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1.
Science ; 373(6556): 813-818, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385401

RESUMO

A Western-style, high-fat diet promotes cardiovascular disease, in part because it is rich in choline, which is converted to trimethylamine (TMA) by the gut microbiota. However, whether diet-induced changes in intestinal physiology can alter the metabolic capacity of the microbiota remains unknown. Using a mouse model of diet-induced obesity, we show that chronic exposure to a high-fat diet escalates Escherichia coli choline catabolism by altering intestinal epithelial physiology. A high-fat diet impaired the bioenergetics of mitochondria in the colonic epithelium to increase the luminal bioavailability of oxygen and nitrate, thereby intensifying respiration-dependent choline catabolism of E. coli In turn, E. coli choline catabolism increased levels of circulating trimethlamine N-oxide, which is a potentially harmful metabolite generated by gut microbiota.


Assuntos
Colo/fisiologia , Dieta Hiperlipídica , Escherichia coli/metabolismo , Mucosa Intestinal/fisiologia , Metilaminas/metabolismo , Animais , Hipóxia Celular , Colina/administração & dosagem , Colina/metabolismo , Colo/citologia , Metabolismo Energético , Células Epiteliais/fisiologia , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Fezes/microbiologia , Microbioma Gastrointestinal , Inflamação , Mucosa Intestinal/metabolismo , Masculino , Metilaminas/sangue , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Nitratos/metabolismo , Obesidade , Consumo de Oxigênio
2.
Int J Mol Sci ; 22(14)2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34299297

RESUMO

The epithelial cell tight junction structure is the site of the transepithelial movement of solutes and water between epithelial cells (paracellular permeability). Paracellular permeability can be divided into two distinct pathways, the Pore Pathway mediating the movement of small ions and solutes and the Leak Pathway mediating the movement of large solutes. Claudin proteins form the basic paracellular permeability barrier and mediate the movement of small ions and solutes via the Pore Pathway. The Leak Pathway remains less understood. Several proteins have been implicated in mediating the Leak Pathway, including occludin, ZO proteins, tricellulin, and actin filaments, but the proteins comprising the Leak Pathway remain unresolved. Many aspects of the Leak Pathway, such as its molecular mechanism, its properties, and its regulation, remain controversial. In this review, we provide a historical background to the evolution of the Leak Pathway concept from the initial examinations of paracellular permeability. We then discuss current information about the properties of the Leak Pathway and present current theories for the Leak Pathway. Finally, we discuss some recent research suggesting a possible molecular basis for the Leak Pathway.


Assuntos
Células Epiteliais/metabolismo , Junções Íntimas/metabolismo , Animais , Claudinas/metabolismo , Células Epiteliais/fisiologia , Humanos , Ocludina/metabolismo , Permeabilidade , Junções Íntimas/fisiologia , Proteína da Zônula de Oclusão-1/metabolismo , Proteína da Zônula de Oclusão-2/metabolismo
3.
Am J Physiol Regul Integr Comp Physiol ; 321(1): R79-R90, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34105399

RESUMO

Although recognized as an important endocrine organ, little is known about the mechanisms through which adipose tissue can regulate inflammatory responses in distant tissues, such as lung that are affected by obesity. To explore potential mechanisms, male C57BL/6J mice were provided either high-fat diet, low-fat diet, or were provided a high-fat diet then switched to the low-fat diet to promote weight loss. Visceral adipocytes were then cultured in vitro to generate conditioned media (CM) that was used to treat both primary (mouse tracheal epithelial cells; MTECs) and immortalized (mouse-transformed club cells; MTCCs) airway epithelial cells. Adiponectin levels were greatly depressed in the CM from both obese and diet-switched adipocytes relative to mice continually fed the low-fat diet. MTECs from mice with obesity secreted higher baseline levels of inflammatory cytokines than MTECs from lean or diet-switched mice. MTECs treated with obese adipocyte CM increased their secretion of these cytokines compared with MTECs treated with lean CM. Diet-switched CM modestly decreased the production of cytokines compared with obese CM, and these effects were recapitulated when the CM was used to treat MTCCs. Adipose stromal vascular cells from mice with obesity expressed genes consistent with an M1 macrophage phenotype and decreased eosinophil abundance compared with lean stromal vascular fraction, a profile that persisted in the lean diet-switched mice despite substantial weight loss. Soluble factors secreted from obese adipocytes exert a proinflammatory effect on airway epithelial cells, and these alterations are attenuated by diet-induced weight loss, which could have implications for the airway dysfunction related to obese asthma and its mitigation by weight loss.


