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1.
Toxicol Lett ; 316: 109-118, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472180

RESUMO

Lithocholic acid (LCA) is both a secondary bile acid and a vitamin D receptor (VDR) ligand. The VDR is activated by 1,25-dihydroxy vitamin D3 and plays an important role in maintaining integrity of the intestinal mucosal barrier. LCA can also substitute for vitamin D to carry out the in vivo functions of vitamin D. However, it is unclear whether activation of the VDR by LCA affects mucosal barrier function. In the present study, we researched the protective effect of LCA on tumor necrosis factor-alpha (TNF-α)-induced intestinal epithelial barrier dysfunction in Caco-2 cells of the human epithelial intestinal adenocarcinoma cell line. Caco-2 cell monolayers were pretreated with LCA and then exposed to 100 ng/mL TNF-α. The results showed that LCA alleviated the decrease in transepithelial electrical resistance and the increase in FITC-Dextran flux induced by TNF-α. LCA ameliorated the TNF-α-induced decrease in protein expression and distribution of ZO-1, E-cadherin, Occludin, and Claudin-1, which are tight junction markers. Additionally, the LCA treatment effectively counteracted TNF-α-mediated downregulation of silent information regulator 1 (SIRT1), nuclear factor erythroid2-related factor 2 (Nrf2), and heme oxygenase-1, which are related to oxidative stress. Increases in NF-κB p-p65 and p-IκB-α induced by TNF-α were significantly inhibited by LCA. Considering all these, the present study indicates that LCA has a significant protective effect on TNF-α-induced injury of intestinal barrier function through the VDR and suggests that suppressing NF-κB signaling and activating the SIRT1/Nrf2 pathway might be one of the mechanisms underlying the protective effect of LCA.


Assuntos
Células Epiteliais/efeitos dos fármacos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Ácido Litocólico/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Receptores de Calcitriol/agonistas , Sirtuína 1/metabolismo , Fator de Necrose Tumoral alfa/toxicidade , Células CACO-2 , Citoproteção , Impedância Elétrica , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Permeabilidade , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia
2.
Toxicol Lett ; 316: 119-126, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31539570

RESUMO

In vivo experiments are still widely used for the testing of lung toxicity but there is an ethical and legal obligation to replace, reduce and refine animal testing. Lung A549 cells could serve as an in vitro indicator for acute lung toxicity but little data about the correlation of the cytotoxicity in A549 cells and data leading to CLP classifications are available. We exposed A549 cells to 19 CLP-classified substances with doses of 25, 50, and 100 µg/cm2 either under submerged (SME) condition or with aerosols at the air-liquid interface (ALIF) and determined accuracy, precision, sensitivity and the F1 score with the CLP classifications H330, H332, or H335. When data from both exposure methods were combined, we found accuracies of 0.84 ±â€¯0.05, precisions of 0.74 ±â€¯0.1, sensitivities of 0.93 ±â€¯0.08 and F1 scores of 0.82 ±â€¯0.04. Separated from each other, ALIF exposure was more sensitive at any dose but, at higher doses, also less accurate and precise compared to SME. Considering the 19 substances tested, our data suggest that cytotoxicity in A549 cells could be a reliable in vitro indicator for in vivo toxicity. Thus, we discuss how A549 could be integrated into validation test guidelines.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Alternativas aos Testes com Animais/métodos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Neoplasias Pulmonares/patologia , Material Particulado/toxicidade , Células A549 , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Camundongos , Tamanho da Partícula , Pós , Reprodutibilidade dos Testes , Medição de Risco
3.
Adv Exp Med Biol ; 1165: 233-252, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31399968

RESUMO

The renal tubules are the major component of the kidney and are vulnerable to a variety of injuries including ischemia, proteinuria, toxins, and metabolic disorders. It has long been believed that tubules are the victim of injury. In this review, we shift this concept to renal tubules as a driving force in the progression of kidney disease. In response to injury, tubular epithelial cells (TECs) can synthesize and secrete varieties of bioactive molecules that drive interstitial inflammation and fibrosis. Innate immune-sensing receptors on the TECs also aggravate immune responses. Necroinflammation, an auto-amplification loop between tubular cell death and interstitial inflammation, leads to the exacerbation of renal injury. Furthermore, TECs also play an active role in progressive renal injury via mechanisms associated with the conversion into collagen-producing fibroblast phenotype, cell cycle arrest at both G1/S and G2/M checkpoints, and metabolic disorder. Thus, a better understanding the mechanisms by which tubular injury drives AKI and CKD is necessary for the development of therapeutics to halt the progression of CKD.


