: Placenta like other organs, normally presents apoptosis as a fundamental process for the maintenance and renovation of structures. For this complex process to occur successfully, strict synchronization and modulation of the different stages of apoptosis are needed. When regulation of these mechanisms fails, pathologic syndromes as preeclampsia can take course. Objective: To review the molecular mechanisms involved in placental apoptosis and its anomalies. Methods: Articles about placental apoptosis and preeclampsia were searched in Medline Database and other scientific sources. Results: Many articles report and confirm that abnormal placental apoptosis at different gestational periods is involved in the pathogenesis of preeclampsia. Conclusions: Anomalies in placental apoptosis are related to the posterior development of preeclampsia.


Subject(s)
Humans , Female , Pregnancy , Apoptosis/physiology , Placenta/cytology , Placenta/physiopathology , Pre-Eclampsia/physiopathology , Trophoblasts/physiology
9.
Int. j. morphol ; 28(3): 829-834, Sept. 2010. ilus
Article in English | LILACS | ID: lil-577192

ABSTRACT

Apoptosis is a permanent and dynamic physiological process by which an organism eliminates the undesirable cells without causing an inflammatory response. The objective of this work was to study the expression of FAS, DR4 and other members of the TNF-R1 superfamily extrinsic route apoptotic receptors the DNA fragmentation and the cellular apoptosis in placental samples at the early, mid and late pregnancy on +/- 30, +/- 55 and +/- 114 gestational days, respectively. We used placental histological sections of samples fixed in buffered saline formaldehyde. Immunohistochemical techniques were performed to detect the apoptotic receptors, whereas the DNA fragmentation was detected by TUNEL reaction and apoptotic cellular ultrastructure was detected by TEM conventional techniques. Apoptosis related receptors were immunolocalized in the early pig gestation and correlated with apoptosis, suggesting a role in the cellular remodelling of the placenta. At gestation day 55, apoptosis might be correlated to FAS route, but not by DR4-mediating pathway. At the end of gestation, increased apoptosis and both receptors markers were detected showing cellular death due to the extrinsic route through FAS and DR4 receptors. In conclusion, the immunolocalization of FAS and TNF R-1 receptors along the pig placental development correlates with TUNEL reaction and with apoptotic ultrastructure observed by TEM and seems to occur through different pathways along gestation.


La apoptosis es un proceso fisiológico, dinámico y permanente a través del cual un organismo elimina células indeseables sin provocar una respuesta inflamatoria. El objetivo del presente trabajo fue estudiar la expresión de los receptores de la vía extrínseca de apoptosis, FAS, DR4 y otros miembros de la superfamilia TNF-R1, la fragmentación del ADN y la apoptosis celular a través de TEM, en muestras placentarias del inicio, la mitad y el final de la gestación, hacia el día +/- 30, +/- 55 y +/- 114 de preñez, respectivamente. Se realizaron cortes histológicos de las muestras placentarias fijadas en formol tamponado. Para la detección de los receptores de apoptosis se realizaron técnicas inmunohistoquímicas, para el estudio de la fragmentación del ADN se utilizó el ensayo TUNEL y para el análisis de la ultraestructura celular apoptótica la técnica convencional de TEM. La inmunolocalización de los receptores de muerte celular al inicio de la preñez porcina sugiere el rol de la apoptosis en la remodelación celular placentaria. Hacia el día 55 de preñez, la apoptosis detectada ocurriría únicamente a través de la vía del receptor FAS, no del receptor DR4. Al final de la gestación, se detectó un incremento de la apoptosis y la expresión de ambos receptores, indicando que la muerte celular a través de la vía de señalización extrínseca estaría inducida por los receptores FAS y DR4. En conclusión, la inmunolocalización de los receptores FAS y otros miembros del TNF-R1, los resultados de TUNEL y la ultraestructura celular apoptótica observada en la placentación porcina, indican que la apoptosis detectada ocurre por diferentes vías de inducción a lo largo de la gestación.


