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1.
Atmos Pollut Res ; 14(1): 101637, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36540303

RESUMO

Carbon neutrality, sustainable development and reducing our impact on the environment is the top priority in future measures. The COVID-19 pandemic brought challenges to every sector at a global scale but can provide valuable insight to reach these goals. The main objective of this work is to provide an integrated analysis of the impact of the COVID-19 pandemic, focused on energy and its related aspects, i.e., environment and costs. Mainland Portugal was used as a case study and two years were analysed, one pre pandemic (2019) and another post pandemic (2020). In 2020, the majority of sectors - Transport, Services, Industry and Agriculture & Fisheries - show a reduction of energy consumption, atmospheric emissions, carbon footprint and related monetary and social costs. In contrast, the Domestic sector presents an overall increase, with maximums of 25.4% in electricity consumption (during Spring), 0.72% in the PM10 (particulate matter) and NOx (nitrogen dioxides) emissions (in Summer), and 2.9% in carbon footprint (in Spring). The integrated analysis proposed in this work was crucial to identify the paths to a post pandemic world focused on the different aspects of sustainability - new concepts of mobility and workplace, as well as increased investment in energy performance and renewable energy sources. This study showed that changing our energy consumption patterns could significantly affect future greenhouse gas emissions, and contribute to the sustainable growth of the economy, while maintaining good progress towards climate-neutral goals.

3.
Energy Policy ; 159: 112644, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36246728

RESUMO

This study explores different energy consumption vectors during the first year of the COVID-19 pandemic in Portugal. Most of the workforce started working from home and resource consumption significantly shifted towards the domestic sector. The ensuing confinement protocols caused a shift in everyday life, which in turn significantly altered the energy supply and demand landscape. This event, although catastrophic in terms of loss of human life and economic development, can provide us with valuable data to study the potential of new strategies to achieve EU 2050 Energy goals. It was investigated whether the pandemic has opened a path and provided us with a partial answer to decarbonization in the form of home office practices as a possible energy efficiency measure. The present study shows that, in Portugal, there was a 15.7% reduction of primary energy consumption (accounting for electricity, natural gas and transport fuels) compared to 2019. The data suggest that actions targeting reduced mobility, such as home office practices and the decentralization of the workforce, could be a relevant energy efficiency measure.

5.
Biomed Res Int ; 2015: 487256, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25866786

RESUMO

Cellular swelling is controlled by an active mechanism of cell volume regulation driven by a Na(+)/K(+)-dependent ATPase and by aquaporins which translocate water along the osmotic gradient. Na(+)/K(+)-pump may be blocked by ouabain, a digitalic derivative, by inhibition of ATP, or by drastic ion alterations of extracellular fluid. However, it has been observed that some tissues are still able to control their volume despite the presence of ouabain, suggesting the existence of other mechanisms of cell volume control. In 1977, by correlating electron microscopy observation with ion and water composition of liver slices incubated in different metabolic conditions in the presence or absence of ouabain, we observed that hepatocytes were able to control their volume extruding water and recovering ion composition in the presence of ouabain. In particular, hepatocytes were able to sequester ions and water in intracellular vesicles and then secrete them at the bile canaliculus pole. We named this "vesicular mechanism of cell volume control." Afterward, this mechanism has been confirmed by us and other laboratories in several mammalian tissues. This review summarizes evidences regarding this mechanism, problems that are still pending, and questions that need to be answered. Finally, we shortly review the importance of cell volume control in some human pathological conditions.


Assuntos
Tamanho Celular , Vesículas Citoplasmáticas/metabolismo , Ouabaína/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Humanos , Transporte de Íons/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo
6.
Cell Death Discov ; 1: 15014, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551448

RESUMO

Muscle LIM protein (MLP) is a microtubule-associated protein expressed in cardiac and muscle tissues that belongs to the cysteine-rich protein (CSRP/CRP) family. MLP has a central role during muscle development and for architectural maintenance of muscle cells. However, muscle cells rely on autophagy during differentiation and for structural maintenance. To study the role of MLP in autophagy, we have used C2C12 mouse myoblasts silenced or overexpressing MLP. Our results show that MLP contributes to the correct autophagosome formation and flux by interacting with LC3 as demonstrated by co-immunoprecipitation and PLA assay. In fact, MLP silencing results in decreased LC3-II staining and absent degradation of long-lived proteins. Moreover, MLP silencing impaired myoblasts differentiation as measured by decreased expression of MyoD1, MyoG1 and myosin heavy chain. Ultrastructural analysis revealed the presence of large empty autophagosomes in myoblasts and multimembranous structures in myotubes from MLP-silenced clones. Impaired autophagy in MLP-silenced cells resulted in increased susceptibility to apoptotic cell death. In fact, treatment of MLP-silenced C2C12 myoblasts and myotubes with staurosporine resulted in increased caspase-3 and PARP cleavage as well as increased percentage of cell death. In conclusion, we propose that MLP regulates autophagy during muscle cell differentiation or maintenance through a mechanism involving MLP/LC3-II interaction and correct autophagosome formation.

