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1.
Nano Lett ; 24(18): 5436-5443, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38656103

RESUMO

The ultrahigh surface area of two-dimensional materials can drive multimodal coupling between optical, electrical, and mechanical properties that leads to emergent dynamical responses not possible in three-dimensional systems. We observed that optical excitation of the WS2 monolayer above the exciton energy creates symmetrically patterned mechanical protrusions which can be controlled by laser intensity and wavelength. This observed photostrictive behavior is attributed to lattice expansion due to the formation of polarons, which are charge carriers dressed by lattice vibrations. Scanning Kelvin probe force microscopy measurements and density functional theory calculations reveal unconventional charge transport properties such as the spatially and optical intensity-dependent conversion in the WS2 monolayer from apparent n- to p-type and the subsequent formation of effective p-n junctions at the boundaries between regions with different defect densities. The strong opto-electrical-mechanical coupling in the WS2 monolayer reveals previously unexplored properties, which can lead to new applications in optically driven ultrathin microactuators.

2.
Angew Chem Int Ed Engl ; 63(5): e202316630, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38063060

RESUMO

Controlled assembly of nanoparticles into well-defined assembled architectures through precise manipulation of spatial arrangement and interactions allows the development of advanced mesoscale materials with tailored structures, hierarchical functionalities, and enhanced properties. Despite remarkable advancements, the controlled assembly of highly anisotropic 2Dnanosheets is significantly challenging, primarily due to the limited availability of selective edge-to-edge connectivity compared to the abundant large faces. Innovative strategies are needed to unlock the full potential of 2D-nanomaterialsin self-assembled structures with distinct and desirable properties. This research unveils the discovery of controlled self-assembly of 2D-silica nanosheets (2D-SiNSs) into hollow micron-sized soccer ball-like shells (SA-SiMS). The assembly is driven by the physical flexibility of the 2D-SiNSs and the differential electricdouble-layer charge gradient creating electrostatic bias on the edge and face regions. The resulting SA-SiMS structures exhibit high mechanical stability, even at high-temperatures, and exhibit excellent performance as catalyst support in the dry reforming of methane. The SA-SiMS structures facilitate improved mass transport, leading to enhanced reaction rates, while the thin silica shell prevents sintering of small catalyst nanocrystals, thereby preventing coke formation. This discovery sheds light on the controllable self-assembly of 2D nanomaterials and provides insights into the design and synthesis of advanced mesoscale materials with tailored properties.

3.
Biochem Biophys Res Commun ; 642: 154-161, 2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36580826

RESUMO

The physicochemical properties of biomaterials influence cell adhesion, shape, and polarization of macrophages. In this study, we aimed to evaluate the polarization of macrophages in terms of the regulation of cell adhesion and how synthetic mimics for heparin and poly(sodium-4-styrenesulfonate) can regulate macrophage polarization by modulating cell shape, focal adhesion, cell traction force, and intracellular tension. Our initial findings showed that macrophages cultured with heparin-mimicking polymer-based hydrogel matrix showed reduced expression of cell adhesion markers such as integrins, vinculin, RhoA, and ROCK1/2 and reduced cell shape, elongation, cell-matrix traction force, and intracellular tension. Furthermore, we observed a significant decrease in cell adhesion in cells cultured on the hydrogel, resulting in the promotion of M1 polarization. These findings offer insights into the important roles of cell-matrix interactions in macrophage polarization and offer a platform for heparin-mimicking polymer-based hydrogel matrices to induce M1 polarization by inducing cell adhesion without classical activators.


Assuntos
Hidrogéis , Polímeros , Adesão Celular , Heparina/farmacologia , Heparina/metabolismo , Macrófagos/metabolismo , Polímeros/farmacologia , Polímeros/metabolismo , Materiais Biomiméticos
4.
Immunity ; 40(4): 457-9, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24745329

RESUMO

Segmented filamentous bacteria (SFB) contribute to immune-system maturation. In this issue of Immunity, Goto et al. (2014) and Lécuyer et al. (2014) provide evidence for how SFB induce antigen-specific T helper 17 cells and promote development of adaptive immunity at discrete mucosal sites.