Assuntos
Adipócitos/fisiologia , Tecido Adiposo/citologia , Células Epiteliais/fisiologia , Inflamação/complicações , Obesidade/induzido quimicamente , Animais , Linhagem Celular , Técnicas de Cocultura , Dieta Hiperlipídica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sistema Respiratório/citologia
4.
Res Vet Sci ; 138: 167-177, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34153557

RESUMO

Adhesion molecules play an important role in urinary calculus formation. The expressions of adhesion molecules in renal tubular has been reported in some animals. However, the role of adhesion molecules in the process of sheep urinary calculus formation is still unclear. The magnesium ammonium phosphate (MAP) is the main component of sheep urinary calculus. In this paper, the sheep renal tubular epithelial cells (RTECs) were isolated and treated with MAP, the expressions of osteopontin (OPN), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and apoptosis-related indicators caspase-3, Bcl-2 and Bax in RTECs were observed, the viability of RTECs was detected by Cell Counting Kit-8 (CCK-8). The levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and the expressions of inflammatory factors Interleukin-6 (IL-6), Interleukin-1 (IL-1), Interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent (ELISA). The histopathological observation of kidney in urolithiasis sheep was made. The results showed that MAP could reduce the viability and SOD activity, enhance the activity of MDA significantly and promote the expressions of IL-1, IL-6, IL-17 and TNF-α of RTECs. By western blot and qPCR methods, the expressions of ICAM-1, VCAM-1 and OPN increased in 48 h. In addition, the expression of caspase-3 increased significantly and the ratio of Bcl-2/Bax reduced with exposure to MAP. The renal tissue structure was seriously damaged, the RTECs in urolithiasis sheep were degenerative and necrotic.


Assuntos
Apoptose , Moléculas de Adesão Celular/metabolismo , Sobrevivência Celular , Citocinas/imunologia , Células Epiteliais/fisiologia , Estresse Oxidativo , Estruvita/metabolismo , Animais , Células Cultivadas , Molécula 1 de Adesão Intercelular/metabolismo , Rim/fisiologia , Osteopontina/metabolismo , Carneiro Doméstico/metabolismo , Carneiro Doméstico/urina , Cálculos Urinários/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
5.
Nat Commun ; 12(1): 3933, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168132

RESUMO

Thymic T cell development and T cell receptor repertoire selection are dependent on essential molecular cues provided by thymic epithelial cells (TEC). TEC development and function are regulated by their epigenetic landscape, in which the repressive H3K27me3 epigenetic marks are catalyzed by polycomb repressive complex 2 (PRC2). Here we show that a TEC-targeted deficiency of PRC2 function results in a hypoplastic thymus with reduced ability to express antigens and select a normal repertoire of T cells. The absence of PRC2 activity reveals a transcriptomically distinct medullary TEC lineage that incompletely off-sets the shortage of canonically-derived medullary TEC whereas cortical TEC numbers remain unchanged. This alternative TEC development is associated with the generation of reduced TCR diversity. Hence, normal PRC2 activity and placement of H3K27me3 marks are required for TEC lineage differentiation and function and, in their absence, the thymus is unable to compensate for the loss of a normal TEC scaffold.


Assuntos
Epigênese Genética , Células Epiteliais/citologia , Complexo Repressor Polycomb 2/genética , Timo/citologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Linhagem da Célula , Células Epiteliais/fisiologia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Complexo Repressor Polycomb 2/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/citologia , Linfócitos T/fisiologia , Timócitos/citologia , Timócitos/fisiologia , Timo/fisiologia
6.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070207

