Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Reproduction ; 150(2): 115-25, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26021997

RESUMO

The human endometrium is a fertility-determining tissue and a target of steroid hormones' action. Endocrine disruptors (EDs) can exert adverse effects on the physiological function of the decidua at the maternal-fetal interface. We examined the potential effects of an ED, bisphenol A (BPA), on endometrial maturation/decidualization, receptivity, and secretion of decidual factors (biomarkers). In vitro decidualized, endometrial stromal cells from six hysterectomy specimens were treated with 1  pM-1  µM of BPA, for 24  h and assessed for cell viability and proliferation. Three non-toxic concentrations of BPA (1  µM, 1  nM, and 1  pM) were selected to study its influence on secretion of cell decidualization biomarkers (IGF-binding protein and decidual prolactin (dPRL)), macrophage migration inhibitory factor (MIF) secretion, and hormone receptors' expression (estrogen receptors (ERα and ERß); progesterone receptors (PRA and PRB); and human chorionic gonadotropin (hCG)/LH receptor (LH-R)). The results showed a decrease in cell viability (P<0.001) in response to BPA at the level of 1  mM. At the non-toxic concentrations used, BPA perturbed the expression of ERα, ERß, PRA, PRB, and hCG/LH-R (P<0.05). Furthermore, 1  µM of BPA reduced the mRNA transcription of dPRL (P<0.05). Secretion of MIF was stimulated by all BPA treatments, the lowest concentration (1  pM) being the most effective (P<0.001). The multi-targeted disruption of BPA on decidual cells, at concentrations commonly detected in the human population, raises great concern about the possible consequences of exposure to BPA on the function of decidua and thus its potential deleterious effect on pregnancy.


Assuntos
Compostos Benzidrílicos/toxicidade , Decídua/citologia , Decídua/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Antimetabólitos/farmacologia , Biomarcadores/análise , Biomarcadores/metabolismo , Bromodesoxiuridina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Decídua/metabolismo , Endométrio/citologia , Endométrio/efeitos dos fármacos , Endométrio/crescimento & desenvolvimento , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Ciclo Menstrual/efeitos dos fármacos , Gravidez , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
2.
Am J Physiol Cell Physiol ; 305(9): C931-40, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23948708

RESUMO

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 Galß1-3GalNAc) 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 Galß1-3GalNAc epitope at low oxygen tension. Our results support a fundamental role of oxygen tension in modulating glycosylation of proteins during placental development.


Assuntos
Epitopos/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Oxigênio/fisiologia , Placenta/metabolismo , Sialiltransferases/metabolismo , Linhagem Celular Transformada , Feminino , Humanos , Técnicas de Cultura de Órgãos , Oxigênio/farmacologia , Placenta/efeitos dos fármacos , Gravidez , beta-Galactosídeo alfa-2,3-Sialiltransferase
3.
Am J Physiol Endocrinol Metab ; 298(3): E411-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20173014

RESUMO

Successful pregnancy involves a series of events, most of them mediated by hormones and cytokines. Estrogens, besides being important for placental growth and embryo development, have a marked effect on the immune system exerting either pro- or anti-inflammatory properties. Numerous studies suggest that estrogens directly affect cellular function, including cytokine production. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine involved in pregnancy, particularly during the earlier stages of placentation. Since reports on mice have shown that estrogens modulate MIF, herein we investigated the effect of estrogens on human placental MIF. By using an in vitro model of first-trimester chorionic villous explants, we found that 17beta-estradiol (E(2)) was able to modulate the release of MIF in a dose-dependent manner (10(-12) vs. 10(-9) M, P < 0.05; 10(-9) vs. 10(-5) M, P < 0.05; 10(-12) vs. 10(-5) M, P < 0.001). Unlike MIF release, no significant change in tissue MIF protein or MIF mRNA was observed. We showed evidence that E(2) concentrations (10(-9) and 10(-5) M) act on placental tissue downregulating the mRNA and protein expression of the ATP-binding cassette transporter protein A1, a membrane transporter involved in MIF secretion. These findings emphasize the mutual cooperation between hormones and cytokines and suggest that increasing estrogen levels with advancing gestation may have a major role in regulating placental MIF secretion.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Estradiol/administração & dosagem , Fatores Inibidores da Migração de Macrófagos/metabolismo , Placenta/metabolismo , Primeiro Trimestre da Gravidez/fisiologia , Gravidez/metabolismo , Transdução de Sinais/fisiologia , Transportador 1 de Cassete de Ligação de ATP , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Placenta/efeitos dos fármacos , Primeiro Trimestre da Gravidez/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
4.
Int J Oncol ; 30(1): 161-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17143525

