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1.
Cell ; 173(3): 776-791.e17, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29576449

RESUMO

Transformation from morula to blastocyst is a defining event of preimplantation embryo development. During this transition, the embryo must establish a paracellular permeability barrier to enable expansion of the blastocyst cavity. Here, using live imaging of mouse embryos, we reveal an actin-zippering mechanism driving this embryo sealing. Preceding blastocyst stage, a cortical F-actin ring assembles at the apical pole of the embryo's outer cells. The ring structure forms when cortical actin flows encounter a network of polar microtubules that exclude F-actin. Unlike stereotypical actin rings, the actin rings of the mouse embryo are not contractile, but instead, they expand to the cell-cell junctions. Here, they couple to the junctions by recruiting and stabilizing adherens and tight junction components. Coupling of the actin rings triggers localized myosin II accumulation, and it initiates a tension-dependent zippering mechanism along the junctions that is required to seal the embryo for blastocyst formation.


Assuntos
Actinas/química , Blastocisto/metabolismo , Microtúbulos/metabolismo , Miosina Tipo II/química , Animais , Comunicação Celular , Proteínas do Citoesqueleto/química , Embrião de Mamíferos , Desenvolvimento Embrionário , Feminino , Proteínas de Fluorescência Verde , Imageamento Tridimensional , Camundongos , Camundongos Endogâmicos C57BL , Mórula , RNA Interferente Pequeno/metabolismo , Junções Íntimas
2.
Cell ; 165(1): 75-87, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27015308

RESUMO

Transcription factor (TF) binding to DNA is fundamental for gene regulation. However, it remains unknown how the dynamics of TF-DNA interactions change during cell-fate determination in vivo. Here, we use photo-activatable FCS to quantify TF-DNA binding in single cells of developing mouse embryos. In blastocysts, the TFs Oct4 and Sox2, which control pluripotency, bind DNA more stably in pluripotent than in extraembryonic cells. By contrast, in the four-cell embryo, Sox2 engages in more long-lived interactions than does Oct4. Sox2 long-lived binding varies between blastomeres and is regulated by H3R26 methylation. Live-cell tracking demonstrates that those blastomeres with more long-lived binding contribute more pluripotent progeny, and reducing H3R26 methylation decreases long-lived binding, Sox2 target expression, and pluripotent cell numbers. Therefore, Sox2-DNA binding predicts mammalian cell fate as early as the four-cell stage. More generally, we reveal the dynamic repartitioning of TFs between DNA sites driven by physiological epigenetic changes. VIDEO ABSTRACT.


Assuntos
Fatores de Transcrição SOXB1/metabolismo , Animais , Blastocisto/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , DNA/metabolismo , Difusão , Regulação para Baixo , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/análise , Histonas/metabolismo , Cinética , Metilação , Camundongos , Fator 3 de Transcrição de Octâmero/metabolismo , Espectrometria de Fluorescência
3.
J Cell Sci ; 137(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38904172

RESUMO

Collective cell migration, where cells move as a cohesive unit, is a vital process underlying morphogenesis and cancer metastasis. Thanks to recent advances in imaging and modelling, we are beginning to understand the intricate relationship between a cell and its microenvironment and how this shapes cell polarity, metabolism and modes of migration. The use of biophysical and mathematical models offers a fresh perspective on how cells migrate collectively, either flowing in a fluid-like state or transitioning to more static states. Continuing to unite researchers in biology, physics and mathematics will enable us to decode more complex biological behaviours that underly collective cell migration; only then can we understand how this coordinated movement of cells influences the formation and organisation of tissues and directs the spread of metastatic cancer. In this Perspective, we highlight exciting discoveries, emerging themes and common challenges that have arisen in recent years, and possible ways forward to bridge the gaps in our current understanding of collective cell migration.


Assuntos
Movimento Celular , Animais , Humanos , Movimento Celular/fisiologia , Polaridade Celular , Modelos Biológicos
4.
Nucleic Acids Res ; 51(11): e62, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37125641

RESUMO

Methods for cell clustering and gene expression from single-cell RNA sequencing (scRNA-seq) data are essential for biological interpretation of cell processes. Here, we present TRIAGE-Cluster which uses genome-wide epigenetic data from diverse bio-samples to identify genes demarcating cell diversity in scRNA-seq data. By integrating patterns of repressive chromatin deposited across diverse cell types with weighted density estimation, TRIAGE-Cluster determines cell type clusters in a 2D UMAP space. We then present TRIAGE-ParseR, a machine learning method which evaluates gene expression rank lists to define gene groups governing the identity and function of cell types. We demonstrate the utility of this two-step approach using atlases of in vivo and in vitro cell diversification and organogenesis. We also provide a web accessible dashboard for analysis and download of data and software. Collectively, genome-wide epigenetic repression provides a versatile strategy to define cell diversity and study gene regulation of scRNA-seq data.


