Dextran Sulfate Sodium Model Research Articles

A new therapeutic association to manage relapsing experimental colitis: Doxycycline plus Saccharomyces boulardii

Immunomodulatory antibiotics have been proposed for the treatment of multifactorial conditions such as inflammatory bowel disease. Probiotics are able to attenuate intestinal inflammation, being considered as safe when chronically administered. The aim of the study was to evaluate the anti-inflammatory effects of doxycycline, a tetracycline with immunomodulatory properties, alone and in association with the probiotic Saccharomyces boulardii CNCMI-745. Doxycycline was assayed both in vitro (Caco-2 epithelial cells and RAW 264.7 macrophages) and in vivo, in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis and the dextran sodium sulfate (DSS) model of mouse colitis. In addition, the anti-inflammatory effect of the association of doxycycline and the probiotic was evaluated in vitro and in vivo in a DSS model of reactivated colitis in mice. Doxycycline displayed immunomodulatory activity in vitro, reducing IL-8 production by intestinal epithelial cells and nitric oxide by macrophages. Doxycycline administration to TNBS-colitic rats (5, 10 and 25mg/kg) ameliorated the intestinal inflammatory process, being its efficacy comparable to that previously showed by minocycline. Doxycycline treatment was also effective in reducing acute intestinal inflammation in the DSS model of mouse colitis. The association of doxycycline and S. boulardii helped managing colitis in a reactivated model of colitis, by reducing intestinal inflammation and accelerating the recovery and attenuating the relapse. This was evidenced by a reduced disease activity index, colonic tissue damage and expression of inflammatory mediators. This study confirms the intestinal anti-inflammatory activity of doxycycline and supports the potential use of its therapeutic association with S. boulardii for the treatment of inflammatory bowel diseases, in which doxycycline is used to induce remission and long term probiotic administration helps to prevent the relapses.

Impact of colonic mucosal lipoxin A4 synthesis capacity on healing in rats with dextran sodium sulfate-induced colitis

Ulcerative colitis is a chronic inflammatory disease of the colon. This study evaluates the role of colonic mucosal lipoxin A4 (LXA4) synthesis in an experimental rat model of dextran sodium sulfate (DSS)-induced colitis. Wistar rats were randomly assigned to four groups: healthy controls, DSS-induced colitis with no or vehicle therapy, misoprostol or 5-aminosalicylic acid (5-ASA) therapy groups. Disease severity and colonic mucosal LXA4 synthesis was assessed specifically during the acute phase (day 5), chronic phase (day 15) and healing phases (day 19).Both misoprostol and 5-ASA reduced histopathologic score during the acute phase and reduced disease activity score at the healing phase. In addition, misoprostol reduced histopathologic score and colon weight/length ratio during the healing phase. Only misoprostol therapy increased colonic mucosal LXA4 synthesis. Furthermore, LXA4 levels correlated negatively with disease progression (R=−0.953). Collectively, our findings suggest that misoprostol-induced LXA4 synthesis may be favorable for the healing of ulcerative colitis.