Assuntos
Antígenos de Bactérias/imunologia , Infecções por Clostridium/imunologia , Clostridium/imunologia , Células Dendríticas/imunologia , Infecções por Escherichia coli/imunologia , Escherichia coli/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Imunoglobulina A/metabolismo , Intestinos/imunologia , Linfócitos/imunologia , Plasmócitos/imunologia , Células Th17/imunologia , Animais
5.
Immunity ; 40(3): 355-66, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24530058

RESUMO

T helper 17 (Th17) cells can give rise to interleukin-17A (IL-17A)- and interferon (IFN)-γ-double-producing cells that are implicated in development of autoimmune diseases. However, the molecular mechanisms that govern generation of IFN-γ-producing Th17 cells are unclear. We found that coexpression of the Th1 and Th17 cell master transcription factors, T-bet and retinoid-related orphan receptor gamma-t (RORγt), respectively, did not generate Th cells with robust IL-17 and IFN-γ expression. Instead, development of IFN-γ-producing Th17 cells required T-bet and Runx1 or Runx3. IL-12-stimulated Th17 cells upregulated Runx1, which bound to the Ifng locus in a T-bet-dependent manner. Reciprocally, T-bet or Runx1 deficiency or inhibition of Runx transcriptional activity impaired the development of IFN-γ-producing Th17 cells during experimental autoimmune encephalomyelitis, which correlated with substantially ameliorated disease course. Thus, our studies identify a critical role for T-bet and Runx transcription factors in the generation of pathogenic IFN-γ-producing Th17 cells.


Assuntos
Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Interferon gama/biossíntese , Proteínas com Domínio T/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Animais , Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Subunidades alfa de Fatores de Ligação ao Core/genética , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Expressão Gênica , Loci Gênicos , Interferon gama/genética , Camundongos , Camundongos Knockout , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Ligação Proteica , Proteínas com Domínio T/genética , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/citologia
6.
J Neuroinflammation ; 19(1): 154, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35706008

RESUMO

This review provides an overview of the importance of microbiota in the regulation of gut-brain communication in immune-related neurological disorders. The gastrointestinal (GI) tract hosts a diverse abundance of microbiota, referred to as gut microbiota. The gut microbiota plays a role in the maintenance of GI tract homeostasis and is likely to have multiple effects on brain development and function. The bidirectional communication between the gut microbiota and the brain is termed the microbiota-gut-brain axis. This communication between the intestine and the brain appears to affect human health and behavior, as certain animal studies have demonstrated the association between alterations in the gut microbiota and neurological disorders. Most insights about the microbiota-gut-brain axis come from germ-free animal models, which reveal the importance of gut microbiota in neural function. To date, many studies have observed the impact of the gut microbiota in patients with neurological disorders. Although many studies have investigated the microbiota-gut-brain axis, there are still limitations in translating this research to humans given the complexities of the relationship between the gut microbiota and the brain. In this review, we discuss emerging evidence of how the microbiota-gut-brain axis regulates brain development and function through biological networks, as well as the possible contribution of the microbiota-gut-brain axis in immune-related neurological disorders.


Assuntos
Microbioma Gastrointestinal , Doenças do Sistema Imunitário , Microbiota , Doenças do Sistema Nervoso , Animais , Encéfalo/fisiologia , Humanos , Microbiota/fisiologia
7.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563294

RESUMO

Interleukin (IL)-1ß plays an important role in atherosclerosis pathogenesis. We aimed to investigate the effect of anakinra, a recombinant human IL-1 receptor antagonist, on the progression of atherosclerosis in apolipoprotein E knockout (ApoE−/−) mice. ApoE−/− mice (8-week male) were treated with saline (control), anakinra 10, 25, and 50 mg/kg, respectively (n = 10 in each group). Mice were fed a standard chow (4 weeks) followed by an atherogenic diet (35kcal% fat, 1.25% cholesterol, 12 weeks). Atheromatous plaques in ApoE−/− mice and the expression of inflammatory genes and signaling pathways in human umbilical vein endothelial cells (HUVECs), rat aortic smooth muscle cells (RAOSMCs), and 3T3-L1 adipocytes were assessed. Anakinra reduced the plaque size of the aortic arch (30.6% and 25.2% at the 25 mg/kg and 50 mg/kg doses, both p < 0.05) and serum triglyceride in ApoE−/− mice and suppressed inflammatory genes (IL-1ß and IL-6) expressions in HUVECs and RAOSMCs (all p < 0.05). In RAOSMCs, anakinra reduced metalloproteinase-9 expression in a dose-dependent manner and inhibited cell migration. Anakinra-treated mice exhibited trends of lower CD68+ macrophage infiltration in visceral fat and monocyte chemoattractant protein-1 expression was reduced in 3T3-L1 adipocytes. Anakinra could be a useful component for complementary treatment with a standard regimen to reduce the residual cardiovascular risk.


