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1.
J Biol Chem ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988243

RESUMO

Glucocorticoids are potent endogenous anti-inflammatory molecules, and their cognate receptor, glucocorticoid receptor (GR), is expressed in nearly all immune cells. Macrophages are heterogeneous immune cells having a central role in both tissue homeostasis and inflammation and also play a role in the pathogenesis of some inflammatory diseases. Paradoxically, glucocorticoids have only a limited efficacy in controlling the resolution of these macrophage-related diseases. Here, we report that the transcriptomes of monocyte-like THP-1 cells and macrophage-like THP-1 cells (THP1-MΦ) have largely conserved gene expression patterns. In contrast, the differentiation to THP1-MΦ significantly altered the sensitivity of gene transcription to glucocorticoids. Among glucocorticoid-regulated genes, we identified the exopeptidase dipeptidyl peptidase-4 (DPP4) as a critical glucocorticoid-responsive gene in THP1-MΦ. We found that GR directly induces DPP4 gene expression by binding to two glucocorticoid-responsive elements (GREs) within the DPP4 promoter. Additionally, we show that glucocorticoid-induced DPP4 expression is blocked by the GR antagonist RU-486 and by GR siRNA transfection and that DPP4 enzyme activity is reduced by DPP4 inhibitors. Of note, glucocorticoids highly stimulated macrophage mobility; unexpectedly, DPP4 mediated the glucocorticoid-induced macrophage migration, and siRNA-mediated knockdowns of GR and DPP4 blocked dexamethasone-induced THP1-MΦ migration. Moreover, glucocorticoid-induced DPP4 activation was also observed in proinflammatory M1-polarized murine macrophages, as well as peritoneal macrophages, and was associated with increased macrophage migration. Our results indicate that glucocorticoids directly up-regulate DPP4 expression and thereby induce migration in macrophages, potentially explaining why glucocorticoid therapy is less effective in controlling macrophage-dominated inflammatory disorders.

2.
Front Immunol ; 10: 2449, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824476

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by mucosa damage associated with an uncontrolled inflammatory response. This immunological impairment leads to altered inflammatory mediators such as IL-33, which is shown to increase in the mucosa of active UC (aUC) patients. MicroRNAs present a distorted feature in inflamed colonic mucosa and are potential IL-33 regulating candidates in UC. Therefore, we studied the microRNA and mRNA profiles in inflamed colonic samples of UC patients, evaluating the effect of a microRNA (selected by in silico analysis and its expression in UC patients), on IL-33 under inflammatory conditions. We found that inflamed mucosa (n = 8) showed increased expression of 40 microRNAs and 2,120 mRNAs, while 49 microRNAs and 1,734 mRNAs were decreased, as determined by microarrays. In particular, IL-33 mRNA showed a 3.8-fold increase and eight members of a microRNA family (miR-378), which targets IL-33 mRNA in the 3'UTR, were decreased (-3.9 to -3.0 times). We selected three members of the miR-378 family (miR-378a-3p, miR-422a, and miR-378c) according to background information and interaction energy analysis, for further correlation analyses with IL-33 expression through qPCR and ELISA, respectively. We determined that aUC (n = 24) showed high IL-33 levels, and decreased expression of miR-378a-3p and miR-422a compared to inactive UC (n = 10) and controls (n = 6). Moreover, both microRNAs were inversely correlated with IL-33 expression, while miR-378c does not show a significant difference. To evaluate the effect of TNFα on the studied microRNAs, aUC patients with anti-TNF therapy were compared to aUC receiving other treatments. The levels of miR-378a-3p and miR-378c were higher in aUC patients with anti-TNF. Based on these findings, we selected miR-378a-3p to exploring the molecular mechanism involved by in vitro assays, showing that over-expression of miR-378a-3p decreased the levels of an IL-33 target sequence ß-gal-reporter gene in HEK293 cells. Stable miR-378a-3p over-expression/inhibition inversely modulated IL-33 content and altered viability of HT-29 cells. Additionally, in an inflammatory context, TNFα decreased miR-378a-3p levels in HT-29 cells enhancing IL-33 expression. Together, our results propose a regulatory mechanism of IL-33 expression exerted by miR-378a-3p in an inflammatory environment, contributing to the understanding of UC pathogenesis.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31377809

