scholarly journals Helicobacter hepaticus Induce Colitis in Male IL-10−/− Mice Dependent by Cytolethal Distending Toxin B and via the Activation of Jak/Stat Signaling Pathway

Author(s):  
Liqi Zhu ◽  
Chen Zhu ◽  
Shuyang Cao ◽  
Quan Zhang

It has been well documented that cytolethal distending toxin (CDT) from Helicobacter hepaticus (H. hepaticus), Campylobacter jejuni (C. jejuni) and other Gram-negative intestinal pathogens is linked to the inflammatory bowel disease (IBD). However, the mechanisms underlying the progression of H. hepaticus induced colitis remains unclear. In this study, male B6.129P2-IL10tm1Cgn/J mice were infected by H. hepaticus and ΔCdtB H. hepaticus for 6, 12, 18, and 24 weeks. Histopathology, H. hepaticus colonization levels, expression of inflammatory cytokines, signaling pathways, and content of NO in proximal colon were examined. We found that Cytolethal distending toxin subunit B (CdtB) deletion had no influence on colonization ability of H. hepaticus in colon of B6.129P2-IL10tm1cgn/J mice, and there was no significant difference in abundance of colonic H. hepaticus over infection duration. H. hepaticus aggravated rectocele and proximal colonic inflammation, especially at 24 WPI, while ΔCdtB H. hepaticus could not cause significant symptom. Furthermore, mRNA levels of Il-6, Tnf-α, Il-1β, and iNOS significantly increased in the proximal colon of H. hepaticus-infected mice compared to ΔCdtB H. hepaticus infected group from 12 WPI to 24 WPI. In addition, the elevated content of NO and activated Stat3 and Jak2 in colon were observed in H. hepaticus infected mice. These data demonstrated that CdtB promote colitis development in male B6.129P2-IL10tm1Cgn/J mice by induction of inflammatory response and activation of Jak-Stat signaling pathway.

2020 ◽  
Vol 22 (1) ◽  
pp. 364
Author(s):  
Qiyuan Han ◽  
Thomas J. Y. Kono ◽  
Charles G. Knutson ◽  
Nicola M. Parry ◽  
Christopher L. Seiler ◽  
...  

Epigenetic dysregulation is hypothesized to play a role in the observed association between inflammatory bowel disease (IBD) and colon tumor development. In the present work, DNA methylome, hydroxymethylome, and transcriptome analyses were conducted in proximal colon tissues harvested from the Helicobacter hepaticus (H. hepaticus)-infected murine model of IBD. Reduced representation bisulfite sequencing (RRBS) and oxidative RRBS (oxRRBS) analyses identified 1606 differentially methylated regions (DMR) and 3011 differentially hydroxymethylated regions (DhMR). These DMR/DhMR overlapped with genes that are associated with gastrointestinal disease, inflammatory disease, and cancer. RNA-seq revealed pronounced expression changes of a number of genes associated with inflammation and cancer. Several genes including Duox2, Tgm2, Cdhr5, and Hk2 exhibited changes in both DNA methylation/hydroxymethylation and gene expression levels. Overall, our results suggest that chronic inflammation triggers changes in methylation and hydroxymethylation patterns in the genome, altering the expression of key tumorigenesis genes and potentially contributing to the initiation of colorectal cancer.


2021 ◽  
pp. 1-21
Author(s):  
Masoud Neshan ◽  
Seyed Kazem Malakouti ◽  
Leila Kamalzadeh ◽  
Mina Makvand ◽  
Arezoo Campbell ◽  
...  

Background: Late-onset Alzheimer’s disease (LOAD) is associated with many environmental and genetic factors. The effect of systemic inflammation on the pathogenesis of neurodegenerative diseases such as AD has been strongly suggested. T helper cells (Th) are one of the important components of the immune system and can easily infiltrate the brain in pathological conditions. The development of each Th-subset depends on the production of unique cytokines and their main regulator. Objective: This study aimed to compare the mRNA levels of Th-related genes derived from peripheral blood mononuclear cells of LOAD patients with control. Also, the identification of the most important Th1/Th2 genes and downstream pathways that may be involved in the pathogenesis of AD was followed by computational approaches. Methods: This study invloved 30 patients with LOAD and 30 non-demented controls. The relative expression of T-cell cytokines (IFN-γ, TNF-α, IL-4, and IL-5) and transcription factors (T-bet and GATA-3) were assessed using real-time PCR. Additionally, protein-protein interaction (PPI) was investigated by gene network construction. Results: A significant decrease at T-bet, IFN-γ, TNF-α, and GATA-3 mRNA levels was detected in the LOAD group, compared to the controls. However, there was no significant difference in IL-4 or IL-5 mRNA levels. Network analysis revealed a list of the highly connected protein (hubs) related to mitogen-activated protein kinase (MAPK) signaling and Th17 cell differentiation pathways. Conclusion: The findings point to a molecular dysregulation in Th-related genes, which can promising in the early diagnosis or targeted interventions of AD. Furthermore, the PPI analysis showed that upstream off-target stimulation may involve MAPK cascade activation and Th17 axis induction.


