Toxin B ofClostridium difficileactivates human VIP submucosal neurons, in part via an IL-1β-dependent pathway

2003 ◽  
Vol 285 (5) ◽  
pp. G1049-G1055 ◽  
Author(s):  
M. Neunlist ◽  
J. Barouk ◽  
K. Michel ◽  
I. Just ◽  
T. Oreshkova ◽  
...  
Keyword(s):  
Mrna Level ◽  
Neuron Specific Enolase ◽  
Human Colon ◽  
Optical Recording ◽  
Enteric Neurons ◽  
Submucosal Plexus ◽  
Excitatory Effect ◽  
Toxin B ◽  
Fos Expression ◽  
Dependent Pathway

This study investigated whether toxin B of Clostridium difficile can activate human submucosal neurons and the involved pathways. Isolated segments of human colon were placed in organ culture for 3 h in the presence of toxin B or IL-1β. Whole mounts of internal submucosal plexus were stained with antibodies against c-Fos, neuron-specific enolase (NSE), vasoactive intestinal polypeptide (VIP), and substance P (SP). The membrane potential (Vm) response of submucosal neurons to local application of toxin B and IL-1β was determined by a multisite optical recording technique. Toxin B (0.1 to 10 ng/ml) increased the proportion of c-Fos-positive neurons dose dependently compared with the control. In the presence of toxin B (10 ng/ml), most c-Fos-positive neurons were immunoreactive for VIP (79.8 ± 22.5%) but only 19.4 ± 14.0% for SP. Toxin B induced a rapid rise in IL-1β mRNA level and a sixfold increase in IL-1β protein in supernatant after 3 h of incubation. c-Fos expression induced by toxin B was reduced dose dependently by IL-1 receptor antagonist (0.1-10 ng/ml). IL-1β significantly increased c-Fos expression in submucosal neurons compared with the control (34.2 ± 10.1 vs. 5.1 ± 1.3% of NSE neurons). Microejection of toxin B had no effect on the Vmof enteric neurons. Evidence of a direct excitatory effect of IL-1β on Vmwas detected in a minority of enteric neurons. Therefore, toxin B of C. difficile activates VIP-positive submucosal neurons, at least in part, via an indirect IL-1β-dependent pathway.

Interleukin-1B (IL-1B) stimulates fos expression in specific subsets of enteric neurons through a cyclooxygenase-dependent pathway

2000 ◽  
Vol 118 (4) ◽  
pp. A710 ◽  
Author(s):  
Joelle M. Bradley ◽  
Eric Ttl Tjwa ◽  
Catherine M. Keenan ◽  
Alfons Ba Kroese ◽  
Keith A. Sharkey
Keyword(s):  
Enteric Neurons ◽  
Fos Expression ◽  
Dependent Pathway

scholarly journals VIP is involved in peripheral CRF-induced stimulation of propulsive colonic motor function and diarrhea in male rats

2018 ◽  
Vol 314 (5) ◽  
pp. G610-G622 ◽  
Author(s):  
Seiichi Yakabi ◽  
Lixin Wang ◽  
Hiroshi Karasawa ◽  
Pu-Qing Yuan ◽  
Kazuhiko Koike ◽  
...  
Keyword(s):  
Vasoactive Intestinal Peptide ◽  
Motor Function ◽  
Terminal Ileum ◽  
Proximal Colon ◽  
Corticotropin Releasing Factor ◽  
Submucosal Plexus ◽  
Myenteric Neurons ◽  
Colonic Motor ◽  
Fos Expression ◽  
Stimulation Of