RESUMO

In domestic ruminants, endometrial receptivity is related to successful pregnancy and economic efficiency. Despite several molecules having been reported in the past regarding endometrial receptivity regulation, much regarding the mechanism of endometrial receptivity regulation remains unknown due to the complex nature of the trait. In this work, we demonstrated that the cysteine-rich transmembrane bone morphogenetic protein (BMP) regulator 1 (CRIM1) served as a novel regulator in the regulation of goat endometrial receptivity in vitro. Our results showed that hormones and IFN-τ increased the expression of CRIM1 in goat endometrial epithelial cells (EECs). Knockdown of CRIM1 via specific shRNA hindered cell proliferation, cell adhesion and prostaglandins (PGs) secretion and thus derailed normal endometrial receptivity. We further confirmed that receptivity defect phenotypes due to CRIM1 interference were restored by ATG7 overexpression in EECs while a loss of ATG7 further impaired receptivity phenotypes. Moreover, our results showed that changing the expression of ATG7 affected the reactive oxygen species (ROS) production. Moreover, mR-143-5p was shown to be a potential upstream factor of CRIM1-regulated endometrial receptivity in EECs. Overall, these results suggest that CRIM1, as the downstream target of miR-143-5p, has effects on ATG7-dependent autophagy, regulating cell proliferation, cell adhesion and PG secretion, and provides a new target for the diagnosis and treatment of early pregnancy failure and for improving the success rates of artificial reproduction.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/fisiologia , Implantação do Embrião/genética , Endométrio/fisiologia , Cabras/fisiologia , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Autofagia/fisiologia , Proteína 7 Relacionada à Autofagia/deficiência , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/fisiologia , Receptores de Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Receptores de Proteínas Morfogenéticas Ósseas/genética , Adesão Celular , Proliferação de Células , Células Cultivadas , Implantação do Embrião/fisiologia , Endométrio/citologia , Endométrio/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Estradiol/farmacologia , Feminino , Técnicas de Silenciamento de Genes , Cabras/genética , Interferon Tipo I/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Gravidez , Proteínas da Gravidez/farmacologia , Progesterona/farmacologia , Prostaglandinas/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
7.
FASEB J ; 35(7): e21300, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34165809

RESUMO

GPR126 is an adhesion G protein-coupled receptor which lies on chromosome 6q24. Genetic variants in this region are reproducibly associated with lung function and COPD in genome wide association studies (GWAS). The aims of this study were to define the role of GPR126 in the human lung and in pulmonary disease and identify possible casual variants. Online tools (GTEx and LDlink) identified SNPs which may have effects on GPR126 function/ expression, including missense variant Ser123Gly and an intronic variant that shows eQTL effects on GPR126 expression. GPR126 signaling via cAMP-mediated pathways was identified in human structural airway cells when activated with the tethered agonist, stachel. RNA-seq was used to identify downstream genes/ pathways affected by stachel-mediated GPR126 activation in human airway smooth muscle cells. We identified ~350 differentially expressed genes at 4 and 24 hours post stimulation with ~20% overlap. We identified that genes regulated by GPR126 activation include IL33, CTGF, and SERPINE1, which already have known roles in lung biology. Pathways altered by GPR126 included those involved in cell cycle progression and cell proliferation. Here, we suggest a role for GPR126 in airway remodeling.


Assuntos
Brônquios/fisiologia , Células Epiteliais/fisiologia , Músculo Liso/fisiologia , Mutação de Sentido Incorreto , Doença Pulmonar Obstrutiva Crônica/patologia , Receptores Acoplados a Proteínas G/genética , Sistema Respiratório/fisiopatologia , Brônquios/citologia , Proliferação de Células , Células Cultivadas , Células Epiteliais/citologia , Genômica , Humanos , Músculo Liso/citologia , Doença Pulmonar Obstrutiva Crônica/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
8.
Theranostics ; 11(11): 5248-5266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859745