RESUMO

OBJECTIVES: Xerostomia in SS patients has been associated with low quality and quantity of salivary mucins, which are fundamental for the hydration and protection of the oral mucosa. The aim of this study was to evaluate if cytokines induce aberrant mucin expression and whether tauroursodeoxycholic acid (TUDCA) is able to counteract such an anomaly. METHODS: Labial salivary glands from 16 SS patients and 15 control subjects, as well as 3D acini or human submandibular gland cells stimulated with TNF-α or IFN-γ and co-incubated with TUDCA, were analysed. mRNA and protein levels of Mucin 1 (MUC1) and MUC7 were determined by RT-qPCR and western blot, respectively. Co-immunoprecipitation and immunofluorescence assays for mucins and GRP78 [an endoplasmic reticulum (ER)-resident protein] were also performed. mRNA levels of RelA/p65 (nuclear factor-κB subunit), TNF-α, IL-1ß, IL-6, SEL1L and EDEM1 were determined by RT-qPCR, and RelA/p65 localization was evaluated by immunofluorescence. RESULTS: MUC1 is overexpressed and accumulated in the ER of labial salivary gland from SS patients, while MUC7 accumulates throughout the cytoplasm of acinar cells; however, MUC1, but not MUC7, co-precipitated with GRP78. TUDCA diminished the overexpression and aberrant accumulation of MUC1 induced by TNF-α and IFN-γ, as well as the nuclear translocation of RelA/p65, together with the expression of inflammatory and ER stress markers in 3D acini. CONCLUSION: Chronic inflammation alters the secretory process of MUC1, inducing ER stress and affecting the quality of saliva in SS patients. TUDCA showed anti-inflammatory properties decreasing aberrant MUC1 accumulation. Further studies are necessary to evaluate the potential therapeutic effect of TUDCA in restoring glandular homeostasis in SS patients.

6.
Front Immunol ; 10: 1394, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281317

RESUMO

In colorectal cancer (CRC), cancer-associated fibroblasts (CAFs) are the most abundant component from the tumor microenvironment (TM). CAFs facilitate tumor progression by inducing angiogenesis, immune suppression and invasion, thus altering the organization/composition of the extracellular matrix (i.e., desmoplasia) and/or activating epithelial-mesenchymal transition (EMT). Soluble factors from the TM can also contribute to cell invasion through secretion of cytokines and recently, IL-33/ST2 pathway has gained huge interest as a protumor alarmin, promoting progression to metastasis by inducing changes in TM. Hence, we analyzed IL-33 and ST2 content in tumor and healthy tissue lysates and plasma from CRC patients. Tissue localization and distribution of these molecules was evaluated by immunohistochemistry (using localization reference markers α-smooth muscle actin or α-SMA and E-cadherin), and clinical/histopathological information was obtained from CRC patients. In vitro experiments were conducted in primary cultures of CAFs and normal fibroblasts (NFs) isolated from tumor and healthy tissue taken from CRC patients. Additionally, migration and proliferation analysis were performed in HT29 and HCT116 cell lines. It was found that IL-33 content increases in left-sided CRC patients with lymphatic metastasis, with localization in tumor epithelia associated with abundant desmoplasia. Although ST2 content showed similarities between tumor and healthy tissue, a decreased immunoreactivity was observed in left-sided tumor stroma, associated to metastasis related factors (advanced stages, abundant desmoplasia, and presence of tumor budding). A principal component analysis (including stromal and epithelial IL-33/ST2 and α-SMA immunoreactivity with extent of desmoplasia) allowed us to distinguish clusters of low, intermediate and abundant desmoplasia, with potential to develop a diagnostic signature with benefits for further therapeutic targets. IL-33 transcript levels from CAFs directly correlated with CRC cell line migration induced by CAFs conditioned media, with rhIL-33 inducing a mesenchymal phenotype in HT29 cells. These results indicate a role of IL-33/ST2 in tumor microenvironment, specifically in the interaction between CAFs and epithelial tumor cells, thus contributing to invasion and metastasis in left-sided CRC, most likely by activating desmoplasia.