Mo1714 Analysis of the Protease MT1-MMP As Therapeutic Target in IBD

Background: We have recently demonstrate higher levels of the MT1-MMP by qPCR -in biopsiesand higher levels of its substrates thrombospondin-1 (TSP1) and nidogen-1 (NID1) -in serumfrom patients of inflammatory bowel disease (IBD), a chronic disorder involving inflammation and angiogenesis. Our objective was analysing the functional role of MT1MMP in the angiogenesis and damage produced in IBD. Methods: Gene expression of MT1MMP was detected by qPCR in biopsies, and TNFα, VEGFA, TSP1, NID1 levels were quantified by ELISA in serum from patients with active ulcerative colitis (UC) or Crohn's disease (CD). Clinical IBD activity was assessed respectively by the Mayo score for UC, and by the Harvey-Bradshaw index for CD. Endoscopic activity was determined with the Mayo subscore and the SES-CD index. MT1-MMP, TSP1 and NID1 expression and the angiogenic response were also analyzed by immunostaining (IF) in colonic sections from controls or patients affected by IBD. Besides, we used a mouse model of dextran sulphate sodium (DSS)induced colitis to analysed the angiogenic response by IF with the specific endothelial cell markers CD31, VE cadherin, and the expression of MT1-MMP, and its substrates TSP1 and NID1 by IF of histological colon sections from either control mice or mice treated with 1% DSS (moderate colitis) or 4% DSS (severe colitis), in wild type mice. The endothelial MT1MMP expression was also analysed in MT1-MMPLacZ/+ mice. Finally, the in vivo functional analysis was done in mice with endothelium-specific deletion of MT1-MMP generated by (MT1-MMPflox/floxxVECadhERT2-Cre) breeding analyzing: (i) colitis score; (ii) vascular pattern quantifying, perfusion, endothelial proliferation and colonic hypoxia (injection and stainings of isolectinB4, EdU, and Pimonidazole); and (iii) inflammatory infiltrate (IF with CD11b). Results: MT1-MMP expression was higher in biopsies of patients with active IBD, moreover, serum levels of TSP-1 and NID1 were significantly increased in UC and CD patients with low activity. In the mouse colitis model, serum levels of TNFα, VEGF-A, TSP1 y NID1 and MT1-MMP expression in intestinal tissues, were increased along the progression of the mouse disease, as well as the angiogenesis in the intestinal mucosa. Our preliminary results indicate that the absence of MT1-MMP in EC protects from IBD, through a vascular normalization (reestablishment of structure and function of blood vessels), with the consequent decrease of colonic hypoxia and inflammation. Conclusions: These data support the potential use of TSP1 and NID1 as biomarkers in the diagnostic of pre-symptomatic or low activity IBD, aiming the endothelial MT1-MMP as a new therapeutic target for normalization of vasculature and improve the symptoms in IBD.

Mo1715 The Effect of Lymphocyte Function Associated Antigen-1 on Inflammatory Bowel Disease by Regulating Treg Cells

Background: We have recently demonstrate higher levels of the MT1-MMP by qPCR -in biopsiesand higher levels of its substrates thrombospondin-1 (TSP1) and nidogen-1 (NID1) -in serumfrom patients of inflammatory bowel disease (IBD), a chronic disorder involving inflammation and angiogenesis. Our objective was analysing the functional role of MT1MMP in the angiogenesis and damage produced in IBD. Methods: Gene expression of MT1MMP was detected by qPCR in biopsies, and TNFα, VEGFA, TSP1, NID1 levels were quantified by ELISA in serum from patients with active ulcerative colitis (UC) or Crohn's disease (CD). Clinical IBD activity was assessed respectively by the Mayo score for UC, and by the Harvey-Bradshaw index for CD. Endoscopic activity was determined with the Mayo subscore and the SES-CD index. MT1-MMP, TSP1 and NID1 expression and the angiogenic response were also analyzed by immunostaining (IF) in colonic sections from controls or patients affected by IBD. Besides, we used a mouse model of dextran sulphate sodium (DSS)induced colitis to analysed the angiogenic response by IF with the specific endothelial cell markers CD31, VE cadherin, and the expression of MT1-MMP, and its substrates TSP1 and NID1 by IF of histological colon sections from either control mice or mice treated with 1% DSS (moderate colitis) or 4% DSS (severe colitis), in wild type mice. The endothelial MT1MMP expression was also analysed in MT1-MMPLacZ/+ mice. Finally, the in vivo functional analysis was done in mice with endothelium-specific deletion of MT1-MMP generated by (MT1-MMPflox/floxxVECadhERT2-Cre) breeding analyzing: (i) colitis score; (ii) vascular pattern quantifying, perfusion, endothelial proliferation and colonic hypoxia (injection and stainings of isolectinB4, EdU, and Pimonidazole); and (iii) inflammatory infiltrate (IF with CD11b). Results: MT1-MMP expression was higher in biopsies of patients with active IBD, moreover, serum levels of TSP-1 and NID1 were significantly increased in UC and CD patients with low activity. In the mouse colitis model, serum levels of TNFα, VEGF-A, TSP1 y NID1 and MT1-MMP expression in intestinal tissues, were increased along the progression of the mouse disease, as well as the angiogenesis in the intestinal mucosa. Our preliminary results indicate that the absence of MT1-MMP in EC protects from IBD, through a vascular normalization (reestablishment of structure and function of blood vessels), with the consequent decrease of colonic hypoxia and inflammation. Conclusions: These data support the potential use of TSP1 and NID1 as biomarkers in the diagnostic of pre-symptomatic or low activity IBD, aiming the endothelial MT1-MMP as a new therapeutic target for normalization of vasculature and improve the symptoms in IBD.