RESUMO

Mesenchymal stem cells-derived exosomes (MSC-exos) have attracted great interest as a cell-free therapy for acute kidney injury (AKI). However, the in vivo biodistribution of MSC-exos in ischemic AKI has not been established. The potential of MSC-exos in promoting tubular repair and the underlying mechanisms remain largely unknown. Methods: Transmission electron microscopy, nanoparticle tracking analysis, and western blotting were used to characterize the properties of human umbilical cord mesenchymal stem cells (hucMSCs) derived exosomes. The biodistribution of MSC-exos in murine ischemia/reperfusion (I/R) induced AKI was imaged by the IVIS spectrum imaging system. The therapeutic efficacy of MSC-exos was investigated in renal I/R injury. The cell cycle arrest, proliferation and apoptosis of tubular epithelial cells (TECs) were evaluated in vivo and in HK-2 cells. The exosomal miRNAs of MSC-exos were profiled by high-throughput miRNA sequencing. One of the most enriched miRNA in MSC-exos was knockdown by transfecting miRNA inhibitor to hucMSCs. Then we investigated whether this candidate miRNA was involved in MSC-exos-mediated tubular repair. Results: Ex vivo imaging showed that MSC-exos was efficiently homing to the ischemic kidney and predominantly accumulated in proximal tubules by virtue of the VLA-4 and LFA-1 on MSC-exos surface. MSC-exos alleviated murine ischemic AKI and decreased the renal tubules injury in a dose-dependent manner. Furthermore, MSC-exos significantly attenuated the cell cycle arrest and apoptosis of TECs both in vivo and in vitro. Mechanistically, miR-125b-5p, which was highly enriched in MSC-exos, repressed the protein expression of p53 in TECs, leading to not only the up-regulation of CDK1 and Cyclin B1 to rescue G2/M arrest, but also the modulation of Bcl-2 and Bax to inhibit TEC apoptosis. Finally, inhibiting miR-125b-5p could mitigate the protective effects of MSC-exos in I/R mice. Conclusion: MSC-exos exhibit preferential tropism to injured kidney and localize to proximal tubules in ischemic AKI. We demonstrate that MSC-exos ameliorate ischemic AKI and promote tubular repair by targeting the cell cycle arrest and apoptosis of TECs through miR-125b-5p/p53 pathway. This study provides a novel insight into the role of MSC-exos in renal tubule repair and highlights the potential of MSC-exos as a promising therapeutic strategy for AKI.


Assuntos
Injúria Renal Aguda/genética , Exossomos/genética , Túbulos Renais Proximais/fisiologia , Células-Tronco Mesenquimais/fisiologia , MicroRNAs/genética , Traumatismo por Reperfusão/genética , Proteína Supressora de Tumor p53/genética , Injúria Renal Aguda/fisiopatologia , Animais , Apoptose/genética , Proteína Quinase CDC2/genética , Pontos de Checagem do Ciclo Celular/genética , Divisão Celular/genética , Linhagem Celular , Proliferação de Células/genética , Ciclina B1/genética , Células Epiteliais/fisiologia , Fase G2/genética , Humanos , Isquemia/genética , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2/genética , Traumatismo por Reperfusão/fisiopatologia , Distribuição Tecidual/genética , Proteína X Associada a bcl-2/genética
9.
Aging (Albany NY) ; 13(8): 11218-11233, 2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33820870

RESUMO

Human breast milk (HBM) provides essential nutrients for newborn growth and development, and contains a variety of biologically active ingredients that can affect gastrointestinal tract and immune system development in breastfed infants. HBM also contains mRNAs, microRNAs and lncRNAs, most of which are encapsulated in milk-derived exosomes and exhibit various important infant development related biological functions. While previous studies have shown that exosomal circRNAs are involved in the intestinal epithelial cells' proliferation and repair. However, the effect of HBM exosomal circRNAs on intestinal development is not clear. In this study, we identified 6756 circRNAs both in preterm colostrum (PC) and term colostrum (TC), of which 66 were upregulated, and 42 were downregulated (|fold change>2|, p < 0.05) in PC. Pathway analysis showed that the VEGF signalling pathway was involved, and network analysis revealed that the differentially expressed circRNAs bound various miRNAs. Further analyses showed that has_circRNA_405708 and has_circRNA_104707 were involved in the VEGF signalling pathway, and that they all bound various mirRNAs. Exosomes found in preterm colostrum (PC) and term colostrum (TC) promoted VEGF protein expression and induced the proliferation and migration of small intestinal epithelial cells (FHCs). Exosomal circRNAs found in human colostrum (HC) binding to related miRNAs may regulate VEGF signalling, and intestinal development.


