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1.
Int J Mol Sci ; 23(2)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35054881

RESUMO

Increased maternal food intake is considered a normal pregnancy adjustment. However, the overavailability of nutrients may lead to dysregulated fetal development and increased adiposity, with long-lasting effects on offspring in later life. Several gut-hormone molecules regulate maternal appetite, with both their orexigenic and anorectic effects being in a state of sensitive equilibrium. The aim of this manuscript is to systematically review literature on the effects of maternal gut-hormone molecules on fetal growth and metabolism, birth weight and the later metabolic health of offspring. Maternal serum ghrelin, leptin, IGF-1 and GLP-1 appear to influence fetal growth; however, a lack of consistent and strong correlations of maternal appetite axis hormones with birth weight and the concomitant correlation with fetal and birth waist circumference may suggest that these molecules primarily mediate fetal energy deposition mechanisms, preparing the fetus for survival after birth. Dysregulated intrauterine environments seem to have detrimental, sex-dependent effects on fetal energy stores, affecting not only fetal growth, fat mass deposition and birth weight, but also future metabolic and endocrine wellbeing of offspring.


Assuntos
Apetite , Desenvolvimento Fetal , Feto/metabolismo , Complicações na Gravidez , Peso ao Nascer , Feminino , Hormônios Gastrointestinais , Humanos , Obesidade , Gravidez
2.
Gynecol Oncol ; 160(1): 148-160, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33190932

RESUMO

BACKGROUND: Lynch syndrome is an inherited genetic condition that is associated with an increased risk of cancer, including endometrial and colorectal cancer. We assessed the test accuracy of immunohistochemistry and microsatellite instability-based testing (with or without MLH1 promoter methylation testing) for Lynch syndrome in women with endometrial cancer. METHODS: We conducted a systematic review of literature published up to August 2019. We searched bibliographic databases, contacted experts and checked reference lists of relevant studies. Two reviewers conducted each stage of the review. RESULTS: Thirteen studies were identified that included approximately 3500 participants. None of the studies was at low risk of bias in all domains. Data could not be pooled due to the small number of heterogeneous studies. Sensitivity ranged from 60.7-100% for immunohistochemistry, 41.7-100% for microsatellite instability-based testing, and 90.5-100% for studies combining immunohistochemistry, microsatellite instability-based testing, and MLH1 promoter methylation testing. Specificity ranged from 60.9-83.3% (excluding 1 study with highly selective inclusion criteria) for immunohistochemistry, 69.2-89.9% for microsatellite instability-based testing, and 72.4-92.3% (excluding 1 study with highly selective inclusion criteria) for testing strategies that included immunohistochemistry, microsatellite instability-based testing, and MLH1 promoter methylation. We found no statistically significant differences in test accuracy estimates (sensitivity, specificity) in head-to-head studies of immunohistochemistry versus microsatellite instability-based testing. Reported test failures were rare. CONCLUSIONS: Sensitivity of the index tests were generally high, though most studies had much lower specificity. We found no evidence that test accuracy differed between IHC and MSI based strategies. The evidence base is currently small and at high risk of bias.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias do Endométrio/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Instabilidade de Microssatélites
3.
Prenat Diagn ; 40(4): 454-462, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31834626

RESUMO

OBJECTIVE: To evaluate the test accuracy of non-invasive prenatal testing (NIPT) for fetal trisomy 21, 18, and 13 using cell-free (cf) DNA analysis in maternal plasma with microarray quantitation. METHOD: Systematic review and meta-analysis. Searches in MEDLINE, Pre-MEDLINE, EMBASE, Web of Science, and the Cochrane Library to 09.07.2018. RESULTS: Five studies analyzing 3074 samples, including 187 trisomy 21, 43 trisomy 18, and 19 trisomy 13 cases, were identified. Risk of bias was high in all studies, introduced particularly by exclusions from analysis and by the role of the sponsor. Sensitivity of microarray-based cfDNA testing was 99.5% (95%CI 96.3%-99.9%) for trisomy 21, 97.7% (95%CI 87.9%-99.6%) for trisomy 18, and 100% (95%CI 83.2%-100%) for trisomy 13. Specificity was 100% (95% CI 99.87%-100%) for trisomy 21, 99.97% (95%CI 99.81%-99.99%) for trisomy 18, and 99.97% (95%CI 99.81%-99.99%) for trisomy 13. Pooled test failure rate was 1.1%. A direct comparison of microarray- and sequencing-based cfDNA found equivalent test accuracy. CONCLUSION: Included studies suggest that NIPT using microarray-based cfDNA testing has high sensitivity and specificity for detecting fetal trisomy 21, 18, and 13. However, the evidence base is small and at high risk of bias.