RESUMO

Among marine sessile organisms, sponges (Porifera) are the major producers of bioactive secondary metabolites that defend them against predators and competitors and are used to interfere with the pathogenesis of many human diseases. Some of these biological active metabolites are able to influence cell survival and death, modifying the activity of several enzymes involved in these cellular processes. These natural compounds show a potential anticancer activity but the mechanism of this action is largely unknown. In this study, we investigated the effects of two Mediterranean sponges, Agelas oroides and Petrosia ficiformis on the viability of human neuroblastoma cells. Upon treatment with the methanolic extract of Petrosia ficiformis, a marked cytotoxic effect was observed at any concentration or time of exposure. In contrast, a time- and dose-dependent effect was monitored for Agelas oroides that induced the development of apoptotic features and ROS production in LAN5 cells. These events were suppressed by calpeptin or zVAD and by vitamin C suggesting that the cell death caused by Agelas oroides was calpain- and caspase-dependent and of oxidative nature. Comet assay showed that this methanolic extract was not able to produce a genotoxic effect. Future studies will be applied to investigate the effect of isolated bioactive compounds from crude extract of this sponge which are potentially useful for cancer therapeutics.


Assuntos
Agelas/química , Sobrevivência Celular/efeitos dos fármacos , Petrosia/química , Extratos de Tecidos/farmacologia , Animais , Ácido Ascórbico/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio Cometa , Fluoresceína-5-Isotiocianato , Neuroblastoma/patologia , Espécies Reativas de Oxigênio/metabolismo
5.
Microsc Res Tech ; 70(11): 944-51, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17661369

RESUMO

Gamma-amino butyric acid (GABA) is believed to be the principal inhibitory neurotransmitter in the mammalian central nervous system, a function that has been extended to a number of invertebrate systems. The presence of GABA in the marine demosponge Chondrilla nucula was verified using immunofluorescence detection and high-pressure liquid chromatography. A strong GABA-like immunoreactivity (IR) was found associated with choanocytes, exopinacocytes, endopinacocytes lining inhalant, and exhalant canals, as well as in archaeocytes scattered in the mesohyl. The capacity to synthesize GABA from glutamate and to transport it into the vesicles was confirmed by the presence in C. nucula of glutamate decarboxylase (GAD) and vesicular GABA transporters (vGATs), respectively. GAD-like and vGAT-like IR show the same distribution as GABA-like IR. Supporting the similarity between sponge and mammalian proteins, bands with an apparent molecular weight of about 65-67 kDa and 57 kDa were detected using antibodies raised against mammalian GAD and vGAT, respectively. A functional metabotropic GABA(B)-like receptor is also present in C. nucula. Indeed, both GABA(B) R1 and R2 isoforms were detected by immunoblot and immunofluorescence. Also in this case, IR was found in choanocytes, exopinacocytes, and endopinacocytes. The content of GABA in C. nucula amounts to 1225.75 +/- 79 pmol/mg proteins and GABA is released into the medium when sponge cells are depolarized. In conclusion, this study is the first indication of the existence of the GABA biosynthetic enzyme GAD and of the GABA transporter vGAT in sponges, as well as the first demonstration that the neurotransmitter GABA is released extracellularly.


Assuntos
Poríferos/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Transporte Biológico Ativo , Cromatografia Líquida de Alta Pressão , Imunofluorescência , Glutamato Descarboxilase/metabolismo , Isoformas de Proteínas/metabolismo
6.
Biosens Bioelectron ; 25(9): 2095-100, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20227870

RESUMO

Technologies today available for the DNA detection rely on a combination of labeled probes hybridized to target sequences which are amplified by polymerase chain reaction (PCR). Direct detection methods that eliminate the requirement for both PCR and labeling steps could afford faster, cheaper and simpler devices for the analysis of small amounts of unamplified DNA. In this work we describe the results obtained in the ultrasensitive detection of non-amplified genomic DNA. We analyzed certified reference materials containing different amounts of genetically modified DNA by using a detection method which combines the nanoparticle-enhanced surface plasmon resonance imaging (SPRI) biosensing to the peptide nucleic acids (PNAs) improved selectivity and sensitivity in targeting complementary DNA sequences. The method allowed us to obtain a 41 zM sensitivity in targeting genomic DNA even in the presence of a large excess of non-complementary DNA.


Assuntos
DNA/análise , Nanopartículas Metálicas , Ressonância de Plasmônio de Superfície/métodos , Sequência de Bases , DNA/genética , DNA de Plantas/análise , DNA de Plantas/genética , DNA Recombinante/análise , DNA Recombinante/genética , Ouro , Ácidos Nucleicos Peptídicos , Plantas Geneticamente Modificadas/genética , Glycine max/genética , Ressonância de Plasmônio de Superfície/estatística & dados numéricos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa