Dextran Sulfate Sodium Mouse Research Articles

Abstract 2472: Acute colitis and colitis-associated cancer are exacerbated in mice deficient N-deacetylase/N-sulfotransferase-4

Abstract NDST4 is one member of N-deacetylase/N-sulfotransferase (heparan glucosaminyl) (NDST) family, which are responsible for heparan sulfate (HS) biosynthesis on a core protein to form heparan sulfate proteoglycans (HSPGs). The HS chains of HSPGs bind to and regulate their functions of various growth factors, cytokines and chemokines. HSPGs ubiquitously reside on cell surface, inside the cell, and in the extracellular matrix. Importantly, the content and distribution of HSPGs are altered during tumorigenesis. In the study, 30 (57.7%) of 52 primary colorectal carcinomas showed a dramatic reduction in NDST4 RNA transcripts, and genetic loss of NDST4 was significantly associated with poor survival of patients with colorectal cancer. We further generated an Ndst4-knockout mouse strain, which could develop and reproduce normally. Notably, using the dextran sodium sulfate mouse model of acute colitis, Ndst4 deficiency resulted in a significantly higher disease activity index and obviously hyperemic appearance in the cecum. In the development of colitis-associated cancer, the size of colonic tumors induced by azoxymethane/dextran sodium sulfate was significantly increased in Ndst4-deficient mice compared with wild-type mice. Taken together, loss-of-function of NDST4 might impair the modification of HS chains of specific HSPGs leading to tumor-promoting inflammation in the colon. The full spectrum of signaling pathways contributed by NDST4 to colitis and tumor progression remains to be elucidated. Citation Format: Tzu-Ming Jao, Ming-Hong Tsai, Chi-Yen Huang, Sheng-Tai Tzeng, Jing-Xing Lee, Wei-Chen Lo, Che-Wei Chang, Ya-Chien Yang. Acute colitis and colitis-associated cancer are exacerbated in mice deficient N-deacetylase/N-sulfotransferase-4. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2472. doi:10.1158/1538-7445.AM2014-2472

Anemia and retinal function in a mouse model of acute colitis

Individuals with inflammatory bowel diseases (IBD) have an elevated risk of ocular inflammation. Both the anterior and posterior eye can be affected by IBD, although posterior eye dysfunction is more likely to go undetected. Little investigative attention has been directed toward the mechanisms of ocular dysfunction with IBD; however, given the prevalence of anemia in IBD and the effects of anemia on the retina, we examined the association between retinal function (electroretinography, ERG) and the anemia induced by experimental IBD, and we tested for a potential retinal benefit of acutely attenuating anemia (via red blood cell (RBC) infusion). Colitis was induced in mice in a model involving drinking water ingestion of dextran sodium sulfate (DSS), with untreated drinking water administered to controls. A subset of the DSS mice was infused with RBCs to attenuate the severity of the anemia induced by DSS. ERG signals (a-waves, b-waves, and oscillatory potential amplitudes and implicit times) were compared between the three groups of mice to evaluate retinal function. ERG amplitudes were significantly decreased in DSS mice compared to controls, with the amplitudes demonstrating a positive correlation with hematocrit, that is, the lowest ERG amplitudes were found with the most severe cases of anemia. An acute infusion of RBCs into DSS mice provided an improvement in the oscillatory potential implicit times, but no significant improvements in other ERG parameters. Despite the association between anemia and ERG signals in DSS-induced colitis, acute RBC infusion may only partially attenuate the associated retinal dysfunction.

Preventive effects of cranberry products on experimental colitis induced by dextran sulphate sodium in mice

With the prevalence of inflammatory bowel disease (IBD) and its associated risk for development of colorectal cancer, it is of great importance to prevent and treat IBD. However, due to the complexity of etiology and potentially serious adverse effects, treatment options for IBD are relatively limited. Thus, the purpose of this study was to identify a safe food-based approach for the prevention and treatment of IBD. In this study, we tested the effects of cranberry products on preventing dextran sulphate sodium-induced murine colitis. Our results suggest that both cranberry extract and dried cranberries-fed groups had a significantly reduced disease activity index, where dried cranberries were more effective in preventing colitis than cranberry extract. Shortening of colon length, colonic myeloperoxidase activity and production of pro-inflammatory cytokines were attenuated in animals fed dried cranberries compared to the controls. The current report suggests that cranberries can be applied to prevent and reduce the symptoms of IBD.