Subject(s)
Animals , Female , Pregnancy , /physiology , /physiology , Apoptosis/physiology , Placenta/cytology , Swine/anatomy & histology , Receptors, Tumor Necrosis Factor, Type I/physiology , DNA Fragmentation , Fas Ligand Protein , Immunohistochemistry , In Situ Nick-End Labeling , Photomicrography , Placentation , Placenta/ultrastructure , Swine/physiology , Receptors, Death Domain
10.
Article in English | WPRIM | ID: wpr-112652

ABSTRACT

This study was done to evaluate the stemness of human mesenchymal stem cells (hMSCs) derived from placenta according to the development stage and to compare the results to those from adult bone marrow (BM). Based on the source of hMSCs, three groups were defined: group I included term placentas, group II included first-trimester placentas, and group III included adult BM samples. The stemness was evaluated by the proliferation capacity, immunophenotypic expression, mesoderm differentiation, expression of pluripotency markers including telomerase activity. The cumulative population doubling, indicating the proliferation capacity, was significantly higher in group II (P<0.001, 31.7+/-5.8 vs. 15.7+/-6.2 with group I, 9.2+/-4.9 with group III). The pattern of immunophenotypic expression and mesoderm differentiation into adipocytes and osteocytes were similar in all three groups. The expression of pluripotency markers including ALP, SSEA-4, TRA-1-60, TRA-1-81, Oct-4, and telomerase were strongly positive in group II, but very faint positive in the other groups. In conclusions, hMSCs from placentas have different characteristics according to their developmental stage and express mesenchymal stemness potentials similar to those from adult human BMs.


Subject(s)
Antigens, Surface/metabolism , Bone Marrow Cells/cytology , Cell Proliferation , Female , Humans , Immunophenotyping , Mesenchymal Stem Cells/cytology , Mesoderm/cytology , Octamer Transcription Factor-3/metabolism , Placenta/cytology , Pregnancy , Pregnancy Trimester, First , Proteoglycans/metabolism , Stage-Specific Embryonic Antigens/metabolism , Telomerase/metabolism
11.
Rev. bras. ginecol. obstet ; 31(2): 90-93, fev. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-512039

ABSTRACT

OBJETIVO: verificar a quantidade de células CD68+ no estroma das vilosidades coriônicas na placenta de gestações submetidas ou não ao trabalho de parto. MÉTODOS: estudo transversal, com gestantes saudáveis a termo, das quais 31 placentas foram examinadas pela técnica de imunoistoquímica. Vinte placentas foram obtidas após partos vaginais (GVAG) e 11 obtidas em cesarianas eletivas (GCES). Lâminas foram preparadas com amostras de vilosidades coriônicas e submetidas à marcação com anticorpo anti-CD68, específico para macrófagos. Foram contadas as células marcadas e as não marcadas dentro das vilosidades. Testes estatísticos não-paramétricos foram utilizados para a análise. RESULTADOS: entre 6.424 células contadas no estroma das vilosidades das 31 placentas, 1.135 células (17,6%) foram marcadas pelo CD68+. Em cada amostra placentária, a média de células coradas pelo anticorpo anti-CD68 foi de 22±18 para o grupo GVAG e de 20±16 para o grupo GCES. CONCLUSÕES: não houve diferenças significantes no percentual de macrófagos (CD68+) em associação com o trabalho de parto.


PURPOSE: to verify the amount of CD68+ cells in chorionic villosities in placentae from gestations submitted or not to labor. METHODS: transversal study with healthy near-term pregnant women, among whose placentae, 31 have been examined by immunohistochemical technique. Twenty placentae were obtained after vaginal delivery (VAGG) and eleven after elective cesarean sections (CESG). Slides were prepared with chorionic villosities samples and labeled with anti-CD68 antibody, specific for macrophages. Labeled and nonlabeled cells were counted inside the villosities. Non-parametric statistical tests were used for the analysis. RESULTS: among the 6,424 cells counted in the villosities' stroma from the 31 placentae, 1,135 cells (17.6%) were stained by the CD68+. The mean of cells labeled by the anti-CD68 was 22±18 for the VAGG group and 20±16 for the CESG, in each placentary sample. CONCLUSIONS: there were no significant differences in the percentage of macrophages (CD68+) in association with labor.


