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2.
Life Sci ; 240: 117089, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759038

RESUMO

AIMS: Gut microbiota has been closely linked to the mucosal immune and been regarded as a reliable target for intestinal inflammation. This study aimed to explore the therapeutic roles of probiotic mixtures of Bifidobacterium infantis, Lactobacillus acidophilus, Enterococcus faecalis with (quadruple probiotics, P-qua) or without (triple probiotics, P-tri) aerobic Bacillus cereus in colitis, focusing on the multiple barrier functions. MATERIALS AND METHODS: Chronic colitis was induced by dextran sulfate sodium (DSS) in C57BL/6 mice. The probiotic mixtures P-qua or P-tri was gavage administrated respectively, while fecal microbiota transplantation (FMT) as a positive control. The intestinal inflammation and functions of multiple barriers were assessed, including the mucus barrier, epithelial barrier and endothelial barrier known as gut-vascular barrier (GVB). Altered composition and diversity in gut microbiota were observed via sequencing analysis. KEY FINDINGS: Both P-qua and P-tri relieved the intestinal inflammation and improved the functions of multiple barriers with increased integrity of mucous layer, enhanced transepithelial electrical resistance, declined epithelial and endothelial permeability to macromolecules in DSS-colitis. Aerobe-contained P-qua revealed a more active role in barrier recovering relative to P-tri, while FMT as a positive control seemed to get better results than pure probiotics. Indeed, P-qua was effective in rebuilding the structure and diversity of gut flora in DSS-colitis, especially increased abundance of Bifidobacterium, Akkermansia, Lactobacillus and Bacteroides. SIGNIFICANCE: Aerobe-contained P-qua was a powerful adjuvant therapy for chronic colitis, via restoring the intestinal microflora and recovering the multi-barriers in the inflamed gut.


Assuntos
Bactérias Aeróbias , Colite/induzido quimicamente , Colite/tratamento farmacológico , Probióticos/uso terapêutico , Animais , Permeabilidade da Membrana Celular , Doença Crônica , Colite/patologia , Sulfato de Dextrana , Transplante de Microbiota Fecal , Fezes/microbiologia , Microbioma Gastrointestinal , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/administração & dosagem , Junções Íntimas
3.
Life Sci ; 241: 117164, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31838135

RESUMO

AIMS: This study was to assess whether andrographolide derivative (AL-1) could restore mucosal homeostasis and regulate tight junctions through MLCK-dependent pathway in DSS-induced colitis mice. MAIN METHODS: Colitis mice model was induced by daily administration of 2.5% DSS for seven days. The therapeutic effect was determined by evaluating the histopathological changes and the pro-inflammatory cytokine level. In addition, the effects of AL-1 on tight junctions were examined by immunohistochemistry and Western blot. The expressions of factors in MLCK-dependent pathway were evaluated by immunofluorescence and Western blot. KEY FINDINGS: AL-1 protected the intestinal barrier function in DSS-induced colitis mice. These protective effects were achieved by maintaining the normal mucus secretion and preserving tight junctions via suppression of the MLCK-dependent pathway. SIGNIFICANCE: AL-1 could prevent the increase in the DSS-induced intestinal permeability. These data indicated that AL-1 could be a promising agent for UC treatment.


Assuntos
Anti-Inflamatórios/farmacologia , Permeabilidade da Membrana Celular/fisiologia , Colite/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Diterpenos/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Animais , Anti-Inflamatórios/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Diterpenos/química , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinase de Cadeia Leve de Miosina/metabolismo , Fosforilação , Transdução de Sinais , Junções Íntimas/metabolismo , Junções Íntimas/patologia
4.
J Enzyme Inhib Med Chem ; 35(1): 1-20, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31619080