Dietary Petitvert supplementation protects against acute colitis induced by dextran sulphate sodium in mice

Dietary Petitvert supplementation protects against acute colitis induced by dextran sulphate sodium in mice

Commensal Gram-positive bacteria initiates colitis by inducing monocyte/macrophage mobilization.

Breakdown of the intestinal epithelial layer's barrier function results in the inflow of commensal flora and improper immune responses against the commensal flora, leading to inflammatory bowel disease (IBD) development. Using a mouse dextran sodium sulfate (DSS)-induced colitis model, we show here that commensal Gram-positive bacteria trigger the mobilization of inflammatory monocytes and macrophages into the colon. Monocytes/macrophages are major producers of tumor necrosis factor-α (TNF-α), a representative cytokine that aggravates colitis. Notably, pretreating mice with vancomycin, which eliminated Gram-positive bacteria, particularly the Lachnospiraceae family, significantly reduced the severity of the colitis by selectively blocking the recruitment of monocytes/macrophages, but not of other cells. Importantly, vancomycin treatment specifically downregulated the colonic epithelial cell (cEC) expression of C-C chemokine receptor type-2 (CCR2) ligands, which are critical chemokines for monocyte/macrophage mobilization into the inflamed colon. Collectively, these results provide previously undiscovered evidence that Gram-positive commensal bacteria induce colitis by recruiting colitogenic monocytes and macrophages. Our findings may lead to new avenues of treatment for IBD.

Mo1765 3D Cell Culture of CaCo2: A Better Model to Study the Functionality and Regulation of Intestinal Ion Transporters

Glucagon-like peptide-1 (GLP-1) is an important gut hormone, which in intestine is secreted by L-cells. In addition to its beneficial roles in insulin secretion, obesity, cardio and neuro protection, recently GLP-1 has also been shown to act as an anti-inflammatory agent. However, its use in clinical practice has been hampered by its short half-life and by the fact that commercially available analogues have increased risk of immunogenicity. It has recently been shown that novel formulation composed of human GLP-1 self-associated to a sterically stabilized phospholipid micelles (SSM), GLP-1 nanomedicine, increased the stability of circulating GLP-1 in the blood, and the nanomedicine had an anti-inflammatory effect against LPS induced inflammation in lungs. Whether GLP-1 nanomedicine exerts anti-inflammatory effects in intestine is not known. We hypothesized that GLP-1 nanomedicine decreases intestinal inflammation and attenuates the associated diarrhea. To test this hypothesis, we used Dextran Sodium Sulfate (DSS) (3% in drinking water for 7 days) induced colitis mouse as a model for intestinal inflammation. Animals were divided into 4 groups (5 mice/group) and i.p. injections of vehicle (SSMs) or GLP-1 (15 nmole/100μl) were given daily: Group 1(Control): vehicle alone; Group 2 (DSS): vehicle+DSS; Group 3 (GLP-1): GLP-1 alone; Group 4 (GLP-1+DSS). Mucosa was scraped from distal colon on day 8 for qRT-PCR and western blotting. Tissue sections were used for immunostaining. DSS mice showed a significant decrease in body weight as compared to control. However, GLP-1 treatment to DSS mice partially attenuated the weight loss. When colons were harvested from experimental mice and examined, loose fecal pellets were observed in the colon of DSS colitis mice reflecting diarrheal phenotype, which was partly alleviated in GLP-1 treated mice. Further, treatment with GLP-1 alleviated the increase in expression of the pro-inflammatory cytokines in colonic epithelium of DSS mice e.g. IL-1β (Control: 2±0.6; DSS: 201±43; GLP-1: 2±0.3 GLP-1+DSS: 78±20); and CXCL-1 (Control: 1±0.3; DSS: 18.9±7; GLP-1: 1.3±0.9; GLP1+DSS: 12±3). Increased levels of pro-inflammatory cytokines have been implicated in the associated diarrhea by decreased expression of chloride transporter SLC26A3 or down regulated in adenoma (DRA). Western blot results showed that DSS decreased the expression of DRA as compared to control but GLP-1 abrogated this effect of DSS (Control: 0.9±0.1; DSS: 0.3±0.1; GLP-1: 1.2±0.1; GLP-1+DSS: 0.6±0.2). This data was further confirmed by immunostaining. Our data showed that GLP-1 nanomedicine is effective in reducing intestinal inflammation and the associated diarrhea. We speculate that GLP-1 nanomedicine could be used as a novel therapeutic approach to treat patients with Crohn's disease and ulcerative colitis. (Supported by NIDDK and Dept. of Veteran Affairs)

Mo1762 A Novel Role of GLP-1 Nanomedicine in Amelioration of Gut Inflammation

Glucagon-like peptide-1 (GLP-1) is an important gut hormone, which in intestine is secreted by L-cells. In addition to its beneficial roles in insulin secretion, obesity, cardio and neuro protection, recently GLP-1 has also been shown to act as an anti-inflammatory agent. However, its use in clinical practice has been hampered by its short half-life and by the fact that commercially available analogues have increased risk of immunogenicity. It has recently been shown that novel formulation composed of human GLP-1 self-associated to a sterically stabilized phospholipid micelles (SSM), GLP-1 nanomedicine, increased the stability of circulating GLP-1 in the blood, and the nanomedicine had an anti-inflammatory effect against LPS induced inflammation in lungs. Whether GLP-1 nanomedicine exerts anti-inflammatory effects in intestine is not known. We hypothesized that GLP-1 nanomedicine decreases intestinal inflammation and attenuates the associated diarrhea. To test this hypothesis, we used Dextran Sodium Sulfate (DSS) (3% in drinking water for 7 days) induced colitis mouse as a model for intestinal inflammation. Animals were divided into 4 groups (5 mice/group) and i.p. injections of vehicle (SSMs) or GLP-1 (15 nmole/100μl) were given daily: Group 1(Control): vehicle alone; Group 2 (DSS): vehicle+DSS; Group 3 (GLP-1): GLP-1 alone; Group 4 (GLP-1+DSS). Mucosa was scraped from distal colon on day 8 for qRT-PCR and western blotting. Tissue sections were used for immunostaining. DSS mice showed a significant decrease in body weight as compared to control. However, GLP-1 treatment to DSS mice partially attenuated the weight loss. When colons were harvested from experimental mice and examined, loose fecal pellets were observed in the colon of DSS colitis mice reflecting diarrheal phenotype, which was partly alleviated in GLP-1 treated mice. Further, treatment with GLP-1 alleviated the increase in expression of the pro-inflammatory cytokines in colonic epithelium of DSS mice e.g. IL-1β (Control: 2±0.6; DSS: 201±43; GLP-1: 2±0.3 GLP-1+DSS: 78±20); and CXCL-1 (Control: 1±0.3; DSS: 18.9±7; GLP-1: 1.3±0.9; GLP1+DSS: 12±3). Increased levels of pro-inflammatory cytokines have been implicated in the associated diarrhea by decreased expression of chloride transporter SLC26A3 or down regulated in adenoma (DRA). Western blot results showed that DSS decreased the expression of DRA as compared to control but GLP-1 abrogated this effect of DSS (Control: 0.9±0.1; DSS: 0.3±0.1; GLP-1: 1.2±0.1; GLP-1+DSS: 0.6±0.2). This data was further confirmed by immunostaining. Our data showed that GLP-1 nanomedicine is effective in reducing intestinal inflammation and the associated diarrhea. We speculate that GLP-1 nanomedicine could be used as a novel therapeutic approach to treat patients with Crohn's disease and ulcerative colitis. (Supported by NIDDK and Dept. of Veteran Affairs)

The precipitation of behavioral defects due to inflammation in the DSS mouse model of colitis (LB748)

Background: Anxiety, depression, and altered memory have been previously associated with intestinal diseases, including inflammatory bowel disease (IBD). Understanding the association between these behavioral changes and IBD may provide clinical significance seeing as concomitant mood disorders often increase a patient’s risk of developing secondary functional gastrointestinal diseases (FGIDs).Aims: The aim of this study was to determine whether active intestinal inflammation precipitates behavioral defects in memory and anxiety and to determine if these changes persist through the resolution of inflammation.Methods: Dextran Sodium Sulfate (DSS) was administered for 5 days via drinking water followed by either 3 days for active inflammation studies or 8 days for resolution of inflammation studies. Mice were weighed daily and colon lengths were measure at the time of sacrifice in order to assess the degree of sickness. Anxiety‐like behavior (light/dark box) and memory (novel object test) were assessed in the DSS mice vs. controls (WT;C57BL/6).Results: DSS mice at the peak of inflammation demonstrated impairments in non‐spatial memory with an exploration ratio of 54.06 +/‐ 1.84 while controls had a mean exploration ratio of 57.91 +/‐ 1.29 (p<.01; n=13). Anxiety‐like behavior was also evident in the DSS mice, which spent 133.91 +/‐10.17 seconds in the light area of the light/dark box while the controls spent 174 +/‐ 14.51 seconds in the light area (p<.04; n=11). These behavioral defects did not persist at the resolution of intestinal inflammation. However, physiological changes, such as a shortening of the colon, were equally evident at the peak of inflammation as well as at the resolution phase.Conclusions: At the peak of inflammation, the DSS mouse model of colitis displays altered baseline behaviors in regards to memory and anxiety. Although physiological changes persist at the resolution of colitis as seen with persistent shortening of the colon, behavioral defects are not evident post inflammation. Taken together, these findings indicate and underlying connection between the brain and the gut relevant to the context of Inflammatory Bowel Disease.

Supplementation of the diet with Salecan attenuates the symptoms of colitis induced by dextran sulphate sodium in mice

As a water-soluble extracellular β-glucan produced by Agrobacterium sp. ZX09, Salecan has an excellent toxicological profile and exerts multiple physiological effects. The aims of the present study were to investigate the protective effects of a Salecan diet in the well-defined dextran sulphate sodium (DSS) model of experimental murine colitis and to elucidate the mechanism involved in its effects with special attention being paid to its effect on the production of TNF-α, a primary mediator involved in the inflammatory response. Male C57BL/6J mice were fed a diet supplemented with either 4 or 8% Salecan for 26d and DSS was administered to induce acute colitis during the last 5d of the experimental period. Several clinical and inflammatory parameters as well as mRNA expression of TNF-α and Dectin-1 were evaluated. The results indicated that the dietary incorporation of Salecan attenuated the severity of DSS colitis as evidenced by the decreased disease activity index, reduced severity of anaemia, attenuated changes in colon architecture and reduced colonic myeloperoxidase activity. This protection was associated with the down-regulation of TNF-α mRNA levels, which might derive from its ability to increase Dectin-1 mRNA levels. In conclusion, the present study suggests that Salecan contributes to the reduction of colonic damage and inflammation in mice with DSS-induced colitis and holds promise as a new, effective nutritional supplement in the management of inflammatory bowel disease.

Local and Systemic Immune Mechanisms Underlying the Anti-Colitis Effects of the Dairy Bacterium Lactobacillus delbrueckii

Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD), showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327), also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS) colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-β, IL-6, and IL-12 in colonic tissue and of TGF-β and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.

