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1.
Cell Rep ; 42(6): 112533, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37257449

RESUMO

The acquisition of mesenchymal traits is considered a hallmark of breast cancer progression. However, the functional relevance of epithelial-to-mesenchymal transition (EMT) remains controversial and context dependent. Here, we isolate epithelial and mesenchymal populations from human breast cancer metastatic biopsies and assess their functional potential in vivo. Strikingly, progressively decreasing epithelial cell adhesion molecule (EPCAM) levels correlate with declining disease propagation. Mechanistically, we find that persistent EPCAM expression marks epithelial clones that resist EMT induction and propagate competitively. In contrast, loss of EPCAM defines clones arrested in a mesenchymal state, with concomitant suppression of tumorigenicity and metastatic potential. This dichotomy results from distinct clonal trajectories impacting global epigenetic programs that are determined by the interplay between human ZEB1 and its target GRHL2. Collectively, our results indicate that susceptibility to irreversible EMT restrains clonal propagation, whereas resistance to mesenchymal reprogramming sustains disease spread in multiple models of human metastatic breast cancer, including patient-derived cells in vivo.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Molécula de Adesão da Célula Epitelial , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Mama/metabolismo , Células Clonais/metabolismo , Transição Epitelial-Mesenquimal
2.
J Exp Med ; 219(8)2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35819408

RESUMO

In certain instances, Th17 responses are associated with severe immunopathology. T cell-intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10-inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24-guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.


Assuntos
Citocinas/imunologia , Interleucina-10 , Células Th17 , Animais , Diferenciação Celular , Interleucina-10/metabolismo , Camundongos , NADH NADPH Oxirredutases/metabolismo , Transdução de Sinais , Virulência
3.
Plant Foods Hum Nutr ; 77(1): 141-149, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35247155

RESUMO

Gelling ability of a bean protein isolate (BPI) obtained from a naturally low-lectin variety (Phaseolus vulgaris var. Almonga) was analysed. For that purpose differences on gels processing: concentration (14% and 17%), salt addition (0 and 2%), and pH (6.5 -lot A- and 7 -lot B), were studied to obtain suitable colour, mechanical and viscoelastic properties for making appropriate meat and seafood analogues. Gelation at pH 7 at both 14 and 17% BPI concentrations, produced less rigid, more flexible, time-stable and cohesive gel networks. Colour of the resulting gels was white enough to be considered as an adequate base for making plant-based analogues. The content of total galactoside, inositol phosphates and trypsin inhibitors (bioactive compounds) present in one serving (100 g) of these BPI gels were up to 0.80 mg/g, 8.06 mg/g and 239 TIUs, respectively.


Assuntos
Lectinas , Phaseolus , Géis/química , Lectinas/química , Phaseolus/química , Inibidores da Tripsina
4.
Nat Commun ; 12(1): 3885, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162892

RESUMO

Cell identity is maintained by activation of cell-specific gene programs, regulated by epigenetic marks, transcription factors and chromatin organization. DNA G-quadruplex (G4)-folded regions in cells were reported to be associated with either increased or decreased transcriptional activity. By G4-ChIP-seq/RNA-seq analysis on liposarcoma cells we confirmed that G4s in promoters are invariably associated with high transcription levels in open chromatin. Comparing G4 presence, location and transcript levels in liposarcoma cells to available data on keratinocytes, we showed that the same promoter sequences of the same genes in the two cell lines had different G4-folding state: high transcript levels consistently associated with G4-folding. Transcription factors AP-1 and SP1, whose binding sites were the most significantly represented in G4-folded sequences, coimmunoprecipitated with their G4-folded promoters. Thus, G4s and their associated transcription factors cooperate to determine cell-specific transcriptional programs, making G4s to strongly emerge as new epigenetic regulators of the transcription machinery.