Assuntos
Células Epiteliais/patologia , Nefropatias/fisiopatologia , Túbulos Renais/citologia , Pontos de Checagem do Ciclo Celular , Fibrose , Humanos , Imunidade Inata , Rim/patologia
4.
Anticancer Res ; 39(8): 4561-4568, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366560

RESUMO

BACKGROUND/AIM: Neoplastic spindle cells (NSCs) are believed to play a role in cancer invasion and metastasis, as well as in poor prognosis. The clinicopathological characteristics and prognostic relevance of NSCs was investigated in gallbladder cancer. MATERIALS AND METHODS: Specimens were obtained from 62 patients with gallbladder cancer who underwent surgery. The emergence of NSCs and their correlation with clinicopathological factors, prognosis, and EMT markers was evaluated. RESULTS: The NSC grade correlated with tumor size, preoperative CA19-9, surgical margin, the degree of differentiation, the depth of invasion, lymph node metastasis, lymphatic invasion, vascular invasion, and perineural invasion. Multivariate analysis of overall survival showed that NSCs were an independent prognostic factor. A correlation between NSCs and EMT was also suggested. CONCLUSION: NSCs are an independent prognostic factor for patients with postoperative gallbladder cancer, which also suggests a correlation between NSCs and EMT.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Vesícula Biliar/patologia , Invasividade Neoplásica/patologia , Prognóstico , Adulto , Idoso , Antígeno CA-19-9/sangue , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Neoplasias da Vesícula Biliar/sangue , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Invasividade Neoplásica/genética
5.
Acta Cir Bras ; 34(6): e201900602, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31432993

RESUMO

PURPOSE: To investigate the role and related mechanisms of miR-106a in sepsis-induced AKI. METHODS: Serum from sepsis and healthy patients was collected, sepsis mouse model was established by cecal ligation and puncture (CLP). TCMK-1 cells were treated with lipopolysaccharide (LPS) and transfected with THBS2-small interfering RNA (siTHBS2), miR-106a inhibitor, miR-106a mimics and their negative controls (NCs). The expression of miR-106a, thrombospondin 2 (THBS2), Bax, cleaved caspase-3 and Bcl-2, cell viability, relative caspase-3 activity and TNF-α, IL-1ß, IL-6 content were respectively detected by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, Cell Counting Kit-8 (CCK-8) and enzyme linked immunosorbent assay (ELISA). The relationship between miR-106a and THBS2 was confirmed by dual luciferase reporter assay. RESULTS: MiR-106a was up-regulated in serum of sepsis patients, CLP-induced mice models and LPS-induced TCMK-1 cells. LPS reduced cell viability and Bcl-2 expression, and increased caspase-3 activity, Bax expression, the content of TNF-α, IL-1ß, IL-6. THBS2 was a target of miR-106a. The decreases of caspase-3 activity, TNF-α, IL-1ß, IL-6, Bax expression and the increases of cell viability, Bcl-2 expression caused by miR-106a knockdown were reversed when THBS2 silencing in LPS-stimulated TCMK-1 cells. CONCLUSION: MiR-106a aggravated LPS-induced inflammation and apoptosis of TCMK-1 cells via regulating THBS2 expression.


Assuntos
Lesão Renal Aguda/metabolismo , Células Epiteliais/patologia , Rim/citologia , MicroRNAs/metabolismo , Sepse/patologia , Trombospondinas/farmacologia , Lesão Renal Aguda/patologia , Adulto , Animais , Apoptose , Estudos de Casos e Controles , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Sepse/metabolismo , Transfecção
6.
Cancer Immunol Immunother ; 68(9): 1443-1454, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31444607

RESUMO

Immunotherapy is effective in head and neck squamous cell carcinoma (HNSCC), but only a minority of patients responds to immune checkpoint blockade (ICB). To contribute to a better understanding of the underlying immune biology, we combined histomorphological evaluation and molecular analysis of the HNSCC immune microenvironment in the TCGA cohort. Analyzing digital HE-stained slides, a method for classification of tumor infiltrating lymphocytes (TILs) in the intra-epithelial compartment (ieTILs, present vs. absent) and the stromal compartment (strTILs, high vs. low) was established. We also analyzed the abundance of eight immune cell populations (estimated from RNAseq data) and PD-L1 mRNA expression. Status of ieTILs and status of strTILs were concordant for 61%, but discordant for 39% of tumors. In univariate survival analysis, ieTILs were a positive prognostic marker for DFS in the study cohort (HR = 0.66, p = 0.015) and in the HPV- subcohort (HR = 0.68, p = 0.04), but not in the HPV + subcohort. T cells were a positive prognostic marker for DFS in the study cohort (HR = 0.80, p = 0.03) and in the HPV + subcohort (HR = 0.20, p = 0.001), but not in the HPV- subcohort. In univariate survival analysis, PD-L1 mRNA expression was neither associated with DFS nor with OS. However, in bivariate and multivariate analyses including both PD-L1 mRNA levels and T cells, PD-L1 was a negative prognostic marker of DFS and OS, while T cells remained a positive prognostic marker. In conclusion, ieTILs and strTILs were non-redundant biomarkers in HNSCC and should be evaluated separately. The identified prognostic markers should be evaluated for predictivity in ICB-treated patients.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/imunologia , Células Epiteliais/patologia , Neoplasias de Cabeça e Pescoço/imunologia , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/imunologia , Células Estromais/patologia , Antígeno B7-H1/genética , Biomarcadores Tumorais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/mortalidade , Estudos de Coortes , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sequência de RNA , Análise de Sobrevida , Resultado do Tratamento , Microambiente Tumoral
7.
Toxicol Lett ; 314: 43-52, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31310794

RESUMO

Thioredoxin is an evolutionarily conserved antioxidant protein that plays a crucial role for fundamental cellular processes and embryonic development. Growing evidence support that Thioredoxin influences cellular response to chemicals insults, particularly those accompanying oxidative stress. The mechanisms underlying the functions of Thioredoxin1 in the embryonic development under the environmental toxicant exposure remain, however, largely unexplored. We report here that thioredoxin1 becomes differentially expressed in zebrafish embryos after exposure to 9 out of 11 environmental chemicals. In situ gene expression analysis show that thioredoxin1 is expressed in neurons, olfactory epithelia, liver and swim bladder under normal conditions. After MeHg exposure, however, thioredoxin1 is ectopically induced in the hair cells of the lateral line and in epithelia cells of the pharynx. Knockdown of Thioredoxin1 induces hydrocephalus and increases cell apoptosis in the brain ventricular epithelia cells. In comparison with 5% malformation in embryos injected with control morpholino, MeHg induces more than 77% defects in Thioredoxin1 knockdown embryos. Our data suggest that there is an association between hydrocephalus and Thioredoxin1 malfunction in embryonic development, and provide valuable information to elucidate the protective role of Thioredoxin1 against chemicals disruption.


Assuntos
Encéfalo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Hidrocefalia/induzido quimicamente , Tiorredoxinas/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Apoptose/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica no Desenvolvimento , Hidrocefalia/embriologia , Hidrocefalia/genética , Hidrocefalia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Tiorredoxinas/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
8.
Toxicol Lett ; 313: 150-158, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276768

RESUMO

Ochratoxin A (OTA), one of the most abundant food-contaminating mycotoxins, is a possible carcinogen to humans. We previously demonstrated that long-term (40 weeks) OTA exposure induces the malignant transformation of human gastric epithelium cells (GES-1) in vitro. However, the specific mechanism underlying OTA-induced gastric carcinogenesis is complex. In the present study, we used 2-DE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI/TOF MS) combined with bioinformatics and immunoblotting to investigate the differentially expressed proteins between GES-1 and OTA-malignant transformed GES-1 cells (OTA-GES-1T cells) in vitro. We found that four differentially expressed proteins were identified after malignant transformation, including actin, cytoplasmic 1 (ACTB), F-actin-capping protein subunit alpha-1 (CAPZA1), Annexin A3 (ANXA3), thioredoxin peroxidase B from red blood cells (TPx-B) and Fibrinogen beta B (Fibrinogen ß). Among the differentially expressed proteins, the effect of Annexin A3 was analyzed by MTT assay, western blot, cell cycle analysis, wound healing assay, Transwell assay, and colony formation assay in OTA-GES-1T cells. The results showed that inhibition of Annexin A3 by siRNA effectively prevented the proliferation, migration, and invasion abilities of OTA-GES-1T cells. Collectively, the results of this study will guide future research on OTA carcinogenicity.