Purified PEGylated porcine glucagon-like peptide-2 reduces the severity of colonic injury in a murine model of experimental colitis

The rapid degradation of porcine glucagon-like peptide-2 (pGLP-2) by the enzyme dipeptidyl peptidase-IV (DPP-IV) is the main impediment in the development of pGLP-2 as a potential therapeutic agent for intestinal dysfunction and damage. In this study, one mono-modified Lys30-polyethylene glycol (PEG)-pGLP-2 was prepared using mPEG-succinimidyl propionate. To determine the optimized condition for PEGylation, the reactions were monitored by RP-HPLC and MALDI-TOF-MS. Stability was tested in purified DPP-IV in vitro. In vivo, the protective effects for colonic injury were measured in dextran sulfate sodium (DSS)-induced colitis in mice. The monoPEGylated products reached the maximum yield at 4:1 ratio of mPEG5k-SPA to pGLP-2. An effective method of successfully separating PEGylated pGLP-2 from mPEG-SPA5kD using CM Sepharose Fast Flow resin was established. The half-life of Lys30-PEG-pGLP-2 was 16-fold longer than that of pGLP-2 in DPP-IV. The DSS mice exhibited marked weight loss), which was significantly reduced by Lys30-PEG-pGLP-2 therapy. DSS treatment significantly increased colonic damage score, which was significantly reduced by administration of Lys30-PEG-pGLP-2 in DSS-mice. DSS-induced colitis clearly induced Myeloperoxidase activity in the colon, which was significantly reduced by treatments with 3% DSS-pGLP-2 or 3% DSS-PEG-pGLP-2. These results showed that site-specific Lys30-PEG-GLP-2 was resistant to degradation and reduced the severity of colonic injury in murine colitis. The enhanced biological potency of this product highlighted its potential as a therapeutic agent for intestinal diseases.

Faecalibacterium prausnitzii supernatant improves intestinal barrier function in mice DSS colitis

Objective. The intestinal microbiota plays a substantial role in the pathogenesis of inflammatory bowel disease (IBD). Faecalibacterium prausnitzii (FP) is underrepresented in IBD patients and have been suggested to have anti-inflammatory effects in mice. Increased intestinal permeability is common in IBD but the relationship between FP and intestinal barrier function has not been investigated. Our aim was to study treatment with FP supernatant on intestinal barrier function in a dextran sodium sulfate (DSS) colitis mice model. Material and methods. C57BL/6 mice received 3% DSS in tap water ad libitum during five days to induce colitis. From day 3 the mice received a daily gavage with FP supernatant or broth during seven days. Ileum and colon were mounted in Ussing chambers for permeability studies with 51Cr-EDTA and Escherichia coli K-12. Colon was saved for Western blot analyses of tight junction proteins. Results. DSS-treated mice showed significant weight loss and colon shortening. Gavage with FP supernatant resulted in a quicker recovery after DSS treatment and less extensive colonic shortening. Ileal mucosa of DSS mice showed a significant increase in 51Cr-EDTA-passage compared to controls. 51Cr-EDTA passage was significantly decreased in mice receiving FP supernatant. No significant differences were observed in passage of E. coli K12. Western blots showed a trend to increased claudin-1 and claudin-2 expressions in DSS mice. Conclusions.Supernatant of FP enhances the intestinal barrier function by affecting paracellular permeability, and may thereby attenuate the severity of DSS-induced colitis in mice. These findings suggest a potential role of FP in the treatment of IBD.

New Perspective on Dextran Sodium Sulfate Colitis: Antigen-Specific T Cell Development during Intestinal Inflammation

CD4+ T cell responses against oral antigens can develop in inflammatory bowel disease (IBD) patients, which may modulate disease. Dextran sodium sulfate (DSS) colitis is commonly used to study IBD, however, it is not considered the best model in which to study T cell involvement in intestinal disease. Our aim was to determine if antigen-specific T cells could be induced during DSS colitis and if they could be detected after disease resolution. To induce antigen-specific T cells, the tracking antigen, ovalbumin (OVA), was administered orally during colitis initiation. Disease severity was monitored, and the antigen-reactivity of CD4+ T cells examined using CD69 expression. While OVA-directed, CD4+ Foxp3+ regulatory T cells could be detected in the spleens of both OVA-treated control and DSS mice, OVA-reactive, CD4+ Foxp3-T cells were only found in the OVA and DSS-treated mice. These results indicate that during DSS colitis T cells develop that are specific against oral antigens, and they are found systemically after colitis resolution. This gives added depth and utility to the DSS model as well as a way to track T cells that are primed against luminal antigens.