Assuntos
Quadruplex G , Perfilação da Expressão Gênica/métodos , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Linhagem Celular Tumoral , DNA/química , DNA/genética , DNA/metabolismo , Humanos , Conformação de Ácido Nucleico , Ligação Proteica , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição AP-1/metabolismo
5.
Nat Immunol ; 22(7): 880-892, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099917

RESUMO

Multidimensional single-cell analyses of T cells have fueled the debate about whether there is extensive plasticity or 'mixed' priming of helper T cell subsets in vivo. Here, we developed an experimental framework to probe the idea that the site of priming in the systemic immune compartment is a determinant of helper T cell-induced immunopathology in remote organs. By site-specific in vivo labeling of antigen-specific T cells in inguinal (i) or gut draining mesenteric (m) lymph nodes, we show that i-T cells and m-T cells isolated from the inflamed central nervous system (CNS) in a model of multiple sclerosis (MS) are distinct. i-T cells were Cxcr6+, and m-T cells expressed P2rx7. Notably, m-T cells infiltrated white matter, while i-T cells were also recruited to gray matter. Therefore, we propose that the definition of helper T cell subsets by their site of priming may guide an advanced understanding of helper T cell biology in health and disease.


Assuntos
Autoimunidade , Encéfalo/imunologia , Linhagem da Célula , Encefalomielite Autoimune Experimental/imunologia , Intestinos/imunologia , Pele/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Transferência Adotiva , Animais , Autoimunidade/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Sinalização do Cálcio , Líquido Cefalorraquidiano/imunologia , Líquido Cefalorraquidiano/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Cloridrato de Fingolimode/farmacologia , Perfilação da Expressão Gênica , Genes Codificadores dos Receptores de Linfócitos T , Células HEK293 , Humanos , Imunossupressores/farmacologia , Intestinos/efeitos dos fármacos , Microscopia Intravital , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/metabolismo , Fenótipo , Estudos Prospectivos , RNA-Seq , Receptores CXCR6/genética , Receptores CXCR6/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Análise de Célula Única , Pele/efeitos dos fármacos , Pele/metabolismo , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/transplante , Transcriptoma
6.
Food Chem ; 364: 130308, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34157591

RESUMO

Fish is one of the eight major foods causing type-I food allergy, and the prevalence of its allergy is increasing in part due to changes in consumption habits. One of the main drivers for these changes has been the processing developments transforming the fish muscle into seafood products. Most fish allergic patients react to the Ca2+-binding protein ß-parvalbumin (ß-PV) abundant in muscle. Here we have analyzed the effect of processing in the content and allergenic properties of the ß-PV. We found that the transformation process decreases the ß-PV content (4.7 ± 0.3 mg/g muscle, 0.24 ± 0.03 mg/g surimi, ≤0.003 ± 0.001 mg/g in seafood products), reduces the specific-IgE binding and prevents allergy relevant properties such the protease resistance and amyloid aggregation. These results suggest seafood products as potentially tolerable foods for fish allergic patients, but milk and egg allergic patients should be aware of the presence relevant additives.


Assuntos
Hipersensibilidade Alimentar , Parvalbuminas , Alérgenos , Animais , Produtos Pesqueiros , Humanos , Músculos , Alimentos Marinhos
7.
Plant Foods Hum Nutr ; 75(4): 642-650, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33097987

RESUMO

Recently, legume protein isolates are increasingly of interest as ingredients for the food industry; however, in spite of their health benefits, there is a limited information about the presence of bioactive compounds in the protein isolates. The objective of this study was to establish the phytochemical composition and selected techno-functional properties of pea and bean flours and their protein isolates obtained applying different drying methods. Regarding proximate composition, bean flour contained higher amounts of total protein (23%) and fat (44%) than pea flour; bean protein isolate (BPI) contained higher total and soluble protein, fat and starch than the pea protein isolate (PPI). Both protein isolates showed a similar emulsifying capacity (around 27%). Emulsion stability and foaming capacity were higher in the PPI (around 36%). Bean flour contained lower amounts of α-galactosides (31.64 mg/g) but a higher trypsin inhibitors content (21.95 TIU/mg) than pea flour. The preparation procedure of the protein isolates affected the bioactive compound content. The PPI showed a reduction of inositol phosphates (13%), galactosides (76%), trypsin inhibitors (90%) and total phenolic compounds (35%) compared to its whole flour. The BPI contained higher amounts of inositol phosphates (137%) and total phenolic compounds (135%) than its flour, while it showed a lower content of galactosides (54%) and a similar amount of trypsin inhibitors. Thus, the bioactive compound content and the functional properties studied indicate that protein isolates can be used as ingredients with added-value in the development of new formulated food products, allowing their increasing use in the food industry.