7.
Front Immunol ; 10: 277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30915065

RESUMO

Ulcerative colitis (UC) and Crohn's disease (CD), collectively known as Inflammatory Bowel Diseases (IBD), are caused by a complex interplay between genetic, immunologic, microbial and environmental factors. Dysbiosis of the gut microbiome is increasingly considered to be causatively related to IBD and is strongly affected by components of a Western life style. Bacteria that ferment fibers and produce short chain fatty acids (SCFAs) are typically reduced in mucosa and feces of patients with IBD, as compared to healthy individuals. SCFAs, such as acetate, propionate and butyrate, are important metabolites in maintaining intestinal homeostasis. Several studies have indeed shown that fecal SCFAs levels are reduced in active IBD. SCFAs are an important fuel for intestinal epithelial cells and are known to strengthen the gut barrier function. Recent findings, however, show that SCFAs, and in particular butyrate, also have important immunomodulatory functions. Absorption of SCFAs is facilitated by substrate transporters like MCT1 and SMCT1 to promote cellular metabolism. Moreover, SCFAs may signal through cell surface G-protein coupled receptors (GPCRs), like GPR41, GPR43, and GPR109A, to activate signaling cascades that control immune functions. Transgenic mouse models support the key role of these GPCRs in controlling intestinal inflammation. Here, we present an overview of microbial SCFAs production and their effects on the intestinal mucosa with specific emphasis on their relevance for IBD. Moreover, we discuss the therapeutic potential of SCFAs for IBD, either applied directly or by stimulating SCFAs-producing bacteria through pre- or probiotic approaches.

9.
Clin Immunol ; 196: 85-96, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29894742

RESUMO

Here, we determined the 5-hydroxymethylcytosine (5hmC), 5-methylcytosine (5mC), Ten Eleven Translocation (TETs), and DNA methyltransferases (DNMTs) levels in epithelial and inflammatory cells of labial salivary glands (LSG) from Sjögren's syndrome (SS)-patients and the effect of cytokines on HSG cells. LSG from SS-patients, controls and HSG cells incubated with cytokines were analysed. Levels of 5mC, 5hmC, DNMTs, TET2 and MeCP2 were assessed by immunofluorescence. In epithelial cells from SS-patients, an increase in TET2, 5hmC and a decrease in 5mC and MeCP2 were observed, additionally, high levels of 5mC and DNMTs and low levels of 5hmC were detected in inflammatory cells. Cytokines increased TET2 and 5hmC and decreased 5mC levels. Considering that the TET2 gene.promoter contains response elements for transcription factors activated by cytokines, together to in vitro results suggest that changes in DNA hydroxymethylation, resulting from altered levels of TET2 are likely to be relevant in the Sjögren's syndrome etiopathogenesis.


Assuntos
5-Metilcitosina/análogos & derivados , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Proteína 2 de Ligação a Metil-CpG/genética , Proteínas Proto-Oncogênicas/genética , Glândulas Salivares Menores/metabolismo , Síndrome de Sjogren/genética , 5-Metilcitosina/metabolismo , Adulto , Idoso , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Citocinas/imunologia , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/genética , Dioxigenases/imunologia , Dioxigenases/metabolismo , Epigênese Genética , Feminino , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/metabolismo , Lábio , Masculino , Proteína 2 de Ligação a Metil-CpG/metabolismo , Pessoa de Meia-Idade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/imunologia , Oxigenases de Função Mista/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Glândulas Salivares Menores/citologia , Glândulas Salivares Menores/imunologia , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo , Adulto Jovem
10.
Autoimmun Rev ; 17(8): 796-808, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29890347