Assuntos
Aterosclerose , Proteína Antagonista do Receptor de Interleucina 1 , Placa Aterosclerótica , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Aterosclerose/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/metabolismo , Ratos , Receptores de Interleucina-1/metabolismo
8.
Environ Sci Technol ; 54(19): 11905-11914, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32852946

RESUMO

Despite the numerous studies that have investigated the occurrence and fate of plastic particles in the environment, only a limited effort has been devoted toward exploring the characteristics of dissolved organic matter (DOM) leached from microplastics. In this study, using excitation emission matrix-parallel factor analysis (EEM-PARAFAC), we explored the fluorescence signatures of plastic-derived DOM from commonly used plastic materials, which included two polymers (polyvinyl chloride (PVC) and polystyrene (PS)), two additives (diethylhexyl phthalate (DEHP) and bisphenol A (BPA)), and two commercial plastics. The exposure of the selected plastics to UV light facilitated the leaching of DOM measured in terms of dissolved organic carbon and fluorescence intensity. Four fluorescent components were identified, which included three protein/phenol-like components (C1, C3, and C4) and one humic-like component (C2). The C1 and C4 components were highly correlated with the amounts of DOM leached from DEHP and BPA, respectively, under both leaching conditions, while both C2 and C4 presented good correlations with the DOM leached from polymers under UV light. The C4 may serve as a good fluorescence proxy for DOM leached from BPA or BPA-containing plastics. This study highlights the overlooked issue of plastic-derived DOM leaching into the aquatic environment through optical characterization.


Assuntos
Microplásticos , Plásticos , Análise Fatorial , Substâncias Húmicas/análise , Polímeros , Espectrometria de Fluorescência
9.
Proc Natl Acad Sci U S A ; 114(40): 10713-10718, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28893978

RESUMO

The gut microbiota regulates T cell functions throughout the body. We hypothesized that intestinal bacteria impact the pathogenesis of multiple sclerosis (MS), an autoimmune disorder of the CNS and thus analyzed the microbiomes of 71 MS patients not undergoing treatment and 71 healthy controls. Although no major shifts in microbial community structure were found, we identified specific bacterial taxa that were significantly associated with MS. Akkermansia muciniphila and Acinetobacter calcoaceticus, both increased in MS patients, induced proinflammatory responses in human peripheral blood mononuclear cells and in monocolonized mice. In contrast, Parabacteroides distasonis, which was reduced in MS patients, stimulated antiinflammatory IL-10-expressing human CD4+CD25+ T cells and IL-10+FoxP3+ Tregs in mice. Finally, microbiota transplants from MS patients into germ-free mice resulted in more severe symptoms of experimental autoimmune encephalomyelitis and reduced proportions of IL-10+ Tregs compared with mice "humanized" with microbiota from healthy controls. This study identifies specific human gut bacteria that regulate adaptive autoimmune responses, suggesting therapeutic targeting of the microbiota as a treatment for MS.


Assuntos
Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Microbioma Gastrointestinal , Leucócitos Mononucleares/imunologia , Esclerose Múltipla/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T/imunologia , Animais , Células Cultivadas , Encefalomielite Autoimune Experimental/microbiologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Humanos , Leucócitos Mononucleares/microbiologia , Leucócitos Mononucleares/patologia , Masculino , Camundongos , Esclerose Múltipla/microbiologia , Esclerose Múltipla/patologia , Linfócitos T/microbiologia , Linfócitos T/patologia
10.
Molecules ; 25(14)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32708887