Apoptotic cells induce NF-κB and inflammasome negative signaling.

As they undergo phagocytosis, most early apoptotic cells negatively regulate proinflammatory signaling and were suggested as a major mechanism in the resolution of inflammation. The dextran sulfate sodium model is generally viewed as an epithelial damage model suited to investigate innate immune responses. Macrophages primed with LPS and subsequently exposed to DSS secrete high levels of IL-1β in an NLRP3-, ASC-, and caspase-1-dependent manner. The aim of this research was to test the therapeutic effect of a single dose of apoptotic cells in a DSS-colitis model and to explore possible mechanisms. Primary peritoneal macrophages, the DSS mice model, and Nlrp3-deficient mice, were used to assess the effect apoptotic cells on colitis. Immunohistochemistry, flow-cytometer, and western blots helped to explore the effect and mechanisms. Using a variety of NLRP3 triggering mechanisms, we show that apoptotic cells negatively regulate NF-κB and NLRP3 activation in primary peritoneal macrophages, at pre- and post-transcription levels, via inhibition of reactive oxygen species, lysosomal stabilization, and blocking K+ efflux. This property of apoptotic cells is demonstrated in a dramatic clinical, histological, and immunological amelioration of DSS colitis in Balb/c and B6 mice following a single administration of apoptotic cells.

KAG-308, a newly-identified EP4-selective agonist shows efficacy for treating ulcerative colitis and can bring about lower risk of colorectal carcinogenesis by oral administration

Agonists for EP4 receptor, a prostaglandin E2 receptor subtype, appear to be a promising therapeutic strategy for ulcerative colitis (UC) due to their anti-inflammatory and epithelial regeneration activities. However, the clinical development of orally-available EP4 agonists for mild to moderate UC has not yet been reported. Furthermore, the possibility of an increased risk of colitis-associated cancer (CAC) through direct proliferative effects on epithelial cells via EP4 signaling has not been ruled out. Recently, we identified KAG-308 as an orally-available EP4-selective agonist. Here, we investigated the pharmacological and pharmacokinetic profiles of KAG-308. Then, we compared KAG-308 and sulfasalazine (SASP) for their abilities to prevent colitis and promote mucosal healing in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Finally, the effect of KAG-308 treatment on CAC was evaluated in an azoxymethane (AOM)/DSS-induced CAC mouse model. KAG-308 selectively activated EP4 and potently inhibited tumor necrosis factor-α production in peripheral whole blood and T cells. Oral administration of KAG-308, which showed relatively high bioavailability, suppressed the onset of DSS-induced colitis and promoted histological mucosal healing, while SASP did not. KAG-308 also prevented colorectal carcinogenesis by inhibiting colitis development and consequently decreasing mortality in a CAC model, whereas SASP had marginal effects. In contrast, MF-482, an EP4 antagonist, increased mortality. These results indicated that orally-administered KAG-308 suppressed colitis development and promoted mucosal healing. Moreover, it exhibited preventive effects on colorectal carcinogenesis, and thus may be a new therapeutic strategy for the management of UC that confers a reduced risk of colorectal carcinogenesis.