Subject(s)
Adult , Female , Humans , Pregnancy , Young Adult , Chorionic Villi , Labor, Obstetric , Macrophages , Cell Count , Macrophages/cytology , Placenta/cytology , Young Adult
12.
Article in English | WPRIM | ID: wpr-185543

ABSTRACT

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into lineages of mesenchymal tissues that are currently under investigation for a variety of therapeutic applications. The purpose of this study was to compare cytokine gene expression in MSCs from human placenta, cord blood (CB) and bone marrow (BM). The cytokine expression profiles of MSCs from BM, CB and placenta (amnion, decidua) were compared by proteome profiler array analysis. The cytokines that were expressed differently, in each type of MSC, were analyzed by real-time PCR. We evaluated 36 cytokines. Most types of MSCs had a common expression pattern including MIF (GIF, DER6), IL-8 (CXCL8), Serpin E1 (PAI-1), GROalpha(CXCL1), and IL-6. MCP-1, however, was expressed in both the MSCs from the BM and the amnion. sICAM-1 was expressed in both the amnion and decidua MSCs. SDF-1 was expressed only in the BM MSCs. Real-time PCR demonstrated the expression of the cytokines in each of the MSCs. The MSCs from bone marrow, placenta (amnion and decidua) and cord blood expressed the cytokines differently. These results suggest that cytokine induction and signal transduction are different in MSCs from different tissues.


Subject(s)
Bone Marrow Cells/cytology , Cytokines/genetics , Female , Fetal Blood/cytology , Gene Expression Profiling , Humans , Mesenchymal Stem Cells/cytology , Placenta/cytology , Pregnancy , Protein Array Analysis
13.
Medicina (B.Aires) ; 68(5): 405-410, sep.-oct. 2008. ilus
Article in Spanish | LILACS | ID: lil-633578

ABSTRACT

En la placenta humana, el sinciciotrofoblasto es la barrera que regula el transporte de nutrientes, solutos y agua entre la sangre materna y fetal. Dentro de este movimiento transepitelial se encuentra el del Na+, su contribución a la presión osmótica es fundamental en la regulación del volumen de líquido extracelular. El canal epitelial de sodio sensible al amiloride (ENaC) media el transporte de Na+ desde el lumen hacia el interior celular en numerosos epitelios absortivos. Está regulado por la aldosterona, vasopresina, catecolaminas, estrógenos y progesterona. Es bloqueado por el amiloride y sus análogos. Para su activación, diversas proteasas lo escinden en la membrana plasmática y esto a su vez es regulado por la aldosterona. El ENaC está expresado también en la placenta humana y aunque su función no es conocida, podría participar en la homeostasis de agua y electrolitos. El ENaC también es influenciado por el estado de las proteínas del citoesqueleto y los cambios en el volumen celular alteran a su vez a éste. De esta manera existe una relación entre el ENaC y el citoesqueleto. Además, las corrientes de Na+ por el ENaC y otros canales de sodio participan en la migración celular en células normales y cancerosas. Aquí presentamos evidencias que avalan la hipótesis que el ENaC es necesario para la migración celular en células BeWo, derivadas del trofoblasto humano, que sintetizan hormonas y expresan el ENaC. Las células BeWO han sido utilizadas como modelo experimental para estudiar el transporte en células de placenta.


The syncytiotrophoblast acts in human placenta as a transporting barrier regulating the transference of nutrients, solutes and water between maternal and fetal blood. This transepithelial transport involves movement of Na+ and its contribution to the osmotic pressure is an important determinant of the extracellular fluid volume. ENaC is a channel that mediates entry of Na+ from the luminal fluid into the cells in many reabsorbing epithelia; it is aldosterone, vasopressin, insulin and catecholamine-inducible, modulated by estrogens and progesterone and blocked by amiloride and its analogs. Multiple proteases are involved in the proteolytic processing and activation of ENaC subunits and aldosterone alters the protease-protease inhibitors balance. ENaC is also expressed in human placenta; although its function is not well known, the Na+ conductive properties may participate in electrolyte and extracellular volume homeostasis. The activity of ENaC channels and other ion channels and transporters is regulated by the state of actin filaments; on the other hand, changes in volume influence the actin cytoskeleton. Thus, there is an interaction between ENaC and components of the apical membrane cytoskeleton. In addition to their role in cellular homeostasis and electrical properties, Na+ currents through ENaC and other sodium channels are involved in cell migration, well documented in normal and cancer cells. In this work we presented evidences supporting the hypothesis that ENaC channels are required for the migration of BeWo cells, a human hormone-synthesizing trophoblastic cell line that express the three subunits of the ENaC channels. BeWo cell line has also been used as a model to investigate the placental transport mechanisms.