2005 ◽  
Vol 73 (6) ◽  
pp. 3559-3567 ◽  
Author(s):  
Zhongming Ge ◽  
Yan Feng ◽  
Mark T. Whary ◽  
Prashant R. Nambiar ◽  
Shilu Xu ◽  
...  

ABSTRACT Helicobacter hepaticus, which induces chronic hepatitis and typhlocolitis in susceptible mouse strains, produces a cytolethal distending toxin (CDT) consisting of CdtA, CdtB, and CdtC. A cdtB-deficient H. hepaticus isogenic mutant (HhcdtBm7) was generated and characterized for colonization parameters in four intestinal regions (jejunum, ileum, cecum, and colon) of outbred Swiss Webster (SW) mice. Inactivation of the cdtB gene abolished the ability of HhcdtBm7 to colonize female mice at both 8 and 16 weeks postinfection (wpi), whereas HhcdtBm7 colonized all of four intestinal regions of three of five males at 8 wpi and then was eliminated by 16 wpi. Wild-type (WT) H. hepaticus was detected in the corresponding intestinal regions of both male and female mice at 8 and 16 wpi; however, colonization levels of WT H. hepaticus in the cecum and colon of male mice were approximately 1,000-fold higher than in females (P < 0.0079) at 16 wpi. Infection with WT H. hepaticus, but not HhcdtBm7, at 8 wpi was associated with significantly increased mRNA level of ileal and cecal gamma interferon (IFN-γ) in females (P < 0.016 and 0.031 between WT H. hepaticus-infected and sham-dosed females, respectively). In contrast, the mRNA levels of IFN-γ were significantly higher in the colon (P < 0.0079) and trended to be higher in the cecum (P < 0.15) in the HhcdtBm7-colonized male mice versus the sham-dosed controls at 8 wpi. In addition, mRNA levels of ileal IFN-γ were significantly higher in the control females than males at 8 wpi (P < 0.016). There were significantly higher Th1-associated immunoglobulin G2a (IgG2a), Th2-associated IgG1 and mucosal IgA (P < 0.002, 0.002, 0.002, respectively) responses in the mice infected with WT H. hepaticus when compared to HhcdtBm7 at 16 wpi. Colonic interleukin-10 (IL-10) expressions at 16 wpi were significantly lower in both female and male mice colonized by WT H. hepaticus or in males transiently colonized through 8 wpi by HhcdtBm7 versus control mice (P < 0.0159). These lines of evidence indicate that (i) H. hepaticus CDT plays a crucial role in the persistent colonization of H. hepaticus in SW mice; (ii) SW female mice are more resistant to H. hepaticus colonization than male mice; (iii) there was persistent colonization of WT H. hepaticus in cecum, colon, and jejunum but only transient colonization of H. hepaticus in the ileum of female mice; (iv) H. hepaticus colonization was associated with down-regulation of colonic IL-10 production.


2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Zhipeng Hu ◽  
Maoyi Yang ◽  
Qiaobo Ye ◽  
Kaihua Qin ◽  
Mingquan Wu ◽  
...  

The incidence of inflammatory bowel disease (IBD), which predominantly comprises Crohn’s disease and ulcerative colitis, is increasing worldwide. However, the treatment of IBD still faces great challenges. The involved NF-κB is the main signaling pathway in human IBD and thus is a prime target. There is abundant evidence that Tou Nong San (TNS), which is a traditional Chinese medicinal decoction used for treating sores and carbuncles, has a positive effect on the inflammation. This study investigated the effects of oral administration of TNS on colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) and the underlying mechanism(s). Quality control of the major compounds in TNS was performed by high-performance liquid chromatography, and six chemical constituents were identified in aqueous extracts. TNS led to improvements in weight loss and water and food intake in rats. The macroscopic and microscopic scores of rat tissues greatly decreased. Protein and mRNA levels of proinflammatory cytokines, including interleukin-17 (IL-17), tumour necrosis factor-α, IL-1β, and IL6, involved in the NF-κB signaling pathway were greatly reduced. The results suggest that the anti-inflammatory effect of TNS is associated with the regulation of the NF-κB signaling pathway, which contributes to the network pharmacological effect of TNS on human IBD in clinical practice.