Assuntos
Fabaceae , Farinha , Pisum sativum , Compostos Fitoquímicos , Inibidores da Tripsina
8.
Int J Biol Macromol ; 158: 865-874, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32380111

RESUMO

The purpose of this research was to investigate the cryoprotective role of EWP-XO in the prevention of oxidative and structural changes in the myofibrillar proteins (MPs). Different concentrations of egg white protein and xylooligosaccharide (EWP-XO) mixture (0, 2, 4 and 6%) were added to the MPs of Culter alburnus fish during frozen storage (-18 °C) of 60 days. During the study, it was observed that EWP-XO significantly (P < .05) reduced the Ca-ATPase activity, which is greatly related with tertiary structural changes. Meanwhile, carbonyl contents of MPs increased in line with frozen storage (control samples). Meanwhile, samples treated with 6% EWP-XO showed less increase in carbonyl content indicating the decreased protein oxidation. The addition of EWP-XO efficiently inhibited the decline in the sulfhydryl contents. Furthermore, through circular dichroism analysis it was confirmed that the addition of EWP-XO increased the secondary structural stability by preventing the reduction in α-helix content. Microstructural analysis confirmed the preservation of a well-structured protein network that reduced the porosity and protein aggregation of MPs gel. It was concluded that 6% EWP-XO was an effective cryoprotectant mixture, which preserved the functional and structural properties of Culter alburnus during 60 days of frozen storage period.

9.
Br J Nutr ; 124(4): 418-431, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32252833

RESUMO

There is an urgent need to find alternative feed resources that can further substitute fishmeal in Atlantic salmon diets without compromising health and food quality, in particular during the finishing feeding period when the feed demand is highest and flesh quality effects are most significant. This study investigates efficacy of substituting a isoprotein (35 %) and isolipid (35 %) low fishmeal diet (FM, 15 %) with Antarctic krill meal (KM, 12 %) during 3 months with growing finishing 2·3 kg salmon (quadruplicate sea cages/diet). Final body weight (3·9 (se 0·04) kg) was similar in the dietary groups, but the KM group had more voluminous body shape, leaner hearts and improved fillet integrity, firmness and colour. Ectopic epithelial cells and focal Ca deposits in intestine were only detected in the FM group. Transcriptome profiling by microarray of livers showed dietary effects on several immune genes, and a panel of structural genes were up-regulated in the KM group, including cadherin and connexin. Up-regulation of genes encoding myosin heavy chain proteins was the main finding in skeletal muscle. Morphology examination by scanning electron microscopy and secondary structure by Fourier transform IR spectroscopy revealed more ordered and stable collagen architecture of the KM group. NEFA composition of skeletal muscle indicated altered metabolism of n-3, n-6 and SFA of the KM group. The results demonstrated that improved health and meat quality in Atlantic salmon fed krill meal were associated with up-regulation of immune genes, proteins defining muscle properties and genes involved in cell contacts and adhesion, altered fatty acid metabolism and fat deposition, and improved gut health and collagen structure.


Assuntos
Ração Animal/análise , Salmo salar , Alimentos Marinhos/análise , Animais , Euphausiacea , Análise de Alimentos , Qualidade dos Alimentos , Perfilação da Expressão Gênica , Fígado/metabolismo
10.
Leukemia ; 34(1): 50-62, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31201358

RESUMO

Acute myeloid leukemia (AML) is an aggressive hematologic neoplasm resulting from the malignant transformation of myeloid progenitors. Despite intensive chemotherapy leading to initial treatment responses, relapse caused by intrinsic or acquired drug resistance represents a major challenge. Here, we report that histone 3 lysine 27 demethylase KDM6A (UTX) is targeted by inactivating mutations and mutation-independent regulation in relapsed AML. Analyses of matched diagnosis and relapse specimens from individuals with KDM6A mutations showed an outgrowth of the KDM6A mutated tumor population at relapse. KDM6A expression is heterogeneously regulated and relapse-specific loss of KDM6A was observed in 45.7% of CN-AML patients. KDM6A-null myeloid leukemia cells were more resistant to treatment with the chemotherapeutic agents cytarabine (AraC) and daunorubicin. Inducible re-expression of KDM6A in KDM6A-null cell lines suppressed proliferation and sensitized cells again to AraC treatment. RNA expression analysis and functional studies revealed that resistance to AraC was conferred by downregulation of the nucleoside membrane transporter ENT1 (SLC29A1) by reduced H3K27 acetylation at the ENT1 locus. Our results show that loss of KDM6A provides cells with a selective advantage during chemotherapy, which ultimately leads to the observed outgrowth of clones with KDM6A mutations or reduced KDM6A expression at relapse.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Leucemia Mieloide Aguda/patologia , Animais , Xenoenxertos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Mutação
11.
Cell Rep ; 26(7): 1854-1868.e5, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30759395