RESUMO

For many years, researchers in the field of autoimmunity have focused on the role of the immune components in the etiopathogenesis of autoimmune diseases. However, some studies have demonstrated the importance of target tissues in their pathogenesis and the breach of immune tolerance. The immune system as well as target tissue cells (plasmatic, ß-pancreatic, fibroblast-like synoviocytes, thyroid follicular and epithelial cells of the lachrymal glands, salivary glands, intestine, bronchioles and renal tubules) share the characteristic of secretory cells with an extended endoplasmic reticulum (ER). The function of these cells depends considerably on a normal ER function and calcium homeostasis, so they can produce and secrete their main components, which include glycoproteins involved in antigenic presentation such as major histocompatibility complex (MHC) class I and II. All these proteins are synthesized and modified in the ER, and for this reason disturbances in the normal functions of this organelle such as protein folding, protein quality control, calcium homeostasis and redox balance, promote accumulation of unfolded or misfolded proteins, a condition known as ER stress. Autoimmune diseases are characterized by inflammation, which has been associated with an ER stress condition. Interestingly, patients with these diseases contain circulating auto-antibodies against chaperone proteins (such as Calnexin and GRP94), thus affecting the folding and assembly of MHC class I and II glycoproteins and their loading with peptide. The main purpose of this article is to review the involvement of the protein quality control and unfolded protein response (UPR) in the ER protein homeostasis (proteostasis) and their alterations in autoimmune diseases. In addition, we describe the interaction between ER stress and inflammation and evidences are shown of how autoimmune diseases are associated with an ER stress condition, with a special emphasis on the second most prevalent autoimmune rheumatic disease, Sjögren's syndrome.


Assuntos
Autoimunidade , Estresse do Retículo Endoplasmático , Dobramento de Proteína , Proteínas/metabolismo , Síndrome de Sjogren/fisiopatologia , Resposta a Proteínas não Dobradas , Animais , Retículo Endoplasmático/metabolismo , Humanos , Proteínas/química
11.
Rheumatology (Oxford) ; 57(6): 1021-1032, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29534223

RESUMO

Objectives: Labial salivary glands (LSGs) of SS patients show alterations related to endoplasmic reticulum stress. Glandular dysfunction could be partly the consequence of an altered inositol-requiring enzyme 1α (IRE1α)/X box-binding protein 1 (XBP-1) signalling pathway of the unfolded protein response, which then regulates genes involved in biogenesis of the secretory machinery. This study aimed to determine the expression, promoter methylation and localization of the IRE1α/XBP-1 pathway components in LSGs of SS patients and also their expression induced by IFN-γ in vitro. Methods: IRE1α, XBP-1 and glucose-regulated protein 78 (GRP78) mRNA and protein levels were measured by qPCR and western blot, respectively, in LSGs of SS patients (n = 47) and control subjects (n = 37). Methylation of promoters was evaluated by methylation-sensitive high resolution melting, localization was analysed by immunofluorescence and induction of the IRE1α/XBP-1 pathway components by IFN-γ was evaluated in 3D acini. Results: A significant decrease of IRE1α, XBP-1u, XBP-1s, total XBP-1 and GRP78 mRNAs was observed in LSGs of SS patients, which was correlated with increased methylation levels of their respective promoters, and consistently the protein levels for IRE1α, XBP-1s and GRP78 were observed to decrease. IFN-γ decreased the mRNA and protein levels of XBP-1s, IRE1α and GRP78, and increased methylation of their promoters. Significant correlations were also found between IRE1α/XBP-1 pathway components and clinical parameters. Conclusion: Decreased mRNA levels for IRE1α, XBP-1 and GRP78 can be partially explained by hypermethylation of their promoters and is consistent with chronic endoplasmic reticulum stress, which may explain the glandular dysfunction observed in LSGs of SS patients. Additionally, glandular stress signals, including IFN-γ, could modulate the expression of the IRE1α/XBP-1 pathway components.


Assuntos
Endorribonucleases/genética , Regulação da Expressão Gênica , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , Glândulas Salivares/fisiopatologia , Síndrome de Sjogren/genética , Proteína 1 de Ligação a X-Box/genética , Adulto , Idoso , Western Blotting , Metilação de DNA , Estresse do Retículo Endoplasmático , Endorribonucleases/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/biossíntese , Glândulas Salivares/metabolismo , Transdução de Sinais , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Proteína 1 de Ligação a X-Box/biossíntese , Adulto Jovem
12.
World J Gastroenterol ; 23(36): 6628-6638, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29085208