Assuntos
Perfilação da Expressão Gênica , Análise de Célula Única , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Software , Análise por Conglomerados , Epigênese Genética , Algoritmos
5.
J Behav Med ; 47(2): 271-281, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37814036

RESUMO

The ubiquity of energy-dense, processed foods has been implicated as a salient feature of the modern 'obesogenic' environment. Cognitive strategies, such as response inhibition training, have been demonstrated to reduce the hedonic value of such foods in previous studies. However, this effect has generally been inconsistent or heterogenous, depending on the outcome measure, characteristics of the sample, and the specificity of food stimuli. Characterising the extent of generalised effects may help define the application of this type of intervention in natural settings. A repeated-measures, proof-of-concept study, using mobile app-based response inhibition training (RIT) versus a control app-based activity (N = 25), was undertaken to establish the valid application of a food reward measure to assess intervention efficacy. Liking (i.e., affect) and wanting (i.e., motivation) for food stimuli categorised by energy density were taken concurrently pre- and post-training. A statistically significant reduction in explicit liking, but not implicit wanting, for foods irrespective of their energy density was observed during the RIT app-based training session relative to the control (p = .041, ηp2 = .16). However, effect sizes associated with devaluation of energy-dense relative to low calorie food stimuli, although non-significant, were higher when measured as implicitly wanting (p = .098, ηp2 = .11) than explicit liking (p = .756, ηp2 = .00). Trends in explicit stimulus evaluations were empirically discordant from implicit evaluations for low calorie foods in particular. Additional research is needed to investigate whether these trends are reproducible with larger samples, trained and novel food stimuli in outcome measures, and more comprehensive training protocols.


Assuntos
Preferências Alimentares , Alimentos , Humanos , Preferências Alimentares/psicologia , Estudo de Prova de Conceito , Motivação , Recompensa
6.
Appetite ; 198: 107363, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636669

RESUMO

Over the last decade, there have been repeated calls to expand the operationalisation of food parenting practices. The conceptualisation and measurement of these practices has been based primarily on research with parent-child dyads. One unexplored dimension of food parenting pertains to the evaluation of practices specific to feeding siblings. This study describes the development and validation of the Feeding Siblings Questionnaire (FSQ) - a tool designed to measure practices in which siblings are positioned as mediators in parents' attempts to prompt or persuade a child to eat. Item development was guided by a conceptual model derived from mixed-methods research and refined through expert reviews and cognitive interviews. These interviews were conducted in two phases, where parents responded to the questionnaire primarily to test i) the readability and relevance of each item, and ii) its overall feasibility. The instrument was completed by 330 parents (96.1% mothers) in Australia with two children aged 2-5 years, and repeated by 133 parents (40.3%) two weeks later. Exploratory factor analysis was performed on baseline data. Internal consistency and test re-test reliability of the subsequent subscales were examined. Construct validity was assessed through comparisons with existing measures of food parenting practices and child eating behaviours. The final FSQ scale included 22 items, reflecting five food parenting practices: sibling competitiveness, active sibling influence, threatening unequal division of food, sibling role modelling, and vicarious operant conditioning. Internal consistency and test re-test reliability estimates were high, and there was some evidence of convergent construct validity. While its factor structure should be confirmed in a different sample, the FSQ offers a novel tool for assessing, monitoring, and evaluating feeding interactions beyond those confined to the parent-child dyad.


Assuntos
Comportamento Alimentar , Poder Familiar , Pais , Autorrelato , Irmãos , Humanos , Feminino , Masculino , Pré-Escolar , Poder Familiar/psicologia , Reprodutibilidade dos Testes , Irmãos/psicologia , Inquéritos e Questionários/normas , Comportamento Alimentar/psicologia , Pais/psicologia , Adulto , Austrália , Relações Pais-Filho , Comportamento Infantil/psicologia , Psicometria/métodos
7.
Semin Cell Dev Biol ; 120: 133-146, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34147339

RESUMO

Research using avian embryos has led to major conceptual advances in developmental biology, virology, immunology, genetics and cell biology. The avian embryo has several significant advantages, including ready availability and ease of accessibility, rapid development with marked similarities to mammals and a high amenability to manipulation. As mechanical forces are increasingly recognised as key drivers of morphogenesis, this powerful model system is shedding new light on the mechanobiology of embryonic development. Here, we highlight progress in understanding how mechanical forces direct key morphogenetic processes in the early avian embryo. Recent advances in quantitative live imaging and modelling are elaborating upon traditional work using physical models and embryo manipulations to reveal cell dynamics and tissue forces in ever greater detail. The recent application of transgenic technologies further increases the strength of the avian model and is providing important insights about previously intractable developmental processes.