Assuntos
Anexina A3/metabolismo , Carcinógenos/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Células Epiteliais/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Ocratoxinas/toxicidade , Neoplasias Gástricas/induzido quimicamente , Anexina A3/genética , Western Blotting , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Biologia Computacional , Eletroforese em Gel Bidimensional , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Invasividade Neoplásica , Proteômica/métodos , Transdução de Sinais/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
9.
Gastroenterology ; 157(4): 1093-1108.e11, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325428

RESUMO

BACKGROUND & AIMS: Inflammation, injury, and infection up-regulate expression of the tryptophan metabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) in the intestinal epithelium. We studied the effects of cell-specific IDO1 expression in the epithelium at baseline and during intestinal inflammation in mice. METHODS: We generated transgenic mice that overexpress fluorescence-tagged IDO1 in the intestinal epithelium under control of the villin promoter (IDO1-TG). We generated intestinal epithelial spheroids from mice with full-length Ido1 (controls), disruption of Ido1 (knockout mice), and IDO1-TG and analyzed them for stem cell and differentiation markers by real-time polymerase chain reaction, immunoblotting, and immunofluorescence. Some mice were gavaged with enteropathogenic Escherichia coli (E2348/69) to induce infectious ileitis, and ileum contents were quantified by polymerase chain reaction. Separate sets of mice were given dextran sodium sulfate or 2,4,6-trinitrobenzenesulfonic acid to induce colitis; intestinal tissues were analyzed by histology. We utilized published data sets GSE75214 and GDS2642 of RNA expression data from ilea of healthy individuals undergoing screening colonoscopies (controls) and patients with Crohn's disease. RESULTS: Histologic analysis of small intestine tissues from IDO1-TG mice revealed increases in secretory cells. Enteroids derived from IDO1-TG intestine had increased markers of stem, goblet, Paneth, enteroendocrine, and tuft cells, compared with control enteroids, with a concomitant decrease in markers of absorptive cells. IDO1 interacted non-enzymatically with the aryl hydrocarbon receptor to inhibit activation of NOTCH1. Intestinal mucus layers from IDO1-TG mice were 2-fold thicker than mucus layers from control mice, with increased proportions of Akkermansia muciniphila and Mucispirillum schaedleri. Compared to controls, IDO1-TG mice demonstrated an 85% reduction in ileal bacteria (P = .03) when challenged with enteropathogenic E coli, and were protected from immune infiltration, crypt dropout, and ulcers following administration of dextran sodium sulfate or 2,4,6-trinitrobenzenesulfonic acid. In ilea of Crohn's disease patients, increased expression of IDO1 correlated with increased levels of MUC2, LYZ1, and aryl hydrocarbon receptor, but reduced levels of SLC2A5. CONCLUSIONS: In mice, expression of IDO1 in the intestinal epithelial promotes secretory cell differentiation and mucus production; levels of IDO1 are positively correlated with secretory cell markers in ilea of healthy individuals and Crohn's disease patients. We propose that IDO1 contributes to intestinal homeostasis.


Assuntos
Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Microbioma Gastrointestinal , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Doenças Inflamatórias Intestinais/enzimologia , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/enzimologia , Mucosa Intestinal/microbiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores Notch/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Estudos de Casos e Controles , Linhagem Celular , Linhagem da Célula , Modelos Animais de Doenças , Células Epiteliais/enzimologia , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Genótipo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Camundongos Knockout , Fenótipo , Receptores de Hidrocarboneto Arílico/genética , Receptores Notch/genética , Via Secretória , Transdução de Sinais , Células-Tronco/enzimologia , Células-Tronco/microbiologia , Células-Tronco/patologia
10.
Histochem Cell Biol ; 152(3): 195-206, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31179519

RESUMO

Desmosomal cadherins, desmocollins, and desmogleins are cholesterol-dependent entities responsible for the stable adhesion of desmosomes in epithelial cells. Here, we investigated the influence of cellular cholesterol depletion on the dynamic properties of the desmosomal cadherin desmocollin, particularly the lateral mobility and distribution of desmocollin 2 (Dsc2-YFP) in the plasma membrane, and how these properties influence the adhesion strength of desmosomes. Depletion of cellular cholesterol decreased the lateral mobility of Dsc2-YFP and caused dispersion of Dsc2-YFP in the plasma membrane of epithelial MDCK cells. As a consequence of the altered Dsc2-YFP dynamics, the adhesive strength of desmosomes was weakened. Moreover, our study is the first to show and quantify the co-association of desmosomes with cholesterol/sphingomyelin-enriched membrane domains at the ultrastructural level. Taken together, our data emphasize a critical role for the cellular cholesterol content in regulating the lateral mobility and distribution of Dsc2 and show that cholesterol depletion reduces the strength of desmosomal adhesions.