Polyphosphate, an active molecule derived from probiotic Lactobacillus brevis, improves the fibrosis in murine colitis

Inflammatory bowel disease frequently causes intestinal obstruction because of extensive fibrosis. This study investigated whether polyphosphate (poly P), an active molecule derived from Lactobacillus brevis, could improve the fibrosis in a model of chronic colitis. In this study, dextran sodium sulfate (DSS)-induced chronic colitis models and trinitrobenzene sulfonic acid (TNBS)-induced colitis models were used as models of fibrosis. To clarify the mechanism responsible for the observed effects, Caco-2/brush border epithelial (BBE) and naive T helper lymphocyte (THP)-1 cells were treated with lipopolysaccharide (LPS) to induce inflammation. Non-cancer human colon fibroblast (CCD-18) cells were treated with transforming growth factor beta 1 (TGF-β1) to induce fibrosis. The expression levels of fibrosis- and inflammation-associated molecules were evaluated by both a Western blotting analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). The histologic inflammation and fibrosis were significantly improved in the group administered poly P in both the DSS and TNBS colitis models. The levels of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) were significantly decreased by poly P treatment. The expression levels of TGF-β1 and collagens in the colitis mice were decreased by poly P. The LPS-induced expressions of IL-1β and TGF-β1 in Caco-2/BBE cells and of TNF-α in THP-1 cells were reduced by poly P treatment. Poly P did not affect the expression of collagens and connective tissue growth factor in the CCD-18 cells. In conclusion, poly P suppresses intestinal inflammation and fibrosis by downregulating the expression of inflammation- and fibrosis-associated molecules in the intestinal epithelium. The administration of poly P is therefore a novel option to treat fibrosis because of chronic intestinal inflammation.

Oral administration of hen egg white ovotransferrin attenuates the development of colitis induced by dextran sodium sulfate in mice.

Ovotransferrin (OVT), one of the major hen egg white proteins, was shown to possess antimicrobial and antioxidant activities in vitro. However, there is no information regarding the in vivo preventative effect in chronic inflammatory diseases such as inflammatory bowel disease (IBD). The aim of the present study is to evaluate the anti-inflammatory effects of OVT in a mouse model of dextran sodium sulfate (DSS)-induced colitis. OVT (50 or 250 mg/kg BW) was given orally for 14 days to female BALB/c mice, and 5% DSS (MW 36-50 kDa) was used to induce acute colitis (days 7-14) via drinking water. The current in vivo study demonstrated that OVT significantly reduced clinical signs, weight loss, shortening of the colon, and inflammatory cytokine markers of disease. The histopathological analysis of the colon revealed that OVT reduced histological scores. These results indicate that the use of OVT may be a potential promising candidate for the prevention of IBD.

Pharmacological activity of 6-gingerol in dextran sulphate sodium-induced ulcerative colitis in BALB/c mice.

Gingerols are phenolic compounds in ginger (Zingiber officinale), which have been reported to exhibit antiinflammatory, antioxidant, and anticancer properties. The present study aimed at evaluating the possible pharmacologic activity of 6-gingerol in a mouse model of dextran sulphate sodium (DSS)-induced ulcerative colitis. Adult male mice were exposed to DSS in drinking water alone or co-treated with 6-gingerol orally at 50, 100, and 200 mg/kg for 7 days. Disease activity index, inflammatory mediators, oxidative stress indices, and histopathological examination of the colons were evaluated to monitor treatment-related effects of 6-gingerol in DSS-treated mice. Administration of 6-gingerol significantly reversed the DSS-mediated reduction in body weight, diarrhea, rectal bleeding, and colon shrinkage to near normal. Moreover, 6-gingerol significantly suppressed the circulating concentrations of interleukin-1β and tumor necrosis factor alpha and restored the colonic nitric oxide concentration and myeloperoxidase activity to normal in DSS-treated mice. 6-Gingerol efficiently prevented colonic oxidative damage by increasing the activities of antioxidant enzymes and glutathione content, decreasing the hydrogen peroxide and malondialdehyde levels, and ameliorated the colonic atrophy in DSS-treated mice. 6-Gingerol suppressed the induction of ulcerative colitis in mice via antioxidant and antiinflammatory activities, and may thus represent a potential anticolitis drug candidate.