We investigated whether vasoactive intestinal peptide (VIP) and/or prostaglandins contribute to peripheral corticotropin-releasing factor (CRF)-induced CRF1 receptor-mediated stimulation of colonic motor function and diarrhea in rats. The VIP antagonist, [4Cl-D-Phe6, Leu17]VIP injected intraperitoneally completely prevented CRF (10 µg/kg ip)-induced fecal output and diarrhea occurring within the first hour after injection, whereas pretreatment with the prostaglandins synthesis inhibitor, indomethacin, had no effect. In submucosal plexus neurons, CRF induced significant c-Fos expression most prominently in the terminal ileum compared with duodenum and jejunum, whereas no c-Fos was observed in the proximal colon. c-Fos expression in ileal submucosa was colocalized in 93.4% of VIP-positive neurons and 31.1% of non-VIP-labeled neurons. CRF1 receptor immunoreactivity was found on the VIP neurons. In myenteric neurons, CRF induced only a few c-Fos-positive neurons in the ileum and a robust expression in the proximal colon (17.5 ± 2.4 vs. 0.4 ± 0.3 cells/ganglion in vehicle). The VIP antagonist prevented intraperitoneal CRF-induced c-Fos induction in the ileal submucosal plexus and proximal colon myenteric plexus. At 60 min after injection, CRF decreased VIP levels in the terminal ileum compared with saline (0.8 ± 0.3 vs. 2.5 ± 0.7 ng/g), whereas VIP mRNA level detected by qPCR was not changed. These data indicate that intraperitoneal CRF activates intestinal submucosal VIP neurons most prominently in the ileum and myenteric neurons in the colon. It also implicates VIP signaling as part of underlying mechanisms driving the acute colonic secretomotor response to a peripheral injection of CRF, whereas prostaglandins do not play a role. NEW & NOTEWORTHY Corticotropin-releasing factor (CRF) in the gut plays a physiological role in the stimulation of lower gut secretomotor function induced by stress. We showed that vasoactive intestinal peptide (VIP)-immunoreactive neurons in the ileal submucosal plexus expressed CRF1 receptor and were prominently activated by CRF, unlike colonic submucosal neurons. VIP antagonist abrogated CRF-induced ileal submucosal and colonic myenteric activation along with functional responses (defecation and diarrhea). These data point to VIP signaling in ileum and colon as downstream effectors of CRF.

scholarly journals Fidaxomicin and OP-1118 Inhibit Clostridium difficile Toxin A- and B-Mediated Inflammatory Responses via Inhibition of NF-κB Activity

2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Hon Wai Koon ◽  
Jiani Wang ◽  
Caroline C. Mussatto ◽  
Christina Ortiz ◽  
Elaine C. Lee ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Intestinal Inflammation ◽  
Inflammatory Responses ◽  
Human Colon ◽  
Toxin A ◽  
Primary Metabolite ◽  
Necrosis Factor Alpha ◽  
Toxin B ◽  
Content Type ◽  
Tnf Α

ABSTRACTClostridium difficilecauses diarrhea and colitis by releasing toxin A and toxin B. In the human colon, both toxins cause intestinal inflammation and stimulate tumor necrosis factor alpha (TNF-α) expression via the activation of NF-κB. It is well established that the macrolide antibiotic fidaxomicin is associated with reduced relapses ofC. difficileinfection. We showed that fidaxomicin and its primary metabolite OP-1118 significantly inhibited toxin A-mediated intestinal inflammation in micein vivoand toxin A-induced cell roundingin vitro. We aim to determine whether fidaxomicin and OP-1118 possess anti-inflammatory effects against toxin A and toxin B in the human colon and examine the mechanism of this response. We used fresh human colonic explants, NCM460 human colonic epithelial cells, and RAW264.7 mouse macrophages to study the mechanism of the activity of fidaxomicin and OP-1118 against toxin A- and B-mediated cytokine expression and apoptosis. Fidaxomicin and OP-1118 dose-dependently inhibited toxin A- and B-induced TNF-α and interleukin-1β (IL-1β) mRNA expression and histological damage in human colonic explants. Fidaxomicin and OP-1118 inhibited toxin A-mediated NF-κB phosphorylation in human and mouse intestinal mucosae. Fidaxomicin and OP-1118 also inhibited toxin A-mediated NF-κB phosphorylation and TNF-α expression in macrophages, which was reversed by the NF-κB activator phorbol myristate acetate (PMA). Fidaxomicin and OP-1118 prevented toxin A- and B-mediated apoptosis in NCM460 cells, which was reversed by the addition of PMA. PMA reversed the cytoprotective effect of fidaxomicin and OP-1118 in toxin-exposed human colonic explants. Fidaxomicin and OP-1118 inhibitC. difficiletoxin A- and B-mediated inflammatory responses, NF-κB phosphorylation, and tissue damage in the human colon.

