1,721,034 research outputs found
IBD risk loci are enriched in multigenic regulatory modules encompassing putative causative genes
GWAS have identified >200 risk loci for Inflammatory Bowel Disease (IBD). The majority of disease associations are known to be driven by regulatory variants. To identify the putative causative genes that are perturbed by these variants, we generate a large transcriptome data set (nine disease-relevant cell types) and identify 23,650 cis-eQTL. We show that these are determined by ∼9720 regulatory modules, of which ∼3000 operate in multiple tissues and ∼970 on multiple genes. We identify regulatory modules that drive the disease association for 63 of the 200 risk loci, and show that these are enriched in multigenic modules. Based on these analyses, we resequence 45 of the corresponding 100 candidate genes in 6600 Crohn disease (CD) cases and 5500 controls, and show with burden tests that they include likely causative genes. Our analyses indicate that ≥10-fold larger sample sizes will be required to demonstrate the causality of individual genes using this approach. © 2018 The Author(s)
Macrophage Activation in Pediatric Nonalcoholic Fatty Liver Disease (NAFLD) Correlates with Hepatic Progenitor Cell Response via Wnt3a Pathway
Non-alcoholic fatty liver disease is one of the most important causes of liver-related morbidity in children. In non-alcoholic fatty liver disease, the activation of liver resident macrophage pool is a central event in the progression of liver injury. The aims of the present study were to evaluate the polarization of liver macrophages and the possible role of Wnt3a production by macrophages in hepatic progenitor cell response in the progression of pediatric nonalcoholic fatty liver disease. 32 children with biopsy-proven non-alcoholic fatty liver disease were included. 20 out of 32 patients were treated with docosahexaenoic acid for 18 months and biopsies at the baseline and after 18 months were included. Hepatic progenitor cell activation, macrophage subsets and Wnt/β-catenin pathway were evaluated by immunohistochemistry and immunofluorescence. Our results indicated that in pediatric non-alcoholic fatty liver disease, pro-inflammatory macrophages were the predominant subset. Macrophage polarization was correlated with Non-alcoholic fatty liver disease Activity Score, ductular reaction, and portal fibrosis; docosahexaenoic acid treatment determined a macrophage polarization towards an anti-inflammatory phenotype in correlation with the reduction of serum inflammatory cytokines, with increased macrophage apoptosis, and with the upregulation of macrophage Wnt3a expression; macrophage Wnt3a expression was correlated with β-catenin phosphorylation in hepatic progenitor cells and signs of commitment towards hepatocyte fate. In conclusion, macrophage polarization seems to have a key role in the progression of pediatric non-alcoholic fatty liver disease; the modulation of macrophage polarization could drive hepatic progenitor cell response by Wnt3a production. © 2016 Carpino et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
LPS-induced TNF-α factor mediates pro-inflammatory and pro-fibrogenic pattern in non-alcoholic fatty liver disease
Lipopolysaccharide (LPS) is currently considered one of the major players in non-alcoholic fatty liver disease (NAFLD) pathogenesis and progression. Here, we aim to investigate the possible role of LPS-induced TNF-α factor (LITAF) in inducing a pro-inflammatory and pro-fibrogenic phenotype of non-alcoholic steatohepatitis (NASH). We found that children with NAFLD displayed, in different liver-resident cells, an increased expression of LITAF which correlated with histological traits of hepatic inflammation and fibrosis. Total and nuclear LITAF expression increased in mouse and human hepatic stellate cells (HSCs). Moreover, LPS induced LITAF-dependent transcription of IL-1ß, IL-6 and TNF-α in the clonal myofibroblastic HSC LX-2 cell line, and this effect was hampered by LITAF silencing. We showed, for the first time in HSCs, that LITAF recruitment to these cytokine promoters is LPS dependent. However, preventing LITAF nuclear translocation by p38MAPK inhibitor, the expression of IL-6 and TNF-α was significantly reduced with the aid of