7.
Curr Med Chem ; 21(9): 1146-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24304280

RESUMO

Reprogramming technologies have been developed to revert somatic differentiated cells into pluripotent stem cells that can be differentiated into different lineages potentially useful in stem cell therapy. Reprogramming methods have been progressively refined to increase their efficiency, to obtain a cell population suitable for differentiation, and to eliminate viral plasmid which could be responsible for many unwanted side-effects when used in personalized medicine. All these methods are aimed to introduce into the cell genes or mRNAs encoding a set of four transcription factors (OCT- 4, SOX-2, KLF-4 and c-MYC) or a set of three lincRNAs (large intragenic non-coding RNAs) acting downstream of the reprogramming transcription factors OCT-4, SOX-2 and NANOG. Translational clinical applications in human pathologies and in developmental, repair and cancer biology have been numerous. Cancer cells can be, at least in principle, reprogrammed into a normal phenotype. This is a recently raised issue, rapidly advancing in many human tumors, especially endocrine-related cancers, such as breast, prostate and ovarian ca. The present review aims to describe basic phenomena observed in reprogramming tumor cells and solid tumors and to discuss their meaning in human hormone-related cancers. We will also discuss the fact that some of the targeted transcription factors are "normally" activated in a number of physiological processes, such as morphogenesis, hypoxia and wound healing, suggesting an in vivo role of reprogramming for development and homeostasis. Finally, we will review concerns and warnings raised for in vivo reprogramming of human tumors and for the use of induced pluripotent stem cells (iPSCs) in human therapy.


Assuntos
Reprogramação Celular , Sistema Endócrino , Neoplasias/metabolismo , Animais , Diferenciação Celular , Humanos , Neoplasias/patologia , Células-Tronco Neoplásicas/metabolismo
8.
Int J Immunopathol Pharmacol ; 26(1 Suppl): 11-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24046945

RESUMO

Today adipose tissue is not just considered as the primary energy storage organ, but it is also recognized as an important endocrine tissue and an abundant source of mesenchymal stem cells (adipose-derived stem cells, ASCs). During the last decade, several studies have provided preclinical data on the safety and efficacy of ASCs, supporting their use in cell-based therapy for regenerative medicine purposes. Little is known about the effect of obesity on ASCs properties. Since ASCs differentiation and proliferation are determined by their niche, the differences in body fat distribution and the obesity-related co-morbidities may have several consequences. In this study we compared ASCs of subcutaneous adipose tissue from obese (obS-ASCs) and non-obese (nS-ASCs) donors in order to compare their immunophenotype and osteogenic and adipogenic potential. Moreover, in order to evaluate the possible difference between subcutaneous and visceral fat, obS-ASCs were also compared to ASCs derived from visceral adipose tissue of the same obese donors (obV-ASCs). Our results show that subcutaneous and visceral ASCs derived from obese donors have an impaired cell proliferation, clonogenic ability and immunophenotype. Nevertheless, obS-ASCs are able to differentiate toward osteogenic and adipogenic lineages, although to a small extent with respect to non-obese donors, whereas obV-ASCs lose most of their stem cell characteristics, including multi-differentiation potential. Taken together our findings confirm that not all ASCs present the same behavior, most likely due to their biological microenvironment in vivo. The specific stimuli which can play a key role in ASCs impairment, including the effects of the obesity-related inflammation, should be further investigated to have a complete picture of the phenomenon.


Assuntos
Adipogenia , Gordura Intra-Abdominal/citologia , Obesidade/patologia , Osteogênese , Células-Tronco/citologia , Gordura Subcutânea/citologia , Adulto , Diferenciação Celular , Proliferação de Células , Feminino , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/análise , Masculino , Pessoa de Meia-Idade
9.
J Biol Regul Homeost Agents ; 27(2): 497-507, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23830399

RESUMO

Sirtuins are NAD+-dependent lysine deacetylases. Sirtuins acquired worldwide attention because of their ability to increase yeast, flies, worms and mice lifespan. Recently, this assumption has been challenged. However, their beneficial role on the quality of ageing is widely accepted. In this work we aimed to study how and if sirtuins expression and activity levels varies in function of age and, in the case of young subjects, of exercise. Fifteen blood donors of different ages and fifteen athletes of the Italian rowing male team were enrolled and peripheral blood mononuclear cells (PBMCs) isolated from blood samples. Our results show that sirtuins deacetylases activity measured in PBMCs increases from 18 to 40 years of age and then decreases during the following 20 years. Moreover, physical exercise in professional athletes can upregulate sirtuin activity. Thus, for the first time in humans, we demonstrate that sirtuin activity is a function of age and can be altered through physical exercise.