RESUMO

Inflammatory bowel disease (IBD) is a chronic immuno-inflammation in gastrointestinal tract. We have evaluated the activity of the compounds to inhibit the adhesion of monocytes to colon epithelial cells is triggered by a pro-inflammatory cytokine, tumour necrosis factor (TNF)-α. The in vitro activity of the compounds, 13b (an ureido-derivative), 14c, 14j, 14k, 14n (thioureido-), 18c and 18d (sulfonamido-), was in correlation with in vivo anti-colitis activity revealed as significant recovery in body- and colon-weights and colon myeloperoxidase level, a biochemical marker of inflammation reflecting neutrophil infiltration. In vivo, TNBS-induced changes in the expression of inflammatory cytokines (TNF-α, IL-6, IL-1ß, IL-10, and TGF-ß), NLRP3 inflammasome components (NLRP-3, Caspase-1, and IL-18), and epithelial junction molecules (E-cadherin, claudin2/3, and ZO-1) were blocked and recovered by oral administration of the compounds (1 mg/kg). Compound 14n which showed the best efficacy can be a promising lead for orally available therapeutics for pathology of IBD.


Assuntos
Anti-Inflamatórios/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Piridinas/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Células Cultivadas , Colite/induzido quimicamente , Colite/tratamento farmacológico , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Células HT29 , Humanos , Doenças Inflamatórias Intestinais/patologia , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Ácido Trinitrobenzenossulfônico , Células U937
5.
Life Sci ; 242: 117220, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881230

RESUMO

BACKGROUND/AIMS: Previous studies have demonstrated that Galactooligosaccharides (GOS), known as "bifidus factor", has anti-inflammatory effects. Colitis, a kind of colonic inflammatory damage could be induced by different chemicals. The pathogenesis and mechanism of colitis remains unclear, and may be related to intestinal microflora, genetic susceptibility or immune factors. The aim is to explore the effects of GOS on intestinal flora and its anti-inflammatory effects in Dextran Sulfate Sodium (DSS) induced murine colitis and extrapolate the underlying mechanism. MAIN METHODS: Initially, 5% DSS was used to induced colitis by free access to drinking water for 5-7 days. Then the mice were treated with GOS 1 day after DSS treatment. Colon samples were evaluated grossly using a microscope. The percentage of Treg and Th17 cells was analyzed by flow cytometry. The levels of cytokines secretion and mRNA expression were detected by ELISA and real-time PCR. The level of protein was detected by western blot. KEY FINDINGS: GOS attenuated DSS induced body weight loss and also reduced the increase in disease index caused by DSS. GOS ameliorated DSS induced colonic histological damage. The protective effect of GOS on DSS induced colitis may be partly attributed to intestinal flora regulation and Th17/Treg imbalance. Furthermore, GOS markedly decreased cytokines (IL-6, IL-18, IL-13 and IL-33) secretion and mRNA expression in colon tissues, through inhibiting activation of NF-κB pathways. SIGNIFICANCE: GOS could prevent the DSS induced colitis through intestinal flora regulation and reduce the secretion of inflammation related cytokines relying on the NF-κB signaling pathway.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , NF-kappa B/metabolismo , Oligossacarídeos/uso terapêutico , Panteteína/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Colite/induzido quimicamente , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Microbioma Gastrointestinal/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Panteteína/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos
6.
S D Med ; 72(10): 454-458, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31816206

RESUMO

Several immunotherapeutic agents function against the T cell immune checkpoint inhibitor pathways thereby reestablishing immune response to elusive malignancies. Namely, the programmed death-1 co-receptor (PD-1) or ligand (PD-L1) and cytotoxic T lymphocyte- associated protein 4 (CTLA-4) are well known checkpoint targets of current FDA approved drugs. Among these drugs nivolumab, an IgG4 anti-PD-1 antibody, and ipilimumab, an anti-CTLA-4 antibody, are used to treat numerous malignancies but carry a large list of potential side effects termed immune-related adverse effects (irAEs). We describe the presentation, clinical course, and resolution of steroid-resistant immune checkpoint inhibitor-induced colitis secondary to administration of these two drugs in a 66-year-old female patient treated with infliximab.