Assuntos
Ácidos Nucleicos Livres/análise , Síndrome de Down/diagnóstico , Teste Pré-Natal não Invasivo/métodos , Síndrome da Trissomia do Cromossomo 13/diagnóstico , Síndrome da Trissomía do Cromossomo 18/diagnóstico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Análise em Microsséries , Gravidez , Sensibilidade e Especificidade , Análise de Sequência de DNA
6.
Biochim Biophys Acta ; 1842(9): 1762-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24970747

RESUMO

Telomerase reverse transcriptase (TERT) is a key component of the telomerase complex. By lengthening telomeres in DNA strands, TERT increases senescent cell lifespan. Mice that lack TERT age much faster and exhibit age-related conditions such as osteoporosis, diabetes and neurodegeneration. Accelerated telomere shortening in both human and animal models has been documented in conditions associated with insulin resistance, including T2DM. We investigated the role of TERT, in regulating cellular glucose utilisation by using the myoblastoma cell line C2C12, as well as primary mouse and human skeletal muscle cells. Inhibition of TERT expression or activity by using siRNA (100nM) or specific inhibitors (100nM) reduced basal 2-deoxyglucose uptake by ~50%, in all cell types, without altering insulin responsiveness. In contrast, TERT over-expression increased glucose uptake by 3.25-fold. In C2C12 cells TERT protein was mostly localised intracellularly and stimulation of cells with insulin induced translocation to the plasma membrane. Furthermore, co-immunoprecipitation experiments in C2C12 cells showed that TERT was constitutively associated with glucose transporters (GLUTs) 1, 4 and 12 via an insulin insensitive interaction that also did not require intact PI3-K and mTOR pathways. Collectively, these findings identified a novel extra-nuclear function of TERT that regulates an insulin-insensitive pathway involved in glucose uptake in human and mouse skeletal muscle cells.


Assuntos
Núcleo Celular/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Telomerase/metabolismo , Animais , Western Blotting , Membrana Celular/metabolismo , Proliferação de Células , Células Cultivadas , Imunofluorescência , Humanos , Hipoglicemiantes/farmacologia , Técnicas Imunoenzimáticas , Imunoprecipitação , Insulina/farmacologia , Masculino , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , RNA Interferente Pequeno/genética , Telomerase/antagonistas & inibidores , Telomerase/genética
7.
Trends Biochem Sci ; 34(9): 443-52, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19733082

RESUMO

The family of G-protein coupled receptors (GPCRs) is one of the largest protein families in the mammalian genome with a fundamental role in cell biology. GPCR activity is finely tuned by various transcriptional, post-transcriptional and post-translational mechanisms. Alternative pre-mRNA splicing is now emerging as a crucial process regulating GPCR biological function. Intriguingly, this mechanism appears to extensively target the Secretin family of GPCRs, especially the exon that encodes a 14 amino acid sequence that forms the distal part of 7th transmembrane helix, and exhibits an unusually high level of sequence conservation among most Secretin GPCRs. Do the "TMD7-short" receptor variants have a role as novel regulators of GPCR signallng and, if so, what are the implications for hormonal actions and physiology?


Assuntos
Processamento Alternativo , Receptores Acoplados a Proteínas G/genética , Receptores dos Hormônios Gastrointestinais/genética , Sequência de Aminoácidos , Animais , Sequência Conservada , Éxons , Humanos , Modelos Moleculares , Filogenia , Isoformas de Proteínas , Estrutura Terciária de Proteína , Sítios de Splice de RNA , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/fisiologia , Receptores dos Hormônios Gastrointestinais/química , Receptores dos Hormônios Gastrointestinais/fisiologia , Secretina/fisiologia , Alinhamento de Sequência , Transdução de Sinais
8.
J Biol Chem ; 287(12): 8974-85, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22247544