Supercritical fluid extract from maca alleviates colitis induced by dextran sulfate sodium in mice

The objective of this study was to investigate the possible protective effects of maca (Lepidium meyenii) extract (MLE) by supercritical fluid extraction on dextran sodium sulfate (DSS)-induced colitis. Experimental colitis was induced by giving male BALB/c mice 3% DSS in drinking water, and MLE (30 mg/kg BW), sulfasalazine (100 mg/kg BW) or vehicle were administered orally. DSS challenge caused significant body weight loss, rectal bleeding, diarrhea, shortened colon length, histological changes, and increased myeloperoxidase (MPO) activity in DSS-treated mice. Oral administration of MLE significantly relieved the symptoms of diarrhea and rectal bleeding, and reduced colonic MPO activity (p<0.05). MLE treatment inhibited expression of several colonic proteins related to inflammatory responses, such as interleukin (IL)-1β, tumor necrosis factor-α, IL-6, and S100 calcium-binding protein A8, whose expressions were increased significantly by DSS treatment. These results suggest that MLE can alleviate DSS-induced colitis in mice by modulating colonic inflammatory mediators.

Involvement of autotaxin/lysophospholipase D expression in intestinal vessels in aggravation of intestinal damage through lymphocyte migration

Lysophosphatidic acid (LPA) has a critical role in lymphocyte migration to secondary lymphoid organs. Autotaxin (ATX)/lysophospholipase D, in the vascular endothelium, is the main enzyme involved in LPA production. Whether ATX is involved in pathological lymphocyte migration to the inflamed mucosa has not been studied. We investigated the involvement of ATX in inflammatory bowel disease patients and two murine models of colitis. Tissue samples were obtained by intestinal biopsies from patients with Crohn's disease and those with ulcerative colitis with informed consent. ATX immunoreactivity was colocalized with MAdCAM-1-positive high-endothelial-like vessels, close to sites of lymphocyte infiltration. Enhanced expression of ATX mRNA was observed in the inflamed mucosa from Crohn's disease and ulcerative colitis patients. ATX mRNA expression level was remarkably higher in the actively inflamed mucosa than in the quiescent mucosa in the same patient. In the T-cell-transferred mouse model, ATX mRNA expression level gradually increased as colitis developed. In the dextran sodium sulfate mouse model, the expression level was considerably higher in colonic mucosa of chronically developed colitis than in colonic mucosa of acute colitis. Administration of an ATX inhibitor, bithionol, remarkably decreased lymphocyte migration to the intestine and ameliorated both dextran sodium sulfate-induced colitis and CD4-induced ileocolitis. In transwell assays, administration of bithionol or 1-bromo-3(s)-hydroxy-4-(palmitoyloxy) butylphosphonate (BrP-LPA) significantly decreased transmigration of splenocytes through high-endothelial-like vessels induced by TNF-α. We conclude that enhanced expression of ATX in the active mucosa has been implicated in the pathophysiology of inflammatory bowel disease through enhancing aberrant lymphocyte migration to the inflamed mucosa.

Translational 18F-FDG PET/CT Imaging to Monitor Lesion Activity in Intestinal Inflammation