Assuntos
Anticorpos Monoclonais , Colite , Infliximab/uso terapêutico , Idoso , Anticorpos Monoclonais/uso terapêutico , Colite/induzido quimicamente , Colite/imunologia , Colite/terapia , Feminino , Humanos , Ipilimumab/efeitos adversos , Nivolumabe/efeitos adversos , Resultado do Tratamento
7.
Acta Cir Bras ; 34(10): e201901004, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31851212

RESUMO

PURPOSE: To evaluate the effects of infliximab on the inflammation of the colonic mucosa devoid from fecal stream. METHODS: Twenty-four rats were submitted to a Hartmann's procedure. They remained for 12 weeks with the fecal derivation to development of diversion colitis on excluded colorectal stump. After this period, they were divided into 3 groups: one group received intervention with saline (2.0 mL / week), other group infliximab at doses of 5 mg/kg/week and the other 10 mg/kg/week for five consecutively weeks. Concluded the intervention period, the animals were euthanized to remove colon segments with and without fecal stream. Colitis was diagnosed by histological analysis and the degree of inflammation by validated score. The neutrophilic infiltrate was evaluated by tissue expression of myeloperoxidase identified by immunohistochemical. The tissue content of myeloperoxidase was measured by computer-assisted image analysis. RESULTS: The inflammatory score was high in colonic segments without fecal stream. The intervention with infliximab reduced the inflammatory score in excluded colonic segments. The content of myeloperoxidase was reduced in colonic segments of animals treated with infliximab mainly in high concentrations. CONCLUSION: Intervention with infliximab reduced the inflammation and the neutrophil infiltrate in colonic segments devoid of the fecal stream.


Assuntos
Colite/tratamento farmacológico , Fármacos Gastrointestinais/farmacologia , Infliximab/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Fezes , Trânsito Gastrointestinal/efeitos dos fármacos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Peroxidase/análise , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
8.
Medicine (Baltimore) ; 98(51): e18139, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31860960

RESUMO

RATIONALE: Rituximab is recommended to induce remission of severe granulomatosis with polyangiitis (GPA). Plasma exchange (PE) may be considered in the setting of rapidly progressive glomerulonephritis (RPGN) with a serum creatinine increase of more than 5.6 mg/dl or diffuse alveolar hemorrhage (DAH). However, there are no sufficient studies on combination therapy with rituximab and PE in GPA. PATIENT CONCERNS: A 23-year-old woman was admitted with fever, abdominal pain, and diarrhea on suspicion of infectious colitis. Colonoscopy showed hemorrhagic colitis and antibiotic treatment was ineffective. Physical examination revealed episcleritis and skin lesions similar to Janeway lesions or Osler nodes on her palms and soles. Transesophageal echocardiogram (TEE) revealed mitral valve vegetation mimicking infective endocarditis. However, no pathogen was grown in the blood culture. Ten days after admission, blood-tinged sputum and respiratory distress developed. Imaging studies of lung, bronchoscopy, and bronchoalveolar lavage indicated DAH. Moreover, serum creatinine levels rapidly increased from 0.8 mg/dl to 6.1 mg/dl with proteinuria. DIAGNOSIS: The patient was diagnosed with GPA and non-infectious endocarditis, DAH, and RPGN, based on a biopsy which revealed pauci-immune crescentic glomerulonephritis with granuloma and leukocytoclastic vasculitis and antineutrophil cytoplasmic antibodies against proteinase 3- positivity. INTERVENTIONS: Initial methylprednisolone pulse therapy (1 g daily for 3 days) proved unsuccessful. After initiating PE, creatinine levels began to slowly decline, but DAH continued to deteriorate. Rituximab combined with PE therapy was considered. We performed PE every 2 to 3 days for 5 total treatments combined with rituximab (375 mg/m, once weekly for 4 weeks). OUTCOMES: After the combination treatment of rituximab and PE, alveolar hemorrhage stopped. Chest X-ray and laboratory data, including serum creatinine and hemoglobin, notably improved. Mitral valve vegetation was no longer observed in follow-up TEE. GPA remained stable with low dose prednisolone and immunosuppressants over a follow-up period of 5 years. LESSONS: This case suggests that the use of rituximab and concurrent PE may represent a promising combination for severe and refractory GPA.