Assuntos
Colostro/metabolismo , Intestinos/crescimento & desenvolvimento , RNA Circular/metabolismo , Transdução de Sinais/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Aleitamento Materno , Linhagem Celular , Movimento Celular/genética , Proliferação de Células/genética , Desenvolvimento Infantil , Colostro/citologia , Meios de Cultura/metabolismo , Células Epiteliais/fisiologia , Exossomos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro/crescimento & desenvolvimento , Idade Materna , MicroRNAs/metabolismo , Gravidez , RNA Circular/isolamento & purificação , Adulto Jovem
10.
Biomed Pharmacother ; 139: 111583, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33901875

RESUMO

TMEM16A is a Ca2+-activated Cl- channel involved in mucus secretion in inflamed airways and proposed as a drug target for diseases associated with mucus hypersecretion including asthma. This study aimed to identify novel inhibitors of TMEM16A-mediated Cl- secretion in airway epithelial cells from a collection of compounds isolated from fungi indigenous in Thailand and examine its potential utility in mitigating airway mucus secretion using Calu-3 cells as a study model. Screening of > 400 fungal metabolites revealed purpactin A isolated from a soil-derived fungus Penicillium aculeatum PSU-RSPG105 as an inhibitor of TMEM16A-mediated Cl- transport with an IC50 value of ~2 µM. A consistent inhibitory effect of purpactin A on TMEM16A were observed regardless of TMEM16A activators or in the presence of an inhibitor of Ca2+/calmodulin-dependent protein kinase II (CaMKII), a negative regulator of TMEM16A. In addition, purpactin A did not affect cell viability, epithelial barrier integrity and activities of membrane transport proteins essential for maintaining airway hydration including CFTR Cl- channels and apical BK K+ channels. Intriguingly, purpactin A prevented a Ca2+-induced mucin release in cytokine-treated airway cells. Taken together, purpactin A represents the first class of TMEM16A inhibitor derived from fungus, which may be beneficial for the treatment of diseases associated with mucus hypersecretion.


Assuntos
Anoctamina-1/antagonistas & inibidores , Células Epiteliais/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Mucinas/metabolismo , Animais , Anoctamina-1/metabolismo , Anoctamina-1/fisiologia , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Humanos , Ratos Endogâmicos F344 , Sistema Respiratório/citologia , Talaromyces
11.
Cell Mol Life Sci ; 78(12): 5051-5068, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33864479

RESUMO

Mammalian lungs are metabolically active organs that frequently encounter environmental insults. Stress responses elicit protective autophagy in epithelial barrier cells and the supportive niche. Autophagy promotes the recycling of damaged intracellular organelles, denatured proteins, and other biological macromolecules for reuse as components required for lung cell survival. Autophagy, usually induced by metabolic defects, regulates cellular metabolism. Autophagy is a major adaptive response that protects cells and organisms from injury. Endogenous region-specific stem/progenitor cell populations are found in lung tissue, which are responsible for epithelial repair after lung damage. Additionally, glucose and fatty acid metabolism is altered in lung stem/progenitor cells in response to injury-related lung fibrosis. Autophagy deregulation has been observed to be involved in the development and progression of other respiratory diseases. This review explores the role and mechanisms of autophagy in regulating lung metabolism and epithelial repair.


Assuntos
Autofagia , Células Epiteliais/fisiologia , Pneumopatias/fisiopatologia , Pulmão/fisiologia , Animais , Células Epiteliais/citologia , Humanos , Pulmão/citologia
12.
Biomed Environ Sci ; 34(4): 272-281, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33894806

RESUMO

Objective: This study aimed to use an air-liquid interface (ALI) exposure system to simulate the inhalation exposure of motorcycle exhaust particulates (MEPs) and then investigate the benchmark dose (BMD) of MEPs by evaluating cell relative viability (CRV) in lung epithelial BEAS-2B cells. Methods: The MEPs dose was characterized by measuring the number concentration (NC), surface area concentration (SAC), and mass concentration (MC). BEAS-2B cells were exposed to MEPs at different concentrations via ALI and CRV was determined using Cell Counting Kit (CCK-8) assay. BMD software was applied to calculate BMD and the lower limit of benchmark dose (BMDL) according to Akaike Information Coefficient (AIC), with P-value based on Hill, Linear, Polynomial, and Power model. Results: Our results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model, while MC was estimated by Polynomial model. The BMDL for CRV following ALI exposure to MEPs were as follows: 364.2#/cm 3 for NC; 0.662 × 10 7 nm 2/cm 3 for SAC; and 0.278 µg/m 3 for MC. Conclusion: These results indicate that MEPs exposure via ALI system induces a dose-dependent decrease of CRV and provides the potential exposure threshold of MEPs in a lung cell model.


