scholarly journals Role of the Helicobacter hepaticus Flagellar Sigma Factor FliA in Gene Regulation and Murine Colonization

2008 ◽  
Vol 190 (19) ◽  
pp. 6398-6408 ◽  
Author(s):  
Torsten Sterzenbach ◽  
Lucie Bartonickova ◽  
Wiebke Behrens ◽  
Birgit Brenneke ◽  
Jessika Schulze ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Sigma Factor ◽  
Intestinal Inflammation ◽  
Gall Stone ◽  
Helicobacter Hepaticus ◽  
Intestinal Colonization ◽  
Wild Type ◽  
Chronic Intestinal Inflammation ◽  
Flagellar Genes

ABSTRACT The enterohepatic Helicobacter species Helicobacter hepaticus colonizes the murine intestinal and hepatobiliary tract and is associated with chronic intestinal inflammation, gall stone formation, hepatitis, and hepatocellular carcinoma. Thus far, the role of H. hepaticus motility and flagella in intestinal colonization is unknown. In other, closely related bacteria, late flagellar genes are mainly regulated by the sigma factor FliA (σ28). We investigated the function of the H. hepaticus FliA in gene regulation, flagellar biosynthesis, motility, and murine colonization. Competitive microarray analysis of the wild type versus an isogenic fliA mutant revealed that 11 genes were significantly more highly expressed in wild-type bacteria and 2 genes were significantly more highly expressed in the fliA mutant. Most of these were flagellar genes, but four novel FliA-regulated genes of unknown function were identified. H. hepaticus possesses two identical copies of the gene encoding the FliA-dependent major flagellin subunit FlaA (open reading frames HH1364 and HH1653). We characterized the phenotypes of mutants in which fliA or one or both copies of the flaA gene were knocked out. flaA_1 flaA_2 double mutants and fliA mutants did not synthesize detectable amounts of FlaA and possessed severely truncated flagella. Also, both mutants were nonmotile and unable to colonize mice. Mutants with either flaA gene knocked out produced flagella morphologically similar to those of wild-type bacteria and expressed FlaA and FlaB. flaA_1 mutants which had flagella but displayed reduced motility did not colonize mice, indicating that motility is required for intestinal colonization by H. hepaticus and that the presence of flagella alone is not sufficient.

Role of CD5 expression on TCRγδ T cell-differentiation and development of chronic intestinal inflammation

2001 ◽  
Vol 120 (5) ◽  
pp. A517-A517
Author(s):  
A MIZOGUCHI ◽  
E MIZOGUCHI ◽  
Y DEJONG ◽  
H TAKEDATSU ◽  
F PREFFER ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
T Cell ◽  
Intestinal Inflammation ◽  
T Cell Differentiation ◽  
Chronic Intestinal Inflammation

scholarly journals Smad7 and Colorectal Carcinogenesis: A Double-Edged Sword

Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 612 ◽  
Author(s):  
Edoardo Troncone ◽  
Giovanni Monteleone
Keyword(s):  
Immune Cells ◽  
Transforming Growth Factor ◽  
Intestinal Inflammation ◽  
Association Studies ◽  
Cell Subset ◽  
Colorectal Carcinogenesis ◽  
Genome Wide Association Studies ◽  
Nucleotide Polymorphisms ◽  
Chronic Intestinal Inflammation

Colorectal carcinogenesis is a complex process in which many immune and non-immune cells and a huge number of mediators are involved. Among these latter factors, Smad7, an inhibitor of the transforming growth factor (TGF)-β1 signaling that has been involved in the amplification of the inflammatory process sustaining chronic intestinal inflammation, is supposed to make a valid contribution to the growth and survival of colorectal cancer (CRC) cells. Smad7 is over-expressed by tumoral cells in both sporadic CRC and colitis-associated CRC, where it sustains neoplastic processes through activation of either TGFβ-dependent or non-dependent pathways. Consistently, genome-wide association studies have identified single nucleotide polymorphisms of the Smad7 gene associated with CRC and shown that either amplification or deletion of the Smad7 gene associates with a poor prognosis or better outcome, respectively. On the other hand, there is evidence that over-expression of Smad7 in immune cells infiltrating the inflamed gut of patients with inflammatory bowel disease can elicit anti-tumor responses, with the down-stream effect of attenuating CRC cell growth. Taken together, these observations suggest a double role of Smad7 in colorectal carcinogenesis, which probably depends on the cell subset and the biological context analyzed. In this review, we summarize the available evidences about the role of Smad7 in both sporadic and colitis-associated CRC.

scholarly journals Unique Role of Caffeine Compared to Other Methylxanthines (Theobromine, Theophylline, Pentoxifylline, Propentofylline) in Regulation of AD Relevant Genes in Neuroblastoma SH-SY5Y Wild Type Cells

