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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
J Microbiol Biotechnol ; 29(9): 1369-1374, 2019 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-31564078

RESUMO

We isolated Lactobacillus mucosae NK41 and Bifidobacterium longum NK46 from human feces, which induced BDNF expression in corticosterone-stimulated SH-SY5Y cells, and examined their anti-depressive effects in mice. NK41, NK46, and their (1:1) mixture significantly mitigated immobilization stress (IS)-induced anxiety-like/depressive behaviors, hippocampal NF-κB activation, BDNF expression, Iba1+ cell population, and blood corticosterone, TNF-α, IL- 6, and lipopolysaccharide levels. Furthermore, they inhibited colitis marker NF-κB activation, and TNF-α expression in mice with IS-induced anxiety/depression. They additionally suppressed gut Proteobacteria and Bacteroidetes populations and bacterial lipopolysaccharide production. These findings suggest that NK41 and NK46 may alleviate anxiety/depression and colitis by suppressing gut dysbiosis.


Assuntos
Ansiedade/dietoterapia , Bifidobacterium longum , Depressão/dietoterapia , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus , Probióticos/farmacologia , Probióticos/uso terapêutico , Animais , Antidepressivos/administração & dosagem , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Ansiedade/sangue , Ansiedade/microbiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Colite/microbiologia , Colite/patologia , Corticosterona/sangue , Depressão/sangue , Depressão/microbiologia , Modelos Animais de Doenças , Disbiose/microbiologia , Disbiose/patologia , Fezes/microbiologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Interleucina-6/sangue , Lipopolissacarídeos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , NF-kappa B/metabolismo , Probióticos/administração & dosagem , Estresse Psicológico/sangue , Estresse Psicológico/microbiologia , Estresse Psicológico/psicologia , Fator de Necrose Tumoral alfa/sangue
8.
DNA Cell Biol ; 38(10): 1025-1029, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31532239

RESUMO

Neutrophil trafficking into damaged or infected tissues is essential for the initiation of inflammation, clearance of pathogens and damaged cells, and ultimately tissue repair. Neutrophil recruitment is highly dependent on the stepwise induction of adhesion molecules and promigratory chemokines and cytokines. A number of studies in animal models have shown the efficacy of cannabinoid receptor 2 (CB2) agonists in limiting inflammation in a range of preclinical models of inflammation, including colitis, atherosclerosis, multiple sclerosis, and ischemia-reperfusion injury. Recent work in preclinical models of inflammation raises two questions: by what mechanisms do CB2 agonists provide anti-inflammatory effects during acute inflammation and what challenges exist in the translation of CB2 modulating therapeutics into the clinic.


Assuntos
Aterosclerose/genética , Colite/genética , Esclerose Múltipla/genética , Neutrófilos/metabolismo , Receptor CB2 de Canabinoide/genética , Traumatismo por Reperfusão/genética , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Aterosclerose/patologia , Agonistas de Receptores de Canabinoides/uso terapêutico , Antagonistas de Receptores de Canabinoides/uso terapêutico , Colite/tratamento farmacológico , Colite/metabolismo , Colite/patologia , Citocinas/metabolismo , Citocinas/farmacologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Inflamação , Ligantes , Camundongos , Camundongos Knockout , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Infiltração de Neutrófilos , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/deficiência , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
9.
Infect Immun ; 87(11)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31481410

RESUMO

Fibrosis is a significant complication of intestinal disorders associated with microbial dysbiosis and pathobiont expansion, notably Crohn's disease (CD). Mechanisms that favor fibrosis are not well understood, and therapeutic strategies are limited. Here we demonstrate that colitis-susceptible Il10-deficient mice develop inflammation-associated fibrosis when monoassociated with adherent/invasive Escherichia coli (AIEC) that harbors the yersiniabactin (Ybt) pathogenicity island. Inactivation of Ybt siderophore production in AIEC nearly abrogated fibrosis development in inflamed mice. In contrast, inactivation of Ybt import through its cognate receptor FyuA enhanced fibrosis severity. This corresponded with increased colonic expression of profibrogenic genes prior to the development of histological disease, therefore suggesting causality. fyuA-deficient AIEC also exhibited greater localization within subepithelial tissues and fibrotic lesions that was dependent on Ybt biosynthesis and corresponded with increased fibroblast activation in vitro Together, these findings suggest that Ybt establishes a profibrotic environment in the host in the absence of binding to its cognate receptor and indicate a direct link between intestinal AIEC and the induction of inflammation-associated fibrosis.