p65NF-κB, while IL-1ß transcription exclusively required LITAF expression/activity. Finally, IL-1ß levels in plasma mirrored those in the liver and correlated with LPS levels and LITAF-positive HSCs in children with NASH. In conclusion, a more severe histological profile in paediatric NAFLD is associated with LITAF over-expression in HSCs, which in turn correlates with hepatic and circulating IL-1ß levels outlining a panel of potential biomarkers of NASH-related liver damage. The in vitro study highlights the role of LITAF as a key regulator of the LPS-induced pro-inflammatory pattern in HSCs and suggests p38MAPK inhibitors as a possible therapeutic approach against hepatic inflammation in NASH
Lactobacillus reuteri ATCC55730 in cystic fibrosis
Objectives: The aim of this study was to evaluate in patients with cystic fibrosis (CF) the effect of Lactobacillus reuteri (LR) on the rate of respiratory exacerbations and of the infections of both upper respiratory and gastrointestinal tracts. METHODS: Prospective randomized, double-blind, placebo-controlled study enrolling 61 patients with CF with mild-to-moderate lung disease at the Regional Center for CF of the Department of Pediatrics, University of Rome "La Sapienza." All of the patients were not hospital inpatients at the time of the enrollment. Inclusion criteria were forced expiratory volume in the first second (FEV1) >70% predicted; no inhaled or systemic steroids, no anti-inflammatory drugs, antileukotrienes, and mast cell membrane stabilizers; and no serious organ involvement. Exclusion criteria were a history of pulmonary exacerbation or upper respiratory infection in the previous 2 months; changes in medications in the last 2 months; a history of hemoptysis in the last 2 months; and colonization with Burkholderia cepacia or mycobacteria. Patients were randomly assigned to receive LR (30 patients) in 5 drops per day (10 colony-forming units) or placebo (31 patients) for 6 months. Main outcomes were number of episodes of pulmonary exacerbations and hospital admissions for pulmonary exacerbations, number of gastrointestinal and upper respiratory tract infections. FEV1, fecal calprotectin, and cytokine profile in induced sputum and plasma were assessed at baseline and at the end of the trial. RESULTS: Pulmonary exacerbations were significantly reduced in the LR group compared with the placebo group (P<0.01; odds ratio 0.06 [95% confidence interval {CI} 0-0.40]; number needed to treat 3 [95% CI 2-7]). Similarly, the number of upper respiratory tract infections (in our series only otitis) was significantly reduced in the LR group compared with the placebo group (P<0.05; odds ratio 0.14 [95% CI 0-0.96]; number needed to treat 6 [95% CI 3-102]). The 2 groups did not differ statistically in the mean number and duration of hospitalizations for pulmonary exacerbations and gastrointestinal infections. There was no significant statistical difference in the mean delta value of FEV1, fecal calprotectin concentration, and tested cytokines (tumor necrosis factor-? and interleukin-8) between the 2 groups. CONCLUSIONS: LR reduces pulmonary exacerbations and upper respiratory tract infections in patients with CF with mild-to-moderate lung disease. LR administration may have a beneficial effect on the disease course of CF. ᄅ 2013 by European Society for Pediatric Gastroenterology,Hepatology, and Nutrition and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition
The Identification and Pharmacological Characterization of 6-(tert-Butylsulfonyl)-N-(5-fluoro-1H-indazol-3-yl)quinolin-4-amine (GSK583), a Highly Potent and Selective Inhibitor of RIP2 Kinase
RIP2 kinase is a central component of the innate immune system and enables downstream signaling following activation of the pattern recognition receptors NOD1 and NOD2, leading to the production of inflammatory cytokines. Recently, several inhibitors of RIP2 kinase have been disclosed that have contributed to the fundamental understanding of the role of RIP2 in this pathway. However, because they lack either broad kinase selectivity or strong affinity for RIP2, these tools have only limited utility to assess the role of RIP2 in complex environments. We present, herein, the discovery and pharmacological characterization of GSK583, a next-generation RIP2 inhibitor possessing exquisite selectivity and potency. Having demonstrated the pharmacological precision of this tool compound, we report its use in elucidating the role of RIP2 kinase in a variety of in vitro, in vivo, and ex vivo experiments, further clarifying our understanding of the role of RIP2 in NOD1 and NOD2 mediated disease pathogenesis. © 2016 American Chemical Society