Assuntos
Doenças das Aves/embriologia , Desenvolvimento Embrionário/imunologia , Animais , Gastrulação
8.
Biochem Soc Trans ; 51(1): 343-352, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36794768

RESUMO

The vertebrate brain and spinal cord arise from a common precursor, the neural tube, which forms very early during embryonic development. To shape the forming neural tube, changes in cellular architecture must be tightly co-ordinated in space and time. Live imaging of different animal models has provided valuable insights into the cellular dynamics driving neural tube formation. The most well-characterised morphogenetic processes underlying this transformation are convergent extension and apical constriction, which elongate and bend the neural plate. Recent work has focused on understanding how these two processes are spatiotemporally integrated from the tissue- to the subcellular scale. Various mechanisms of neural tube closure have also been visualised, yielding a growing understanding of how cellular movements, junctional remodelling and interactions with the extracellular matrix promote fusion and zippering of the neural tube. Additionally, live imaging has also now revealed a mechanical role for apoptosis in neural plate bending, and how cell intercalation forms the lumen of the secondary neural tube. Here, we highlight the latest research on the cellular dynamics underlying neural tube formation and provide some perspectives for the future.


Assuntos
Placa Neural , Tubo Neural , Animais , Movimento Celular , Morfogênese , Encéfalo
9.
Brain ; 145(9): 3108-3130, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35512359

RESUMO

Aberrant self-assembly and toxicity of wild-type and mutant superoxide dismutase 1 (SOD1) has been widely examined in silico, in vitro and in transgenic animal models of amyotrophic lateral sclerosis. Detailed examination of the protein in disease-affected tissues from amyotrophic lateral sclerosis patients, however, remains scarce. We used histological, biochemical and analytical techniques to profile alterations to SOD1 protein deposition, subcellular localization, maturation and post-translational modification in post-mortem spinal cord tissues from amyotrophic lateral sclerosis cases and controls. Tissues were dissected into ventral and dorsal spinal cord grey matter to assess the specificity of alterations within regions of motor neuron degeneration. We provide evidence of the mislocalization and accumulation of structurally disordered, immature SOD1 protein conformers in spinal cord motor neurons of SOD1-linked and non-SOD1-linked familial amyotrophic lateral sclerosis cases, and sporadic amyotrophic lateral sclerosis cases, compared with control motor neurons. These changes were collectively associated with instability and mismetallation of enzymatically active SOD1 dimers, as well as alterations to SOD1 post-translational modifications and molecular chaperones governing SOD1 maturation. Atypical changes to SOD1 protein were largely restricted to regions of neurodegeneration in amyotrophic lateral sclerosis cases, and clearly differentiated all forms of amyotrophic lateral sclerosis from controls. Substantial heterogeneity in the presence of these changes was also observed between amyotrophic lateral sclerosis cases. Our data demonstrate that varying forms of SOD1 proteinopathy are a common feature of all forms of amyotrophic lateral sclerosis, and support the presence of one or more convergent biochemical pathways leading to SOD1 proteinopathy in amyotrophic lateral sclerosis. Most of these alterations are specific to regions of neurodegeneration, and may therefore constitute valid targets for therapeutic development.


Assuntos
Esclerose Lateral Amiotrófica , Processamento de Proteína Pós-Traducional , Superóxido Dismutase-1 , Esclerose Lateral Amiotrófica/genética , Humanos , Mutação , Medula Espinal/patologia , Superóxido Dismutase-1/genética
10.
Matern Child Nutr ; 19(2): e13484, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36808876

RESUMO

Obesity prevention interventions have been designed to promote responsive feeding in early childhood. However, existing interventions primarily target first-time mothers without considering the complexities of feeding multiple children within a family unit. By applying principles of Constructivist Grounded Theory (CGT), this study aimed to explore how mealtimes are enacted in families with more than one child. A mixed-methods study was conducted with parent-sibling triads (n = 18 families) in South East Queensland, Australia. Data included direct mealtime observations, semistructured interviews, field notes, and memos. Data were analysed using open and focused coding, during which constant comparative analysis was applied. The sample comprised of two-parent families with children ranging in age from 12 to 70 months (median sibling age difference = 24 months). A conceptual model was developed to map sibling-related processes integral to the enactment of mealtimes in families. Notably, this model captured feeding practices used by siblings, such as pressure to eat and overt restriction, that previously had only been described in parents. It also documented feeding practices used by parents that may occur only in the presence of a sibling, such as leveraging sibling competitiveness and rewarding a child to vicariously condition their sibling's behaviour. The conceptual model demonstrates complexities in feeding that give shape to the overall family food environment. Findings from this study can inform the design of early feeding interventions that support parents to remain responsive, particularly when their perceptions and expectations of siblings differ.