Subject(s)
Female , Humans , Pregnancy , Aldosterone/metabolism , Cell Movement/physiology , Epithelial Sodium Channels/metabolism , Placenta/cytology , Pre-Eclampsia/metabolism , Cell Line
14.
Rev. obstet. ginecol. Venezuela ; 68(3): 160-167, sept. 2008. ilus, tab
Article in Spanish | LILACS | ID: lil-522992

ABSTRACT

Estudiar la frecuencia, características anatomopatológicas y análisis de los factores de riesgo de embarazadas con placenta ácreta en la Maternidad “Concepción Palacios”en el lapso 1994 a 2004. Estudio retrospectivo y descriptivo, se revisaron los informes histológicos de las histerectomías obstétricas y de las historias clínicas de las embarazadas con diagnóstico de placenta ácreta, increta y percreta. Maternidad “Concepción Palacios ” de Caracas. Se encontraron 35 pacientes con placenta ácreta (85,71 por ciento) y 5 casos de placenta percreta (0,014 por ciento). Esto representa un 0,014 por ciento de los ingresos obstétricos y uno por 0,62 por ciento nacidos vivos. La mayoría de las pacientes tenían una edad entre 31 y 40 años y 3-4 partos y sin relación con las cesáreas previas. En el 57,14 por ciento no se encontró registro de control prenatal. Con respecto a edad de gestación el 54,29 por ciento tenía entre 21-36 semanas de embarazo al momento del parto y 78,57 por ciento de ellas ingresó en trabajo de parto. Se realizó cesárea segmentaria+histerectomía en 71,43 por ciento de los casos. El peso fetal y la talla fue mayor o igual que 2 501 g y 43 a 47 cm en la mayoría. Este estudio representa un aporte a esta rara complicación del embarazo. Se recomienda el empleo de los recursos tecnológicos actuales para el diagnóstico de esta patología durante el embarazo para reducir la morbilidad y mortalidad materna y perinatal.


Subject(s)
Humans , Female , Pregnancy , Middle Aged , Pregnancy, High-Risk , Placenta Accreta/pathology , Placenta/cytology , Obstetrics , Histological Techniques/methods
15.
Biol. Res ; 41(3): 261-270, 2008. ilus, tab, graf
Article in English | LILACS | ID: lil-511916

ABSTRACT

Several major vascular tissues, such as the aorta-gonad-mesonephros región (AGM), yolk sac, and fetal liver have been confirmed to possess hematopoietic function. Recently, the placenta has been demonstrated as another hematopoietic organ. However, it is not conclusive whether the placenta possesses hematopoietic ability. Therefore, we undertook a series of experiments to study the hematopoietic functions of placenta. Fetal blood circulation in the placenta is difficult to be eliminated and its interference in the study of placental hematopoiesis is inevitable. With the application of placental flushing, fetal blood contained in the placenta was eliminated. We then made the further study of placental hematopoiesis after the El2.5 placenta was flushed. Our studies showed that placental cells expressing Sca-1, CD117 and CD34 were mainly restricted to the embryonic vessels of E12.5 placenta. The results of fluorescence activated cell sorter (FACs) analysis and colony forming cells (CFC) assay demonstrated that both placenta and placental blood contained hematopoietic stem/progenitor cells (HS/PCs), including CFU-GMs, CFU-GEMMs, BFU-Es, and HPP-CFCs. The frequency of HS/PCs in the placenta was 2-3 times that of placental blood. Therefore, it is necessary to clear placental blood out of the placenta in the studies of the hematopoietic potential of placenta. The placenta still possessed the hematopoietic potential after the fetal blood is flushed out. These observations provide further evidences that the placenta is a hematopoietic organ, as has been proposed for other embryonic hematopoietic sites.