RESUMO

Diabetes mellitus is a chronic metabolic disease, and its progression leads to serious complications. Although various novel therapeutic approaches for diabetes mellitus have developed in the last three decades, its prevalence has been rising more rapidly worldwide. Silk-related materials have been used as anti-diabetic remedies in Oriental medicine and many studies have shown the effects of silk fibroin (SF) in both in vitro and in vivo models. In our previous works, we reported that hydrolyzed SF improved the survival of HIT-T15 cells under high glucose conditions and ameliorated diabetic dyslipidemia in a mouse model. However, we could not provide a precise molecular mechanism. To further evaluate the functions of hydrolyzed SF on the pancreatic ß-cell, we investigated the effects of hydrolyzed SF on the pancreatic ß-cell proliferation and regeneration in the mouse model. Hydrolyzed SF induced the expression of the proliferating cell nuclear antigen (PCNA) and reduced the apoptotic cell population in the pancreatic islets. Hydrolyzed SF treatment not only induced the expression of transcription factors involved in the pancreatic ß-cell regeneration in RT-PCR results but also increased neurogenin3 and Neuro D protein levels in the pancreas of those in the group treated with hydrolyzed SF. In line with this, hydrolyzed SF treatment generated insulin mRNA expressing small cell colonies in the pancreas. Therefore, our results suggest that the administration of hydrolyzed SF increases the pancreatic ß-cell proliferation and regeneration in C57BL/KsJ-Leprdb/db mice.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diabetes Mellitus/tratamento farmacológico , Fibroínas/farmacologia , Proteínas do Tecido Nervoso/genética , Antígeno Nuclear de Célula em Proliferação/genética , Animais , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus/patologia , Fibroínas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Medicina Tradicional do Leste Asiático , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Regeneração/efeitos dos fármacos
11.
J Biol Chem ; 293(36): 13974-13988, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30042231

RESUMO

Lipid droplets are specialized cellular organelles that contain neutral lipid metabolites and play dynamic roles in energy homeostasis. Perilipin 1 (Plin1), one of the major lipid droplet-binding proteins, is highly expressed in adipocytes. In mice, Plin1 deficiency impairs peripheral insulin sensitivity, accompanied with reduced fat mass. However, the mechanisms underlying insulin resistance in lean Plin1 knockout (Plin1-/-) mice are largely unknown. The current study demonstrates that Plin1 deficiency promotes inflammatory responses and lipolysis in adipose tissue, resulting in insulin resistance. M1-type adipose tissue macrophages (ATMs) were higher in Plin1-/- than in Plin1+/+ mice on normal chow diet. Moreover, using lipidomics analysis, we discovered that Plin1-/- adipocytes promoted secretion of pro-inflammatory lipid metabolites such as prostaglandins, which potentiated monocyte migration. In lean Plin1-/- mice, insulin resistance was relieved by macrophage depletion with clodronate, implying that elevated pro-inflammatory ATMs might be attributable for insulin resistance under Plin1 deficiency. Together, these data suggest that Plin1 is required to restrain fat loss and pro-inflammatory responses in adipose tissue by reducing futile lipolysis to maintain metabolic homeostasis.


Assuntos
Tecido Adiposo/patologia , Inflamação/etiologia , Metabolismo dos Lipídeos , Perilipina-1/deficiência , Adipócitos/metabolismo , Animais , Resistência à Insulina , Lipólise , Macrófagos/patologia , Camundongos , Camundongos Knockout
12.
Immunity ; 32(5): 616-27, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20471290

RESUMO

Phenotypic plasticity of T helper 17 (Th17) cells suggests instability of chromatin structure of key genes of this lineage. We identified epigenetic modifications across the clustered Il17a and Il17f and the Ifng loci before and after differential IL-12 or TGF-beta cytokine signaling, which induce divergent fates of Th17 cell precursors. We found that Th17 cell precursors had substantial remodeling of the Ifng locus, but underwent critical additional modifications to enable high expression when stimulated by IL-12. Permissive modifications across the Il17a-Il17f locus were amplified by TGF-beta signaling in Th17 cells, but were rapidly reversed downstream of IL-12-induced silencing of the Rorc gene by the transcription factors STAT4 and T-bet. These findings reveal substantial chromatin instability of key transcription factor and cytokine genes of Th17 cells and support a model of Th17 cell lineage plasticity in which cell-extrinsic factors modulate Th17 cell fates through differential effects on the epigenetic status of Th17 cell lineage factors.