γ-Glutamyl cysteine and γ-glutamyl valine inhibit TNF-α signaling in intestinal epithelial cells and reduce inflammation in a mouse model of colitis via allosteric activation of the calcium-sensing receptor

BackgroundThe extracellular calcium-sensing receptor (CaSR) is distributed throughout the gastrointestinal tract, and its activation has been shown to promote intestinal homeostasis, suggesting that CaSR may be a promising target for novel therapies to prevent chronic intestinal inflammation such as inflammatory bowel disease (IBD). The γ-glutamyl dipeptides γ-glutamyl cysteine (γ-EC) and γ-glutamyl valine (γ-EV) are dietary flavor enhancing compounds, and have been shown to activate CaSR via allosteric ligand binding. The aim of this study was to examine the anti-inflammatory effects of γ-EC and γ-EV in vitro in intestinal epithelial cells and in a mouse model of intestinal inflammation. ResultsIn vitro, treatment of Caco-2 cells with γ-EC and γ-EV resulted in the CaSR-mediated reduction of TNF-α-stimulated pro-inflammatory cytokines and chemokines including IL-8, IL-6, and IL-1β, and inhibited phosphorylation of JNK and IκBα, while increasing expression of IL-10. In vivo, using a mouse model of dextran sodium sulfate (DSS)-induced colitis, γ-EC and γ-EV treatment ameliorated DSS-induced clinical signs, weight loss, colon shortening and histological damage. Moreover, γ-EC and γ-EV reduced the expression of TNF-α, IL-6, INF-γ, IL-1β, and IL-17, and increased the expression of IL-10 in the colon, in a CaSR-dependent manner. The CaSR-mediated anti-inflammatory effects of γ-EC were abrogated in β-arrestin2 knock-down Caco-2 cells, and involvement of β-arrestin2 was found to inhibit TNF-α-dependent signaling via cross-talk with the TNF-α receptor (TNFR). ConclusionsThus CaSR activation by γ-EC and γ-EV can aid in maintaining intestinal homeostasis and reducing inflammation in chronic inflammatory conditions such as IBD.

Scoping dietary supplements versus botanical medicines

Scoping dietary supplements <i>versus</i> botanical medicines

Effect of Adrenomedullin Administration in Two Rat Models of Experimental Inflammatory Bowel Disease

Adrenomedullin (AM) is a novel hypotensive peptide that also exerts powerful anti-inflammatory effects. We recently showed that AM significantly reduces the clinical severity of acetic acid-induced colitis, an experimental model of inflammatory bowel disease (IBD) in rats. In the present study, we examined the effect of AM in two alternative rat models of IBD. We found that 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced megacolon development in the saline-treated group, but AM treatment reduced the macroscopic damage caused by TNBS. In the dextran sulfate sodium (DSS) model, treatment with AM reduced diarrhea and bloody stool scores, but did not reduce body weight. Histological analysis revealed that in both the TNBS and DSS models, colon inflammation was much more severe in the saline-treated group than in the AM-treated group. These findings indicate that the anti-inflammatory properties of AM make it an effective therapeutic agent for the treatment of IBD in rats.

Plecanatide and dolcanatide, novel guanylate cyclase-C agonists, ameliorate gastrointestinal inflammation in experimental models of murine colitis.