Assuntos
Exercício Físico , Sirtuínas/metabolismo , Fatores Etários , Atletas , Doadores de Sangue , Humanos , Leucócitos Mononucleares/enzimologia , Masculino
10.
Cell Death Differ ; 19(11): 1815-25, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22595756

RESUMO

Mitochondrial sirtuin 3 (SIRT3) mediates cellular resistance toward various forms of stress. Here, we show that in mammalian cells subjected to hypoxia and staurosporine treatment SIRT3 prevents loss of mitochondrial membrane potential (ΔΨ(mt)), intracellular acidification and reactive oxygen species accumulation. Our results indicate that: (i) SIRT3 inhibits mitochondrial permeability transition and loss of membrane potential by preventing HKII binding to the mitochondria, (ii) SIRT3 increases catalytic activity of the mitochondrial carbonic anhydrase VB, thereby preventing intracellular acidification, Bax activation and apoptotic cell death. In conclusion we propose that, in mammalian cells, SIRT3 has a central role in connecting changes in ΔΨ(mt), intracellular pH and mitochondrial-regulated apoptotic pathways.


Assuntos
Apoptose/efeitos dos fármacos , Hipóxia Celular , Inibidores Enzimáticos/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Sirtuína 3/metabolismo , Estaurosporina/farmacologia , Anidrases Carbônicas/metabolismo , Linhagem Celular Tumoral , Células HeLa , Hexoquinase/metabolismo , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Células K562 , Mitocôndrias/metabolismo , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/genética , Proteína X Associada a bcl-2/metabolismo
11.
Life Sci ; 90(21-22): 825-30, 2012 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22480518

RESUMO

AIMS: In this study, we present an innovative therapy using stem cells that were obtained from the peripheral blood of racehorses affected by uninduced superficial digital flexor tendon (SDFT) injuries. MAIN METHODS: Blood-derived stem cells (BDSCs) were generated from the blood samples of three horses in the presence of macrophage colony-stimulating factor (M-CSF). The racehorses received a single autologous BDSC treatment, which resulted in the successful repair of the tendons injuries. KEY FINDINGS: The results demonstrated that the BDSCs injection into the damaged tendon stimulated the regeneration of normal tissue. Furthermore, a relationship may exist between the speed and the quality of new tissue formation and the welfare and management of the treated animals. SIGNIFICANCE: This study demonstrates that stem cell technology offers new tools for tissue repair that in many cases is considered incurable, and provides additional evidence that BDScs injections increase the speed and quality of the regeneration process in different animal tissues.


Assuntos
Doenças dos Cavalos/terapia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Transplante de Células-Tronco/métodos , Traumatismos dos Tendões/terapia , Animais , Feminino , Doenças dos Cavalos/patologia , Cavalos/lesões , Masculino , Regeneração , Transplante de Células-Tronco/veterinária , Traumatismos dos Tendões/veterinária , Fatores de Tempo , Resultado do Tratamento
13.
Cell Death Differ ; 17(6): 962-74, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20057503

RESUMO

Mutations in the PINK1 gene cause autosomal recessive Parkinson's disease. The PINK1 gene encodes a protein kinase that is mitochondrially cleaved to generate two mature isoforms. In addition to its protective role against mitochondrial dysfunction and apoptosis, PINK1 is also known to regulate mitochondrial dynamics acting upstream of the PD-related protein Parkin. Recent data showed that mitochondrial Parkin promotes the autophagic degradation of dysfunctional mitochondria, and that stable PINK1 silencing may have an indirect role in mitophagy activation. Here we report a new interaction between PINK1 and Beclin1, a key pro-autophagic protein already implicated in the pathogenesis of Alzheimer's and Huntington's diseases. Both PINK1 N- and C-terminal are required for the interaction, suggesting that full-length PINK1, and not its cleaved isoforms, interacts with Beclin1. We also demonstrate that PINK1 significantly enhances basal and starvation-induced autophagy, which is reduced by knocking down Beclin1 expression or by inhibiting the Beclin1 partner Vps34. A mutant, PINK1(W437X), interaction of which with Beclin1 is largely impaired, lacks the ability to enhance autophagy, whereas this is not observed for PINK1(G309D), a mutant with defective kinase activity but unaltered ability to bind Beclin1. These findings identify a new function of PINK1 and further strengthen the link between autophagy and proteins implicated in the neurodegenerative process.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Autofagia , Proteínas de Membrana/metabolismo , Proteínas Quinases/metabolismo , Proteínas Reguladoras de Apoptose/análise , Proteína Beclina-1 , Linhagem Celular Tumoral , Células HeLa , Humanos , Proteínas de Membrana/análise , Mitocôndrias/química , Mitocôndrias/ultraestrutura , Mutação , Proteínas Quinases/análise , Proteínas Quinases/genética , Deleção de Sequência , Técnicas do Sistema de Duplo-Híbrido
14.
J Int Med Res ; 37(5): 1321-35, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19930837