Assuntos
Colesterol/metabolismo , Caderinas de Desmossomos/metabolismo , Desmossomos/metabolismo , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Colesterol/deficiência , Cães , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Madin Darby de Rim Canino
11.
Dokl Biochem Biophys ; 485(1): 150-152, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31201638

RESUMO

A hybrid 6XRE-hTERT promoter consisting of the hTERT tumor-specific promoter and six copies of the XRE element from the CYP1A1 human gene promoter was created. Using a human lung cancer cells as a model, we showed that XRE elements in the hybrid promoter greatly increase the activity of the hTERT promoter and ensure the reporter gene transcriptional activation in response to the treatment of the cells with the AhR ligand benzo(a)pyrene. However, similar effects were also observed in normal human bronchial epithelial cells HBEpC, which indicates the loss of the tumor-specific activity by the 6XRE-hTERT hybrid promoter. XRE elements can be used for nonspecific transcription enhancement but are unsuitable for the creation of tumor-specific promoters with enhanced activity.


Assuntos
Citocromo P-450 CYP1A1 , Elementos de Resposta , Telomerase , Ativação Transcricional/efeitos dos fármacos , Células A549 , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Benzo(a)pireno/toxicidade , Brônquios/metabolismo , Brônquios/patologia , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1A1/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Telomerase/biossíntese , Telomerase/genética
12.
Chem Biol Interact ; 310: 108711, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207224

RESUMO

Gastrointestinal infections are considered a serious public health problem in view of their high incidence and the increasing antibiotic resistance of the microorganisms involved in their pathogenesis, namely Escherichia coli. Consequently, finding new ways to prevent and/or threat these infections is urgent. In this study we investigated whether a well-characterised polyphenolic red wine extract is able to inhibit the cytotoxic effects induced by a clinical pathogenic Escherichia coli strain (E. coli 270) against HT-29 colon epithelial cells. Firstly, we provide evidences showing that the E. coli strain triggered the death of the intestinal epithelial cells through the production and release of a toxin. Then we support that, in a concentration dependent way, RWE through both, a direct interaction with bacterial exotoxin and the epithelial cells, prevented the action of the toxin on the cells, significantly reducing cell death. This intends to constitute a position paper as detailed mechanisms for the inhibition of E. coli-induced toxicity by polyphenols are yet to be completely unraveled. However, considering that the amount of red wine polyphenols used can be easily achieved in a normal diet, this study suggests that RWE may provide a readily available dietary product with potential benefit for the prevention and/or treatment of intestinal infections induced by intestinal pathogenic bacteria and may open new therapeutic avenues for the development of potential natural antimicrobial agents.


Assuntos
Infecções por Escherichia coli/prevenção & controle , Gastroenteropatias/prevenção & controle , Polifenóis/uso terapêutico , Vinho , Morte Celular/efeitos dos fármacos , Células Epiteliais/patologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Infecções por Escherichia coli/tratamento farmacológico , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/microbiologia , Células HT29 , Humanos , Polifenóis/farmacologia
13.
Mol Carcinog ; 58(8): 1427-1437, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31162747

RESUMO

The Helicobacter pylori (H. pylori) cytotoxin-associated gene A (CagA) and Krüppel-like transcription factor (KLF4) were both closely associated with the development and progression of gastric cancer (GC). However, the nature of the interactions between CagA and KLF4 in GC development has not been elucidated. Therefore, we focused on the CagA-mediated promotion of the malignant transformation of gastric epithelial cells. Herein, we first examined the expression of KLF4 in both human cancer and paracarcinoma tissues with or without H. pylori infection and found that KLF4 expression was significantly decreased in H. pylori-positive GC cells compared with the H. pylori-negative GC cells. Further functional studies revealed that the increased expression of CagA could suppress KLF4 expression and promote the malignant transformation of normal epithelial cells. Subsequently, we found that CagA could upregulate miR-155 and further restrict the expression of downstream KLF4. More importantly, the overexpression of miR-155 in GES-1 promoted epithelial-mesenchymal transition and eventually facilitated tumor growth in vivo. Overall, the identification of the CagA/miR-155/KLF4 signaling pathway provided a new insight into the development and treatment of GC.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Transformação Celular Neoplásica/patologia , Mucosa Gástrica/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Gástricas/patologia , Adulto , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/genética , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Mucosa Gástrica/citologia , Células HEK293 , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , MicroRNAs/metabolismo , Transplante de Neoplasias , Transdução de Sinais , Estômago/patologia , Neoplasias Gástricas/genética , Transplante Heterólogo
14.
Environ Pollut ; 252(Pt A): 879-887, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203115

