scholarly journals Prevention of Adult Colitis by Oral Ferric Iron in Juvenile Mice Is Associated with the Inhibition of the Tbet Promoter Hypomethylation and Gene Overexpression

Nutrients ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1758 ◽  
Author(s):  
Chourouk Ettreiki ◽  
Abalo Chango ◽  
Nicolas Barbezier ◽  
Moise Coeffier ◽  
Pauline M Anton ◽  
...  

Iron is an essential nutrient needed for physiological functions, particularly during the developmental period of the early childhood of at-risk populations. The purpose of this study was to investigate, in an experimental colitis, the consequences of daily oral iron ingestion in the early period on the inflammatory response, the spleen T helper (Th) profiles and the associated molecular mechanisms. Juvenile mice orally received microencapsulated ferric iron or water for 6 weeks. On adult mice, we induced a sham or experimental trinitrobenzene sulfonic acid (TNBS) moderate colitis during the last week of the experiment before sacrificing the animals 7 days later. The severity of the gut inflammation was assessed by macroscopic damage scores (MDS) and the myeloperoxidase activity (MPO). Th profiles were evaluated by the examination of the splenic gene expression of key transcription factors of the Th differentiation (Tbet, Gata3, Foxp3 and RORγ) and the methylation of their respective promoter. While TNBS-induced colitis was associated with a change of the Th profile (notably an increase in the Tbet/Gata3 ratio in the spleen), the colitis-inhibition induced by ferric iron was associated with a limitation of the splenic Th profiles perturbation. The inhibition of the splenic Tbet gene overexpression was associated with an inhibition of promoter hypomethylation. In summary, mice treated by long-term oral ferric iron in the early period of life exhibited an inhibition of colitis associated with the inhibition of the splenic Tbet promoter hypomethylation and gene overexpression.

2000 ◽  
Vol 279 (1) ◽  
pp. G238-G244 ◽  
Author(s):  
Maureen N. Ajuebor ◽  
Anita Singh ◽  
John L. Wallace

The ability of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors to exacerbate inflammatory bowel disease suggests that prostaglandins are important anti-inflammatory mediators in this context. Prostaglandin D2 has been suggested to exert anti-inflammatory effects. We investigated the possibility that prostaglandin D2 derived from cyclooxygenase-2 plays an important role in downregulating colonic inflammation in rats. Colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid. At various times thereafter (from 1 h to 7 days), colonic prostaglandin synthesis and myeloperoxidase activity (index of granulocyte infiltration) were measured. Prostaglandin D2synthesis was elevated >4-fold above controls within 1–3 h of induction of colitis, preceding significant granulocyte infiltration. Treatment with a selective cyclooxygenase-2 inhibitor abolished the increase in prostaglandin D2 synthesis and caused a doubling of granulocyte infiltration. Colonic granulocyte infiltration was significantly reduced by administration of prostaglandin D2 or a DP receptor agonist (BW-245C). These results demonstrate that induction of colitis results in a rapid increase in prostaglandin D2 synthesis via cyclooxygenase-2. Prostaglandin D2 downregulates granulocyte infiltration into the colonic mucosa, probably through the DP receptor.


Author(s):  
Yong Fu ◽  
Gailing Ma ◽  
Yuqian Zhang ◽  
Wenli Wang ◽  
Tongguo Shi ◽  
...  

Abstract Background Interleukin-10 (IL-10) is a potent immunoregulatory cytokine that plays a pivotal role in maintaining mucosal immune homeostasis. As a novel synthetic inhibitor of salt-inducible kinases (SIKs), HG-9-91-01 can effectively enhance IL-10 secretion at the cellular level, but its in vivo immunoregulatory effects remain unclear. In this study, we investigated the effects and underlying mechanism of HG-9-91-01 in murine colitis models. Methods The anti-inflammatory effects of HG-9-91-01 were evaluated on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-, dextran sulfate sodium–induced colitis mice, and IL-10 knockout chronic colitis mice. The in vivo effector cell of HG-9-91-01 was identified by fluorescence-activated cell sorting and quantitative real-time polymerase chain reaction. The underlying mechanism of HG-9-91-01 was investigated via overexpressing SIKs in ANA-1 macrophages and TNBS colitis mice. Results Treatment with HG-9-91-01 showed favorable anticolitis effects in both TNBS- and DSS-treated mice through significantly promoting IL-10 expression in colonic macrophages but failed to protect against IL-10 KO murine colitis. Further study indicated that HG-9-91-01 markedly enhanced the nuclear level of cAMP response element-binding protein (CREB)-regulated transcription coactivator 3 (CRTC3), whereas treatment with lentiviruses encoding SIK protein markedly decreased the nuclear CRTC3 level in HG-9-91-01–treated ANA-1 macrophages. In addition, intracolonic administration with lentiviruses encoding SIK protein significantly decreased the nuclear CRTC3 level in the lamina propria mononuclear cells and ended the anti-inflammatory activities of HG-9-91-01. Conclusions We found that HG-9-91-01 promoted the IL-10 expression of colonic macrophages and exhibited its anticolitis activity through the SIK/CRTC3 axis, and thus it may represent a promising strategy for inflammatory bowel disease therapy.


2021 ◽  
Vol 11 ◽  
Author(s):  
Réka Á. Kovács ◽  
Henrietta Vadászi ◽  
Éva Bulyáki ◽  
György Török ◽  
Vilmos Tóth ◽  
...  

Elements of the immune system particularly that of innate immunity, play important roles beyond their traditional tasks in host defense, including manifold roles in the nervous system. Complement-mediated synaptic pruning is essential in the developing and healthy functioning brain and becomes aberrant in neurodegenerative disorders. C1q, component of the classical complement pathway, plays a central role in tagging synapses for elimination; however, the underlying molecular mechanisms and interaction partners are mostly unknown. Neuronal pentraxins (NPs) are involved in synapse formation and plasticity, moreover, NP1 contributes to cell death and neurodegeneration under adverse conditions. Here, we investigated the potential interaction between C1q and NPs, and its role in microglial phagocytosis of synapses in adult mice. We verified in vitro that NPs interact with C1q, as well as activate the complement system. Flow cytometry, immunostaining and co-immunoprecipitation showed that synapse-bound C1q colocalizes and interacts with NPs. High-resolution confocal microscopy revealed that microglia-surrounded C1q-tagged synapses are NP1 positive. We have also observed the synaptic occurrence of C4 suggesting that activation of the classical pathway cannot be ruled out in synaptic plasticity in healthy adult animals. In summary, our results indicate that NPs play a regulatory role in the synaptic function of C1q. Whether this role can be intensified upon pathological conditions, such as in Alzheimer’s disease, is to be disclosed.


1997 ◽  
Vol 273 (2) ◽  
pp. R623-R629 ◽  
Author(s):  
N. Vergnolle ◽  
C. Comera ◽  
J. More ◽  
M. Alvinerie ◽  
L. Bueno

Lipocortin 1 is considered a mediator of the anti-inflammatory actions of glucocorticoids. We have shown that this protein is overexpressed and secreted during an experimental colitis induced by intraluminal injection of trinitrobenzenesulfonic acid (TNBS) in rats. We studied here the in vivo regulation of lipocortin 1 expression and secretion in this model, either by glucocorticoids using adrenalectomized or dexamethasone-treated (3 mg/24 h) animals or by pituitary factors using hypophysectomized animals. Inflammation was evaluated by measuring myeloperoxidase activity and by histological scoring of the damage. Lipocortin 1 was detected by immunoblotting, and its secretion was studied by incubating colonic specimens in-culture medium. In the colon of TNBS-injected animals, cumulative histological damage scores were increased in adrenalectomized and decreased in dexamethasone-treated animals compared with control and hypophysectomized animals. The colons of all TNBS-injected animals (controls, adrenalectomized, dexamethasone treated, hypophysectomized) overexpressed and secreted lipocortin 1. In conclusion, the induction of lipocortin 1 overexpression and secretion during this colitis occurs independently of glucocorticoids or pituitary factors.


2000 ◽  
Vol 192 (1) ◽  
pp. 41-52 ◽  
Author(s):  
Atsushi Kitani ◽  
Ivan J. Fuss ◽  
Kazuhiko Nakamura ◽  
Owen M. Schwartz ◽  
Takashi Usui ◽  
...  