Assuntos
Epigênese Genética , Instabilidade Genômica , Interleucina-17 , Fator de Transcrição STAT4 , Proteínas com Domínio T , Subpopulações de Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Linhagem da Célula , Células Cultivadas , Citometria de Fluxo , Inativação Gênica , Loci Gênicos , Immunoblotting , Interleucina-17/genética , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Transdução de Sinais , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Fatores de Transcrição/genética
13.
J Dairy Sci ; 102(8): 6959-6970, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31255265

RESUMO

In this paper, we report the physicochemical and sensory properties of milk supplemented with a powder of microencapsulated lactase. The core material was lactase (ß-galactosidase), the primary coating material was medium-chain triglyceride (MCT), and the secondary (enteric) coating material was either hydroxypropyl methylcellulose phthalate (HPMCP) or shellac, comparing both against market milk as a control. The physicochemical properties of both types of microcapsules were analyzed, including the particle size, zeta potential, and in vitro release behavior. To survey the stability of the microcapsules in milk during storage, we studied the residual lactose content and pH. Furthermore, to determine the properties of milk supplemented with the microcapsules, changes in color and sensory properties were evaluated during storage. The particle sizes (volume-weighted mean; D[4,3]) of the microcapsules coated with HPMCP or shellac were 2,836 and 7,834 nm, respectively, and the zeta potential of the capsules coated with shellac was higher than the zeta potential of those coated with HPMCP. The pH levels of milk supplemented with the lactase microcapsules were similar to those of the control (unsupplemented market milk); however, for milk supplemented with HPMCP-coated microcapsules, the pH was slightly lower. The core material, lactase, was released from the microcapsules during 12-d storage, and 18.82 and 35.09% of lactose was hydrolyzed in the samples for HPMCP- and shellac-coated microcapsules, respectively. The sensory characteristics of milk containing microcapsules coated with HPMCP did not show significant differences from the control, in terms of sweetness or off-taste, until 8 d of storage. However, shellac-coated microcapsules showed significant difference in sweetness and off-taste at d 8 and 6 of storage, respectively. The color of milk containing HPMCP-coated microcapsules did not show a significant difference during storage. However, that containing shellac-coated microcapsules was somewhat higher in color values than others. In particular, it showed significance from 0 to 4 d storage in L* and C* values. In conclusion, a powder of lactase microcapsules coated with HPMCP can be suitable as a supplement for milk.


Assuntos
Suplementos Nutricionais , Kluyveromyces/enzimologia , Lactase/administração & dosagem , Metilcelulose/análogos & derivados , Leite/química , Animais , Cápsulas , Fenômenos Químicos , Composição de Medicamentos/veterinária , Proteínas Fúngicas/administração & dosagem , Hidrólise , Lactose/metabolismo , Metilcelulose/química , Leite/metabolismo , Tamanho da Partícula , Pós , Resinas Vegetais/química , Paladar , Triglicerídeos/química
14.
Int J Mol Sci ; 20(21)2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31653062

RESUMO

The gastrointestinal (GI) tract is a highly complex organ composed of the intestinal epithelium layer, intestinal microbiota, and local immune system. Intestinal microbiota residing in the GI tract engages in a mutualistic relationship with the host. Different sections of the GI tract contain distinct proportions of the intestinal microbiota, resulting in the presence of unique bacterial products in each GI section. The intestinal microbiota converts ingested nutrients into metabolites that target either the intestinal microbiota population or host cells. Metabolites act as messengers of information between the intestinal microbiota and host cells. The intestinal microbiota composition and resulting metabolites thus impact host development, health, and pathogenesis. Many recent studies have focused on modulation of the gut microbiota and their metabolites to improve host health and prevent or treat diseases. In this review, we focus on the production of microbial metabolites, their biological impact on the intestinal microbiota composition and host cells, and the effect of microbial metabolites that contribute to improvements in inflammatory bowel diseases and metabolic diseases. Understanding the role of microbial metabolites in protection against disease might offer an intriguing approach to regulate disease.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/patologia , Doenças Metabólicas/patologia , Bactérias/química , Bactérias/metabolismo , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/toxicidade , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/toxicidade , Flavonas/metabolismo , Flavonas/toxicidade , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Doenças Metabólicas/metabolismo , Doenças Metabólicas/microbiologia , Poliaminas/metabolismo , Poliaminas/toxicidade
15.
Immunity ; 30(1): 92-107, 2009 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-19119024