RESUMO

Guidelines for osteoarthritis (OA) management recommend paracetamol (acetaminophen) as the most appropriate first-line analgesic for mild to moderate pain. Standard paracetamol requires four times daily dosing. Drug compliance and convenience are inversely related to daily dose frequency. Compliance is a pivotal component of the successful management of OA pain and is influenced by patient preferences or beliefs. The added convenience of three times daily dosing may enhance compliance and, therefore, pain relief. This multicentre, randomized, open-label, two-way crossover, phase IV study is the first to evaluate patient preference with a sustained-release paracetamol tablet formulation designed for three times daily dosing. Compared with standard paracetamol tablets dosed four times daily, the sustained-release formulation was preferred in a 2:1 ratio, provided better overall joint pain relief, resulted in higher levels of satisfaction in subjects with OA of the knee and has the potential to improve patient compliance and, therefore, pain control.


Assuntos
Acetaminofen/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Preferência do Paciente , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Comprimidos
15.
Biomed Pharmacother ; 63(10): 742-53, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19917524

RESUMO

Thyroid dysfunction, however mild, can significantly affect the cardiovascular (CV) system. The effects of thyroid hormones may be viewed as genomic and non-genomic, with the former occurring over a longer time scale and both affecting structural and functional proteins in CV tissue. As the interplay between thyroid function and the CV system becomes elucidated, particularly in the context of a system biology approach, the heart failure phenotype is better understood. Symptomatology is related to disturbance in inotropic and chronotropic function. Moreover, biochemical changes reflected by thyroid function testing with the non-thyroidal illness syndrome can prognosticate and guide therapy in heart failure. In addition, empiric treatment with thyroid hormone analogues or T3 represent emergent and highly controversial interventions.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças da Glândula Tireoide/complicações , Hormônios Tireóideos/metabolismo , Animais , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/fisiopatologia , Genômica , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Humanos , Biologia de Sistemas , Testes de Função Tireóidea , Hormônios Tireóideos/administração & dosagem , Hormônios Tireóideos/uso terapêutico
16.
J Cell Physiol ; 219(1): 69-76, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19067321

RESUMO

The molecular mechanism by which the lipido-sterolic extract of Serenoa repens (LSESr, Permixon) affects prostate cells remains to be fully elucidated. In androgen-independent PC3 prostate cancer cells, the LSESr-induced effects on proliferation and apoptosis were evaluated by counting cells and using a FACScan cytofluorimeter. PC3 cells were stained with JC-1 dye to detect mitochondrial membrane potential. Cell membrane lipid composition was evaluated by thin layer chromatography and gas chromatographic analysis. Akt phosphorylation was analyzed by Western blotting and cellular ultrastructure through electron microscopy. LSESr (12.5 and 25 microg/ml) administration exerted a biphasic action by both inhibiting proliferation and stimulating apoptosis. After 1 h, it caused a marked reduction in the mitochondrial potential, decreased cholesterol content and modified phospholipid composition. A decrease in phosphatidylinositol-4,5-bisphosphate (PIP2) level was coupled with reduced Akt phosphorylation. After 24 h, all of these effects were restored to pre-treatment conditions; however, the saturated (SFA)/unsaturated fatty acid (UFA) ratio increased, mainly due to a significant decrease in omega 6 content. The reduction in cholesterol content could be responsible for both membrane raft disruption and redistribution of signaling complexes, allowing for a decrease of PIP2 levels, reduction of Akt phosphorylation and apoptosis induction. The decrease in omega 6 content appears to be responsible for the prolonged and more consistent increase in the apoptosis rate and inhibition of proliferation observed after 2-3 days of LSESr treatment. In conclusion, LSESr administration results in complex changes in cell membrane organization and fluidity of prostate cancer cells that have progressed to hormone-independent status.