In this study, we show that a single intranasal dose of a plasmid encoding active transforming growth factor β1 (pCMV-TGF-β1) prevents the development of T helper cell type 1 (Th1)-mediated experimental colitis induced by the haptenating reagent, 2,4,6-trinitrobenzene sulfonic acid (TNBS). In addition, such plasmid administration abrogates TNBS colitis after it has been established, whereas, in contrast, intraperitoneal administration of rTGF-β1 protein does not have this effect. Intranasal pCMV-TGF-β1 administration leads to the expression of TGF-β1 mRNA in the intestinal lamina propria and spleen for 2 wk, as well as the appearance of TGF-β1–producing T cells and macrophages in these tissues, and is not associated with the appearances of fibrosis. These cells cause marked suppression of interleukin (IL)-12 and interferon (IFN)-γ production and enhancement of IL-10 production; in addition, they inhibit IL-12 receptor β2 (IL-12Rβ2) chain expression. Coadministration of anti–IL-10 at the time of pCMV-TGF-β1 administration prevents the enhancement of IL-10 production and reverses the suppression of IL-12 but not IFN-γ secretion. However, anti–IL-10 leads to increased tumor necrosis factor α production, especially in established colitis. Taken together, these studies show that TGF-β1 inhibition of a Th1-mediated colitis is due to: (a) suppression of IL-12 secretion by IL-10 induction and (b) inhibition of IL-12 signaling via downregulation of IL-12Rβ2 chain expression. In addition, TGF-β1 may also have an inhibitory effect on IFN-γ transcription.


2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Isabel Andújar ◽  
José Luis Ríos ◽  
Rosa María Giner ◽  
José Miguel Cerdá ◽  
María del Carmen Recio

The naphthoquinone shikonin, a major component of the root ofLithospermum erythrorhizon, now is studied as an anti-inflammatory agent in the treatment of ulcerative colitis (UC). Acute UC was induced in Balb/C mice by oral administration of 5% dextran sodium sulfate (DSS). The disease activity index was evaluated, and a histologic study was carried out. Orally administered shikonin reduces induced UC in a dose-dependent manner, preventing the shortening of the colorectum and decreasing weight loss by 5% while improving the appearance of feces and preventing bloody stools. The disease activity index score was much lower in shikonin-treated mice than in the colitic group, as well as the myeloperoxidase activity. The expression of cyclooxygenase-2 was reduced by 75%, activation of NF-κB was reduced by 44%, and that of pSTAT-3 by 47%, as well as TNF-α, IL-1β, and IL-6 production. Similar results were obtained in primary macrophages culture. This is the first report of shikonin’s ability to attenuate acute UC induced by DSS. Shikonin acts by blocking the activation of two major targets: NF-κB and STAT-3, and thus constitutes a promising potential therapeutic agent for the management of the inflammatory bowel disease.


Gut ◽  
1999 ◽  
Vol 45 (2) ◽  
pp. 199-209 ◽  
Author(s):  
B Zingarelli ◽  
C Szabó ◽  
A L Salzman

BACKGROUNDOxidative and nitrosative stress have been implicated in the pathogenesis of inflammatory bowel diseases.AIMSTo study the role of nitric oxide (NO) derived from inducible NO synthase (iNOS) in an experimental model of murine enterocolitis.METHODSTrinitrobenzene sulphonic acid (TNBS) was instilled per rectum to induce a lethal colitis in iNOS deficient mice and in wild type controls. The distal colon was evaluated for histological evidence of inflammation, iNOS expression and activity, tyrosine nitration and malondialdehyde formation (as indexes of nitrosative and oxidative stress), myeloperoxidase activity (as index of neutrophil infiltration), and tissue localisation of intercellular adhesion molecule 1 (ICAM-1).RESULTSTNBS administration induced a high mortality and weight loss associated with a severe colonic mucosal erosion and ulceration, increased myeloperoxidase activity, increased concentrations of malondialdehyde, and an intense staining for nitrotyrosine and ICAM-1 in wild type mice. Genetic ablation of iNOS gene conferred to mice a significant resistance to TNBS induced lethality and colonic damage, and notably reduced nitrotyrosine formation and concentrations of malondialdehyde; it did not, however, affect neutrophil infiltration and intestinal ICAM-1 expression in the injured tissue.CONCLUSIONData show that activation of iNOS is required for nitrosative and oxidative damage in experimental colitis.


2017 ◽  
Vol 114 (17) ◽  
pp. 4513-4518 ◽  
Author(s):  
Verónica Bobo-Jiménez ◽  
María Delgado-Esteban ◽  
Julie Angibaud ◽  
Irene Sánchez-Morán ◽  
Antonio de la Fuente ◽  
...  