RESUMO

The type 1 corticotropin-releasing hormone receptor (CRH-R1) influences biological responses important for adaptation to stressful stimuli, through activation of multiple downstream effectors. The structural motifs within CRH-R1 that mediate G protein activation and signaling selectivity are unknown. The aim of this study was to gain insights about important structural determinants within the third intracellular loop (IC3) of the human CRH-R1α important for cAMP and ERK1/2 pathways activation and selectivity. We investigated the role of the juxtamembrane regions of IC3 by mutating amino acid cassettes or specific residues to alanine. Although simultaneous tandem alanine mutations of both juxtamembrane regions Arg(292)-Met(295) and Lys(311)-Lys(314) reduced ligand binding and impaired signaling, all other mutant receptors retained high affinity binding, indistinguishable from wild-type receptor. Agonist-activated receptors with tandem mutations at the proximal or distal terminal segments enhanced activation of adenylyl cyclase by 50-75% and diminished activation of inositol trisphosphate and ERK1/2 by 60-80%. Single Ala mutations identified Arg(292), Lys(297), Arg(310), Lys(311), and Lys(314) as important residues for the enhanced activation of adenylyl cyclase, partly due to reduced inhibition of adenylyl cyclase activity by pertussis toxin-sensitive G proteins. In contrast, mutation of Arg(299) reduced receptor signaling activity and cAMP response. Basic as well as aliphatic amino acids within both juxtamembrane regions were identified as important for ERK1/2 phosphorylation through activation of pertussis toxin-sensitive G proteins as well as G(q) proteins. These data uncovered unexpected roles for key amino acids within the highly conserved hydrophobic N- and C-terminal microdomains of IC3 in the coordination of CRH-R1 signaling activity.


Assuntos
Receptores de Hormônio Liberador da Corticotropina/química , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Sequência de Aminoácidos , Linhagem Celular , AMP Cíclico/metabolismo , Ativação Enzimática , Humanos , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Dados de Sequência Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Receptores de Hormônio Liberador da Corticotropina/genética , Alinhamento de Sequência
9.
Cureus ; 15(9): e46181, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37905272

RESUMO

Background Pre-eclampsia remains a leading cause of maternal and foetal mortality with a poorly understood pathophysiology. It can lead to a range of clinical presentations, but proteinuria and hypertension are key components of the diagnosis. These signs arise due to disordered placental implantation due to poor trophoblastic invasion, resulting in placental oxidative stress due to hypoxia. Oxidative stress triggers the release of syncytiotrophoblast microvesicles (STMBs), of which placenta-derived exosomes may be a key component. The high specificity of exosomes for their cell of origin makes them ideal candidates as diagnostic biomarkers. We are particularly interested in the miRNAs (microRNAs) contained within these exosomes, as they may give us an insight into the genomic regulation within the pre-eclamptic placenta that leads to the disease state. The development of workflows for miRNA quantitation may enable us to identify novel biomarkers. Methods We extracted exosomes and purified total RNA from 23 serum samples using the Norgen Plasma/Serum Exosome Purification and RNA Isolation Midi Kit. We then used the bioanalyser to determine the concentration and quality of the RNA obtained. It uses rapid electrophoresis, requires minimal sample sizes, and can assess the quality of genetic material as small as 25 bases. Results We have successfully isolated RNA from these samples; however, the concentration of the total RNA was too low for downstream molecular analysis. We did gain insight into how to optimise and develop the workflow so that, with each attempt, the yield increased. Our greatest concentrations were obtained by combining serum samples from multiple patients, demonstrating that we needed a higher volume to optimise the yield. Future studies should aim to obtain samples specifically for use in this research so that we can process a larger volume of serum. Conclusions We have also noted that there is a positive correlation between the overall concentration of total RNA and a high sFlt-1/PlGF ratio. Preliminary analysis from Illumina identified with a high degree of confidence the presence of three miRNAs, namely, mir-498(46), mir-122(1), and mir-134(41). Further work is necessary to validate these findings and should focus on the possible future role of these miRNAs as biomarkers for the early diagnosis of pre-eclampsia.