Assuntos
Granulomatose com Poliangiite/patologia , Granulomatose com Poliangiite/terapia , Troca Plasmática/métodos , Rituximab/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Biópsia por Agulha , Colite/diagnóstico , Colite/etiologia , Colonoscopia/métodos , Terapia Combinada , Esquema de Medicação , Serviço Hospitalar de Emergência , Feminino , Seguimentos , Granulomatose com Poliangiite/diagnóstico , Humanos , Imuno-Histoquímica , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
9.
Int J Nanomedicine ; 14: 8361-8378, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749615

RESUMO

Purpose: This study aimed to evaluate the anti-colitis potential of platinum nanoparticles (PtNPs). Materials and methods: 5-, 30- and 70-nm PtNPs were administered to C57BL/6 mice once daily by intragastric gavage for 8 d during and after 5-d dextran sodium sulfate treatment. Results: According to body weight change, stool blood and consistency, and colon length and histopathology, PtNPs size-dependently alleviated DSS-induced murine colitis. PtNPs enhanced gut-barrier function by upregulating the colonic expressions of heat-shock protein 25 and tight junction proteins. Based on colonic myeloperoxidase activity, colonic and peripheral levels of interleukin-6 and tumor necrosis factor-α, and peripheral counts of white blood cells, PtNPs attenuated colonic and systemic inflammation. By suppressing lipopolysaccharide-triggered production of proinflammatory mediators, including nitric oxide, tumor necrosis factor-α and interleukin-6, PtNPs exerted direct anti-inflammatory activities in RAW264.7 macrophages through a mechanism involving intracellular reactive oxygen species scavenging and Toll-like receptor 4/NF-κB signaling suppression. High-throughput 16S rRNA sequencing of fecal samples unveiled that PtNPs induced gut dysbiosis by unfavorably altering α-diversity, Firmicutes/Bacteroidetes ratio, and richness of certain specific bacteria. Conclusion: PtNPs are a promising anti-colitis agent, but may negatively impact gut-microbiota.


Assuntos
Colite/induzido quimicamente , Colite/terapia , Nanopartículas Metálicas/uso terapêutico , Platina/uso terapêutico , Doença Aguda , Administração Oral , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite/microbiologia , Colo/microbiologia , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/patologia , Lipopolissacarídeos , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
10.
Life Sci ; 239: 117021, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678552

RESUMO

OBJECTIVES: Clematichinenoside AR (AR) is a saponin extracted for traditional Chinese medicine with the effects of improving the expression of tight junction (TJ) proteins and mediating anti-inflammatory activities. However, its effect on Crohn's disease (CD) is still unknown. We aimed to investigate the impact of AR on CD-like colitis and determine the mechanism underlying its effects. METHODS: Interleukin-10 gene knockout (Il-10-/-) mice (male, fifteen weeks old) with spontaneous colitis were allocated to the positive control and AR-treated (32 mg/kg AR administered every other day by gavage for 4 weeks) groups. Wild-type (WT) mice (male, fifteen weeks old) composed the negative control group. The effects of AR on intestinal barrier function and structure and T cell responses as well as the potential mechanisms underlying these effects were investigated. RESULTS: AR treatment significantly improved spontaneous colitis in Il-10-/- mice as demonstrated by reductions in the inflammatory score, disease activity index (DAI) and levels of inflammatory factors. The effects of AR on colitis in Il-10-/- mice were related to protecting intestinal barrier function and maintaining immune system homeostasis (regulatory T cell (Treg)/T helper 17 (Th17) cell balance). The anticolitis effect of AR may partly act by downregulating PI3K/Akt signaling. CONCLUSIONS: AR may have therapeutic potential for treating CD in humans.