Assuntos
Colite/microbiologia , Escherichia coli/metabolismo , Fibrose/etiologia , Inflamação/microbiologia , Interleucina-10/metabolismo , Fenóis/metabolismo , Tiazóis/metabolismo , Animais , Aderência Bacteriana , Colite/complicações , Colite/patologia , Regulação Bacteriana da Expressão Gênica , Vida Livre de Germes , Humanos , Inflamação/patologia , Interleucina-10/genética , Camundongos , Camundongos Knockout , Mutação
10.
Life Sci ; 236: 116833, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491456

RESUMO

AIMS: Inflammatory bowel disease is a chronic relapsing inflammation that affects the gastrointestinal tract, causing changes in colonic motility. The evolution of these changes is not completely understood and possibly related to symptoms that appear in different degrees of the intestinal inflammation. Therefore, our aim is evaluate during 14 days of assessment aspects of colonic contractility using 2,4,6-trinitrobenzenesulfonic acid (TNBS) model of inflammation in rats and associate the inflammatory process with colonic motility. METHODS: Contractility and inflammatory parameters were assessed in the same animal in six different moments: before intestinal inflammation induction, 2, 5, 8, 11, and 14 days after induction. The mechanical activity was determined by alternating current biosusceptometry (ACB) and subdivided into rhythmic propagating ripples (RPR) and rhythmic propulsive motor complexes (RPMC). We assessed inflammation by determining myeloperoxidase activity in feces. RESULTS: Transient and permanent changes were observed in colonic motility as a function of the inflammatory process evaluated through myeloperoxidase activity. We identified two contraction profiles: RPR and RPMC. The microscopic analysis demonstrated a depth of damage caused by an injury that was associated with changes in motility. CONCLUSIONS: We implemented a robust and adequate (specific) signal processing to quantify two measured colonic frequency patterns. Thus, we performed a detailed temporal analysis of the consequences of TNBS-induced inflammation on colonic motility in rats. Our approach enables further long-term assessments in the same animal with different mechanisms and duration of injury, remission, treatments and their motor consequences.


Assuntos
Colite/patologia , Modelos Animais de Doenças , Inflamação/patologia , Doenças Inflamatórias Intestinais/fisiopatologia , Mucosa Intestinal/fisiopatologia , Contração Muscular , Ácido Trinitrobenzenossulfônico/toxicidade , Animais , Colite/induzido quimicamente , Inflamação/induzido quimicamente , Masculino , Ratos , Ratos Wistar
11.
Gastroenterology ; 157(5): 1323-1337, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31401143

RESUMO

BACKGROUND & AIMS: Epithelial tight junctions are compromised in gastrointestinal disease. Processes that contribute to the resulting barrier loss include endocytic occludin removal from the tight junction and reduced occludin expression. Nevertheless, the relatively-normal basal phenotype of occludin knockout (KO) mice has been taken as evidence that occludin does not contribute to gastrointestinal barrier function. We asked whether stress could unmask occludin functions within intestinal epithelia. METHODS: Wildtype (WT), universal and intestinal epithelial-specific occludin KO, and villin-EGFP-occludin transgenic mice as well as WT and occludin knockdown (KD) Caco-2BBe cell monolayers were challenged with DSS, TNBS, staurosporine, 5-FU, or TNF. Occludin and caspase-3 expression were assessed in patient biopsies. RESULTS: Intestinal epithelial occludin loss limited severity of DSS- and TNBS-induced colitis due to epithelial resistance to apoptosis; activation of both intrinsic and extrinsic apoptotic pathways was blocked in occludin KO epithelia. Promoter analysis revealed that occludin enhances CASP3 transcription and, conversely, that occludin downregulation reduces caspase-3 expression. Analysis of biopsies from Crohn's disease and ulcerative colitis patients and normal controls demonstrated that disease-associated occludin downregulation was accompanied by and correlated with reduced caspase-3 expression. In vitro, cytokine-induced occludin downregulation resulted in reduced caspase-3 expression and resistance to intrinsic and extrinsic pathway apoptosis, demonstrating an overall protective effect of inflammation-induced occludin loss. CONCLUSIONS: The tight junction protein occludin regulates apoptosis by enhancing caspase-3 transcription. These data suggest that reduced epithelial caspase-3 expression downstream of occludin downregulation is a previously-unappreciated anti-apoptotic process that contributes to mucosal homeostasis in inflammatory conditions.