Disruption of neuronal morphology contributes to the pathology of neurodegenerative disorders such as Alzheimer’s disease (AD). However, the underlying molecular mechanisms are unknown. Here, we show that postnatal deletion of Cdh1, a cofactor of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase in neurons [Cdh1 conditional knockout (cKO)], disrupts dendrite arborization and causes dendritic spine and synapse loss in the cortex and hippocampus, concomitant with memory impairment and neurodegeneration, in adult mice. We found that the dendrite destabilizer Rho protein kinase 2 (Rock2), which accumulates in the brain of AD patients, is an APC/CCdh1 substrate in vivo and that Rock2 protein and activity increased in the cortex and hippocampus of Cdh1 cKO mice. In these animals, inhibition of Rock activity, using the clinically approved drug fasudil, prevented dendritic network disorganization, memory loss, and neurodegeneration. Thus, APC/CCdh1-mediated degradation of Rock2 maintains the dendritic network, memory formation, and neuronal survival, suggesting that pharmacological inhibition of aberrantly accumulated Rock2 may be a suitable therapeutic strategy against neurodegeneration.


2010 ◽  
Vol 299 (6) ◽  
pp. G1298-G1307 ◽  
Author(s):  
Laurent Ferrier ◽  
Claudine Serradeil-Le Gal ◽  
Anke M. Schulte ◽  
Valentina Vasina ◽  
Eric Gaultier ◽  
...  

Vasopressin and its receptors modulate several gut functions, but their role in intestinal inflammation is unknown. Our aims were to determine 1) the localization of V1b receptors in human and rodent colon, 2) the role of vasopressin and V1b receptors in experimental colitis using two approaches: V1b−/− mice and a selective V1b receptor antagonist, SSR149415, and 3) the mechanisms involved. V1b receptors were localized in normal and inflamed colon from humans and rats. Experimental colitis was induced in rats and mice and some groups were treated before or after colitis induction with oral SSR149415 (3–30 mg/kg). Other groups of mice were submitted to dehydration to increase vasopressin plasma levels, prior to colitis induction. Body weight, damage scores, MPO, and TNF-α tissue levels were determined. Finally, colonic segments of wild-type (WT) and V1b−/− mice were mounted in Ussing chambers and paracellular permeability in response to vasopressin was studied. V1b receptors were expressed in enterocytes and ganglia cells of the enteric nervous system of human and rat intestine. Expression levels were independent from inflammatory status. Colitis was less severe in rodents treated by either preventive or curative SSR149415 and in V1b−/− mice. 2,4,6-Trinitrobenzene sulfonic acid induced a strong mortality in dehydrated animals that was reversed by preventive SSR149415 or mast cell stabilizer. Vasopressin significantly increased paracellular permeability in WT, but not in V1b−/− mice. Preincubation of colon tissues with SSR149415 abolished the vasopressin effect. Similarly, vasopressin had no effect in colonic preparations from WT mice pretreated with mast cell stabilizers. Vasopressin, through V1b receptor interaction, has proinflammatory properties linked to mast cell activation and downstream alterations of the colonic epithelial barrier. These findings underline the potential interest of V1b receptor blockers in gut inflammatory diseases.


2017 ◽  
Vol 8 (3) ◽  
pp. 407-419 ◽  
Author(s):  
S.-M. Lim ◽  
H.M. Jang ◽  
S.-E. Jang ◽  
M.J. Han ◽  
D.-H. Kim

In the present study, we isolated Lactobacillus fermentum IM12 from human gut microbiota, which strongly inhibited interleukin (IL)-6 expression and STAT3 activation in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages, and examined its anti-inflammatory effect in mice with carrageenan-induced hind-paw oedema (CIE) or 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis (TIC). Oral administration of IM12 (0.2×109, 1×109 or 5×109 cfu/mouse, once a day for 3 days) in mice with CIE significantly suppressed the increase of oedema volume and thickness, as well as myeloperoxidase activity and IL-6, IL-17, NO, and prostaglandin E2 levels in the carrageenan-stimulated paw. Treatment with IM12 (1×109 cfu/mouse, once a day for 3 days) in mice with TIC significantly suppressed colon shortening, and myeloperoxidase activity and IL-6 and IL-17 levels. Treatment with IM12 in mice with CIE or TIC also suppressed the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, as well as activation of nuclear factor kappa beta (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Furthermore, IM12 significantly inhibited the expression of iNOS, and COX-2, as well as activation of NF-κB in LPS-stimulated mouse peritoneal macrophages. The inflammatory effect of heat-inactivated IM12 was significantly different to that of live IM12 in mice with TIC, although anti-inflammatory effect of IM12 was reduced by heat treatment. Based on these findings, IM12 may attenuate inflammation by inhibiting NF-κB-STAT3 signalling pathway.


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