scholarly journals Changes in Immunoreactivity of Sensory Substances within the Enteric Nervous System of the Porcine Stomach during Experimentally Induced Diabetes

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Michał Bulc ◽  
Katarzyna Palus ◽  
Jarosław Całka ◽  
Łukasz Zielonka
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
Porcine Model ◽  
Enteric Neurons ◽  
Submucosal Plexus ◽  
Chemical Coding ◽  
Chemically Induced ◽  
Calcitonin Gene ◽  
Enteric Plexus ◽  
Clear Increase

One of the most frequently reported disorders associated with diabetes is gastrointestinal (GI) disturbance. Although pathogenesis of these complications is multifactorial, the complicity of the enteric nervous system (ENS) in this respect has significant importance. Therefore, this paper analysed changes in substance P- (SP-), calcitonin gene-related peptide- (CGRP-), and leu5-enkephalin- (L-ENK-) like immunoreactivity (LI) in enteric stomach neurons caused by chemically induced diabetes in a porcine model. Using double immunofluorescent labelling, it was found that acute hyperglycaemia led to significant changes in the chemical coding of stomach enteric neurons. Generally, the response to artificially inducted diabetes depended on the “kind” of enteric plexus as well as the stomach region studied. A clear increase in the percentage of neurons immunoreactive to SP and CGRP was visible in the myenteric plexus (MP) in the antrum, corpus, and pylorus as well as in the submucosal plexus (SmP) in the corpus. For L-ENK, an increase in the number of L-ENK-LI neurons was observed in the MP of the antrum and SmP in the corpus, while in the MP of the corpus and pylorus, a decrease in the percentage of L-ENK-LI neurons was noted.

scholarly journals Quantitative analysis of the level of p53 and p21(WAF1) mRNA in human colon cancer HT-29 cells treated with inositol hexaphosphate.

2006 ◽  
Vol 53 (2) ◽  
pp. 349-356 ◽  
Author(s):  
Ludmiła Weglarz ◽  
Izabela Molin ◽  
Arkadiusz Orchel ◽  
Beata Parfiniewicz ◽  
Zofia Dzierzewicz
Keyword(s):  
Cell Cycle ◽  
Colon Cancer ◽  
Cell Cycle Progression ◽  
Mrna Level ◽  
Human Colon ◽  
Human Colon Cancer ◽  
Cycle Progression ◽  
Inositol Hexaphosphate ◽  
P21 Waf1 ◽  
Ht 29

The aim of this study was to analyze the molecular mechanism of inositol hexaphosphate (InsP(6)) action through which it may inhibit proliferation of colon cancer cells and cell cycle progression. A kinetic study of p53 and p21(WAF1) mRNA increase was performed on human colon cancer HT-29 cells after treatment with 1, 5 and 10 mM InsP(6) for 6, 12, 24 and 48 h. Real-time-QPCR based on TaqMan methodology was applied to analyze quantitatively the transcript levels of these genes. The transcription of beta-actin and GAPDH genes was assessed in parallel to select the control gene with least variability. The 2(-Delta Delta Ct) method was used to analyze the relative changes in gene transcription. InsP(6) stimulated p53 and p21(WAF1) expression at the mRNA level, with the highest increase in p21(WAF1) mRNA occurring at 24 h, i.e., following the highest increase in p53 mRNA observed at 12 h. Based on these studies it may be concluded that the ability of InsP(6) to arrest the cell cycle may be mediated by the transcriptional up-regulation of the p53-responsive p21(WAF1) gene.

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