Assuntos
Apoptose , Caspase 3/metabolismo , Colite/enzimologia , Colo/enzimologia , Células Epiteliais/enzimologia , Mucosa Intestinal/enzimologia , Ocludina/metabolismo , Animais , Células CACO-2 , Estudos de Casos e Controles , Caspase 3/deficiência , Caspase 3/genética , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Colite Ulcerativa/enzimologia , Colite Ulcerativa/patologia , Colo/patologia , Doença de Crohn/enzimologia , Doença de Crohn/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Células Epiteliais/patologia , Humanos , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ocludina/deficiência , Ocludina/genética , Transdução de Sinais , Ácido Trinitrobenzenossulfônico , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
12.
DNA Cell Biol ; 38(11): 1338-1345, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31464523

RESUMO

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease, which often affects colon or rectum or both. It is now well recognized that sphingosine kinases-1/sphingosine-1-phosphate (S1P) signaling may have a very significant potential as targets for therapeutic intervention in UC. Compared with the pure dextran sodium sulfate group, administration of PF543 significantly reduced clinical symptoms with less weight loss, diarrhea, and shortening of the colon. The severity of colitis was improved with reduced disease activity index and degree of histological damage in colon. Moreover, treatment with PF543 not only decreased S1P but also inhibited mRNA expression of proinflammatory factors such as interleukin (IL)-1ß and IL-6. This suggests that PF543 might exhibit an anti-inflammatory function against colitis through inhibition of expression of proinflammatory factors.


Assuntos
Colite/patologia , Colo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Metanol/análogos & derivados , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Pirrolidinas/farmacologia , Animais , Colite/sangue , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Lisofosfolipídeos/sangue , Masculino , Metanol/farmacologia , Metanol/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Pirrolidinas/uso terapêutico , Esfingosina/análogos & derivados , Esfingosina/sangue , Baço/efeitos dos fármacos , Baço/patologia , Especificidade por Substrato
13.
Nutrients ; 11(8)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362373

RESUMO

BACKGROUND: In this study, we investigate the impact of epigallocatechin gallate (EGCG), the most abundant and potent catechin in green tea, on a mouse model of inflammatory bowel disease (IBD) and the underlying mechanisms of action. METHODS: C57BL/6J mice were subjected to dextran sulfate sodium (DSS)-induced IBD-like disease and then randomly divided into three groups: Model group (MD), low-dose EGCG group (LE, 20 mg/kg/d), and high-dose EGCG group (HE, 50 mg/kg/d). DSS-induced clinical and macroscopic changes were monitored daily. Intestinal permeability was assessed by FITC-Dextran assay. RESULTS: Both high- and low-dose EGCG treatment alleviated clinical manifestations including body weight loss and disease activity index (DAI) of DSS-induced colitis. The DAI score was significantly improved after two days of EGCG treatment. At the end of the study, the macroscopic severity score (MSS) of HE and LE treatment groups were 2.4 ± 1.2, and 2.2 ± 1.0, respectively, significantly lower than that of the controls (5.0 ± 2.1). EGCG treatment also prevented colon shortening, and improved intestinal permeability and histopathological changes. In addition, EGCG treatment attenuated colon inflammation by suppressing colonic levels of pro-inflammatory cytokines IL-6, MCP-1, and TNF-alpha, and inhibited CD3+ T cell and CD68+ macrophage infiltration. CONCLUSION: EGCG is effective in inflammatory colitis because it reduces cellular and molecular inflammation, and reduces intestinal permeability.