10.
Front Endocrinol (Lausanne) ; 14: 1266081, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900150

RESUMO

The hypothalamic type 2 corticotropin releasing hormone receptor (CRH-R2) plays critical roles in homeostatic regulation, particularly in fine tuning stress recovery. During acute stress, the CRH-R2 ligands CRH and urocortins promote adaptive responses and feeding inhibition. However, in rodent models of chronic stress, over-exposure of hypothalamic CRH-R2 to its cognate agonists is associated with urocortin 2 (Ucn2) resistance; attenuated cAMP-response element binding protein (CREB) phosphorylation and increased food intake. The molecular mechanisms involved in these altered CRH-R2 signalling responses are not well described. In the present study, we used the adult mouse hypothalamus-derived cell line mHypoA-2/30 to investigate CRH-R2 signalling characteristics focusing on gene expression of molecules involved in feeding and circadian regulation given the role of clock genes in metabolic control. We identified functional CRH-R2 receptors expressed in mHypoA-2/30 cells that differentially regulate CREB and AMP-activated protein kinase (AMPK) phosphorylation and downstream expression of the appetite-regulatory genes proopiomelanocortin (Pomc) and neuropeptide Y (Npy) in accordance with an anorexigenic effect. We studied for the first time the effects of Ucn2 on clock genes in native and in a circadian bioluminescence reporter expressing mHypoA-2/30 cells, detecting enhancing effects of Ucn2 on mRNA levels and rhythm amplitude of the circadian regulator Aryl hydrocarbon receptor nuclear translocator-like protein 1 (Bmal1), which could facilitate anorexic responses in the activity circadian phase. These data uncover novel aspects of CRH-R2 hypothalamic signalling that might be important in regulation of circadian feeding during stress responses.


Assuntos
Hormônio Liberador da Corticotropina , Receptores de Hormônio Liberador da Corticotropina , Camundongos , Animais , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Hipotálamo/metabolismo , Urocortinas/genética , Urocortinas/metabolismo , Expressão Gênica , Neurônios/metabolismo
11.
Biochim Biophys Acta ; 1813(5): 896-907, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21338628

RESUMO

In most target tissues, the adenylyl cyclase/cAMP/PKA, the extracellular signal regulated kinase and the protein kinase B/Akt are the main pathways employed by the type 2 corticotropin-releasing hormone receptor to mediate the biological actions of urocortins (Ucns) and CRH. To decipher the molecular determinants of CRH-R2 signaling, we studied the signaling pathways in HEK293 cells overexpressing recombinant human CRH-R2ß receptors. Use of specific kinase inhibitors showed that the CRH-R2ß cognate agonist, Ucn 2, activated extracellular signal regulated kinase in a phosphoinositide 3-kinase and cyclic adenosine monophosphate/PKA-dependent manner with contribution from Epac activation. Ucn 2 also induced PKA-dependent association between AKAP250 and CRH-R2ß that appeared to be necessary for extracellular signal regulated kinase activation. PKB/Akt activation was also mediated via pertussis toxin-sensitive G-proteins and PI3-K activation but did not require cAMP/PKA, Epac or protein kinase C for optimal activation. Potential feedback mechanisms that target the CRH-R2ß itself and modulate receptor trafficking and endocytosis were also investigated. Indeed, our results suggested that inhibition of either PKA or extracellular signal regulated kinase pathway accelerates CRH-R2ß endocytosis. Furthermore, Ucn 2-activated extracellular signal regulated kinase appeared to target ß-arrestin1 and modulate, through phosphorylation at Ser412, ß-arrestin1 translocation to the plasma membrane and CRH-R2ß internalization kinetics. Loss of this "negative feedback" mechanism through inhibition of the extracellular signal regulated kinase activity resulted in significant attenuation of Ucn 2-induced cAMP response, whereas Akt phosphorylation was not affected by altered receptor endocytosis. These findings reveal a complex interplay between the signaling molecules that allow "fine-tuning" of CRH-R2ß functional responses and regulate signal integration. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.


Assuntos
Retroalimentação Fisiológica , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Transdução de Sinais , Proteínas de Ancoragem à Quinase A/metabolismo , Arrestinas/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cromonas/farmacologia , AMP Cíclico/biossíntese , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Endocitose/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Células HEK293 , Humanos , Modelos Biológicos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Urocortinas/farmacologia , beta-Arrestinas
12.
eNeuro ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35545425