RESUMO

Inflammatory bowel diseases (IBDs), such as ulcerative colitis and Crohn's disease, are chronic pathologies associated with a deregulated immune response in the intestinal mucosa, and they are triggered by environmental factors in genetically susceptible individuals. Exogenous glucocorticoids (GCs) are widely used as anti-inflammatory therapy in IBDs. In the past, patients with moderate or severe states of inflammation received GCs as a first line therapy with an important effectiveness in terms of reduction of the disease activity and the induction of remission. However, this treatment often results in detrimental side effects. This downside drove the development of second generation GCs and more precise (non-systemic) drug-delivery methods. Recent clinical trials show that most of these new treatments have similar effectiveness to first generation GCs with fewer adverse effects. The remaining challenge in successful treatment of IBDs concerns the refractoriness and dependency that some patients encounter during GCs treatment. A deeper understanding of the molecular mechanisms underlying GC response is key to personalizing drug choice for IBDs patients to optimize their response to treatment. In this review, we examine the clinical characteristics of treatment with GCs, followed by an in depth analysis of the proposed molecular mechanisms involved in its resistance and dependence associated with IBDs. This thorough analysis of current clinical and biomedical literature may help guide physicians in determining a course of treatment for IBDs patients and identifies important areas needing further study.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Anti-Inflamatórios/farmacologia , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Doença de Crohn/epidemiologia , Doença de Crohn/genética , Doença de Crohn/imunologia , Sistemas de Liberação de Medicamentos/métodos , Resistência a Medicamentos/genética , Epigênese Genética , Glucocorticoides/farmacologia , Humanos , Sistema Imunitário/efeitos dos fármacos , Imunossupressores/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/fisiopatologia , Prevalência , Resultado do Tratamento
13.
Sci Rep ; 7(1): 10180, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860510

RESUMO

The ST2/IL33 signalling pathway has been associated with ulcerative colitis (UC). ST2, encoded by the IL1RL1 gene, is expressed as both a membrane-anchored receptor (ST2L) activated by IL33 and as a soluble receptor (sST2) with anti-inflammatory properties. In UC patients, sST2 is further increased by corticosteroid treatment; however, the glucocorticoid-mediated molecular regulation remains unknown. We therefore tested whether genetic variants in the IL1RL1 distal promoter are involved in UC and affect glucocorticoid-mediated ST2 expression. Serum ST2 levels and genetic variants in the IL1RL1 distal promoter were examined by ELISA and PCR sequencing in UC patients receiving corticosteroids. Glucocorticoid-mediated ST2 production was evaluated in intestinal mucosa cultures. Molecular regulation of glucocorticoid-mediated ST2 was assessed by RT-qPCR, ChIP assay and luciferase reporter assay. Dexamethasone effect on ST2 transcript expression was analyzed in leukocytes and related to IL1RL1 variants. Sequencing of a distal IL1RL1 promoter region demonstrated that SNPs rs6543115(C) and rs6543116(A) are associated with increased sST2 in UC patients on corticosteroids. Dexamethasone up-regulated sST2 transcription through interaction with the glucocorticoid-response element (GRE) carrying rs6543115(C) variant. Our data indicate that IL1RL1 SNPs rs6543115(C) confer susceptibility to UC and is contained in the GRE, which may modulate glucocorticoid-induced sST2 expression.


Assuntos
Corticosteroides/farmacologia , Colite Ulcerativa/tratamento farmacológico , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Polimorfismo de Nucleotídeo Único , Regulação para Cima , Corticosteroides/uso terapêutico , Adulto , Células Cultivadas , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Predisposição Genética para Doença , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/efeitos dos fármacos , Análise de Sequência de DNA
14.
Rev. méd. Chile ; 145(9): 1129-1136, set. 2017. tab, graf
Artigo em Espanhol | LILACS-Express | ID: biblio-902597