Assuntos
Anti-Inflamatórios/administração & dosagem , Catequina/análogos & derivados , Colite/prevenção & controle , Colo/efeitos dos fármacos , Citocinas/metabolismo , Fármacos Gastrointestinais/administração & dosagem , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Catequina/administração & dosagem , Colite/imunologia , Colite/metabolismo , Colite/patologia , Colo/imunologia , Colo/metabolismo , Colo/patologia , Citocinas/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Mediadores da Inflamação/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Permeabilidade , Linfócitos T/imunologia , Linfócitos T/metabolismo
14.
Nutrients ; 11(8)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362418

RESUMO

Inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohn's disease, are chronic disorders of the gastrointestinal tract, although the exact causes of IBD remain unknown. Present treatments for IBDs have poor tolerability and insufficient therapeutic efficacy, thus, alternative therapeutic approaches are required. Soybean-derived isoflavones have multiple bioactivities such as anti-inflammation. However, the low water solubility of soybean isoflavones limits their bioavailability and practical use. Therefore, in order to study the preventive effects of water-soluble soybean isoflavones on colonic inflammatory status, we examined soybean-derived isoflavone glycosides (SIFs) in a dextran sodium sulfate (DSS)-induced murine colitis model and in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. Oral administration of SIF (0.5 w/v%) attenuated DSS-induced colitis in terms of body weight decrease, colon shortening, epithelial apoptosis, histological score, mRNA levels of inflammatory cytokines, and immune cell infiltration in colon tissues. In the in vitro assessment, we observed the inhibitory effects of SIF on the production of nitric oxide and prostaglandin E2, via suppression of inducible nitric oxide synthase and cyclooxygenase-2 expression in RAW264.7 macrophages in response to LPS. Furthermore, we confirmed that the expression of inflammatory cytokines and chemokines were decreased by pre-treatment with SIF in LPS-activated RAW264.7 macrophages. Moreover, we demonstrated that SIF suppressed inflammatory mediators involved in nuclear factor-κB signaling pathway via inhibitory κB kinase phosphorylation and degradation of inhibitory κB. Our results suggested that SIF may be beneficial for the remission of colonic inflammatory status including IBDs.


Assuntos
Anti-Inflamatórios/administração & dosagem , Colite/prevenção & controle , Colo/efeitos dos fármacos , Sulfato de Dextrana , Isoflavonas/administração & dosagem , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Soja , Animais , Anti-Inflamatórios/isolamento & purificação , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Colo/imunologia , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Isoflavonas/isolamento & purificação , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Células RAW 264.7 , Indução de Remissão , Transdução de Sinais , Soja/química
15.
Blood ; 134(9): 765-775, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31262781

RESUMO

Platelets are specialized cells essential for hemostasis that also function as crucial effectors capable of mediating inflammatory and immune responses. These sentinels continually survey their environment and discriminate between homeostatic and danger signals such as modified components of the extracellular matrix. The glycosaminoglycan hyaluronan (HA) is a major extracellular matrix component that coats the vascular lumen and, under normal conditions, restricts access of inflammatory cells. In response to tissue damage, the endothelial HA matrix enhances leukocyte recruitment and regulates the early stages of the inflammatory response. We have shown that platelets can degrade HA from the surface of activated endothelial cells via the enzyme hyaluronidase-2 (HYAL2) and that HYAL2 is deficient in platelets isolated from patients with inflammatory bowel disease (IBD). Platelets are known to be involved in the pathogenesis of several chronic disease states, including IBD, but they have been largely overlooked in the context of intestinal inflammation. We therefore wanted to define the mechanism by which platelet HYAL2 regulates the inflammatory response during colitis. In this study, we provide evidence that HA catabolism is disrupted in human intestinal microvascular endothelial cells isolated from patients with IBD. Furthermore, mice deficient in HYAL2 are more susceptible to an acute model of colitis, and this increased susceptibility is abrogated by transfusion of HYAL2-competent platelets. Finally, we show that platelets, via HYAL2-dependent degradation of endothelial HA, regulate the early stages of inflammation in colitis by limiting leukocyte extravasation.