Assuntos
Comportamento Alimentar , Irmãos , Criança , Feminino , Humanos , Pré-Escolar , Lactente , Teoria Fundamentada , Austrália , Pais , Refeições
11.
J Mol Cell Cardiol ; 164: 92-109, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34826416

RESUMO

The incidence of type 2 diabetes (T2D) is increasing globally, with long-term implications for human health and longevity. Heart disease is the leading cause of death in T2D patients, who display an elevated risk of an acute cardiovascular event and worse outcomes following such an insult. The underlying mechanisms that predispose the diabetic heart to this poor prognosis remain to be defined. This study developed a pre-clinical model (Rattus norvegicus) that complemented caloric excess from a high-fat diet (HFD) and pancreatic ß-cell dysfunction from streptozotocin (STZ) to produce hyperglycaemia, peripheral insulin resistance, hyperlipidaemia and elevated fat mass to mimic the clinical features of T2D. Ex vivo cardiac function was assessed using Langendorff perfusion with systolic and diastolic contractile depression observed in T2D hearts. Cohorts representing untreated, individual HFD- or STZ-treatments and the combined HFD + STZ approach were used to generate ventricular samples (n = 9 per cohort) for sequential and integrated analysis of the proteome, lipidome and metabolome by liquid chromatography-tandem mass spectrometry. This study found that in T2D hearts, HFD treatment primed the metabolome, while STZ treatment was the major driver for changes in the proteome. Both treatments equally impacted the lipidome. Our data suggest that increases in ß-oxidation and early TCA cycle intermediates promoted rerouting via 2-oxaloacetate to glutamate, γ-aminobutyric acid and glutathione. Furthermore, we suggest that the T2D heart activates networks to redistribute excess acetyl-CoA towards ketogenesis and incomplete ß-oxidation through the formation of short-chain acylcarnitine species. Multi-omics provided a global and comprehensive molecular view of the diabetic heart, which distributes substrates and products from excess ß-oxidation, reduces metabolic flexibility and impairs capacity to restore high energy reservoirs needed to respond to and prevent subsequent acute cardiovascular events.


Assuntos
Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Ácidos Graxos/metabolismo , Humanos , Insulina , Proteoma , Ratos
12.
Circulation ; 144(12): 947-960, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34264749

RESUMO

BACKGROUND: Ischemia-reperfusion injury (IRI) is one of the major risk factors implicated in morbidity and mortality associated with cardiovascular disease. During cardiac ischemia, the buildup of acidic metabolites results in decreased intracellular and extracellular pH, which can reach as low as 6.0 to 6.5. The resulting tissue acidosis exacerbates ischemic injury and significantly affects cardiac function. METHODS: We used genetic and pharmacologic methods to investigate the role of acid-sensing ion channel 1a (ASIC1a) in cardiac IRI at the cellular and whole-organ level. Human induced pluripotent stem cell-derived cardiomyocytes as well as ex vivo and in vivo models of IRI were used to test the efficacy of ASIC1a inhibitors as pre- and postconditioning therapeutic agents. RESULTS: Analysis of human complex trait genetics indicates that variants in the ASIC1 genetic locus are significantly associated with cardiac and cerebrovascular ischemic injuries. Using human induced pluripotent stem cell-derived cardiomyocytes in vitro and murine ex vivo heart models, we demonstrate that genetic ablation of ASIC1a improves cardiomyocyte viability after acute IRI. Therapeutic blockade of ASIC1a using specific and potent pharmacologic inhibitors recapitulates this cardioprotective effect. We used an in vivo model of myocardial infarction and 2 models of ex vivo donor heart procurement and storage as clinical models to show that ASIC1a inhibition improves post-IRI cardiac viability. Use of ASIC1a inhibitors as preconditioning or postconditioning agents provided equivalent cardioprotection to benchmark drugs, including the sodium-hydrogen exchange inhibitor zoniporide. At the cellular and whole organ level, we show that acute exposure to ASIC1a inhibitors has no effect on cardiac ion channels regulating baseline electromechanical coupling and physiologic performance. CONCLUSIONS: Our data provide compelling evidence for a novel pharmacologic strategy involving ASIC1a blockade as a cardioprotective therapy to improve the viability of hearts subjected to IRI.