RESUMO

Background: Different strains of invasive Escherichia coli (E. coli), isolated from intestinal mucosa of patients, are related to the pathogenesis of inflammatory bowel diseases (IBD). Aim: To evaluate an association between intracellular E. coli and IBD; its clinical characteristics and use of steroids. Material and Methods: Sixty one patients with Crohn's disease and 83 with ulcerative colitis were studied. To determine the intracellular E. coli content, colonoscopy biopsies of these patients and 29 control subjects were processed using the gentamicin protection assay. Differences in the bacterial content between patient groups were evaluated using Mann-Whitney test, while the association between presence of E. coli with endoscopic activity, location/extension and use of corticosteroid as anti-inflammatory treatment were evaluated with Fisher's exact test or Chi-square test. Results: E. coli strains were detected in 36.1, 39.3 and 10.3% of patients with ulcerative colitis, Crohn's disease and controls, respectively. The number of bacteria per biopsy in Crohn's disease and ulcerative colitis was significantly higher than in controls (p < 0.01 between patients and controls). In ulcerative colitis, significant associations were found between the presence of bacteria and disease location and use of corticosteroids. In Crohn's disease, no association was found. Conclusions: IBD are associated with the presence of intracellular E. coli strains in the intestinal mucosa, suggesting an alteration in the microbiota or loss of integrity of the epithelial barrier. The association of intracellular E. coli with clinical features and the use of corticosteroids in ulcerative colitis suggests that different factors could promote colonization or proliferation of these bacteria.

15.
Rev Med Chil ; 145(9): 1129-1136, 2017 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-29424399

RESUMO

BACKGROUND: Different strains of invasive Escherichia coli (E. coli), isolated from intestinal mucosa of patients, are related to the pathogenesis of inflammatory bowel diseases (IBD). AIM: To evaluate an association between intracellular E. coli and IBD; its clinical characteristics and use of steroids. MATERIAL AND METHODS: Sixty one patients with Crohn's disease and 83 with ulcerative colitis were studied. To determine the intracellular E. coli content, colonoscopy biopsies of these patients and 29 control subjects were processed using the gentamicin protection assay. Differences in the bacterial content between patient groups were evaluated using Mann-Whitney test, while the association between presence of E. coli with endoscopic activity, location/extension and use of corticosteroid as anti-inflammatory treatment were evaluated with Fisher's exact test or Chi-square test. RESULTS: E. coli strains were detected in 36.1, 39.3 and 10.3% of patients with ulcerative colitis, Crohn's disease and controls, respectively. The number of bacteria per biopsy in Crohn's disease and ulcerative colitis was significantly higher than in controls (p < 0.01 between patients and controls). In ulcerative colitis, significant associations were found between the presence of bacteria and disease location and use of corticosteroids. In Crohn's disease, no association was found. CONCLUSIONS: IBD are associated with the presence of intracellular E. coli strains in the intestinal mucosa, suggesting an alteration in the microbiota or loss of integrity of the epithelial barrier. The association of intracellular E. coli with clinical features and the use of corticosteroids in ulcerative colitis suggests that different factors could promote colonization or proliferation of these bacteria.


Assuntos
Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Escherichia coli/isolamento & purificação , Mucosa Intestinal/microbiologia , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Estudos de Casos e Controles , Colite Ulcerativa/tratamento farmacológico , Contagem de Colônia Microbiana , Doença de Crohn/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Estatísticas não Paramétricas , Adulto Jovem
16.
BMC Gastroenterol ; 16: 103, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27565556

RESUMO

BACKGROUND: The ST2/IL-33 pathway has been related to ulcerative colitis (UC), and soluble ST2 (sST2), to disease severity. We tested the potential usefulness of sST2 as a predictive marker of treatment response and patients' outcome. METHODS: Twenty-six patients with active UC were prospectively recruited and grouped according to an endoscopic score and therapy response. Colonoscopic biopsies were collected at baseline and 6 months or when patients showed clinical activity. The protocol was reinitiated in patients requiring rescue therapy. Blood and stool were collected at baseline, 1, 3, 6 and 12 months. Serum and mucosal ST2, and fecal calprotectin (FC) content were determined by ELISA and correlated to Mayo clinical and endoscopic subscore. Intestinal ST2 was evaluated by immunofluorescence. Wilcoxon signed rank test and Spearman correlations (Rs) were applied (p <0.05). RESULTS: Follow-up was completed in 24 patients. sST2 levels (median and range) varied from 173.5 [136.6-274.0] to 86.5 [54.6-133.2] in responders (p < 0.05), and 336.3 [211.0-403.2] to 385.3 pg/mL [283.4-517.3] in non-responders at baseline and 6 months, respectively. sST2 levels correlated with Mayo clinical and endoscopic subscore, mucosal ST2 and FC (Rs = 0.57, 0.66, 0.74 and 0.42, respectively; p < 0.0001) and showed a trend similar to that of FC in responders. Non-responders revealed an increased ST2 content, restricted to the lamina propria's cellular infiltrate. CONCLUSIONS: Consecutive sST2 measurement to follow changes in inflammatory activity of UC patients who respond or not to treatment identifies sST2, like FC, as a useful biomarker in predicting clinical outcome of UC patients.