Assuntos
Colite/tratamento farmacológico , Colite/genética , Interleucina-10/genética , Intestinos/patologia , Saponinas/uso terapêutico , Triterpenos/uso terapêutico , Animais , Translocação Bacteriana/efeitos dos fármacos , Colite/patologia , Citocinas/metabolismo , Intestinos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos
11.
J Agric Food Chem ; 67(48): 13299-13306, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31674784

RESUMO

l-Arabinose is a monosaccharide extracted from plants or fibers, which is known to have a variety of functional properties. In this study, we aim to investigate whether l-arabinose could inhibit colitis by modulating gut microbiota. l-Arabinose was administered in mice daily in a dextran sodium sulfate (DSS)-induced colitis model. The histological analysis, disease index, and the expression of inflammatory genes were measured. 16S-rRNA sequence analysis was performed to investigate gut microbiota. Intriguingly, we found that l-arabinose could repress DSS-induced colitis and inhibit p38-/p65-dependent inflammation activation. Besides that, our data revealed that l-arabinose-modulated DSS-induced gut microbiota were disturbed. Additionally, the perturbed gut microbiota was responsible for the suppressive effects of l-arabinose on DSS-induced colitis treated with antibiotics. Lastly, Caco-2 cells were used to confirm the protective effects of l-arabinose in colitis or inflammatory bowel disease. As expected, the protein expression levels in Caco-2 cells of pro-inflammatory genes, which were treated with l-arabinose and incubated with or without tumor necrosis factor alpha. Our work suggested that l-arabinose exerts anti-inflammation effects in DSS-induced colitis. These beneficial effects have correlations with the composition, diversity, and abundance of the gut microbiota regulated by l-arabinose. l-Arabinose could be a remarkable candidate as a functional food or novel therapeutic strategy for intestinal health.


Assuntos
Arabinose/administração & dosagem , Colite/tratamento farmacológico , Colite/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Colite/induzido quimicamente , Colite/imunologia , Citocinas/genética , Citocinas/imunologia , Sulfato de Dextrana/efeitos adversos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
12.
J Agric Food Chem ; 67(48): 13282-13298, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31690068

RESUMO

Dietary supplementation with conjugated linoleic acid (CLA) has been reported to alleviate the effect of colitis in mice, but the mechanisms involved need further exploration. The study aimed to investigate how orally administered CLA alleviates dextran sulfate sodium (DSS)-induced colitis in mice. CLA was administered in five different doses: 40, 20, 10, 5, and 2.5 mg/day. Doses of CLA at 10 mg/day and higher alleviated colitis symptoms and reduced inflammation induced by DSS, in which 40, 20, and 10 mg/day CLA significantly increased the concentration of mucin2 and goblet cells, but neither 5 mg/day CLA nor 2.5 mg/day CLA had any effects. Meanwhile, 40 and 20 mg/day CLA treatments significantly upregulated the concentration of tight junction proteins (ZO-1, occludin, and claudin-3) and ameliorated epithelial apoptosis caused by DSS. Moreover, oxidative-stress-related enzymes (superoxide dismutase, glutathione peroxidase, and catalase) and inflammatory cytokines [tumor necrosis factor-α, interleukin (IL)-10, and IL-6] were modulated by 40 and 20 mg/day CLA. Furthermore, 40 mg/day CLA rebalanced the gut microbiota damaged by DSS, including reducing Bacteroides and increasing Bifidobacterium and Odoribacter. In conclusion, CLA supplementation alleviated DSS-induced colitis in a dose-dependent manner by modulating inflammatory cytokines and oxidation stress, maintaining the mucosal barrier, and reverting microbiota changes.