Assuntos
Canais Iônicos Sensíveis a Ácido/biossíntese , Canais Iônicos Sensíveis a Ácido/genética , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Animais , Células Cultivadas , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Preparação de Coração Isolado/métodos , Masculino , Camundongos , Camundongos Knockout , Isquemia Miocárdica/terapia , Traumatismo por Reperfusão Miocárdica/terapia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Polimorfismo de Nucleotídeo Único/fisiologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Venenos de Aranha/farmacologia
13.
Appetite ; 178: 106181, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35870536

RESUMO

Previous studies have demonstrated that response inhibition training can modify the appeal of palatable and energy-dense foods, thus serving as a potential intervention for weight management, via changes in food selection and intake. However, empirical findings of efficacy have been inconsistent across studies due to heterogenous approaches to measuring salient appetitive outcomes, training implementation strategies, and sample recruitment. Systematic assessment of both affective and motivational components of food reward may help characterise to what extent devaluation can be generalised to nutritionally similar foods post-training. In this mixed factorial experiment, a non-clinical, adult sample completed time-matched single sessions with mobile app-based response inhibition training and control tasks of short (12 min; n = 27) or long (20 min; n = 25) duration. Participants were assessed on two discrete facets of food reward pre- and post-training: pleasure (i.e., explicit liking) and desire (i.e., implicit wanting) for non-specific (i.e., novel) food stimuli differing in energy-density. Consumption of snacks categorised by energy density was also assessed in a laboratory ad libitum taste test post-training. No significant differences were found between intervention and control sessions on explicit liking or implicit wanting for non-specific energy-dense foods. Moreover, participants ate a similar volume of snack foods during both sessions. Training duration did not significantly moderate differences between intervention and control sessions in primary outcomes. Variance between intervention and control sessions in chocolate intake and frequency of choice for energy-dense foods, but not explicit liking, was associated with a higher BMI. Methodological and theoretical implications for appropriate intervention implementation and underlying mechanisms, respectively, are discussed.


Assuntos
Aplicativos Móveis , Adulto , Preferências Alimentares/psicologia , Humanos , Recompensa , Lanches/psicologia , Paladar
14.
J Hepatol ; 74(1): 80-88, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679299

RESUMO

BACKGROUND & AIMS: Altered microbiota can affect the gut-liver-brain axis in cirrhosis and hepatic encephalopathy (HE), but the impact of sex on these changes is unclear. We aimed to determine differences in fecal microbiota composition/functionality between men and women with cirrhosis and HE on differing treatments. METHODS: Cross-sectional stool microbiome composition (16s rRNA sequencing) and microbial functional analyses were performed in men and women with cirrhosis, and controls. Patients with HE on rifaximin+lactulose (HE-Rif), patients with HE on lactulose only (HE-Lac) and those with cirrhosis without HE (No-HE) were compared to controls using random forest classifier. Men and women were also compared. RESULTS: A total of 761 individuals were included, 619 with cirrhosis (466 men, 153 women) and 142 controls (92 men, 50 women). Men were older and more frequently used proton pump inhibitors (PPIs), but model for end-stage liver disease score, No-HE (n = 319), HE-lac (n = 130) and HE-Rif (n = 170) proportions were similar. PPI/age-adjusted AUC of differentiation between controls vs. all cirrhosis, and controls vs. No-HE were higher within women than men, but the adjusted AUC for No-HE vs. HE-Rif was higher in men. Control vs. HE-Rif differentiation was similar across sexes. Men vs. women were different in all cirrhosis, No-HE and HE-Lac but not HE-Rif on PERMANOVA and AUC analyses. Autochthonous taxa decreased and pathobionts increased with disease progression regardless of sex. In men, Lactobacillaceae were higher in HE-Lac but decreased in HE-Rif, along with Veillonellaceae. Pathways related to glutamate and aromatic compound degradation were higher in men at all stages. Degradation of androstenedione, an estrogenic precursor, was lower in men vs. women in HE-Rif, likely enhancing feminization. CONCLUSIONS: There are differences in gut microbial function and composition between men and women with cirrhosis, which could be implicated in differential responses to HE therapies. Further studies linking these differences to sex-specific outcomes are needed. LAY SUMMARY: Patients with cirrhosis develop changes in their brain function, and men often develop feminization with disease progression. However, the interaction between sex, microbiota and disease severity is unclear. We found that as disease progressed in men, their microbial composition began to approach that observed in women, with changes in specific microbes that are associated with male hormone metabolism.


Assuntos
Doença Hepática Terminal , Microbioma Gastrointestinal , Encefalopatia Hepática , Lactulose/uso terapêutico , Cirrose Hepática/complicações , Rifaximina/uso terapêutico , Eixo Encéfalo-Intestino , Correlação de Dados , Estudos Transversais , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/etiologia , Feminino , Fármacos Gastrointestinais/uso terapêutico , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/análise , Análise de Sequência de RNA/métodos , Fatores Sexuais
15.
Gastroenterology ; 159(5): 1715-1730.e12, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32687928