Associations between Genetic Polymorphisms in IL-33, IL1R1 and Risk for Inflammatory Bowel Disease
Background: Recent evidence suggests that the IL-33/IL1RL1 axis plays a critical role in several autoimmune and inflammatory disorders; however, its mechanistic role in inflammatory bowel disease (IBD) has not been clearly defined. We investigated the contribution of IL-33 and IL1RL1 polymorphisms to IBD risk, and possible correlations with phenotype in an Italian cohort of adult and pediatric patients. Methods: We evaluated the association of six SNPs in IL-33 and IL1RL1 genes, in 805 Crohn's disease (CD), 816 ulcerative colitis (UC), and 752 controls, using Taqman. IL-33 and IL1RL1 mRNA expression was also analyzed. Results: Significant allele and genotype associations with IL-33 rs3939286 were found in CD (P = 0.004; P = 0.035) and UC patients (P = 0.002; P = 0.038). After stratifying the cohort for age at diagnosis, the differences remained significant only in the IBD adult-onset. Significant associations were also obtained in CD patients with two IL1RL1 polymorphisms (rs13015714 and rs2058660, P<0.015). By combining homo- and heterozygous carriers of the rs13015714 risk allele, differences were still significant for both CD adult- and pediatric-onset. Upon genotype-phenotype evaluation, an increased frequency of extensive colitis in adult UC (P = 0.019) and in steroid-responsive pediatric patients (P = 0.024) carrying the IL-33 rs3939286 risk genotype, was observed. mRNA expression of IL-33 and IL1RL1 in inflamed IBD biopsy samples was significantly increased. Conclusions: Common IL-33 and IL1RL1 polymorphisms contribute to the risk of IBD in an Italian cohort of adult and pediatric patients, with some influence on sub-phenotypes. © 2013 Latiano et al
Recent advances in understanding the role of adipocytokines during non-alcoholic fatty liver disease pathogenesis and their link with hepatokines
Non-alcoholic fatty liver disease (NAFLD) is currently considered the main cause of chronic liver disease worldwide. Mechanisms leading to the development and progression of this disease are topics of great interest for researchers and clinicians. The current multi-hit hypothesis has thrown the crosstalk between liver and adipose tissue into sharp focus. It is well known that adipose tissue produces circulating factors, known as adipocytokines, which exert several effects on liver cells, promoting the onset of NAFLD and its progression to non-alcoholic steatohepatitis in obese subjects. In a similar way, hepatocytes may also respond to obesogenic stimuli by producing and releasing hepatokines into the circulation. Here, the authors provide an overview of recent advances in our understanding of the role of the most relevant adipocytokines and hepatokines in NAFLD pathogenesis, highlighting their possible molecular and functional interactions. © 2015 Taylor & Francis
Advances in the medical management of paediatric IBD
IBD includes two classic entities, Crohn's disease and ulcerative colitis, and a third undetermined form (IBD-U), characterized by a chronic relapsing course resulting in a high rate of morbidity and impaired quality of life. Children with IBD are vulnerable in terms of growth failure, malnutrition and emotional effects. The aims of therapy have now transitioned from symptomatic control to the achievement of mucosal healing and deep remission. This type of therapy has been made possible by the advent of disease-modifying drugs, such as biologic agents, which are capable of interrupting the inflammatory cascade underlying IBD. Biologic agents are generally administered in patients who are refractory to conventional therapies. However, there is growing support that such agents could be used in the initial phases of the disease, typically in paediatric patients, to interrupt and cease the inflammatory process. Until several years ago, most therapeutic programmes in paediatric patients with IBD were borrowed from adult trials, whereas paediatric studies were often retrospective and uncontrolled. However, guidelines on therapeutic management of paediatric IBD and controlled, prospective, randomized trials including children with IBD have now been published. Here, the current knowledge concerning treatment options for children with IBD are reported. We also highlight the effectiveness and safety of new therapeutic advances in these paediatric patients.© 2014 Macmillan Publishers Limited. All rights reserved