RESUMO

Development of T helper (Th) 17 cells requires transforming growth factor (TGF)-beta and interleukin (IL)-6 and is independent of the Th1 pathway. Although T cells that produce interferon (IFN)-gamma are a recognized feature of Th17 cell responses, mice deficient for STAT4 and T-bet-two prototypical Th1 transcription factors-are protected from autoimmunity associated with Th17 pathogenesis. To examine the fate and pathogenic potential of Th17 cells and origin of IFN-gamma-producing T cells that emerge during Th17 immunity, we developed IL-17F reporter mice that identify cells committed to expression of IL-17F and IL-17A. Th17 cells required TGF-beta for sustained expression of IL-17F and IL-17A. In the absence of TGF-beta, both IL-23 and IL-12 acted to suppress IL-17 and enhance IFN-gamma production in a STAT4- and T-bet-dependent manner, albeit with distinct efficiencies. These results support a model of late Th17 developmental plasticity with implications for autoimmunity and host defense.


Assuntos
Linhagem da Célula/imunologia , Interleucina-17/metabolismo , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Células Th2/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Células Cultivadas , Citometria de Fluxo , Interferon gama/metabolismo , Interleucina-23/metabolismo , Camundongos , Camundongos Knockout
17.
Proc Natl Acad Sci U S A ; 112(19): 6074-9, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25918410

RESUMO

EWS (Ewing sarcoma) encodes an RNA/ssDNA binding protein that is frequently rearranged in a number of different cancers by chromosomal translocations. Physiologically, EWS has diverse and essential roles in various organ development and cellular processes. In this study, we uncovered a new role of EWS in mitochondrial homeostasis and energy metabolism. Loss of EWS leads to a significant decrease in mitochondria abundance and activity, which is caused by a rapid degradation of Peroxisome proliferator-activated receptor γ Coactivator (PGC-1α), a central regulator of mitochondria biogenesis, function, and cellular energy metabolism. EWS inactivation leads to increased ubiquitination and proteolysis of PGC-1α via proteasome pathway. Complementation of EWS in Ews-deficient cells restores PGC-1α and mitochondrial abundance. We found that expression of E3 ubiquitin ligase, FBXW7 (F-box/WD40 domain protein 7), is increased in the absence of Ews and depletion of Fbxw7 in Ews-null cells restores PGC-1α expression and mitochondrial density. Consistent with these findings, mitochondrial abundance and activity are significantly reduced in brown fat and skeletal muscles of Ews-deficient mice. Furthermore, expression of mitochondrial biogenesis, respiration and fatty acid ß-oxidation genes is significantly reduced in the liver of Ews-null mice. These results demonstrate a novel role of EWS in mitochondrial and cellular energy homeostasis by controlling PGC-1α protein stability, and further implicate altered mitochondrial and energy metabolism in cancers harboring the EWS translocation.


Assuntos
Mitocôndrias/metabolismo , Proteína EWS de Ligação a RNA/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , DNA Mitocondrial/metabolismo , Metabolismo Energético , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Homeostase , Humanos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Músculo Esquelético/metabolismo , Oxigênio/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Conformação Proteica , Proteína EWS de Ligação a RNA/metabolismo , Ubiquitina/química , Ubiquitina-Proteína Ligases/metabolismo
18.
Int J Food Sci Nutr ; 69(3): 308-317, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28770639

RESUMO

This study was carried out to investigate the efficiency of red ginseng nanopowder in preventing collagen-induced arthritis (CIA) in mice. The mice were divided into five groups: normal group (no immunisation), control (CIA), powdered red ginseng (PRG), nanopowdered red ginseng (NRG) and methotrexate (MTX). Administering MTX, PRG and NRG to arthritic mice significantly decreased spleen indexes, clinical and histological scores compared to control group. Serum analysis of NRG and MTX groups showed a reduction in the cytokines such as the levels of tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1ß (IL-1ß) in comparison to PRG group. The levels of immunoglobulin M (IgM) and immunoglobulin G1 (IgG1) in the NRG group were significantly lower than those of the PRG group. In summary, the present study indicated that NRG can be effective in preventing type II collagen-induced rheumatoid arthritis in mice.