RESUMO

BACKGROUND & AIMS: Inpatients with cirrhosis have high rates of acute-on-chronic failure (ACLF) development and high mortality within 30 days of admission to the hospital. Better biomarkers are needed to predict these outcomes. We performed metabolomic analyses of serum samples from patients with cirrhosis at multiple centers to determine whether metabolite profiles might identify patients at high risk for ACLF and death. METHODS: We performed metabolomic analyses, using liquid chromatography, of serum samples collected at time of admission to 12 North American tertiary hepatology centers from 602 patients in the North American Consortium for the Study of End-Stage Liver Disease sites from 2015 through 2017 (mean age, 56 years; 61% men; mean model for end-stage liver disease score, 19.5). We performed analysis of covariance, adjusted for model for end-stage liver disease at time of hospital admission, serum levels of albumin and sodium, and white blood cell count, to identify metabolites that differed between patients who did vs did not develop ACLF and patients who did vs did not die during hospitalization and within 30 days. We performed random forest analysis to identify specific metabolite(s) that were associated with outcomes and area under the curve (AUC) analyses to analyze them in context of clinical parameters. We analyzed microbiomes of stool samples collected from 133 patients collected at the same time and examined associations with serum metabolites. RESULTS: Of the 602 patients analyzed, 88 developed ACLF (15%), 43 died in the hospital (7%), and 72 died within 30 days (12%). Increased levels of compounds of microbial origin (aromatic compounds, secondary or sulfated bile acids, and benzoate) and estrogen metabolites, as well as decreased levels of phospholipids, were associated with development of ACLF, inpatient, and 30-day mortality and were also associated with fecal microbiomes. Random forest analysis and logistic regression showed that levels of specific microbially produced metabolites identified patients who developed ACLF with an AUC of 0.84 (95% confidence interval [CI] 0.78-0.88; P = .001), patients who died while in the hospital with an AUC of 0.81 (95% CI 0.74-0.85; P = .002), and patients who died within 30 days with an AUC of 0.77 (95% CI 0.73-0.81; P = .02). The metabolites were significantly additive to clinical parameters for predicting these outcomes. Metabolites associated with outcomes were also correlated with microbiomes of stool samples. CONCLUSIONS: In an analysis of serum metabolites and fecal microbiomes of patients hospitalized with cirrhosis at multiple centers, we associated metabolites of microbial origin and lipid moieties with development of ACLF and death as an inpatient or within 30 days, after controlling for clinical features.


Assuntos
Insuficiência Hepática Crônica Agudizada/sangue , Bactérias/metabolismo , Microbioma Gastrointestinal , Lipídeos/sangue , Cirrose Hepática/sangue , Metabolômica , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/microbiologia , Insuficiência Hepática Crônica Agudizada/mortalidade , Adulto , Idoso , Biomarcadores/sangue , Bases de Dados Factuais , Fezes/microbiologia , Feminino , Mortalidade Hospitalar , Humanos , Lipidômica , Cirrose Hepática/diagnóstico , Cirrose Hepática/microbiologia , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , América do Norte , Admissão do Paciente , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
16.
J Neuroinflammation ; 18(1): 237, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34656141

RESUMO

BACKGROUND: Type I interferons (IFN-I) are key responders to central nervous system infection and injury and are also increased in common neurodegenerative diseases. Their effects are primarily mediated via transcriptional regulation of several hundred interferon-regulated genes. In addition, IFN-I activate several kinases including members of the MAPK and PI3K families. Yet, how changes to the global protein phosphoproteome contribute to the cellular response to IFN-I is unknown. METHODS: The cerebral phosphoproteome of mice with brain-targeted chronic production of the IFN-I, IFN-α, was obtained. Changes in phosphorylation were analyzed by ontology and pathway analysis and kinase enrichment predictions. These were verified by phenotypic analysis, immunohistochemistry and immunoblots. In addition, primary murine microglia and astrocytes, the brain's primary IFN-I-responding cells, were acutely treated with IFN-α and the global phosphoproteome was similarly analyzed. RESULTS: We identified widespread protein phosphorylation as a novel mechanism by which IFN-I mediate their effects. In our mouse model for IFN-I-induced neurodegeneration, protein phosphorylation, rather than the proteome, aligned with the clinical hallmarks and pathological outcome, including impaired development, motor dysfunction and seizures. In vitro experiments revealed extensive and rapid IFN-I-induced protein phosphorylation in microglia and astrocytes. Response to acute IFN-I stimulation was independent of gene expression and mediated by a small number of kinase families. The changes in the phosphoproteome affected a diverse range of cellular processes and functional analysis suggested that this response induced an immediate reactive state and prepared cells for subsequent transcriptional responses. CONCLUSIONS: Our studies reveal a hitherto unappreciated role for changes in the protein phosphorylation landscape in cellular responses to IFN-I and thus provide insights for novel diagnostic and therapeutic strategies for neurological diseases caused by IFN-I.