2005 ◽  
Vol 73 (2) ◽  
pp. 912-920 ◽  
Author(s):  
Jeremy A. Peña ◽  
Arlin B. Rogers ◽  
Zhongming Ge ◽  
Vivian Ng ◽  
Sandra Y. Li ◽  
...  

ABSTRACT Clinical and experimental evidence has demonstrated the potential role of probiotics in the prevention or treatment of inflammatory bowel disease. Probiotic clones with direct immunomodulatory activity may have anti-inflammatory effects in the intestine. We investigated the roles of tumor necrosis factor alpha (TNF-α)-inhibitory Lactobacillus clones with a pathogen-induced murine colitis model. Murine-derived probiotic lactobacilli were selected in vitro for their ability to inhibit TNF-α secretion by Helicobacter hepaticus-stimulated macrophages. Interleukin-10 (IL-10)-deficient mice were treated with probiotic Lactobacillus reuteri in combination with Lactobacillus paracasei and then challenged with H. hepaticus. Ten weeks postinoculation, the severity of typhlocolitis was assessed by histologic examination of the cecocolic region. Intestinal proinflammatory cytokine responses were evaluated by real-time quantitative reverse transcriptase PCR and immunoassays, and the quantities of intestinal H. hepaticus were evaluated by real-time PCR. Intestinal colonization by TNF-α-inhibitory lactobacilli reduced intestinal inflammation in H. hepaticus-challenged IL-10-deficient mice despite similar quantities of H. hepaticus in cocolonized animals. Proinflammatory colonic cytokine (TNF-α and IL-12) levels were lowered in Lactobacillus-treated animals. In this H. hepaticus-challenged IL-10-deficient murine colitis model, lactobacilli demonstrated probiotic effects by direct modulation of mucosal inflammatory responses.


Pancreatology ◽  
2017 ◽  
Vol 17 (3) ◽  
pp. S120
Author(s):  
Rita Lippai ◽  
Erna Sziksz ◽  
Domonkos Pap ◽  
Réka Rokonay ◽  
Apor Veres-Székely ◽  
...  

Biomedicines ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 514
Author(s):  
Jennifer R. Matthews ◽  
Lakshini Y. Herat ◽  
Aaron L. Magno ◽  
Shelley Gorman ◽  
Markus P. Schlaich ◽  
...  

Recent preclinical data show that sodium glucose cotransporter 2 (SGLT2) inhibitors are able to reduce weight gain and induce beiging in white adipose tissue (WAT). We have previously shown that in neurogenic hypertensive Schlager (BPH/2J) mice, treatment with the SGLT2 inhibitor, Dapagliflozin, reduced blood pressure and prevented weight gain. Here we show that chemical sympathetic denervation achieved by systemic administration of 6-hydroxy-dopamine (6-OHDA) reduces body weight and the heightened sympathetic nervous system (SNS) innervation in WAT. Furthermore, we demonstrate that 2 weeks of Dapagliflozin treatment increases SNS innervation in WAT of hypertensive mice. This increase is accompanied by a non-significant elevation in mRNA levels of the Ucp1 and Pgc-1α genes, which are markers of beiging. No significant difference in the mRNA levels of the inflammatory mediators Il-6 and Tnf-α were detected in WAT of Dapagliflozin treated mice. These findings suggest that SGLT-2 inhibitor-associated prevention of weight gain may be mediated, at least in part, by inducing the beiging of WAT.


2001 ◽  
Vol 69 (7) ◽  
pp. 4232-4241 ◽  
Author(s):  
Marika C. Kullberg ◽  
Antonio Gigliotti Rothfuchs ◽  
Dragana Jankovic ◽  
Patricia Caspar ◽  
Thomas A. Wynn ◽  
...  