RESUMO

Among the modulatory functions of thyrotropin-releasing hormone (TRH), an anorectic behavior in rodents is observed when centrally injected. Hypothalamic PVN neurons receive serotonergic inputs from dorsal raphe nucleus and express serotonin (5HT) receptors such as 5HT1A, 5HT2A/2C, 5HT6, which are involved in 5HT-induced feeding regulation. Rats subjected to dehydration-induced anorexia (DIA) model show increased PVN TRH mRNA expression, associated with their decreased food intake. We analyzed whether 5HT input is implicated in the enhanced PVN TRH transcription that anorectic rats exhibit, given that 5HT increases TRH expression and release when studied in vitro By using mHypoA-2/30 hypothalamic cell cultures, we found that 5HT stimulated TRH mRNA, pCREB and pERK1/2 levels. By inhibiting basal PKA or PKC activities or those induced by 5HT, pCREB or pERK1/2 content did not increase suggesting involvement of both kinases in their phosphorylation. 5HT effect on TRH mRNA was not affected by PKA inhibition, but it diminished in the presence of PKCi suggesting involvement of PKC in 5HT-induced TRH increased transcription. This likely involves 5HT2A/2C and the activation of alternative transduction pathways than those studied here. In agreement with the in vitro data, we found that injecting 5HT2A/2C antagonists into the PVN of DIA rats reversed the increased TRH expression of anorectic animals, as well as their decreased food intake; also, the agonist reduced food intake of hungry restricted animals along with elevated PVN TRH mRNA levels. Our results support that the anorectic effects of serotonin are mediated by PVN TRH in this model.Significance statementInteraction between brain peptides and neurotransmitters' pathways regulates feeding behavior, but when altered it could lead to the development of eating disorders, such as anorexia. An abnormal increased TRH expression in hypothalamic PVN results in dehydration-induced anorectic rats, associated to their low food intake. The role of neurotransmitters in that alteration is unknown, and since serotonin inhibits feeding and has receptors in PVN, we analyzed its participation in increasing TRH expression and reducing feeding in anorectic rats. By antagonizing PVN serotonin receptors in anorectic rats, we identify decreased TRH expression and increased feeding, suggesting that the anorectic effects of serotonin are mediated by PVN TRH. Elucidating brain networks involved in feeding regulation would help to design therapies for eating disorders.

13.
ACS Macro Lett ; 11(3): 317-322, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35575357

RESUMO

The COVID-19 pandemic has highlighted the need for innovative biosensing, diagnostic, and surveillance platforms. Here we report that glycosylated, polymer-stabilized, gold nanorods can bind the SARS-CoV-2 spike protein and show correlation to the presence of SARS-CoV-2 in primary COVID-19 clinical samples. Telechelic polymers were prepared by reversible addition-fragmentation chain-transfer polymerization, enabling the capture of 2,3-sialyllactose and immobilization onto gold nanorods. Control experiments with a panel of lectins and a galactosamine-terminated polymer confirmed the selective binding. The glycosylated rods were shown to give dose-dependent responses against recombinant truncated SARS-CoV-2 spike protein, and the responses were further correlated using primary patient swab samples. The essentiality of the anisotropic particles for reducing the background interference is demonstrated. This highlights the utility of polymer tethering of glycans for plasmonic biosensors of infection.


Assuntos
COVID-19 , Nanotubos , COVID-19/diagnóstico , Ouro , Humanos , Pandemias , Polímeros , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo
14.
Front Endocrinol (Lausanne) ; 12: 714214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408727

RESUMO

Early life is a period of considerable plasticity and vulnerability and insults during that period can disrupt the homeostatic equilibrium of the developing organism, resulting in adverse developmental programming and enhanced susceptibility to disease. Fetal exposure to prenatal stress can impede optimum brain development and deranged mother's hypothalamic-pituitary-adrenal axis (HPA axis) stress responses can alter the neurodevelopmental trajectories of the offspring. Corticotropin-releasing hormone (CRH) and glucocorticoids, regulate fetal neurogenesis and while CRH exerts neuroprotective actions, increased levels of stress hormones have been associated with fetal brain structural alterations such as reduced cortical volume, impoverishment of neuronal density in the limbic brain areas and alterations in neuronal circuitry, synaptic plasticity, neurotransmission and G-protein coupled receptor (GPCR) signalling. Emerging evidence highlight the role of epigenetic changes in fetal brain programming, as stress-induced methylation of genes encoding molecules that are implicated in HPA axis and major neurodevelopmental processes. These serve as molecular memories and have been associated with long term modifications of the offspring's stress regulatory system and increased susceptibility to psychosomatic disorders later in life. This review summarises our current understanding on the roles of CRH and other mediators of stress responses on fetal neurodevelopment.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Doenças Fetais/patologia , Transtornos do Neurodesenvolvimento/patologia , Placenta/metabolismo , Complicações na Gravidez/patologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Estresse Fisiológico , Feminino , Doenças Fetais/etiologia , Doenças Fetais/metabolismo , Humanos , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/metabolismo , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/metabolismo , Resultado da Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo
15.
Front Cell Dev Biol ; 9: 658006, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33842485