Assuntos
Plaquetas/imunologia , Colite/imunologia , Hialuronoglucosaminidase/imunologia , Animais , Plaquetas/patologia , Células Cultivadas , Colite/patologia , Células Endoteliais/imunologia , Células Endoteliais/patologia , Proteínas Ligadas por GPI/imunologia , Humanos , Ácido Hialurônico/imunologia , Inflamação/imunologia , Inflamação/patologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Knockout
16.
Gastroenterology ; 157(5): 1293-1309, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31302143

RESUMO

BACKGROUND & AIMS: It is not clear how regulation of T-cell function is altered during development of inflammatory bowel diseases (IBD). We studied the mechanisms by which geranylgeranyltransferase-mediated prenylation controls T-cell localization to the intestine and chronic inflammation. METHODS: We generated mice with T-cell-specific disruption of the geranylgeranyltransferase type I, beta subunit gene (Pggt1b), called Pggt1bΔCD4 mice, or the ras homolog family member A gene (Rhoa), called RhoaΔCD4 mice. We also studied mice with knockout of CDC42 or RAC1 and wild-type mice (controls). Intestinal tissues were analyzed by histology, multiphoton and confocal microscopy, and real-time polymerase chain reaction. Activation of CDC42, RAC1, and RHOA were measured with G-LISA, cell fractionation, and immunoblots. T cells and lamina propria mononuclear cells from mice were analyzed by flow cytometry or transferred to Rag1-/- mice. Mice were given injections of antibodies against integrin alpha4beta7 or gavaged with the RORC antagonist GSK805. We obtained peripheral blood and intestinal tissue samples from patients with and without IBD and analyzed them by flow cytometry. RESULTS: Pggt1bΔCD4 mice developed spontaneous colitis, characterized by thickening of the intestinal wall, edema, fibrosis, accumulation of T cells in the colon, and increased expression of inflammatory cytokines. Compared with control CD4+ T cells, PGGT1B-deficient CD4+ T cells expressed significantly higher levels of integrin alpha4beta7, which regulates their localization to the intestine. Inflammation induced by transfer of PGGT1B-deficient CD4+ T cells to Rag1-/- mice was blocked by injection of an antibody against integrin alpha4beta7. Lamina propria of Pggt1bΔCD4 mice had increased numbers of CD4+ T cells that expressed RORC and higher levels of cytokines produced by T-helper 17 cells (granulocyte-macrophage colony-stimulating factor, interleukin [IL]17A, IL17F, IL22, and tumor necrosis factor [TNF]). The RORC inverse agonist GSK805, but not antibodies against IL17A or IL17F, prevented colitis in Pggt1bΔCD4 mice. PGGT1B-deficient CD4+ T cells had decreased activation of RHOA. RhoAΔCD4 mice had a similar phenotype to Pggt1bΔCD4 mice, including development of colitis, increased numbers of CD4+ T cells in colon, increased expression of integrin alpha4beta7 by CD4+ T cells, and increased levels of IL17A and other inflammatory cytokines in lamina propria. T cells isolated from intestinal tissues from patients with IBD had significantly lower levels of PGGT1B than tissues from individuals without IBD. CONCLUSION: Loss of PGGT1B from T cells in mice impairs RHOA function, increasing CD4+ T-cell expression of integrin alpha4beta7 and localization to colon, resulting in increased expression of inflammatory cytokines and colitis. T cells isolated from gut tissues from patients with IBD have lower levels of PGGT1B than tissues from patients without IBD.