In patients with inflammatory bowel disease (IBD) and in murine IBD models, mucosal disease activity is routinely assessed by endoscopy and histologic evaluation. This information is valuable for monitoring treatment response, with mucosal healing being a major treatment goal. The aim of this study was to evaluate the translational potential of noninvasive (18)F-FDG PET/CT for the assessment of mucosal damage in murine dextran sodium sulfate (DSS) colitis and human IBD. After induction of DSS colitis, (18)F-FDG uptake was serially assessed from colonic volumes of interest defined on PET/CT scans and intraindividually correlated to histologic findings and to infiltrating cell types. In addition, (18)F-FDG PET/CT scans of 25 Crohn disease patients were analyzed, and colonic (18)F-FDG uptake was correlated to endoscopically assessed damage. At days 4 and 7 after DSS induction, colonic (18)F-FDG uptake was significantly increased, with a distinct peak in the medial colon. (18)F-FDG uptake strongly correlated with histologic epithelial damage. Additionally, (18)F-FDG uptake increased in the bone marrow in the course of the disease, correlating with an increase in intestinal (18)F-FDG uptake. Histology and fluorescence-activated cell sorting analysis of the bone marrow of DSS mice revealed an increased number of immature neutrophils, whereas mucosal polymerase chain reaction suggested a correlation of (18)F-FDG uptake to T cell infiltration. In accordance with the results of (18)F-FDG PET/CT in DSS colitis, an increased (18)F-FDG uptake was found in 87% of deep mucosal ulcerations in IBD patients, whereas mild endoscopic lesions were detected only by (18)F-FDG PET/CT in about 50% of patients assessed. (18)F-FDG PET/CT is a noninvasive method for evaluation of both experimental colitis and Crohn disease patients and thereby offers promising translational potential.

Enterococcus durans EP1 modulates inflammation in a DSS-induced colitis model in mice

Event Abstract Back to Event Enterococcus durans EP1 modulates inflammation in a DSS-induced colitis model in mice Paula Carasi1, 2*, Silvia Racedo2, Claudine Jacquot2, María Serradell1 and María C. Urdaci2 1 Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Dep. de Ciencias Biológicas, Argentina 2 Universite de Bordeaux, Bordeaux Science Agro, France Enterococcus durans EP1, a gram-positive coccoid bacteria, has shown various probiotic properties. The objective of this work was to evaluate the immunomodulatory capacity of EP1 in a colitis model induced by dextran sulfate sodium (DSS) in mice. Six weeks old Swiss mice were separated in two groups of 16 animals. During 14 days, one group received daily 108 cfu/mice of EP1 and the other received PBS. On day 14, each of the mentioned groups was separated in two (eight mice each) and administration of DSS 3% w/v started for one of them and lasted seven days. Significant differences in the disease activity index were observed between DSS group and DSS treated with EP1 mice (DSS-EP1), DSS mice´s colons were shorter (p<0.05) than the colons from control and DSS-EP1 mice. Histological studies were consistent with these findings. Cytokines production by colon explants ex vivo showed that DSS mice secreted higher levels of IL6, IL17A, IFNγ, TNFα and GM-CSF compared with control and DSS-EP1 mice but no differences were observed for IL10. Gene expression studies demonstrated that in colon the expression of IL17A, INFγ, IL1β and CXCL1 was lower in DSS-EP1 group compared with DSS mice. In mLN, expression of IL23, IL17A, RORγT and GM-CSF was significantly decreased in DSS-EP1 group. Moreover, EP1 treatment partially recomposed the changes in the microbiota induced by DSS. These results indicate that administration of E. durans EP1 attenuates damages generated by DSS by decreasing expression and secretion of proinflammatory mediators, as well as modulating microbiota. Keywords: DSS, Probiotics, intestinal inflammation, Enterococcus, microbiota Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Innate immunity Citation: Carasi P, Racedo S, Jacquot C, Serradell M and Urdaci MC (2013). Enterococcus durans EP1 modulates inflammation in a DSS-induced colitis model in mice. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00432 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 29 Mar 2013; Published Online: 22 Aug 2013. * Correspondence: Miss. Paula Carasi, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Dep. de Ciencias Biológicas, La Plata, Argentina, paulacarasi@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Paula Carasi Silvia Racedo Claudine Jacquot María Serradell María C Urdaci Google Paula Carasi Silvia Racedo Claudine Jacquot María Serradell María C Urdaci Google Scholar Paula Carasi Silvia Racedo Claudine Jacquot María Serradell María C Urdaci PubMed Paula Carasi Silvia Racedo Claudine Jacquot María Serradell María C Urdaci Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

TNF-α Inhibitors Attenuate Neuropeptide Y (NPY) Expression in the Murine Enteric Nervous System: Implications in Inflammation and Colonic Motility