ABSTRACT We have previously shown that specific-pathogen-free interleukin-10 (IL-10)-deficient (IL-10 KO) mice reconstituted withHelicobacter hepaticus develop severe colitis associated with a Th1-type cytokine response. In the present study, we formally demonstrate that IL-12 is crucial for disease induction, because mice deficient for both IL-10 and IL-12 p40 show no intestinal pathology following H. hepaticus infection. By using monoclonal antibodies (MAbs) to IL-12, gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α), we have further analyzed the role of these cytokines in the maintenance of the Th1 response and inflammation in IL-10 KO mice with established H. hepaticus-induced colitis. Treatment of infected colitic IL-10 KO mice with anti-IL-12 p40 resulted in markedly reduced intestinal inflammation, colonic IFN-γ, TNF-α, and inducible nitric oxide synthase (iNOS) mRNA levels, and H. hepaticus-specific IFN-γ secretion by mesenteric lymph node (MLN) cells compared to the findings in control MAb-treated mice. Moreover, the diminished pathology was associated with decreased numbers of colonic CD3+ T cells and significantly reduced frequencies ofHelicobacter-reactive CD4+ Th1 cells in MLN. In contrast, anti-IFN-γ and/or anti-TNF-α had no effect on intestinal inflammation in IL-10 KO mice with established colitis. Using IL-10/IFN-γ double-deficient mice, we further show that IFN-γ is not required for the development of colitis follwing H. hepaticus infection. MLN cells from infected IL-10/IFN-γ KO animals secreted elevated amounts of IL-12 and TNF-α following bacterial antigen stimulation, indicating alternative pathways of disease induction. Taken together, our results demonstrate a crucial role for IL-12 in both inducing and sustaining intestinal inflammation through recruitment and maintenance of a pool of pathogenic Th1 cells.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Sheyda Damoogh ◽  
Mehrad Vosough ◽  
Shima Hadifar ◽  
Masoumeh Rasoli ◽  
Ali Gorjipour ◽  
...  

Abstract Objective Gut-microbiota plays key roles in many aspects like the health and illness of humans. It's well proved that modification of gut microbiota by probiotics is useful for improving inflammatory bowel disease (IBD) conditions. According to recent studies, different types of bacterial metabolites can affect immune cells and inflammation conditions. The present study aimed to evaluate the anti-inflammatory effects of metabolites of E. coli Nissle1917. Results The cell-free supernatant could modulate TNF-α production and affected many crucial mediators in the Toll-like receptor (TLR) signaling pathway. Also, supernatant showed significant dose-dependent properties in this regard. In this study, the TLR signaling pathway was found among probable mechanisms by which probiotics can affect inflammatory situations. These findings provide additional evidence on the use of probiotic metabolites for inhibiting and down-regulating numerous key mediator factors in the TLR signaling pathway. Aberrant or dysfunctional TLR signaling contributes to the development of acute and chronic intestinal inflammatory pathways in IBD. Therefore, finding a component that can affect this process might be considered for therapeutic targets in IBD patients.


Author(s):  
Jafar Karami ◽  
Elham Farhadi ◽  
Ali-Akbar Delbandi ◽  
Mehdi Shekarabi ◽  
Mohammad Naghi Tahmasebi ◽  
...  

Fibroblast-like synoviocytes (FLSs) produce lots of inflammatory molecules that trigger immune responses and intensification the inflammation and thereby play important roles in Rheumatoid Arthritis )RA( pathogenesis. Due to the important roles of toll-like receptor 4 (TLR4) in cytokine production and inflammation, we aimed to evaluate the effects of TAK-242 (Resatorvid) on interleukin (IL)1-β, IL-6, TNF-α, and TLR4 expression and two important proteins of nuclear factor-κB (NF-κB) signaling pathway (Ikβα and pIkβα) in RA and trauma FLSs. FLSs were isolated from synovial tissues of trauma (n=10) and RA (n=10) patients and cultured in Dulbecco's Modified Eagle Medium (DMEM). 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) was performed to evaluate the cytotoxicity effects of TAK-242 on the RA FLSs. Real-time PCR was performed to measure the expression level of IL1-β, IL-6, TNF-α, and TLR4 genes in Lipopolysaccharide (LPS) and TAK-242 treated FLSs. Furthermore, the treated FLSs were evaluated for protein levels of Ikβα and pIkβα by western blot. The baseline expression of IL1-β, IL-6, TNF-α, and TLR4 showed no significant differences between healthy and RA FLSs. LPS stimulated FLSs significantly increased mRNA levels of IL-1β, IL-6, TNF-α, and TLR4 genes in both the healthy and RA FLSs compared with that of their control groups, and pretreatment with TAK-242 reversed the effect. Furthermore, LPS-stimulated FLSs significantly increased the level of pIkβα in both the healthy and RA FLSs compared with that of their control groups, and pretreatment with TAK-242 reversed the effect. We provide the data that TAK-242 through inhibiting the NF-κB signaling pathway may modulate TLR4-mediated inflammatory responses and could be considered as a potential therapeutic agent for RA patients.


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