Assuntos
Colite/tratamento farmacológico , Citocinas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Ácidos Linoleicos Conjugados/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , Citocinas/genética , Sulfato de Dextrana/efeitos adversos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
Adv Exp Med Biol ; 1197: 97-105, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31732937

RESUMO

The colonization of body surfaces, notably of the intestine, by a complex microbiota is generally highly mutualistic, where vital functions are provided by the commensal microbiota to the host, including the synthesis of vitamins, the degradation of complex polysaccharides into small chain fatty acids (which are essential for the maintenance of the intestinal epithelial barrier), and, finally, the outcompetition of pathogens that accidentally gain access to the body ("colonization resistance") (Chow et al. 2011; Backhed 2005). However, under certain conditions, such as changes of environmental factors in a genetically predisposed host, some of these normally symbiotic bacteria may act as pathogens and induce pathologies. Hence, the term "pathobionts" was coined for these bacterial species with ambiguous biological properties (Round et al. 2009).


Assuntos
Colite , Helicobacter , Animais , Colite/microbiologia , Modelos Animais de Doenças , Helicobacter/fisiologia , Humanos , Intestinos/microbiologia
15.
Life Sci ; 238: 116968, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31628914

RESUMO

AIMS: Colorectal cancer (CRC) is the third most common cancer worldwide. Nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of many cytoprotective genes, plays a protective role in carcinogenesis. Recent studies have identified a specific gene-expression signature regulated by the Nrf2 pathway in lung adenocarcinoma and head-and-neck squamous cell cancer. However, the roles of Nrf2 in the development of colitis-associated colorectal cancer (CACC) have not been well characterized. Nrf2 target genes as prognostic biomarkers in CACC remain to be explored. Thus, this work aimed to identify the molecular changes that occur during mouse CACC progression to facilitate the development of diagnostic and prognostic biomarkers. MAIN METHODS: The CACC model was established using azoxymethane (AOM) with dextran sulfate sodium salt (DSS) in BALB/c mice for 3 weeks to induce colitis-associated adenoma (CAA, early stage) and for 9 weeks to induce colitis-associated carcinoma (CAC, late stage). Using RNA-sequencing and bioinformatics analyses we examined the mRNA expression profiles of 6 groups: wild-type control (WT-C), WT-CAA, WT-CAC, Nrf2 knockout control (Nrf2KO-C), Nrf2KO-CAA, and Nrf2KO-CAC. KEY FINDINGS: In the AOM/DSS model of colitis-associated tumorigenesis, Nrf2-/- mice showed a phenotype similar to WT mice, but with significantly more tumors and a much higher percentage of adenocarcinomas. We identified 47 novel Nrf2 genes via gene expression profiling of tumor samples. Survival analysis showed that 23 of these genes were biomarkers of a poor prognosis in colon cancer patients. SIGNIFICANCE: Nrf2 target genes deserve exploration as prognostic and therapeutic targets for CRC.


Assuntos
Biomarcadores/metabolismo , Carcinogênese/patologia , Colite/complicações , Neoplasias Colorretais/diagnóstico , Regulação Neoplásica da Expressão Gênica , Fator 2 Relacionado a NF-E2/fisiologia , Animais , Azoximetano/toxicidade , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinógenos/toxicidade , Colite/induzido quimicamente , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
16.
Nat Commun ; 10(1): 4614, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601814

RESUMO

Autophagy is a central component of integrated stress responses that influences many inflammatory diseases, including inflammatory bowel disease (IBD) and colorectal cancer (CRC). While the core machinery is known, the molecular basis of the epigenetic regulation of autophagy and its role in colon inflammation remain largely undefined. Here, we report that BRG1, an ATPase subunit of the SWI/SNF chromatin remodeling complex, is required for the homeostatic maintenance of intestinal epithelial cells (IECs) to prevent the inflammation and tumorigenesis. BRG1 emerges as a key regulator that directly governs the transcription of Atg16l1, Ambra1, Atg7 and Wipi2, which are important for autophagosome biogenesis. Defective autophagy in BRG1-deficient IECs results in excess reactive oxygen species (ROS), which leads to the defects in barrier integrity. Together, our results establish that BRG1 may represent an autophagy checkpoint that is pathogenetically linked to colitis and is therefore likely a potential therapeutic target for disease intervention.