RESUMO

Foxp3+ regulatory T (Treg) cells restrict immune pathology in inflamed tissues; however, an inflammatory environment presents a threat to Treg cell identity and function. Here, we establish a transcriptional signature of central nervous system (CNS) Treg cells that accumulate during experimental autoimmune encephalitis (EAE) and identify a pathway that maintains Treg cell function and identity during severe inflammation. This pathway is dependent on the transcriptional regulator Blimp1, which prevents downregulation of Foxp3 expression and "toxic" gain-of-function of Treg cells in the inflamed CNS. Blimp1 negatively regulates IL-6- and STAT3-dependent Dnmt3a expression and function restraining methylation of Treg cell-specific conserved non-coding sequence 2 (CNS2) in the Foxp3 locus. Consequently, CNS2 is heavily methylated when Blimp1 is ablated, leading to a loss of Foxp3 expression and severe disease. These findings identify a Blimp1-dependent pathway that preserves Treg cell stability in inflamed non-lymphoid tissues.


Assuntos
Metilação de DNA , Encefalomielite Autoimune Experimental/imunologia , Fatores de Transcrição Forkhead/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/imunologia , Linfócitos T Reguladores/imunologia , Animais , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/imunologia , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Epigênese Genética , Feminino , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/imunologia , Impressão Genômica , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/metabolismo
12.
Food Chem ; 239: 1226-1234, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28873544

RESUMO

To address the effect of absence of NaCl on myosin heavy chain polymerization during two-step surimi gelation (different setting temperatures/times -5°C/24h and 30°C/30min-followed by heating at 90°C/30min) were considered. In gel samples made without salt (Lot A), no myosin heavy chain (MHC) polymerization was observed, only aggregation, as indicated by the electrophoresis in polyacrylamide/agarose gel profile. Moreover, these gels were characterized by weakly stabilized protein networks as denoted by the dynamic oscillatory measurement and FTIR analysis, resulting in poor quality gels. On the other hand, in gels made with added salt, MHC polymerization occurred, as evidenced by the electrophoresis, and the gelation resulted in a well-stabilized protein network with good physicochemical properties.


Assuntos
Produtos Pesqueiros , Géis , Polimerização , Cloreto de Sódio , Temperatura
13.
Food Chem ; 196: 791-9, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26593556

RESUMO

This study tested the effect of adding tetra-sodium pyrophosphate, cystine and lysine as surimi gelation enhancers (Alaska Pollock) in order to reduce the sodium content of gels up to 0.3%. These gels were compared with others that contained 3% NaCl content (the amount typically used for surimi processing). To induce protein gelation, gels were first heated and then set at 5 °C/24 h. Once the physicochemical and rheological properties of the gels were determined, cystine and lysine were found to be the most effective additives improving the characteristics of low NaCl surimi gels. The action of these additives is mainly based on the induction of myofibrillar protein unfolding thus facilitating the formation of the types of bonds needed to establish an appropriate network. It was found that a setting period was needed for gel processing to maximize the effect of the additives.


Assuntos
Produtos Pesqueiros/análise , Proteínas de Peixes/química , Aditivos Alimentares/química , Sódio/análise , Animais , Manipulação de Alimentos , Gadiformes , Géis/química , Temperatura Alta , Reologia
14.
Crit Rev Food Sci Nutr ; 56(2): 237-48, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25000341

RESUMO

A general overview, focusing on new trends in the different techniques used in restructured seafood product processing has been described in this work. Heat-induced gelation has been more widely studied in scientific literature than cold gelation technology. This latter technology includes the use of hydrocolloids (alginates and glucomannan) or enzymes (microbial transglutaminase) for making both raw and cooked restructured products. In restructuration processes, fortification processing with some functional ingredients is studied, giving as a result extra value to the products as well as increasing the variety of new seafood products. The process of alleviating heavy metals and organic pollutants from the raw material used has also been reviewed in the present paper.


Assuntos
Tecnologia de Alimentos , Produtos da Carne/análise , Alimentos Marinhos/análise , Animais , Culinária , Temperatura Alta
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