Neuropeptide Y (NPY) is a small peptide neurotransmitter produced by the enteric neurons. We have demonstrated that NPY is upregulated in the murine enteric nervous system (ENS) during experimental colitis and that NPY knockout mice are resistant to experimental colitis. However the mechanism of NPY up regulation in the ENS, and its downstream impact on colonic motility are unknown. We investigated whether TNF-α inhibitor, Etanercept, can regulate NPY expression and colonic motility. We utilized an enteric neuronal cell line developed in our laboratory and dextran sodium sulfate mouse model of colitis to study NPY expression as modulated by TNF-α. NPY expression in human colonic biopsies was assessed by real time PCR. Colonic motility was assessed in using isometric muscle recording in isolated circular muscle strips with intact innervation. Neuronal apoptosis was evaluated by cleaved caspase-3 immunostaining. Neuronal nitric oxide synthase containing neurons (nNOS) were quantified by Diaphorase staining. NPY expression was upregulated in human IBD, and IBD colons displayed increased neuronal apoptosis and impaired motility. Etanercept attenuated NPY expression in vitro and in vivo. Etanercept-treated mice exhibited attenuated inflammation and reduction in neuronal apoptosis. There was restoration of nNOS neurons in DSS mice treated with Etanercept, which was evidenced by the reduction in pellet frequency and water content (diarrhea phenotype typical of IBD). Our data establish the significance of NPY-TNF-α interactions in IBD. Motility disorders persist in IBD patients even after the resolution of inflammation; hence it is compelling to further explore the role of TNF-α inhibitors in modulating motility issues associated with inflammatory disorders.

Neutralization of complement component C5 ameliorates the development of dextran sulfate sodium (DSS)-colitis in mice

The complement system is a potent effector of innate immunity. To elucidate the pathophysiological role of the complement system in inflammatory bowel disease, we evaluated the effects of anti-C5 antibodies on the development of dextran sulfate sodium-induced colitis in mice. Dextran sulfate sodium-colitis was induced in BALB/c mice with intraperitoneal administrations of anti-C5 antibodies (1 µg/body) every 48 h. Tissue samples were evaluated by standard histological procedures. The mucosal mRNA expression of the inflammatory cytokines was analyzed by real-time PCR. Body weight loss in the mice was completely blocked by the administration of anti-C5 antibody. The disease activity index was significantly lower in the anti-C5 antibody-treated mice than the dextran sulfate sodium mice. The colonic weight/length ratio, histological colitis score and mucosal myeloperoxidase activity were significantly lower in the anti-C5 antibody-treated mice than the dextran sodium sulfate mice. The administration of the anti-C5 antibody significantly reduced the mucosal expression of mRNAs for tumor necrosis factor-α, interleukin-1β and interleukin-6. In conclusion, the complement system plays a role in the development of dextran sodium sulfate-induced experimental colitis.

Novel Insights on the Effect of Nicotine in a Murine Colitis Model

Studies showed that nicotine has a positive influence on symptoms of ulcerative colitis. In the present study, we explored the effect of nicotine treatment using different routes of administration in the dextran sodium sulfate (DSS) colitis mouse model. We also investigated the effects of cotinine, a major metabolite of nicotine, in the model. C57BL6 adult male mice were given DSS solution freely in the drinking water for seven consecutive days, and tap water was given thereafter. Disease severity, length of the colon, colon tissue histology, and inflammatory markers, including colonic myeloperoxidase activity and colonic tumor necrosis factor-α levels, were evaluated. The effect of nicotine and cotinine treatments via various different routes of administration were examined the DSS model. In addition, we measured the plasma levels of nicotine and cotinine in our treatment protocols. Administration of low, but not high, doses of oral nicotine in DSS-treated mice resulted in a significant decrease in disease severity, histologic damage scores, as well as colonic level of tumor necrosis factor-α. However, the anti-inflammatory effect of nicotine was not seen after chronic s.c. or minipump infusion of the drug. Differences in plasma levels of nicotine and cotinine do not seem to account for this lack of effect. Finally, oral cotinine alone failed to show a significant effect in the DSS model of colitis. These results highlight that dose and route of administration play a critical role in the protective effect of nicotine in the DSS mouse colitis model.