Assuntos
Colite Ulcerativa/sangue , Colite Ulcerativa/patologia , Proteína 1 Semelhante a Receptor de Interleucina-1/análise , Adulto , Biomarcadores/análise , Biópsia/métodos , Colite Ulcerativa/terapia , Colonoscopia , Ensaio de Imunoadsorção Enzimática , Fezes/química , Feminino , Imunofluorescência , Humanos , Mucosa Intestinal/patologia , Complexo Antígeno L1 Leucocitário/análise , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Estatísticas não Paramétricas
17.
Mol Immunol ; 74: 96-105, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27174187

RESUMO

UNLABELLED: Cardiac inflammation can be produced by pathogen-associated molecular patterns (PAMPs), from parasitic, bacterial or viral origin; or by danger-associated molecular patterns (DAMPs), released from dead cells after cardiac tissue damage, for example by cardiac infarction. Both, PAMPS and DAMPS activate TLR4 on resident immune cells and heart tissue cells, triggering an inflammatory process necessary to begin the wound healing process. Cardiac fibroblasts (CF) are the most abundant cells in the heart and are critical to wound healing, along with cardiac myofibroblasts (CMF), which are differentiated from CF through a TGF-ß1-mediated process. While TLR4 and the inflammasome complex are known to play important roles in CF function, the effects of TGF-ß1 on TLR4 and inflammasome expression and activity remain unknown. To elucidate this important point, we evaluated the effect of TGF-ß1 on TLR4, and the inflammasome protein expression and activity through activation by LPS, mimicking a myocarditis condition by bacterial origin. We found that TGF-ß1 increased TLR4 expression in CF and that the process was mediated by the TGFßRI and p38 signaling pathways. In both CF and CMF, LPS triggered ERK1/2, PI3K-Akt, and p65-NF-κB phosphorylation. All of these effects were blocked by TAK-242, a TLR4 signaling pathway inhibitor. LPS increased pro-IL-1ß levels, which were dependent on the ERK1/2, PI3K-Akt, and NF-κB signaling pathways, and levels were higher in CF than CMF. NLRP3 and ASC levels were similar in CF and CMF, while pro-caspase-1 levels and caspase-1 activity were higher in CMF. LPS+ATP treatment induced inflammasome complex assembly and activation, triggering the release of IL-1ß in both CMF and CF. Finally, the unsecreted pro-IL-1ß in the CF was degraded by autophagy. CONCLUSION: TGF-ß1 increases TLR4 expression in CF. Despite different pro-IL-1ß and caspase-1 activity levels in CF versus CMF, the two cell types secreted similar levels of IL-1ß after LPS+ATP treatment. These findings suggest that both cell types are active participants in inflammation.


Assuntos
Fibroblastos/imunologia , Inflamassomos/imunologia , Interleucina-1beta/biossíntese , Miocárdio/imunologia , Miofibroblastos/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Masculino , Miocárdio/citologia , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley
18.
Cytokine Growth Factor Rev ; 26(6): 615-23, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26271893

RESUMO

IL-33, an IL-1 family member, is expressed by many cell types and can regulate gene transcription. IL-33 is released upon cell necrosis and the precursor form is enzymatically processed, and then drives inflammation as a damage-associated molecular pattern. The IL-33 receptor ST2, encoded by IL1RL1, is expressed as both a membrane-anchored receptor (ST2L) activated by IL-33, and as a soluble variant (sST2) that exhibits anti-inflammatory properties. The IL-33/ST2 axis is involved in the pathogenesis of atopic and autoimmune diseases, cancer, and central nervous system disorders. Here, we review recent findings on the role of the IL-33/ST2 axis in health and disease.