Subject(s)
Animals , Female , Mice , Pregnancy , Cell Separation/methods , Colony-Forming Units Assay/methods , Fetal Blood/cytology , Hematopoietic Stem Cells/cytology , Placenta/cytology
16.
Article in English | WPRIM | ID: wpr-84652

ABSTRACT

The human organic anion transporter 4 (hOAT4) has been identified as the fourth isoform of OAT family. hOAT4 contributes to move several negatively charged organic compounds between cells and their extracellular milieu. The functional characteristics and regulatory mechanisms of hOAT4 remain to be elucidated. It is well known that caveolin plays a role in modulating proteins having some biological functions. To address this issue, we investigated the co-localization and interaction between hOAT4 and caveolin-1. hOAT4 and caveolin-1 (mRNA and protein expression) were observed in cultured human placental trophoblasts isolated from placenta. The confocal microscopy of immuno-cytochemistry using primary cultured human trophoblasts showed hOAT4 and caveolin-1 were co-localized at the plasma membrane of the cell. This finding was confirmed by Western blot analysis using isolated caveolae-enriched membrane fractions and immune-precipitates from the trophoblasts. When synthesized cRNA of hOAT4 along with scrambled- or antisense-oligodeoxynucleotide (ODN) of Xenopus caveolin-1 were co-injected to Xenopus oocytes, the [3H]estrone sulfate uptake was significantly decreased by the co-injection of antisense ODN but not by scrambled ODN. These findings suggest that hOAT4 and caveolin-1 share a cellular expression in the plasma membrane and caveolin-1 up-regulates the organic anionic compound uptake by hOAT4 under the normal physiological condition.


Subject(s)
Animals , Caveolin 1/genetics , Cells, Cultured , Female , Humans , Immunohistochemistry , Immunoprecipitation , Microscopy, Confocal , Models, Biological , Oocytes/metabolism , Organic Anion Transporters/genetics , Placenta/cytology , Protein Binding , Reverse Transcriptase Polymerase Chain Reaction , Trophoblasts/cytology , Xenopus
17.
Braz. j. vet. res. anim. sci ; 38(5): 224-228, 2001. ilus
Article in Portuguese | LILACS | ID: lil-324323

ABSTRACT

Foram estudados os aspectos morfológicos de nove placentas de paca (Agouti paca, L., 1766) mediante análises em microscopia de luz e eletrônica de transmissäo dos fragmentos teciduais correspondentes à porçäo de maior conexäo placentária em diferentes fêmeas gestantes, nos estágios intermediário e final da prenhez. Realizamos este estudo, pois, aliada à necessidade da procura de novas espécies que atuem como modelos experimentais adequados, havia a disponibilidade deste roedor em nosso meio; por outro lado, o melhor conhecimento dos aspectos reprodutivos destes animais oferece subsídios ao estabelecimento de criatórios racionais desta espécie, uma vez que a preservaçäo deste vertebrado é necessária, além do grande interesse comercial em torno de sua carne. Os resultados mostraram que este roedor possui uma placenta do tipo vitelina e outra do tipo corioalantoidiana, sendo este órgäo do tipo hemocorial, labiríntico, que se apresenta histologicamente composto por lóbulos divididos em três regiöes distintas: o centro do lóbulo, o labirinto e o interlóbulo. Na regiäo do centro do lóbulo, verificou-se a presença de artérias e veias; e em sua regiäo periférica estavam presentes dois sistemas tubulares arranjados de forma paralela, onde as lacunas sangüíneas e os capilares estavam em íntimo contato, formando a regiäo do labirinto. O interlóbulo era composto de artérias e veias. O trofoblasto era o principal componente da placenta, que, independentemente da regiäo onde se encontrava, mostrava-se de natureza sincicial. Ultra-estruturalmente a barreira placentária da paca foi classificada como hemomonocorial