Assuntos
Alquil e Aril Transferases/deficiência , Quimiotaxia de Leucócito , Colite/enzimologia , Colo/enzimologia , Integrinas/metabolismo , Linfócitos T/enzimologia , Proteínas rho de Ligação ao GTP/metabolismo , Imunidade Adaptativa , Alquil e Aril Transferases/genética , Animais , Estudos de Casos e Controles , Células Cultivadas , Colite/genética , Colite/imunologia , Colite/patologia , Colo/imunologia , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Camundongos Knockout , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/patologia , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas rho de Ligação ao GTP/deficiência , Proteínas rho de Ligação ao GTP/genética
17.
Mediators Inflamm ; 2019: 2056085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360118

RESUMO

Colitis-associated colorectal cancer (CRC) development has been shown to be related to chronically enhanced inflammation. Macrophage migration inhibitory factor (MIF) is an inflammatory mediator that favors inflammatory cytokine production and has chemotactic properties for the recruitment of macrophages (Møs) and T cells. Here, we investigated the role of MIF in the inflammatory response and recruitment of immune cells in a murine model of chemical carcinogenesis to establish the impact of MIF on CRC genesis and malignancy. We used BALB/c MIF-knockout (MIF-/-) and wild-type (WT) mice to develop CRC by administering intraperitoneal (i.p.) azoxymethane and dextran sodium sulfate in drinking water. Greater tumor burdens were observed in MIF-/- mice than in WT mice. Tumors from MIF-/- mice were histologically identified to be more aggressive than tumors from WT mice. The localization of MIF suggests that it is also involved in cell differentiation. The relative gene expression of il-17, measured by real-time PCR, was higher in MIF-/- CRC mice, compared to the WT CRC and healthy MIF-/- mice. Importantly, compared to the WT intestinal epithelium, lower percentages of tumor-associated Møs were found in the MIF-/- intestinal epithelium. These results suggest that MIF plays a role in controlling the initial development of CRC by attracting Møs to the tumor, which is a condition that favors the initial antitumor responses.


Assuntos
Colite/metabolismo , Colite/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos/metabolismo , Linfócitos T/metabolismo , Animais , Progressão da Doença , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Fatores Inibidores da Migração de Macrófagos/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout
18.
EBioMedicine ; 45: 495-510, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31253515

RESUMO

BACKGROUND: Ulcerative Colitis (UC) is an Inflammatory Bowel Disease (IBD) characterized by uncontrolled immune response, diarrhoea, weight loss and bloody stools, where sustained remission is not currently achievable. Dextran Sulphate Sodium (DSS)-induced colitis is an animal model that closely mimics human UC. Ultrasound (US) has been shown to prevent experimental acute kidney injury through vagus nerve (VN) stimulation and activation of the cholinergic anti-inflammatory pathway (CAIP). Since IBD patients may present dysfunctional VN activity, our aim was to determine the effects of therapeutic ultrasound (TUS) in DSS-induced colitis. METHODS: Acute colitis was induced by 2% DSS in drinking water for 7 days and TUS was administered to the abdominal area for 7 min/day from days 4-10. Clinical symptoms were analysed, and biological samples were collected for proteomics, macroscopic and microscopic analysis, flow cytometry and immunohistochemistry. FINDINGS: TUS attenuated colitis by reducing clinical scores, colon shortening and histological damage, inducing proteomic tolerogenic response in the gut during the injury phase and early recovery of experimental colitis. TUS did not improve clinical and pathological outcomes in splenectomised mice, while α7nAChR (α7 nicotinic acetylcholine receptor - indicator of CAIP involvement) knockout animals presented with disease worsening. Increased levels of colonic F4/80+α7nAChR+ macrophages in wild type mice suggest CAIP activation. INTERPRETATION: These results indicate TUS improved DSS-induced colitis through stimulation of the splenic nerve along with possible contribution by VN with CAIP activation. FUND: Intramural Research Programs of the Clinical Centre, the National Institute of Biomedical Imaging and Bioengineering at the NIH and CAPES/Brazil.


Assuntos
Colite/terapia , Inflamação/terapia , Doenças Inflamatórias Intestinais/terapia , Terapia por Ultrassom , Animais , Colite/induzido quimicamente , Colite/patologia , Citocinas/genética , Citocinas/efeitos da radiação , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Macrófagos/efeitos da radiação , Camundongos , Camundongos Knockout , Peroxidase/química , Proteômica , Receptor Nicotínico de Acetilcolina alfa7/genética
19.
J Ethnopharmacol ; 241: 112008, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31158441