RESUMO

Coordination of cell-cell adhesion, actomyosin dynamics and gene expression is crucial for morphogenetic processes underlying tissue and organ development. Rho GTPases are main regulators of the cytoskeleton and adhesion. They are activated by guanine nucleotide exchange factors in a spatially and temporally controlled manner. However, the roles of these Rho GTPase activators during complex developmental processes are still poorly understood. ARHGEF18/p114RhoGEF is a tight junction-associated RhoA activator that forms complexes with myosin II, and regulates actomyosin contractility. Here we show that p114RhoGEF/ARHGEF18 is required for mouse syncytiotrophoblast differentiation and placenta development. In vitro and in vivo experiments identify that p114RhoGEF controls expression of AKAP12, a protein regulating protein kinase A (PKA) signaling, and is required for PKA-induced actomyosin remodeling, cAMP-responsive element binding protein (CREB)-driven gene expression of proteins required for trophoblast differentiation, and, hence, trophoblast cell-cell fusion. Our data thus indicate that p114RhoGEF links actomyosin dynamics and cell-cell junctions to PKA/CREB signaling, gene expression and cell-cell fusion.

16.
Health Technol Assess ; 25(42): 1-216, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34169821

RESUMO

BACKGROUND: Lynch syndrome is an inherited genetic condition that is associated with an increased risk of certain cancers. The National Institute for Health and Care Excellence has recommended that people with colorectal cancer are tested for Lynch syndrome. Routine testing for Lynch syndrome among people with endometrial cancer is not currently conducted. OBJECTIVES: To systematically review the evidence on the test accuracy of immunohistochemistry- and microsatellite instability-based strategies to detect Lynch syndrome among people who have endometrial cancer, and the clinical effectiveness and the cost-effectiveness of testing for Lynch syndrome among people who have been diagnosed with endometrial cancer. DATA SOURCES: Searches were conducted in the following databases, from inception to August 2019 - MEDLINE ALL, EMBASE (both via Ovid), Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (both via Wiley Online Library), Database of Abstracts of Reviews of Effects, Health Technology Assessment Database (both via the Centre for Reviews and Dissemination), Science Citation Index, Conference Proceedings Citation Index - Science (both via Web of Science), PROSPERO international prospective register of systematic reviews (via the Centre for Reviews and Dissemination), NHS Economic Evaluation Database, Cost-Effectiveness Analysis Registry, EconPapers (Research Papers in Economics) and School of Health and Related Research Health Utilities Database. The references of included studies and relevant systematic reviews were also checked and experts on the team were consulted. REVIEW METHODS: Eligible studies included people with endometrial cancer who were tested for Lynch syndrome using immunohistochemistry- and/or microsatellite instability-based testing [with or without mutL homologue 1 (MLH1) promoter hypermethylation testing], with Lynch syndrome diagnosis being established though germline testing of normal (non-tumour) tissue for constitutional mutations in mismatch repair. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool, the Consolidated Health Economic Reporting Standards and the Philips' checklist. Two reviewers independently conducted each stage of the review. A meta-analysis of test accuracy was not possible because of the number and heterogeneity of studies. A narrative summary of test accuracy results was provided, reporting test accuracy estimates and presenting forest plots. The economic model constituted a decision tree followed by Markov models for the impact of colorectal and endometrial surveillance, and aspirin prophylaxis with a lifetime time horizon. RESULTS: The clinical effectiveness search identified 3308 studies; 38 studies of test accuracy were included. (No studies of clinical effectiveness of endometrial cancer surveillance met the inclusion criteria.) Four test accuracy studies compared microsatellite instability with immunohistochemistry. No clear difference in accuracy between immunohistochemistry and microsatellite instability was observed. There was some evidence that specificity of immunohistochemistry could be improved with the addition of methylation testing. There was high concordance between immunohistochemistry and microsatellite instability. The economic model indicated that all testing strategies, compared with no testing, were cost-effective at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. Immunohistochemistry with MLH1 promoter hypermethylation testing was the most cost-effective strategy, with an incremental cost-effectiveness ratio of £9420 per quality-adjusted life-year. The second most cost-effective strategy was immunohistochemistry testing alone, but incremental analysis produced an incremental cost-effectiveness ratio exceeding £130,000. Results were robust across all scenario analyses. Incremental cost-effectiveness ratios ranged from £5690 to £20,740; only removing the benefits of colorectal cancer surveillance produced an incremental cost-effectiveness ratio in excess of the £20,000 willingness-to-pay threshold. A sensitivity analysis identified the main cost drivers of the incremental cost-effectiveness ratio as percentage of relatives accepting counselling and prevalence of Lynch syndrome in the population. A probabilistic sensitivity analysis showed, at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year, a 0.93 probability that immunohistochemistry with MLH1 promoter hypermethylation testing is cost-effective, compared with no testing. LIMITATIONS: The systematic review excluded grey literature, studies written in non-English languages and studies for which the reference standard could not be established. Studies were included when Lynch syndrome was diagnosed by genetic confirmation of constitutional variants in the four mismatch repair genes (i.e. MLH1, mutS homologue 2, mutS homologue 6 and postmeiotic segregation increased 2). Variants of uncertain significance were reported as per the studies. There were limitations in the economic model around uncertainty in the model parameters and a lack of modelling of the potential harms of gynaecological surveillance and specific pathway modelling of genetic testing for somatic mismatch repair mutations. CONCLUSION: The economic model suggests that testing women with endometrial cancer for Lynch syndrome is cost-effective, but that results should be treated with caution because of uncertain model inputs. FUTURE WORK: Randomised controlled trials could provide evidence on the effect of earlier intervention on outcomes and the balance of benefits and harms of gynaecological cancer surveillance. Follow-up of negative cases through disease registers could be used to determine false negative cases. STUDY REGISTRATION: This study is registered as PROSPERO CRD42019147185. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 42. See the NIHR Journals Library website for further project information.