Assuntos
Encéfalo/metabolismo , Interferon Tipo I/farmacologia , Microglia/metabolismo , Fosfopeptídeos/metabolismo , Proteômica/métodos , Animais , Encéfalo/efeitos dos fármacos , Células Cultivadas , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/efeitos dos fármacos , Fosfopeptídeos/genética , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia
17.
Dig Dis Sci ; 66(4): 1360-1366, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32323075

RESUMO

BACKGROUND: Cirrhosis is associated with poor health-related quality of life (HRQOL), cognitive dysfunction (CD), and lack of coordination leading to falls. Tandem gait (TG; heel-toe) can be used to assess coordination. The impact and relationship between CD, TG and falls pre-/post-liver transplant (LT) is unclear. We aimed to determine the impact of LT on CD, abnormal TG, and HRQOL in cirrhosis. METHODS: We analyzed patients who underwent complete neurological examination, cognitive testing by psychometric hepatic encephalopathy score (PHES), and HRQOL assessment using sickness impact profile (SIP). All patients were followed for 1 post-LT visit at 6 or 12 months post-LT for clinical course and falls. Change in CD, TD, and falls pre-/post-LT were compared. RESULTS: Off 131 recruited, 61 patients completed all visits. Majority were men (84%), with HCV etiology (34%). Pre-LT: Abnormal TG trended towards increased falls (OR 3.3, P = 0.08). Forty-nine % had abnormal TG, 61% had CD, 32.7% had CD + abnormal TG, 62% had prior OHE, and 14.7% had falls. Abnormal and normal TG patients had similar ages, BMI, sex, education level, and MELD scores. Abnormal TG group had higher prior overt HE (P = 0.03) and worse physical SIP score (P = 0.008). Post-LT: There was sustained improvement in CD, HRQOL, falls, and TG post-LT more at 12 than 6 months in all patients. Patients who had abnormal TG pre-LT continued to have a worse PHES (P = 0.0064) and physical SIP score (P = 0.008) compared to normal pre-LT TG patients. CONCLUSION: After LT, there is a sustained improvement in coordination measured via tandem gait, accompanied by a lower rate of falls.


Assuntos
Acidentes por Quedas/prevenção & controle , Análise da Marcha/métodos , Marcha/fisiologia , Cirrose Hepática/cirurgia , Transplante de Fígado/tendências , Qualidade de Vida , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Disfunção Cognitiva/cirurgia , Feminino , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/psicologia , Transplante de Fígado/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida/psicologia , Fatores de Risco , Resultado do Tratamento
18.
Mol Cell Proteomics ; 18(4): 715-734, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30617158

RESUMO

Campylobacter jejuni is a major gastrointestinal pathogen generally acquired via consumption of poorly prepared poultry. N-linked protein glycosylation encoded by the pgl gene cluster targets >80 membrane proteins and is required for both nonsymptomatic chicken colonization and full human virulence. Despite this, the biological functions of N-glycosylation remain unknown. We examined the effects of pgl gene deletion on the C. jejuni proteome using label-based liquid chromatography/tandem mass spectrometry (LC-MS/MS) and validation using data independent acquisition (DIA-SWATH-MS). We quantified 1359 proteins corresponding to ∼84% of the C. jejuni NCTC 11168 genome, and 1080 of these were validated by DIA-SWATH-MS. Deletion of the pglB oligosaccharyltransferase (ΔpglB) resulted in a significant change in abundance of 185 proteins, 137 of which were restored to their wild-type levels by reintroduction of pglB (Δaaz.batpglB::ΔpglB). Deletion of pglB was associated with significantly reduced abundances of pgl targets and increased stress-related proteins, including ClpB, GroEL, GroES, GrpE and DnaK. pglB mutants demonstrated reduced survival following temperature (4 °C and 46 °C) and osmotic (150 mm NaCl) shock and altered biofilm phenotypes compared with wild-type C. jejuni Targeted metabolomics established that pgl negative C. jejuni switched from aspartate (Asp) to proline (Pro) uptake and accumulated intracellular succinate related to proteome changes including elevated PutP/PutA (proline transport and utilization), and reduced DctA/DcuB (aspartate import and succinate export, respectively). ΔpglB chemotaxis to some substrates (Asp, glutamate, succinate and α-ketoglutarate) was reduced and associated with altered abundance of transducer-like (Tlp) proteins. Glycosylation negative C. jejuni were depleted of all respiration-associated proteins that allow the use of alternative electron acceptors under low oxygen. We demonstrate for the first time that N-glycosylation is required for a specific enzyme activity (Nap nitrate reductase) that is associated with reduced abundance of the NapAB glycoproteins. These data indicate a multifactorial role for N-glycosylation in C. jejuni physiology.