RESUMO

Deoxynivalenol (DON), a fungus-derived mycotoxin, also known as vomitoxin, is found in a wide range of cereal grains and grain-based food products. The biological toxicity of DON has been described in various species, but its toxicity and functional effects in mammary epithelial cells are unclear. In this study, we investigated the effect of DON on bovine mammary epithelial (MAC-T) cells using mechanistic approaches. We detected DON-induced cell cycle abrogation and calcium deficiency, leading to apoptotic cell death via MAPK signaling pathways. Moreover, we studied the transcriptional activation of blood and milk junctional regulators as well as inflammatory cytokines in response to DON. The results of this study contribute to a comprehensive understanding of DON-associated toxicity mechanisms in bovine mammary epithelial cells, which may facilitate the enhancement of milk stabilization in parallel with the establishment of safety profiles to protect against DON contamination in livestock farms and in the food industry.


Assuntos
Apoptose/efeitos dos fármacos , Grão Comestível/química , Células Epiteliais/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Micotoxinas/toxicidade , Tricotecenos/toxicidade , Animais , Bovinos , Contagem de Células , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Homeostase , Glândulas Mamárias Animais/citologia , Leite
15.
Oxid Med Cell Longev ; 2019: 1503478, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049125

RESUMO

When dairy cows are exposed to high-temperature environment, their antioxidant capacity and productive performance decrease, leading to economic losses. Emerging evidence has shown that selenium (Se) can effectively alleviate heat stress in dairy cows; however, the cellular mechanism underlying this protection is not clear. The purpose of this study was to investigate and compare the protective effects of inorganic Se (sodium selenite, SS) and organic Se (selenite methionine, SM) in MAC-T (mammary alveolar cells-large T antigen, a bovine mammary epithelial cell (BMEC) line) cells during heat stress. MAC-T cells were treated in 4 ways unless otherwise described: (i) cells in the heat treatment (HT) group were cultured at 42.5°C for 1 h and then recovered in 37°C for another 12 h; (ii) the SM group was pretreated with organic Se for 2 h, cultured at 42.5°C for 1 h, and then recovered in 37°C for 12 h; (iii) the SS group was treated similarly to the SM group except that the cells were pretreated with inorganic Se instead of organic Se; and (iv) the control group was continuously cultured in 37°C and received no Se treatment. The results showed that heat shock at 42.5°C for 1 h triggered heat shock response, sabotaged the redox balance, and reduced cell viability in MAC-T cells; and pretreatment of cells with SM or SS effectively alleviated the negative effects of heat shock on the cells. However, the cells were much more sensitive to SS treatment but more tolerant to SM. In addition, two forms of Se appeared to affect the expression of different genes, including nuclear factor erythroid 2-related factor 2 (Nrf2) and inducible nitric oxide synthase (iNOS) in the SM group and thioredoxin reductase 1 (TXNRD1) in the SS group in Nrf2-ARE (antioxidant response element) antioxidant pathway and inflammation response. In summary, results showed the mechanistic differences in the protective effects of organic and inorganic Se on heat stress in BMECs.