Lactoferrin prevents invasion and inflammatory response following E. coli strain LF82 infection in experimental model of Crohn's disease
Background: Crohn's disease is a multifactorial disease in which an aberrant immune response to commensal intestinal microbiota leads to chronic inflammation. The small intestine of patients with Crohn's disease is colonized by a group of adherent-invasive Escherichia coli strongly able to adhere and invade intestinal epithelial cells lactoferrin is an iron-binding glycoprotein known to have anti-bacterial and anti-inflammatory activities. Aims: We explore the ability of bovine lactoferrin to modulate the interactions between the adherent-invasive E. coli strain LF82 and intestinal epithelial cells as well as the inflammatory response. Methods: Bacterial adhesion and invasion assays were used to assess the antimicrobial activity of lactoferrin. Electron microscopy was used to characterize bacteria-cell interactions. The mRNA expression of pro-inflammatory cytokines was measured both in cultured cells and in biopsies taken from intestine of patients affected by Crohn's disease. Results: Lactoferrin inhibited bacterial invasion through minimally affecting adhesion. This divergence was due to a mannose-dependent lactoferrin binding to the bacterial type 1 pili and consequent bacterial aggregation on the intestinal epithelial cell surface. Expression of pro-inflammatory cytokines, such as TNF-alpha, IL-8, and IL-6, was markedly inhibited by lactoferrin both in cultured and Crohn-derived intestinal cells. Conclusions: Bovine lactoferrin might function via an antibacterial and/or anti-inflammatory mechanism in the treatment of Crohn's disease. © 2014 Editrice Gastroenterologica Italiana S.r.l
Role of HMGB1 as a suitable biomarker of subclinical intestinal inflammation and mucosal healing in patients with inflammatory bowel disease
Background: Noninvasive biomarkers of high- and low-grade intestinal inflammation and of mucosal healing (MH) in patients with inflammatory bowel disease are currently lacking. We have recently shown that fecal high mobility group box 1 (HMGB1) protein is a novel biomarker of gut inflammation. We aimed at investigating in a mouse model if HMGB1 was able to foresee both a clinically evident and a subclinical gut inflammation and if its normalization indicated MH. We also aimed at confirming the results in patients with Crohn's disease (CD) and ulcerative colitis. Methods: C57BL6/J mice were treated with increasing doses of dextran sodium sulphate to induce colitis of different severity degrees; 28 with CD, 23 with ulcerative colitis, and 17 controls were also enrolled. Fecal HMGB1 was analyzed by enzyme-linked immunosorbent assay and immunoblotting. Results: Fecal HMGB1 increased by 5-, 11-, 18-, and 24-folds with dextran sodium sulphate doses of 0.25%, 0.50%, 1%, and 4%, respectively, showing that the protein detected a high-grade and a subclinical inflammation. After a recovery time of 4-week posttreatment, HMGB1 returned to control levels, paralleling MH. In patients, fecal HMGB1 significantly correlated with endoscopic indexes (Simple Endoscopic Score for Crohn's Disease [SES-CD], endoscopic Mayo subscore), but not with the disease activity indexes (Crohn's disease Activity Index, partial Mayo score). Conclusions: Fecal HMGB1 is a robust noninvasive biomarker of clinically overt and subclinical gut inflammation; it can also be a surrogate marker of MH. We suggest the use of fecal HMGB1 to monitor the disease course and assess therapy outcomes in inflammatory bowel disease. Copyright © 2014 Crohn's & Colitis Foundation of America, Inc
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