Assuntos
Autofagia/fisiologia , Colite/etiologia , Neoplasias Colorretais/etiologia , DNA Helicases/genética , Doenças Inflamatórias Intestinais/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Animais , Estudos de Casos e Controles , Colite/complicações , Colite/patologia , Neoplasias Colorretais/genética , DNA Helicases/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica , Humanos , Doenças Inflamatórias Intestinais/patologia , Camundongos Knockout , Proteínas Nucleares/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo
17.
Cell Physiol Biochem ; 53(5): 774-793, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31647207

RESUMO

BACKGROUND/AIMS: Deregulation of the complex interaction among host genetics, gut microbiota and environmental factors on one hand and aberrant immune responses on the other hand, are known to be associated with the development of inflammatory bowel disease. Recent studies provided strong evidence that autophagy plays a key role in the etiology of Crohn's disease (CD). Probiotics may exhibit many therapeutic properties, including anti-inflammatory abilities. While successful results have been obtained in ulcerative colitis patients, probiotics remain inefficient in CD for unknown reason. It remains therefore important to better understand their molecular mechanisms of action. METHODS: The activation of autophagy was examined by stimulating bone marrow-derived dendritic cells by the bacteria, followed by confocal microscopy and western blot analysis. The impact of blocking in vitro autophagy was performed in peripheral blood mononuclear cells using 3-methyl adenine or bafilomycin followed by cytokine secretion measurement by ELISA. The role of autophagy in the anti-inflammatory capacities of the bacterial strains was evaluated in vivo using an acute trinitrobenzene sulfonic acid-induced murine model of colitis. The impact of BMDC was evaluated by adoptive transfer, notably using bone marrow cells derived from autophagy-related 16-like 1-deficient mice. RESULTS: We showed that selected lactobacilli and bifidobacteria are able to induce autophagy activation in BMDCs. Blocking in vitro autophagy abolished the capacity of the strains to induce the release of the anti-inflammatory cytokine interleukin-10, while it exacerbated the secretion of the pro-inflammatory cytokine interleukin-1ß. We confirmed in the TNBS-induced mouse model of colitis that autophagy is involved in the protective capacity of these selected strains, and showed that dendritic cells are involved in this process. CONCLUSION: We propose autophagy as a novel mechanism involved in the regulatory capacities of probiotics.


Assuntos
Autofagia , Bifidobacterium/fisiologia , Lactobacillus/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Proteínas Relacionadas à Autofagia , Células da Medula Óssea/citologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Colite/induzido quimicamente , Colite/microbiologia , Colite/patologia , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Feminino , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout
18.
J Biochem Mol Toxicol ; 33(11): e22400, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31593355

RESUMO

Inflammatory bowel disease (IBD) is a continual ailment condition which engrosses the entire alimentary canal. The IBD can be primarily distinguished into two forms, ulcerative colitis, and Crohn's disease. The major symptoms of IBD include pustules or abscesses, severe abdominal pain, diarrhea, fistula, and stenosis, which may directly affect the patient's quality of life. A variety of mediators can stimulate the circumstances of IBD, some examples include infections by microbes such as bacteria, perturbation of the immune system and the surrounding environment of the intestines. Severe colitis was stimulated in the experimental animals through administering 4% dextran sulfate sodium (DSS) which is mixed in water ad libitum for 6 days. Eriocitrin (30 mg/kg) was then administered to the experimental animals followed by the induction of severe colitis to evaluate the therapeutic prospective of eriocitrin against the colon inflammation stimulated by DSS. In this study, eriocitrin (30 mg/kg) demonstrated significant (P < .05) attenuation activity against the DSS-stimulated severe colitis in experimental animals. Eriocitrin counteracted all of the clinical deleterious effects induced by DSS, such as body-weight loss, colon shortening, histopathological injury, accretion of infiltrated inflammatory cells at the inflamed region and the secretion of inflammatory cytokines. The results clearly showed that eriocitrin effectively attenuated DSS-induced acute colitis in experimental animals.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/farmacologia , Flavanonas/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/administração & dosagem , Citrus/química , Colo/efeitos dos fármacos , Colo/patologia , Ciclo-Oxigenase 2/análise , Citocinas/metabolismo , Modelos Animais de Doenças , Flavanonas/administração & dosagem , Inflamação/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/análise , Peroxidase/metabolismo , Extratos Vegetais/administração & dosagem , Índice de Gravidade de Doença , Perda de Peso/efeitos dos fármacos
19.
Appl Microbiol Biotechnol ; 103(21-22): 8937-8945, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520133