2020 ◽  
Vol 21 (23) ◽  
pp. 9015
Author(s):  
Daniel Janitschke ◽  
Anna A. Lauer ◽  
Cornel M. Bachmann ◽  
Martin Seyfried ◽  
Heike S. Grimm ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Transcriptional Regulation ◽  
Expression Patterns ◽  
Wild Type ◽  
Neuronal Function ◽  
Purine Base ◽  
Unique Role ◽  
Beneficial Effects ◽  
Other Substances

Methylxanthines are a group of substances derived from the purine base xanthine with a methyl group at the nitrogen on position 3 and different residues at the nitrogen on position 1 and 7. They are widely consumed in nutrition and used as pharmaceuticals. Here we investigate the transcriptional regulation of 83 genes linked to Alzheimer’s disease in the presence of five methylxanthines, including the most prominent naturally occurring methylxanthines—caffeine, theophylline and theobromine—and the synthetic methylxanthines pentoxifylline and propentofylline. Methylxanthine-regulated genes were found in pathways involved in processes including oxidative stress, lipid homeostasis, signal transduction, transcriptional regulation, as well as pathways involved in neuronal function. Interestingly, multivariate analysis revealed different or inverse effects on gene regulation for caffeine compared to the other methylxanthines, which was further substantiated by multiple comparison analysis, pointing out a distinct role for caffeine in gene regulation. Our results not only underline the beneficial effects of methylxanthines in the regulation of genes in neuroblastoma wild-type cells linked to neurodegenerative diseases in general, but also demonstrate that individual methylxanthines like caffeine mediate unique or inverse expression patterns. This suggests that the replacement of single methylxanthines by others could result in unexpected effects, which could not be anticipated by the comparison to other substances in this substance class.

scholarly journals The Dual Role of Nod-Like Receptors in Mucosal Innate Immunity and Chronic Intestinal Inflammation

2014 ◽  
Vol 5 ◽  
Author(s):  
Daniele Corridoni ◽  
Kristen O. Arseneau ◽  
Maria Grazia Cifone ◽  
Fabio Cominelli
Keyword(s):  
Innate Immunity ◽  
Intestinal Inflammation ◽  
Dual Role ◽  
Chronic Intestinal Inflammation

scholarly journals Going Beyond Bacteria: Uncovering the Role of Archaeome and Mycobiome in Inflammatory Bowel Disease

2021 ◽  
Vol 12 ◽  
Author(s):  
Yashar Houshyar ◽  
Luca Massimino ◽  
Luigi Antonio Lamparelli ◽  
Silvio Danese ◽  
Federica Ungaro
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Intestinal Inflammation ◽  
The Body ◽  
Inflammatory Conditions ◽  
Relapsing Remitting ◽  
Health And Disease ◽  
Inflammatory Bowel ◽  
Chronic Intestinal Inflammation

Inflammatory Bowel Disease (IBD) is a multifaceted class of relapsing-remitting chronic inflammatory conditions where microbiota dysbiosis plays a key role during its onset and progression. The human microbiota is a rich community of bacteria, viruses, fungi, protists, and archaea, and is an integral part of the body influencing its overall homeostasis. Emerging evidence highlights dysbiosis of the archaeome and mycobiome to influence the overall intestinal microbiota composition in health and disease, including IBD, although they remain some of the least understood components of the gut microbiota. Nonetheless, their ability to directly impact the other commensals, or the host, reasonably makes them important contributors to either the maintenance of the mucosal tissue physiology or to chronic intestinal inflammation development. Therefore, the full understanding of the archaeome and mycobiome dysbiosis during IBD pathogenesis may pave the way to the discovery of novel mechanisms, finally providing innovative therapeutic targets that can soon implement the currently available treatments for IBD patients.

scholarly journals Commensal-derived succinate enhances tuft cell specification and suppresses ileal inflammation

2019 ◽  
Author(s):  
Amrita Banerjee ◽  
Charles A. Herring ◽  
Hyeyon Kim ◽  
Bob Chen ◽  
Alan J. Simmons ◽  
...  
Keyword(s):  
Intestinal Inflammation ◽  
Genetic Model ◽  
Cell Lineage ◽  
Inverse Correlation ◽  
Tca Cycle ◽  
Cell Hyperplasia ◽  
Cell Specification ◽  
Tuft Cell ◽  
Chronic Intestinal Inflammation