Assuntos
Benchmarking/estatística & dados numéricos , Brônquios/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Motocicletas , Material Particulado/efeitos adversos , Emissões de Veículos/análise , Brônquios/fisiologia , Linhagem Celular , Células Epiteliais/fisiologia , Humanos
13.
Int J Mol Sci ; 22(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801524

RESUMO

Tight junctions play a major role in maintaining the integrity and impermeability of the intestinal barrier. As such, they act as an ideal target for pathogens to promote their translocation through the intestinal mucosa and invade their host. Different strategies are used by pathogens, aimed at directly destabilizing the junctional network or modulating the different signaling pathways involved in the modulation of these junctions. After a brief presentation of the organization and modulation of tight junctions, we provide the state of the art of the molecular mechanisms leading to permeability breakdown of the gut barrier as a consequence of tight junctions' attack by pathogens, including bacteria, viruses, fungi, and parasites.


Assuntos
Bactérias/patogenicidade , Células Epiteliais/fisiologia , Infecções/fisiopatologia , Enteropatias/fisiopatologia , Mucosa Intestinal/fisiologia , Junções Íntimas/fisiologia , Animais , Permeabilidade da Membrana Celular , Humanos , Infecções/microbiologia , Enteropatias/microbiologia , Transdução de Sinais
14.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805523

RESUMO

The intestinal epithelium serves as a dynamic barrier to protect the host tissue from exposure to a myriad of inflammatory stimuli in the luminal environment. Intestinal epithelial cells (IECs) encompass differentiated and specialized cell types that are equipped with regulatory genes, which allow for sensing of the luminal environment. Potential inflammatory cues can instruct IECs to undergo a diverse set of phenotypic alterations. Aging is a primary risk factor for a variety of diseases; it is now well-documented that aging itself reduces the barrier function and turnover of the intestinal epithelium, resulting in pathogen translocation and immune priming with increased systemic inflammation. In this study, we aimed to provide an effective epigenetic and regulatory outlook that examines age-associated alterations in the intestines through the profiling of microRNAs (miRNAs) on isolated mouse IECs. Our microarray analysis revealed that with aging, there is dysregulation of distinct clusters of miRNAs that was present to a greater degree in small IECs (22 miRNAs) compared to large IECs (three miRNAs). Further, miRNA-mRNA interaction network and pathway analyses indicated that aging differentially regulates key pathways between small IECs (e.g., toll-like receptor-related cascades) and large IECs (e.g., cell cycle, Notch signaling and small ubiquitin-related modifier pathway). Taken together, current findings suggest novel gene regulation pathways by epithelial miRNAs in aging within the gastrointestinal tissues.


Assuntos
Envelhecimento/fisiologia , Células Epiteliais/fisiologia , Mucosa Intestinal/citologia , MicroRNAs/fisiologia , Animais , Simulação por Computador , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Intestino Grosso/citologia , Intestino Delgado/citologia , Camundongos Endogâmicos C57BL , RNA Mensageiro
15.
Am J Chin Med ; 49(3): 661-676, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33683190

RESUMO

Ulcerative Colitis (UC) is a chronic inflammation disease, and the incidence of UC is increasing recently. Both clinical trials and animal experiments show that moxibustion is a complementary and alternative treatment for UC. Previous studies showed that moxibustion can improve UC by regulating the balance of Tregs and Th17 (Sun et al., 2017). Treg cells is one subset of CD4[Formula: see text] T cells that exert the immunosuppressive function. CD39 and CD73, expressed on the surface of Tregs, hydrolyze ATP to AMP and are further involved in the immunosuppressive function of Tregs. In this study, we investigated the effect of moxibustion on CD39[Formula: see text] Tregs and CD73[Formula: see text] Tregs in dextran sulfate sodium (DSS) induced UC mice. The A2a receptor (A2aR), one of the targets of adenosine, was also detected. The results showed that moxibustion could increase the expression of CD39, CD73, and A2aR in colonic tissue and improve the proportion of CD39[Formula: see text] Tregs and CD73[Formula: see text] Tregs in peripheral blood, inguinal draining lymph nodes and spleen in the UC model. Additionally, A2aR agonists enhanced the cell viability of colonic epithelial cells and inhibit the production of cytokines IL-6 and TNF-[Formula: see text] in vitro, which may further influence the pathway of ATP purine signal metabolism and alleviates the gut inflammation of UC mice. Taken together, this study provides supplemental evidence to reveal the immune related mechanism of moxibustion in the treatment of UC.