Lynch syndrome is an inherited condition that is caused by a problem in the genes. People who have Lynch syndrome have a higher risk of some types of cancer (such as bowel and womb cancers) than people who do not have it. Identifying Lynch syndrome could stop cancers developing, lead to earlier treatment for cancers and help to find other family members who might have it. Currently, the National Institute for Health and Care Excellence guidance recommends testing for Lynch syndrome in people who have bowel cancer. Our aim was to investigate whether or not we should test for Lynch syndrome in women with womb cancer, and their relatives. We investigated two main tests: immunohistochemistry and microsatellite instability. There was no clear evidence that one of these tests is better than the other. There is some evidence that both tests are reasonably accurate. There was no good-quality evidence about whether or not treating women with Lynch syndrome with extra cancer screening and aspirin improves their outcomes. We used the best evidence available in our economic model, but it was at high risk of bias. The economic model suggested that testing women with endometrial cancer for Lynch syndrome is cost-effective. The best test in the model was immunohistochemistry followed by methylation testing. We are unsure of these results because of the low quality of evidence available.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose , Neoplasias do Endométrio , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Análise Custo-Benefício , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Feminino , Humanos , Anos de Vida Ajustados por Qualidade de Vida
17.
ACS Sens ; 6(10): 3696-3705, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34634204

RESUMO

The COVID-19 pandemic, and future pandemics, require diagnostic tools to track disease spread and guide the isolation of (a)symptomatic individuals. Lateral-flow diagnostics (LFDs) are rapid and of lower cost than molecular (genetic) tests, with current LFDs using antibodies as their recognition units. Herein, we develop a prototype flow-through device (related, but distinct to LFDs), utilizing N-acetyl neuraminic acid-functionalized, polymer-coated, gold nanoparticles as the detection/capture unit for SARS-COV-2, by targeting the sialic acid-binding site of the spike protein. The prototype device can give rapid results, with higher viral loads being faster than lower viral loads. The prototype's effectiveness is demonstrated using spike protein, lentiviral models, and a panel of heat-inactivated primary patient nasal swabs. The device was also shown to retain detection capability toward recombinant spike proteins from several variants (mutants) of concern. This study provides the proof of principle that glyco-lateral-flow devices could be developed to be used in the tracking monitoring of infectious agents, to complement, or as alternatives to antibody-based systems.


Assuntos
COVID-19 , Nanopartículas Metálicas , Ouro , Humanos , Pandemias , Polissacarídeos , SARS-CoV-2
18.
Endocr Rev ; 27(3): 260-86, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16484629

RESUMO

The CRH receptor (CRH-R) is a member of the secretin family of G protein-coupled receptors. Wide expression of CRH-Rs in the central nervous system and periphery ensures that their cognate agonists, the family of CRH-like peptides, are capable of exerting a wide spectrum of actions that underpin their critical role in integrating the stress response and coordinating the activity of fundamental physiological functions, such as the regulation of the cardiovascular system, energy balance, and homeostasis. Two types of mammal CRH-R exist, CRH-R1 and CRH-R2, each with unique splicing patterns and remarkably distinct pharmacological properties, but similar signaling properties, probably reflecting their distinct and sometimes contrasting biological functions. The regulation of CRH-R expression and activity is not fully elucidated, and we only now begin to fully understand the impact on mammalian pathophysiology. The focus of this review is the current and evolving understanding of the molecular mechanisms controlling CRH-R biological activity and functional flexibility. This shows notable tissue-specific characteristics, highlighted by their ability to couple to distinct G proteins and activate tissue-specific signaling cascades. The type of activating agonist, receptor, and target cell appears to play a major role in determining the overall signaling and biological responses in health and disease.