Assuntos
Antioxidantes/farmacologia , Células Epiteliais/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Selênio/farmacologia , Selenito de Sódio/farmacologia , Animais , Bovinos , Linhagem Celular , Células Epiteliais/patologia , Feminino , Glândulas Mamárias Animais/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Tiorredoxina Redutase 1/metabolismo
16.
Biomed Res Int ; 2019: 3638469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31058187

RESUMO

Eosinophil asthma is characterized by the infiltration of eosinophils to the bronchial epithelium. The toxic cationic protein released by eosinophils, mainly major basic protein (MBP), is one of the most important causative factors of epithelium damage. Poly-L-Arginine (PLA) is a kind of synthetic cationic polypeptides, which is widely used to mimic the effects of MBP on epithelial cells in vitro. However, little is known about the changes of differentially expressed genes (DEGs) and transcriptome profiles in cationic protein stimulated epithelial cells. In this study, we compared the expression of DEGs and transcriptome profiles between PLA-treated airway epithelial cells NCI-H292 and control. The results showed that there were a total of 230 DEGs, of which 86 were upregulated and 144 were downregulated. These DEGs were further analyzed using gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The results showed that the upregulated DEGs were involved in cholesterol synthesis, protein binding, and composition of cellular membranes, mainly enriched in metabolic and biosynthesis pathways. While downregulated DEGs were implicated in cell adhesion, extracellular matrix (ECM) composition and cytoskeleton and were enriched in ECM pathway. In conclusion, our research provided the mechanism of the cationic polypeptides acting on the airway epithelial cells on the basis of transcriptomic profile, and this could be regarded as important indications in unveiling the pathologic role of natural cationic proteins in the damage to epithelial cells of asthmatics.


Assuntos
Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Pulmão/metabolismo , Transcriptoma/genética , Cátions/farmacologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Colesterol/genética , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/genética , Redes Reguladoras de Genes/genética , Humanos , Pulmão/efeitos dos fármacos , Peptídeos/farmacologia , Sequenciamento Completo do Exoma
17.
Gastroenterology ; 157(2): 349-364.e1, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31082367

RESUMO

In patients with Barrett's esophagus (BE), metaplastic columnar mucosa containing epithelial cells with gastric and intestinal features replaces esophageal squamous mucosa damaged by gastroesophageal reflux disease. This condition is estimated to affect 5.6% of adults in the United States, and is a major risk factor for esophageal adenocarcinoma. Despite the prevalence and importance of BE, its pathogenesis is incompletely understood and there are disagreements over the cells of origin. We review mechanisms of BE pathogenesis, including transdifferentiation and transcommitment, and discuss potential cells of origin, including basal cells of the squamous epithelium, cells of esophageal submucosal glands and their ducts, cells of the proximal stomach, and specialized populations of cells at the esophagogastric junction (residual embryonic cells and transitional basal cells). We discuss the concept of metaplasia as a wound-healing response, and how cardiac mucosa might be the precursor of the intestinal metaplasia of BE. Finally, we discuss shortcomings in current diagnostic criteria for BE that have important clinical implications.


Assuntos
Esôfago de Barrett/patologia , Células Epiteliais/patologia , Mucosa Esofágica/patologia , Adenocarcinoma/patologia , Adenocarcinoma/prevenção & controle , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/epidemiologia , Cárdia/citologia , Cárdia/patologia , Transdiferenciação Celular , Progressão da Doença , Mucosa Esofágica/citologia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/prevenção & controle , Junção Esofagogástrica/citologia , Junção Esofagogástrica/patologia , Mucosa Gástrica/citologia , Mucosa Gástrica/patologia , Humanos , Metaplasia/patologia , Estados Unidos , Cicatrização/fisiologia
18.
Acta Histochem ; 121(5): 595-603, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31109687

RESUMO

Due to the broad toxic relevance of acrylamide, many measures have been taken since the 1900s. These measures increased day by day when acrylamide was discovered in foods in 2002, and its toxic spectrum was found to be wider than expected. Therefore, in some countries, the products with higher acrylamide content were restricted. On the other hand, the effects of acrylamide on the respiratory system cells have yet to be well understood. In this study, we aimed at investigating the effect of acrylamide on lung epithelial BEAS-2B cells. Initially, the cytotoxic effect of acrylamide on BEAS-2B was determined by MTT assay. Then, cellular oxidative stress was measured. Flow cytometry analysis was conducted for Annexin-V and caspase 3/7. Furthermore, Bax, Bcl-2 and Nrf-2 proteins were evaluated by immunocytochemistry. Finally, acrylamide-induced cellular morphological changes were observed under confocal and TEM microscopes. According to MTT results, the IC50 concentration of acrylamide was 2.00 mM. After acrylamide treatment, oxidative stress increased dose-dependently. Annexin V-labelled apoptotic cells and caspase 3/7 activity were higher than untreated cells in acrylamide-treated cells. Immunocytochemical examination revealed a marked decrease in Bcl-2, an increase in Bax and Nrf-2 protein staining upon acrylamide treatment. Furthermore, in confocal and TEM microscopy, apoptotic hallmarks were pronounced. In the present study, acrylamide was suggested to display anti-proliferative activity, decrease viability, induce apoptosis and oxidative stress and cause morphological changes in BEAS-2B cells.