RESUMO

Inflammatory bowel diseases are chronic and relapsing-remitting disorders that affect the gastrointestinal tract. Previously, the administration of folate and riboflavin-producing lactic acid bacteria (LAB) or an immune-modulating strain showed beneficial effects as they were able to reduce the acute inflammation in mouse models. The aim of this work was to evaluate a mixture of vitamin-producing and immune-modulating LAB administering together with an anti-inflammatory drug during the remission period of a mouse model of recurrent colitis. BALB/c mice were intrarectally instilled with trinitrobenzene sulfonic acid (TNBS) and those who recovered from this acute challenge were given the LAB mixture, mesalazine, or the combination of both (mesalazine + LAB) during 21 days, followed by a second challenge with TNBS. Control mice instilled with ethanol (vehicle of TNBS) and receiving the different treatments were also evaluated in order to study the effect of chronic anti-inflammatory therapy. The combination of mesalazine and LAB mixture was the most effective to decrease the intestinal damage at macroscopic and histological levels and to reduce pro-inflammatory cytokines (IL-6 and TNF-α) in intestinal fluids. In animals instilled with ethanol, mesalazine produced a loss of body weight and intestinal damages with increased IL-6. These side effects were prevented by the co-administration of mesalazine and the LAB mixture. The LAB blend did not affect the primary anti-inflammatory treatment, was able to improve it, and also prevented the side effects of this therapy.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Colite/tratamento farmacológico , Lactobacillales/metabolismo , Probióticos/administração & dosagem , Vitaminas/metabolismo , Animais , Colite/genética , Colite/imunologia , Modelos Animais de Doenças , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
20.
Nat Commun ; 10(1): 4368, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554819

RESUMO

The colonic epithelial turnover is driven by crypt-base stem cells that express the R-spondin receptor Lgr5. Signals that regulate epithelial regeneration upon stem cell injury are largely unknown. Here, we explore the dynamics of Wnt signaling in the colon. We identify two populations of cells with active Wnt signaling: highly proliferative Lgr5+/Axin2+ cells, as well as secretory Lgr5-/Axin2+ cells. Upon Lgr5+ cell depletion, these cells are recruited to contribute to crypt regeneration. Chemical injury induced by DSS leads to a loss of both Lgr5+ cells and Axin2+ cells and epithelial regeneration is driven by Axin2- cells, including differentiated Krt20+ surface enterocytes. Regeneration requires stromal Rspo3, which is present at increased levels upon injury and reprograms Lgr5- but Lgr4+ differentiated cells. In contrast, depletion of stromal Rspo3 impairs crypt regeneration, even upon mild injury. We demonstrate that Rspo3 is essential for epithelial repair via induction of Wnt signaling in differentiated cells.


Assuntos
Colo/fisiologia , Mucosa Intestinal/fisiologia , Regeneração/fisiologia , Células-Tronco/metabolismo , Trombospondinas/metabolismo , Animais , Proteína Axina/genética , Proteína Axina/metabolismo , Diferenciação Celular/genética , Colite/genética , Colite/metabolismo , Colo/metabolismo , Enterócitos/metabolismo , Perfilação da Expressão Gênica/métodos , Mucosa Intestinal/metabolismo , Queratina-20/genética , Queratina-20/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Regeneração/genética , Células-Tronco/citologia , Trombospondinas/genética , Via de Sinalização Wnt/genética
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