Assuntos
5'-Nucleotidase/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Colite Ulcerativa/genética , Colite Ulcerativa/terapia , Sulfato de Dextrana/efeitos adversos , Moxibustão/métodos , Receptor A2A de Adenosina/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Animais , Sobrevivência Celular , Colite Ulcerativa/etiologia , Colite Ulcerativa/metabolismo , Colo/citologia , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Interleucina-6/metabolismo , Camundongos , Fator de Necrose Tumoral alfa/metabolismo
16.
Biochim Biophys Acta Gen Subj ; 1865(6): 129891, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33689830

RESUMO

BACKGROUND: The epithelium forms a protective barrier against external biological, chemical and physical insults. So far, AFM-based, micro-mechanical measurements have only been performed on single cells and confluent cells, but not yet on cells in mature layers. METHODS: Using a combination of atomic force, fluorescence and confocal microscopy, we determined the changes in stiffness, morphology and actin distribution of human mammary epithelial cells (HMECs) as they transition from single cells to confluency to a mature layer. RESULTS: Single HMECs have a tall, round (planoconvex) morphology, have actin stress fibers at the base, have diffuse cortical actin, and have a stiffness of 1 kPa. Confluent HMECs start to become flatter, basal actin stress fibers start to disappear, and actin accumulates laterally where cells abut. Overall stiffness is still 1 kPa with two-fold higher stiffness in the abutting regions. As HMECs mature and form multilayered structures, cells on apical surfaces become flatter (apically more level), wider, and seven times stiffer (mean, 7 kPa) than single and confluent cells. The main drivers of these changes are actin filaments, as cells show strong actin accumulation in the regions where cells adjoin, and in the apical regions. CONCLUSIONS: HMECs stiffen, flatten and redistribute actin upon transiting from single cells to mature, confluent layers. GENERAL SIGNIFICANCE: Our findings advance the understanding of breast ductal morphogenesis and mechanical homeostasis.


Assuntos
Citoesqueleto de Actina/fisiologia , Células Epiteliais/citologia , Glândulas Mamárias Humanas/citologia , Organogênese , Células Cultivadas , Células Epiteliais/fisiologia , Feminino , Humanos , Glândulas Mamárias Humanas/fisiologia , Microscopia de Força Atômica
17.
Front Immunol ; 12: 621824, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717123

RESUMO

Peripheral T cells capable of discriminating between self and non-self antigens are major components of a robust adaptive immune system. The development of self-tolerant T cells is orchestrated by thymic epithelial cells (TECs), which are localized in the thymic cortex (cortical TECs, cTECs) and medulla (medullary TECs, mTECs). cTECs and mTECs are essential for differentiation, proliferation, and positive and negative selection of thymocytes. Recent advances in single-cell RNA-sequencing technology have revealed a previously unknown degree of TEC heterogeneity, but we still lack a clear picture of the identity of TEC progenitors in the adult thymus. In this review, we describe both earlier and recent findings that shed light on features of these elusive adult progenitors in the context of tissue homeostasis, as well as recovery from stress-induced thymic atrophy.


Assuntos
Células-Tronco Adultas/fisiologia , Autoantígenos/imunologia , Células Epiteliais/fisiologia , Síndromes de Imunodeficiência/imunologia , Linfócitos T/imunologia , Timo/citologia , Animais , Diferenciação Celular , Seleção Clonal Mediada por Antígeno , Humanos , Tolerância Imunológica , Imunidade Celular
18.
J Biosci Bioeng ; 131(6): 679-685, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33678531