Longitudinal analysis of Crohn's disease (CD) incidence has identified an inverse correlation with helminth infestation and recent studies have revealed that intestinal tuft cell hyperplasia is critical for helminth response. Tuft cell frequency was decreased in the inflamed ilea of CD patients and a mouse model of TNFα-induced Crohn's-like ileitis (TNFΔARE). Single-cell RNA sequencing paired with unbiased differential trajectory analysis of the tuft cell lineage in a genetic model of tuft cell hyperplasia (AtohKO) demonstrated that the tuft cell lineage had increased tricarboxylic acid (TCA) cycle gene signatures. Commensal microbiome-derived succinate was detected in the ileal lumen of these animals while microbiome depletion suppressed tuft cell hyperplasia. Therapeutic succinate treatment in TNFΔARE animals reduced pathology in correlation with induced tuft cell specification. We provide evidence implicating the modulatory role of intestinal tuft cells in chronic intestinal inflammation, which could facilitate leveraging this rare and elusive cell type for CD treatment.

scholarly journals High-Fat Diet Promotes DSS-Induced Ulcerative Colitis by Downregulated FXR Expression through the TGFB Pathway

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Di Zhao ◽  
Chenwen Cai ◽  
Qiyi Chen ◽  
Shuang Jin ◽  
Bo Yang ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
High Fat Diet ◽  
Target Genes ◽  
Intestinal Inflammation ◽  
Farnesoid X Receptor ◽  
Mucosal Barrier ◽  
High Fat ◽  
Colon Rectal Cancer ◽  
Chronic Intestinal Inflammation

Ulcerative colitis is one of the IBD which cause a chronic intestinal inflammation and dysfunctional of the mucosal barrier. For now, the incident of UC was steadily increased all over the world. It has become a novel independent risk factor of several severe diseases especially colon-rectal cancer. However, the etiology of UC was still obscure. Previous studies show that high-fat diet contributed to the pathogenesis of immune system dysregulation, and farnesoid X receptor (FXR) was also implicated in the pathogenesis of various inflammatory symptoms. Yet, their inner roles in the pathogenesis of UC have not been mentioned. In this study, we aim to investigate the role of FXR in UC. High-fat diet (HFD) promotes the progression of DSS-induced UC, shows an increasing secretion of bile acid in serum, and leads to a downregulation of FXR target genes (FXRα, Shp, and lbabp). Adding FXR agonist FexD rescues the phenotype induced by high-fat diet, whereas TGFBRI inhibitor SB431542 abrogates the restoration by FexD in DSS-induced UC mice. To further verify the relationship between the FXR and TGFB signaling pathway, we made a UC-HFD model in the Caco2 cell line. Results shows the same conclusion that FXR mitigate UC inflammation through a TGFB-dependent pathway. These results expand the role of FXR in ulcerative colitis and suggest that FXR activation may be considered a therapeutic strategy for UC.

scholarly journals Analysis of Gene Expression in Ceca of Helicobacter hepaticus-Infected A/JCr Mice before and after Development of Typhlitis

2003 ◽  
Vol 71 (7) ◽  
pp. 3885-3893 ◽  
Author(s):  
Matthew H. Myles ◽  
Robert S. Livingston ◽  
Beth A. Livingston ◽  
Jennifer M. Criley ◽  
Craig L. Franklin
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Intestinal Inflammation ◽  
Adaptive Immune System ◽  
Gamma Interferon ◽  
Helicobacter Hepaticus ◽  
Abnormal Immune Response ◽  
Inflammatory Bowel ◽  
Immune Related Genes ◽  
Chronic Intestinal Inflammation

ABSTRACT The inflammatory bowel diseases, Crohn's disease and ulcerative colitis, are chronic inflammatory disorders of the gastrointestinal tract. The causes of these diseases remain unknown; however, prevailing theories suggest that chronic intestinal inflammation results from a dysregulated immune response to ubiquitous bacterial antigens. While a substantial body of data has been amassed describing the role of the adaptive immune system in perpetuating and sustaining inflammation, very little is known about the early signals, prior to the development of inflammation, that initiate and direct the abnormal immune response. To this end, we characterized the gene expression profile of A/JCr mice with Helicobacter hepaticus-induced typhlitis at month 1 of infection, prior to the onset of histologic disease, and month 3 of infection, after chronic inflammation is fully established. Analysis of the gene expression in ceca of H. hepaticus infected mice revealed 25 up-regulated and 3 down-regulated genes in the month-1 postinoculation group and 31 up-regulated and 2 down-regulated genes in the month-3 postinoculation group. Among these was a subset of immune-related genes, including interferon-inducible protein 10, monokine induced by gamma interferon, macrophage-induced protein 1 alpha, and serum amyloid A1. Semiquantitative real-time reverse transcriptase PCR confirmed the increased expression levels of these genes, as well as elevated expression of gamma interferon. To our knowledge, this is the first report profiling cecal gene expression in H. hepaticus-infected A/JCr mice. The findings of altered gene expression prior to the development of any features of pathology and the ensuing chronic disease course make this an attractive model for studying early host response to microbe-induced inflammatory bowel disease.

Sign in / Sign up

Export Citation Format

Share Document