Assuntos
Inflamação/imunologia , Interleucina-33/imunologia , Neoplasias/imunologia , Receptores de Superfície Celular/imunologia , Dermatopatias/imunologia , Animais , Autoimunidade , Humanos , Inflamação/fisiopatologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/fisiopatologia , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33/genética , Interleucina-33/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Dermatopatias/fisiopatologia
19.
Rev Med Virol ; 25(5): 286-99, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26174373

RESUMO

Asp-Glu-Ala-Asp (DEAD)-box polypeptide 3, or DDX3, belongs to the DEAD-box family of ATP-dependent RNA helicases and is known to play different roles in RNA metabolism ranging from transcription to nuclear export, translation, and assembly of stress granules. In addition, there is growing evidence that DDX3 is a component of the innate immune response against viral infections. As such, DDX3 has been shown to play roles both upstream and downstream of I-kappa beta kinase ε (IKKε)/TANK-binding kinase 1, leading to IFN-ß production. Interestingly, several RNA viruses, including human threats such as HIV-1 and hepatitis C virus, hijack DDX3 to accomplish various steps of their replication cycles. Thus, it seems that viruses have evolved to exploit DDX3's functions while threatening the innate immune response. Understanding this interesting dichotomy in DDX3 function will help us not only to improve our knowledge of virus-host interactions but also to develop novel antiviral drugs targeting the multifaceted roles of DDX3 in viral replication.


Assuntos
RNA Helicases DEAD-box/metabolismo , Interações Hospedeiro-Patógeno , Interferon beta/metabolismo , RNA Helicases/metabolismo , Vírus de RNA/imunologia , Vírus de RNA/fisiologia , Replicação Viral , Humanos , Imunidade Inata
20.
Rheumatology (Oxford) ; 54(8): 1518-27, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25802401

RESUMO

OBJECTIVES: A hallmark characteristic of SS patients is the ectopic presence of the mucins MUC5B and MUC7 in the extracellular matrix of salivary glands that have lost apical-basolateral acinar-cell polarity. This study aims to determine whether exogenous salivary mucins induce gene expression of pro-inflammatory cytokines, as well as to evaluate whether the Toll-like receptor-4 (TLR4) pathway is involved in this response. METHODS: Differentiated human submandibular gland (HSG) cells were stimulated with mucins or oligosaccharide residues at different concentrations and for different periods of time. The expression of pro-inflammatory cytokines and their receptors was determined by semi-quantitative real time PCR (sqPCR). TLR4-mediated responses induced by mucin were evaluated with the Toll-IL-1 receptor domain containing adaptor protein (TIRAP) inhibitory peptide or using anti-hTLR4 blocking antibody. TLR4-receptor expression was also determined in SS patients, controls and HSG cells. RESULTS: Mucins induced a significant increase in CXCL8, TNF-α, IFN-α, IFN-ß, IL-6 and IL-1ß, but not B cell activating factor (BAFF). Cytokine induction was mediated by TLR4, as shown using TIRAP or using anti-hTLR4 antibody. Sugar residues present in MUC5B, such as sulpho-Lewis (SO3-3Galß1-3GlcNAc), also induced cytokines. Unexpectedly, mucins induced MUC5B, but not MUC7 expression. CONCLUSION: Salivary mucins were recognized by TLR4 in epithelial cells initiating a pro-inflammatory response that could attract inflammatory cells to amplify and perpetuate inflammation and thereby contribute to the development of a chronic state characteristic of SS. The ectopic localization of MUC5B and MUC7 in the salivary gland extracellular matrix from SS patients and the current results reveal the importance of salivary epithelial cells in innate immunity, as well as in SS pathogenesis.


Assuntos
Citocinas/metabolismo , Inflamação/metabolismo , Mucinas/farmacologia , Síndrome de Sjogren/metabolismo , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Estudos de Casos e Controles , Células Cultivadas , Relação Dose-Resposta a Droga , Matriz Extracelular/metabolismo , Feminino , Humanos , Imunidade Inata/fisiologia , Masculino , Pessoa de Meia-Idade , Mucina-5B/metabolismo , Mucinas/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Transdução de Sinais/fisiologia , Síndrome de Sjogren/patologia , Glândula Submandibular/patologia , Fatores de Tempo
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