RESUMO

Hair regenerative medicine has emerged as a promising treatment strategy for severe hair loss, such as end-stage androgenetic alopecia. Various approaches to engineering three-dimensional tissue grafts have been explored since they drive the ability to regenerate hair follicles when transplanted. In the present study, we demonstrated the assembly of human adipose-derived stem cells (hASCs) into hair follicle germ (HFG)-like aggregates for de novo hair regeneration. We mixed human dermal papilla cells (hDPCs), murine embryonic epithelial cells, and hASCs in suspension, and allowed them to form aggregates. During three days of culture, cells initially formed a single aggregate with a random distribution of the three cell types, but the epithelial and dermal papilla cells subsequently separated from each other and formed a dumbbell-shaped HFG, with hASCs localized on the hDPC aggregate side. The involvement of hASCs significantly increased gene expression associated with hair morphogenesis compared to HFGs without hASCs. The self-organization of the three cell types was observed in our scalable lab-made chip device. HFGs containing hASCs efficiently generated hair shafts upon transplantation to nude mice, while only a few shafts were generated with HFGs without hASCs. This approach may be a promising strategy for fabricating tissue grafts for hair regenerative medicine.


Assuntos
Tecido Adiposo/citologia , Alopecia/terapia , Folículo Piloso/transplante , Células-Tronco/fisiologia , Alopecia/patologia , Animais , Células Cultivadas , Embrião de Mamíferos , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Feminino , Folículo Piloso/citologia , Folículo Piloso/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Gravidez , Regeneração/fisiologia , Medicina Regenerativa/métodos , Células-Tronco/citologia , Engenharia Tecidual/métodos
19.
Aging (Albany NY) ; 13(4): 4747-4777, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33601339

RESUMO

Senescent cells produce chronic inflammation that contributes to the diseases and debilities of aging. How this process is orchestrated in epithelial cells, the origin of human carcinomas, is poorly understood. We used human normal oral keratinocytes (NOKs) to elucidate senescence programs in a prototype primary mucosal epithelial cell that senesces spontaneously. While NOKs exhibit several typical facets of senescence, they also display distinct characteristics. These include expression of p21WAF1/CIP1 at early passages, making this common marker of senescence unreliable in NOKs. Transcriptome analysis by RNA-seq revealed specific commonalities with and differences from cancer cells, explicating the tumor avoidance role of senescence. Repression of DNA repair genes that correlated with downregulation of E2F1 mRNA and protein was observed for two donors; a divergent result was seen for the third. Using proteomic profiling of soluble (non-vesicular) and extracellular vesicle (EV) associated secretions, we propose additions to the senescence associated secretory phenotype, including HSP60, which localizes to the surface of EVs. Finally, EVs from senescent NOKs activate interferon pathway signaling in THP-1 monocytes in a STING-dependent manner and associate with mitochondrial and nuclear DNA. Our results highlight senescence changes in epithelial cells and how they might contribute to chronic inflammation and age-related diseases.


Assuntos
Senescência Celular/fisiologia , Células Epiteliais/fisiologia , Perfilação da Expressão Gênica , Queratinócitos/metabolismo , Mucosa Bucal , Vesículas Extracelulares , Humanos , Análise de Sequência de RNA , Transdução de Sinais
20.
Science ; 371(6531): 839-846, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33602855

RESUMO

Organoid technology holds great promise for regenerative medicine but has not yet been applied to humans. We address this challenge using cholangiocyte organoids in the context of cholangiopathies, which represent a key reason for liver transplantation. Using single-cell RNA sequencing, we show that primary human cholangiocytes display transcriptional diversity that is lost in organoid culture. However, cholangiocyte organoids remain plastic and resume their in vivo signatures when transplanted back in the biliary tree. We then utilize a model of cell engraftment in human livers undergoing ex vivo normothermic perfusion to demonstrate that this property allows extrahepatic organoids to repair human intrahepatic ducts after transplantation. Our results provide proof of principle that cholangiocyte organoids can be used to repair human biliary epithelium.


Assuntos
Doenças dos Ductos Biliares/terapia , Ductos Biliares Intra-Hepáticos/fisiologia , Ductos Biliares/citologia , Terapia Baseada em Transplante de Células e Tecidos , Células Epiteliais/citologia , Organoides/transplante , Animais , Bile , Ductos Biliares/fisiologia , Ductos Biliares Intra-Hepáticos/citologia , Ducto Colédoco/citologia , Células Epiteliais/fisiologia , Vesícula Biliar/citologia , Regulação da Expressão Gênica , Humanos , Fígado/fisiologia , Transplante de Fígado , Transplante de Células-Tronco Mesenquimais , Camundongos , Organoides/fisiologia , RNA-Seq , Obtenção de Tecidos e Órgãos , Transcriptoma
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