Assuntos
Artrite Experimental/prevenção & controle , Colágeno Tipo II/efeitos adversos , Panax/química , Preparações de Plantas/farmacologia , Animais , Artrite Experimental/tratamento farmacológico , Citocinas/sangue , Ginsenosídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos DBA , Tamanho do Órgão/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/metabolismo
19.
J Pathol ; 240(3): 304-314, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27514024

RESUMO

Several recurrent mutations and epigenetic changes have been identified in advanced gastric cancer, but the genetic alterations associated with early gastric carcinogenesis and malignant transformation remain unclear. We investigated the genomic and transcriptomic landscape of adenomas with low-grade dysplasia (LGD) and high-grade dysplasia (HGD), and intestinal-type early gastric cancer (EGC). The results were validated in an independent cohort that included EGCs directly adjacent to adenoma (EGC-adenomas) that were in the process of malignant transformation, and de novo EGCs that do not seem to have been derived from adenoma. The expression patterns clearly divided into normal, LGD, and EGC, whereas those of HGD overlapped with LGD or EGC. These results suggest that HGD is the critical stage determining malignant transformation. We found that genes related to focal adhesion and extracellular matrix receptor interaction pathways were upregulated as LGD progressed to EGC, whereas canonical Wnt signalling and peroxisome proliferator-activated receptor (PPAR) signalling pathway genes were downregulated in EGC. Genomic alterations such as somatic mutation, gene fusion and copy number variation increased gradually from LGD to EGC. APC mutations were present in 67% of LGDs, 58% of HGDs, and 18% of EGCs. RNF43 mutations were present only in HGD and EGC, and TP53 mutations were present only in EGC. In a validation cohort, RNF43 mutations were present in 35.2% of EGC-adenomas, but in only 8.6% of de novo EGCs. This is the first study to investigate the genomic and transcriptomic landscape of multistep gastric carcinogenesis. We investigated important alterations and their related pathways in each step as tumours progressed from LGD to HGD and eventually to EGC. We suggest that mutations and downregulation of RNF43 may play a critical role in the transition from adenoma to carcinoma. Given these findings and Wnt dependency in tumours with RNF43 mutation, intestinal-type gastric cancer or adenoma with RNF43 mutation might represent a promising indication for Wnt-targeted agents. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenoma/genética , Carcinogênese/genética , Carcinoma/genética , Proteínas de Ligação a DNA/genética , Proteínas Oncogênicas/genética , Neoplasias Gástricas/genética , Proteínas Wnt/genética , Adenoma/patologia , Carcinoma/patologia , Transformação Celular Neoplásica/genética , Estudos de Coortes , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Fusão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Intestinos/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Oncogênicas/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais , Neoplasias Gástricas/patologia , Transcriptoma , Ubiquitina-Proteína Ligases , Proteínas Wnt/metabolismo
20.
Int J Food Sci Nutr ; 68(8): 931-940, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28359214

RESUMO

Oyster shell is one of the foremost natural sources of calcium and is used as an alternative treatment for osteoporosis. In this study, we demonstrated that zinc-activated nanopowdered oyster shell (Zn-NPOS) effectively reduced bone loss compared with powdered oyster shell (POS) in an ovariectomized rat (OVX) model. As a result of nanosizing, the solubility and bioavailability of the oyster shell were greatly improved, and its effectiveness was further enhanced by zinc activation. Bone analysis indicated greater recovery from ovariectomy-induced bone loss following Zn-NPOS treatment. Moreover, Zn-NPOS treatment resulted in higher bone strength and superior trabecular architecture compared with NPOS and POS treatments. Furthermore, Zn-NPOS showed greater efficiency in increasing bone formation and reducing bone resorption markers. Therefore, nanosizing with zinc activation could be a viable strategy for improving the efficiency of oyster shells used for osteoporosis prevention.


Assuntos
Exoesqueleto/química , Densidade Óssea/efeitos dos fármacos , Carbonato de Cálcio/farmacologia , Carbonato de Cálcio/farmacocinética , Osteoporose/prevenção & controle , Ostreidae , Animais , Disponibilidade Biológica , Carbonato de Cálcio/química , Feminino , Osteogênese/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Sprague-Dawley
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