Assuntos
Hormônio Liberador da Corticotropina/fisiologia , Receptores de Hormônio Liberador da Corticotropina/fisiologia , Sequência de Aminoácidos , Animais , Hormônio Liberador da Corticotropina/genética , Humanos , Modelos Estruturais , Estrutura Terciária de Proteína , Receptores de Hormônio Liberador da Corticotropina/agonistas , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores de Hormônio Liberador da Corticotropina/química , Transdução de Sinais/fisiologia , Especificidade da Espécie
19.
Sci Rep ; 10(1): 8903, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483257

RESUMO

Bacterial neonatal meningitis results in high mortality and morbidity rates for those affected. Although improvements in diagnosis and treatment have led to a decline in mortality rates, morbidity rates have remained relatively unchanged. Bacterial resistance to antibiotics in this clinical setting further underlines the need for developing other technologies, such as phage therapy. We exploited an in vitro phage therapy model for studying bacterial neonatal meningitis based on Escherichia coli (E. coli) EV36, bacteriophage (phage) K1F and human cerebral microvascular endothelial cells (hCMECs). We show that phage K1F is phagocytosed and degraded by constitutive- and PAMP-dependent LC3-assisted phagocytosis and does not induce expression of inflammatory cytokines TNFα, IL-6, IL-8 or IFNß. Additionally, we observed that phage K1F temporarily decreases the barrier resistance of hCMEC cultures, a property that influences the barrier permeability, which could facilitate the transition of immune cells across the endothelial vessel in vivo. Collectively, we demonstrate that phage K1F can infect intracellular E. coli EV36 within hCMECs without themselves eliciting an inflammatory or defensive response. This study illustrates the potential of phage therapy targeting infections such as bacterial neonatal meningitis and is an important step for the continued development of phage therapy targeting antibiotic-resistant bacterial infections generally.


Assuntos
Bacteriófagos/fisiologia , Encéfalo/citologia , Endotélio Vascular/citologia , Escherichia coli/virologia , Encéfalo/metabolismo , Encéfalo/microbiologia , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/microbiologia , Endotélio Vascular/metabolismo , Endotélio Vascular/microbiologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/terapia , Adesões Focais/metabolismo , Humanos , Meningites Bacterianas/metabolismo , Meningites Bacterianas/terapia , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Biológicos , Terapia por Fagos , Fagocitose
20.
J Clin Med ; 9(2)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028606

RESUMO

BACKGROUND: Endocrine-disrupting chemicals (EDCs) are environmental chemicals/toxicants that humans are exposed to, interfering with the action of multiple hormones. Bisphenol A (BPA) is classified as an EDC with xenoestrogenic activity with potentially adverse effects in reproduction. Currently, a significant knowledge gap remains regarding the complete spectrum of BPA-induced effects on the human placenta. As such, the present study examined the effects of physiologically relevant doses of BPA in vitro. METHODS: qRT-PCR, Western blotting, immunofluorescence, ELISA, microarray analyses, and bioinformatics have been employed to study the effects of BPA using nonsyncytialised (non-ST) and syncytialised (ST) BeWo cells. RESULTS: Treatment with 3 nM BPA led to an increase in cell number and altered the phosphorylation status of p38, an effect mediated primarily via the membrane-bound estrogen receptor (GPR30). Nonbiased microarray analysis identified 1195 and 477 genes that were differentially regulated in non-ST BeWo cells, whereas in ST BeWo cells, 309 and 158 genes had altered expression when treated with 3 and 10 nM, respectively. Enriched pathway analyses in non-ST BeWo identified a leptin and insulin overlap (3 nM), methylation pathways (10 nM), and differentiation of white and brown adipocytes (common). In the ST model, most significantly enriched were the nuclear factor erythroid 2-related factor 2 (NRF2) pathway (3 nM) and mir-124 predicted interactions with cell cycle and differentiation (10 nM). CONCLUSION: Collectively, our data offer a new insight regarding BPA effects at the placental level, and provide a potential link with metabolic changes that can have an impact on the developing fetus.

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