Assuntos
Antagonistas de Androgênios/farmacologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Preparações de Plantas/farmacologia , Neoplasias da Próstata , Serenoa/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos dos fármacos , Membrana Celular/química , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Fitoterapia , Preparações de Plantas/química , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
17.
Cell Death Differ ; 13(12): 2068-78, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16729030

RESUMO

Mutated huntingtin (htt) is ubiquitously expressed in tissues of Huntington's disease (HD) patients. In the brain, the mutated protein leads to neuronal cell dysfunction and death, associated with formation of htt-positive inclusions. Given increasing evidence of abnormalities in HD skeletal muscle, we extensively analyzed primary muscle cell cultures from seven HD subjects (including two unaffected mutation carriers). Myoblasts from presymptomatic and symptomatic HD subjects showed cellular abnormalities in vitro, namely mitochondrial depolarization, cytochrome c release, increased caspase-3, -8, and -9 activities, and defective cell differentiation. Another notable feature was the formation of htt inclusions in differentiated myotubes. This study helps to advance current knowledge about the downstream effects of the htt mutation in human tissues. Further applications may include drug screening using this human cellular model.


Assuntos
Apoptose/fisiologia , Doença de Huntington/patologia , Doença de Huntington/fisiopatologia , Corpos de Inclusão/patologia , Músculo Esquelético/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Citocromos c/genética , Citocromos c/metabolismo , Regulação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Humanos , Proteína Huntingtina , Corpos de Inclusão/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Músculo Esquelético/química , Músculo Esquelético/fisiopatologia , Mutação , Mioblastos/metabolismo , Mioblastos/patologia , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética
18.
Am J Reprod Immunol ; 52(3): 185-91, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15373757

RESUMO

PROBLEM: Nitric oxide (NO), an important mediator of the inflammatory response, is involved in several reproductive processes including pregnancy and labor. Uterus, placenta and fetal membranes are significant sources of NO. Presently, there is no information on factors regulating NO production by fetal membranes. METHOD OF STUDY: Human fetal membranes at term gestation were cultured for 24 hr in the presence of oxytocin. The concentrations of NO metabolites nitrites in culture medium were determined by the Griess reaction. The presence of inducible nitric oxide synthase (iNOS) was determined by reverse transcriptase-polymerase chain reaction and Western blot. RESULTS: Oxytocin increased nitrite release by fetal membranes. Messenger ribonucleic acid iNOS expression was also enhanced by oxytocin. These effects were more marked in tissues obtained after labor than before labor. CONCLUSIONS: Oxytocin exerts an overall stimulatory effect on NO release by fetal membranes. This action might be of relevance in the biomolecular processes leading to parturition.


Assuntos
Membranas Extraembrionárias/efeitos dos fármacos , Membranas Extraembrionárias/metabolismo , Óxido Nítrico/metabolismo , Ocitocina/farmacologia , Parto/metabolismo , Dimerização , Feminino , Humanos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Nitritos/metabolismo , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos
20.
J Reprod Immunol ; 56(1-2): 123-36, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12106888

RESUMO

Inflammatory cytokines can play an important role in the biomolecular processes leading to labour by regulating prostaglandin production in intrauterine tissues. In the setting of intrauterine infection, an increased production of these cytokines by placenta, decidua and fetal membranes occurs and is responsible for the onset and maintenance of preterm labour. However, the factors involved in the control of cytokine release by these tissues in normal pregnancy at term are still largely unknown. We investigated the possibility that the synthesis and release of tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) by human fetal membranes at term gestation is regulated by several hormones potentially involved either in the maintenance of pregnancy or in the parturitional process. In the present study, the effects of hydrocortisone, progesterone and oxytocin on TNF-alpha and TGF-beta1 release by explants of fetal membranes at term gestation were evaluated. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assess the effect of the above hormones on mRNA expression; TNF-alpha and TGF-beta1 release in culture medium was quantitifed by ELISA assays. Results show that both tissue mRNA expression for TNF-alpha and TNF-alpha release in culture medium were significantly increased by oxytocin, but not by hydrocortisone and progesterone. On the contrary, all the hormones tested increased both tissue TGF-beta1 mRNA expression and release in culture medium. These findings suggest that TNF-alpha and TGF-beta1 production by human fetal membranes in uncomplicated pregnancy at term is selectively modulated by oxytocin, hydrocortisone and progesterone.


Assuntos
Membranas Extraembrionárias/imunologia , Hidrocortisona/farmacologia , Ocitocina/farmacologia , Progesterona/farmacologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Necrose Tumoral alfa/biossíntese , Feminino , Humanos , Gravidez , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa/genética
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