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The use of nutraceutical-based products has increased in recent years due to their demonstrated efficacy and their good safety profile. Onion is one of the most commonly used plants in the traditional medicine for the management of various conditions including inflammatory and gastrointestinal diseases. However, little is known regarding the molecular mechanism of the anti-inflammatory effects of onion particularly in inflammatory bowel disease (IBD). AIM OF THE STUDY: To test the anti-inflammatory effects of onion bulb extract (OBE) in an IBD mouse model and the molecular mechanisms responsible for these effects such as modulation of the expression and/or the activity profile of various pro-inflammatory molecules. MATERIALS AND METHODS: Colitis was induced in mice by dextran sulfate sodium (DSS) daily administration for 5 days. Animals were sacrificed, colons were removed and the severity of the inflammation was determined by the gross and histological assessments. The colonic level/activity of various cytokines and chemokines were measured using proteome profiling-based assay, western blotting, and immunofluorescence techniques. RESULTS: DSS-induced colitis was significantly reduced by the daily OBE treatment and 5-aminosalicylic acid (5-ASA, positive control), particularly at 100-200 mg/kg doses, at both the gross and histological levels. OBE was also shown to reduce colonic expression and activity of several pro-inflammatory molecules and signaling pathways, such as mitogen activated protein kinase family, mammalian target of rapamycin, cyclooxygenase-2, and tissue inhibitors of metalloproteinases. In addition, OBE reduced the expression of interferon-γ, various C-C and C-X-C chemokines, and molecules involved in the apoptotic machinery such as cytochrome c, caspase-3 and -8, B-cell lymphoma-extra-large and -2. CONCLUSIONS: OBE showed anti-inflammatory actions in IBD mouse model, which is attributed, in part, to the modulation of the expression and the activity of important pro-inflammatory molecules and signaling pathways involved in the inflammatory response. These data suggest that OBE may be a promising lead in the therapeutic management of IBD.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Cebolas , Extratos Vegetais/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Citocinas/imunologia , Sulfato de Dextrana , Camundongos Endogâmicos BALB C , Raízes de Plantas
20.
Appl Microbiol Biotechnol ; 103(15): 6169-6186, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165225

RESUMO

Ulcerative colitis (UC) is a chronic relapsing disease. Treatment of UC would benefit from specific targeting of therapeutics to the intestine. Previous studies have demonstrated that bovine lactoferricin and lactoferrampin have bactericidal, anti-inflammatory, and immunomodulatory effects. Here, we investigated whether oral administration of a bovine lactoferricin-lactoferrampin (LFCA)-encoding Lactococcus lactis (LL-LFCA) strain could alleviate experimental colitis. LFCA derived from LL-LFCA inhibited the growth of Escherichia coli and Staphylococcus aureus in vitro. In mice, administration of LL-LFCA decreased the disease activity index and attenuated dextran sulfate sodium (DSS)-induced body weight loss and colon shortening. LL-LFCA treatment also ameliorated DSS-induced colon damage, inhibited inflammatory cell infiltration, significantly decreased myeloperoxidase activity, and ameliorated DSS-induced disruption of intestinal permeability and tight junctions. In addition, 16S rDNA sequencing showed that LL-LFCA reversed DSS-induced gut dysbiosis. The production of proinflammatory mediators in serum and the colon was also reduced by administration of LL-LFCA. In vitro, LFCA derived from LL-LFCA decreased the messenger RNA expression of proinflammatory factors. The underlying mechanisms may involve inhibition of the nuclear factor kappa B (NF-κB) pathway. The results demonstrate that LL-LFCA ameliorates DSS-induced intestinal injury in mice, suggesting that LL-LFCA might be an effective drug for the treatment of inflammatory bowel diseases.


Assuntos
Antibacterianos/metabolismo , Colite/patologia , Colite/terapia , Lactococcus lactis/metabolismo , Lactoferrina/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/metabolismo , Animais , Colite/induzido quimicamente , Modelos Animais de Doenças , Disbiose/terapia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Microbioma Gastrointestinal/efeitos dos fármacos , Lactococcus lactis/genética , Lactococcus lactis/crescimento & desenvolvimento , Lactoferrina/genética , Camundongos , Fragmentos de Peptídeos/genética , Proteínas Recombinantes/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Resultado do Tratamento
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