Subject(s)
Animals , Female , Pregnancy , Microscopy, Electron , Placenta/cytology , Placenta/ultrastructure , Animals, Wild
18.
Rev. obstet. ginecol. Venezuela ; 59(3): 181-7, sept. 1999. ilus
Article in Spanish | LILACS | ID: lil-270035

ABSTRACT

Estudiar la interacción de la matriz extracelular con membranas plasmáticas de células fetales y maternas con microscopía electrónica de trasmisión y microscopía electrónica de barrido complementada por histoquímica ultraestructural usando azul alcián. Imágenes simultáneas de microfotografías con microscopía electrónica de trasmisión y microscopía electrónica de barrido son correlacionadas en sectores de membranas con relación a la matriz extracelular teñida con azul alcián. Centro de Investigación y Análisis Docente Asistencial del Núcleo Aragua. Facultad de Ciencias de la Salud. Universidad de Carabobo. Maracay-Venezuela. Microfilamentos conectan matriz hipoplasmática con matriz extracelular por intermedio de la membrana. Matriz extracelular de aspecto gránulo-filamentoso; se notó en dos tonalidades contrastadas, granulos electrón densos de células deciduales o trofoblásticas se observan en la periferia celular. Fibrina, colágena degenerada, fibrinoide y gránulos de diversos tamaños conforman una red compleja en el espacio extracelular. Fibrinoide tipo matriz fue reactivo al azul alcián y conforma parte del espacio extracelular observado simultáneamente con imágenes de microscopía electónica de trasmisión y microscopía electrónica de barrido a baja resolución, donde reacciones fisiológicas son de notable importancia clínica


Subject(s)
Humans , Female , Pregnancy , Cells/classification , Extracellular Matrix/physiology , Fetus , Microscopy, Electron, Scanning/methods , Mothers , Placenta/cytology
19.
Indian J Exp Biol ; 1999 Aug; 37(8): 758-61
Article in English | IMSEAR | ID: sea-61836

ABSTRACT

The artificially induced rat deciduoma serves as a model to study cellular changes associated with implantation in the endometrium. The stromal cells differentiate to form two types of decidual cells and are restricted to specific anatomical sites of the uterus. Programmed cell death starts in the antimesometrial area and expression of glutathione-S-transferase, an antioxidant enzyme, enhances in these cells as the deciduoma enters the regressive phase. The enzyme activity is significantly high compared with that of mesometrial decidual cells. Similarly, lipid peroxide content of antimesometrial decidual cells is high during this phase. DNA fragmentation, a feature of cells undergoing programmed cell death, is initiated in the antimesometrial area during regression of deciduoma.


Subject(s)
Animals , Apoptosis , Placenta/cytology , Rats , Rats, Wistar
20.
Rev. obstet. ginecol. Venezuela ; 57(2): 91-5, jul. 1997. ilus
Article in Spanish | LILACS | ID: lil-230605

ABSTRACT

Se realizó la descripción ultraestructural del fibroblasto de la placa basal de la placenta humana a término con técnicas de microscopia electrónica de transmisión. Dos condiciones de fibroblastos fueron encontradas: unos metabólicamente activos y otros degenerados. Los observados en el tejido conjuntivo superficial, debajo del sincitio, presentaron organelas bien preservadas y los localizados en las bandas de Nitabuch emvidenciaron cambios degenerativos. Se encontraron partículas de glucógeno alfa y ß en la matriz hialoplaásmica. Estos resultados indican que muchos fibroblastos mantienen, hasta el final del embrazo, su actividad de síntesis, mientras que otros sufren involución. Esto puede tener una gran importancia clínica para comprender algunos aspectos del desprendimiento placentario, debido a que las vellosidades del anclaje suelen empotrarse en el conjuntivo superficial


Subject(s)
Humans , Female , Fibroblasts/cytology , Fibroblasts/ultrastructure , Microscopy, Electron/methods , Microscopy, Electron , Placenta/cytology , Placenta/ultrastructure , Pregnancy
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