Assuntos
Acrilamida/toxicidade , Apoptose/efeitos dos fármacos , Citotoxinas/toxicidade , Pulmão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/ultraestrutura , Humanos , Pulmão/patologia , Pulmão/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Transmissão
19.
J Exp Clin Cancer Res ; 38(1): 190, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072360

RESUMO

BACKGROUND: One of the most potent costimulatory molecules involved in the recognition and killing of tumor cells is CD80. However, its role and the molecular mechanisms regulating its expression in sporadic colorectal carcinogenesis remain elusive. Here, we provide evidence for CD80 overexpression in human colon epithelial cells derived from preneoplastic mucosa. METHODS: Expression of CD80 on colonic epithelial cells isolated from normal human colonic mucosa, preneoplastic and neoplastic specimens was assessed by flow cytometry. WT and CD80KO mice received azoxymethane to induce colon preneoplastic lesions and sacrificed to perform histology, flow cytometry analysis and immunohistochemistry of colonic mucosa. Some WT mice were treated with a monoclonal anti-CD80 antibody following AOM administration. Primary colon epithelial cells and CT26 cell line were used to quantify the expression of CD80 in response to pro-oxidant stimuli. Specific pharmacological inhibitors and siRNA silencing were used to inhibit MAPK pathways and STAT3. RESULTS: CD80 expression was significantly increased in colon epithelial cells of human preneoplastic lesions. In the AOM model, CD80 impairment by administration of neutralizing antibodies or use of CD80 knockout mice enhanced dysplasia development. In vitro, CD80 upregulation was induced by oxidative stress in colon cancer cells and primary colon epithelial cells. In addition, reactive oxygen species could induce CD80 expression via the JNK and p38 MAPK pathways, that activated STAT3 transcription factor in colon cancer epithelial cells. CONCLUSION: This study provide evidence for a major role of CD80 in orchestrating immune surveillance of colon preneoplastic lesions and might help to develop novel approaches that exploit anti-tumor immunity to prevent and control colon cancer.


Assuntos
Antígeno B7-1/genética , Neoplasias do Colo/genética , Lesões Pré-Cancerosas/genética , Fator de Transcrição STAT3/genética , Animais , Antígeno B7-1/imunologia , Carcinogênese/genética , Carcinogênese/imunologia , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Imunofenotipagem/métodos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Estresse Oxidativo/genética , Lesões Pré-Cancerosas/imunologia , Lesões Pré-Cancerosas/patologia , Cultura Primária de Células , Transdução de Sinais/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética
20.
Nat Commun ; 10(1): 2225, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31110179

RESUMO

The effective prevention of tumor initiation, especially for potentially inoperable tumors, will be beneficial to obtain an overall higher quality of our health and life. Hence, thorough understanding of the pathophysiological mechanisms of early tumor formation arising from identifiable cellular origins is required to develop efficient preventative and early treatment options for each tumor type. Here, using genetically engineered mouse models, we provide preclinical experimental evidence for a long-standing open question regarding the pathophysiological potential of a microenvironmental and physiological stressor in tumor development, gastric acid-mediated regional microscopic injury in foregut squamous epithelia. This study demonstrates the association of gastric acid stress with Cyclooxygenase-2-dependent tumor formation originating from tumor-competent Krt5+/Krt15+ foregut basal progenitor cells. Our findings suggest that clinical management of microenvironmental stressor-mediated microscopic injury may be important in delaying tumor initiation from foregut basal progenitor cells expressing pre-existing tumorigenic mutation(s) and genetic alteration(s).


Assuntos
Carcinogênese/patologia , Ciclo-Oxigenase 2/metabolismo , Ácido Gástrico/metabolismo , Neoplasias Gastrointestinais/patologia , Células-Tronco/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Sistema Digestório/patologia , Células Epiteliais/patologia , Epitélio/patologia , Neoplasias Gastrointestinais/etiologia , Queratina-15/genética , Queratina-15/metabolismo , Queratina-5/genética , Queratina-5/metabolismo , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/etiologia , Neoplasias Experimentais/patologia , Inibidores da Bomba de Prótons/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Microambiente Tumoral
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