Assuntos
Proteínas de Bactérias/metabolismo , Campylobacter jejuni/metabolismo , Proteômica , Transporte Biológico , Células CACO-2 , Transporte de Elétrons , Glicoproteínas/metabolismo , Glicosilação , Humanos , Mutação/genética , Nitrato Redutase/metabolismo , Fenótipo
19.
J Med Internet Res ; 23(4): e24639, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33744844

RESUMO

BACKGROUND: Health information technology (IT) interventions to decrease readmissions for cirrhosis may be limited by patient-associated factors. OBJECTIVE: The aim of this study was to determine perspectives regarding adoption versus refusal of health IT interventions among patient-caregiver dyads. METHODS: Inpatients with cirrhosis and their caregivers were approached to participate in a randomized health IT intervention trial requiring daily contact with research teams via the Patient Buddy app. This app focuses on ascites, medications, and hepatic encephalopathy over 30 days. Regression analyses for characteristics associated with acceptance were performed. For those who declined, a semistructured interview was performed with themes focused on caregivers, protocol, transport/logistics, technology demands, and privacy. RESULTS: A total of 349 patient-caregiver dyads were approached (191 from Virginia Commonwealth University, 56 from Richmond Veterans Affairs Medical Center, and 102 from Mayo Clinic), 87 of which (25%) agreed to participate. On regression, dyads agreeing included a male patient (odds ratio [OR] 2.08, P=.01), gastrointestinal bleeding (OR 2.3, P=.006), or hepatic encephalopathy admission (OR 2.0, P=.01), whereas opioid use (OR 0.46, P=.03) and alcohol-related etiology (OR 0.54, P=.02) were associated with refusal. Race, study site, and other admission reasons did not contribute to refusing participation. Among the 262 dyads who declined randomization, caregiver reluctance (43%), perceived burden (31%), technology-related issues (14%), transportation/logistics (10%), and others (4%), but not privacy, were highlighted as major concerns. CONCLUSIONS: Patients with cirrhosis admitted with hepatic encephalopathy and gastrointestinal bleeding without opioid use or alcohol-related etiologies were more likely to participate in a health IT intervention focused on preventing readmissions. Caregiver and study burden but not privacy were major reasons to decline participation. Reducing perceived patient-caregiver burden and improving communication may improve participation. TRIAL REGISTRATION: ClinicalTrials.gov NCT03564626; https://www.clinicaltrials.gov/ct2/show/NCT03564626.


Assuntos
Cuidadores , Pacientes Internados , Estudos Transversais , Humanos , Cirrose Hepática , Masculino , Qualidade de Vida
20.
Clin Gastroenterol Hepatol ; 18(13): 3008-3016.e2, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32205222

RESUMO

BACKGROUND & AIMS: Patients with cirrhosis are growing older. The overlap between minimal hepatic encephalopathy (MHE) and predementia mild cognitive impairment (MCI) could affect quality of life (QOL). We investigated the performance of elderly patients with cirrhosis on tests for MHE and MCI and their effects on QOL. METHODS: We recruited outpatients with cirrhosis (n = 109) and without cirrhosis (controls, n = 100), 65 years or older, at 4 centers (derivation cohort). All study participants were assessed for psychometric hepatic encephalopathy score (PHES), EncephalApp score, and QOL. MCI was tested in patients with cirrhosis using the repeatable battery for assessment of neuropsychological status and assigned to the following groups: unimpaired, MCI only, MHE only, and MCI+MHE. We created adjusted norms to detect MHE using PHES and EncephalApp scores from the controls. Findings were validated using data from a separate cohort of 77 patients with cirrhosis (mean age, 69.49 ± 4.36 y; 72% men) at the same study sites. RESULTS: Controls were older but were more educated, performed better cognitively, and had better QOL. Among patients with cirrhosis, age, education, model for end-stage liver disease score, EncephalApp score, and QOL were similar, but PHES and repeatable battery for assessment of neuropsychological status differed among sites. In the derivation cohort, the presence of MHE, with or without MCI, was associated with poor QOL, which was lowest in the MCI+MHE group. When we adjusted for age, sex, and education, 49% of patients with cirrhosis had MHE based on the EncephalApp and 8% had MHE based on the PHES. A similar pattern (49% MHE based on EncephalApp and 6% MHE based on PHES) was found in a validation cohort. CONCLUSIONS: In a multicenter study of patients with cirrhosis (>65 y) and controls, the presence of MHE, regardless of MCI, was associated with poor cognition and QOL. We created adjusted norms that defined the high sensitivity of EncephalApp for the detection of MHE in older individuals and validated it in a separate cohort.


Assuntos
Disfunção Cognitiva , Doença Hepática Terminal , Encefalopatia Hepática , Idoso , Feminino , Encefalopatia Hepática/epidemiologia , Humanos , Cirrose Hepática/complicações , Masculino , Psicometria , Qualidade de Vida , Índice de Gravidade de Doença
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