To evaluate the effect of orally administered plecanatide or dolcanatide, analogs of uroguanylin, on amelioration of colitis in murine models. The cyclic guanosine monophosphate (cGMP) stimulatory potency of plecanatide and dolcanatide was measured using a human colon carcinoma T84 cell-based assay. For animal studies all test agents were formulated in phosphate buffered saline. Sulfasalazine or 5-amino salicylic acid (5-ASA) served as positive controls. Effect of oral treatment with test agents on amelioration of acute colitis induced either by dextran sulfate sodium (DSS) in drinking water or by rectal instillation of trinitrobenzene sulfonic (TNBS) acid, was examined in BALB/c and/or BDF1 mice. Additionally, the effect of orally administered plecanatide on the spontaneous colitis in T-cell receptor alpha knockout (TCRα(-/-)) mice was also examined. Amelioration of colitis was assessed by monitoring severity of colitis, disease activity index and by histopathology. Frozen colon tissues were used to measure myeloperoxidase activity. Plecanatide and dolcanatide are structurally related analogs of uroguanylin, which is an endogenous ligand of guanylate cyclase-C (GC-C). As expected from the agonists of GC-C, both plecanatide and dolcanatide exhibited potent cGMP-stimulatory activity in T84 cells. Once-daily treatment by oral gavage with either of these analogs (0.05-0.5 mg/kg) ameliorated colitis in both DSS and TNBS-induced models of acute colitis, as assessed by body weight, reduction in colitis severity (P < 0.05) and disease activity index (P < 0.05). Amelioration of colitis by either of the drug candidates was comparable to that achieved by orally administered sulfasalazine or 5-ASA. Plecanatide also effectively ameliorated colitis in TCRα(-/-) mice, a model of spontaneous colitis. As dolcanatide exhibited higher resistance to proteolysis in simulated gastric and intestinal juices, it was selected for further studies. This is the first-ever study reporting the therapeutic utility of GC-C agonists as a new class of orally delivered and mucosally active drug candidates for the treatment of inflammatory bowel diseases.

PGRN protects against colitis progression in mice in an IL-10 and TNFR2 dependent manner.

This study was aimed to determine the role and regulation of progranulin (PGRN) in the pathogenesis of inflammatory bowel diseases (IBD). Dextran sulfate sodium (DSS)−, picrylsulfonic acid (TNBS)-induced, bone marrow chimera and CD4+CD45Rbhi T cell transfer colitis model were established and analyzed in wild-type and several genetically-modified mice, including PGRN, IL-10 and TNFR2 deficient mice. Elevated levels of PGRN were found in colitis samples from human IBD patients and mouse colitis models in comparison to the corresponding controls. PGRN-deficient mice became highly susceptible to DSS- and TNBS-induced colitis, whereas recombinant PGRN ameliorated the pathology and reduced the histological score in both DSS and TNBS colitis models. In addition, hematopoietic-derived PGRN was critical for protection against DSS-induced colitis, and lack of PGRN signaling in CD4+ T cells also exacerbated experimental colitis. PGRN-mediated protective effect in colitis was compromised in the absence of IL-10 signaling. In addition, PGRN's effect was also largely lost in the TNFR2-deficient colitis model. Collectively, these findings not only provide the new insight into PGRN's anti-inflammatory action in vivo, but may also present PGRN and its derivatives as novel biological agent for treating IBD.

A novel protocol allowing oral delivery of a protein complement inhibitor that subsequently targets to inflamed colon mucosa and ameliorates murine colitis.

While there is evidence of a pathogenic role for complement in inflammatory bowel disease, there is also evidence for a protective role that relates to host defence and protection from endotoxaemia. There is thus concern regarding the use of systemic complement inhibition as a therapeutic strategy. Local delivery of a complement inhibitor to the colon by oral administration would ameliorate such concerns, but while formulations exist for oral delivery of low molecular weight drugs to the colon, they have not been used successfully for oral delivery of proteins. We describe a novel pellet formulation consisting of cross-linked dextran coated with an acrylic co-polymer that protects the complement inhibitor CR2-Crry from destruction in the gastrointestinal tract. CR2-Crry containing pellets administered by gavage, were characterized using a therapeutic protocol in a mouse model of dextran sulphate sodium (DSS)-induced colitis. Oral treatment of established colitis over a 5-day period significantly reduced mucosal inflammation and injury, with similar therapeutic benefit whether or not the proton pump inhibitor, omeprazole, was co-administered. Reduction in injury was associated with the targeting of CR2-Crry to the mucosal surface and reduced local complement activation. Treatment had no effect on systemic complement activity. This novel method for oral delivery of a targeted protein complement inhibitor will reduce systemic effects, thereby decreasing the risk of opportunistic infection, as well as lowering the required dose and treatment cost and improving patient compliance. Furthermore, the novel delivery system described here may provide similar benefits for administration of other protein-based drugs, such as anti-tumour necrosis factor-α antibodies.

Amelioration of DSS-induced murine colitis by VSL#3 supplementation is primarily associated with changes in ileal microbiota composition.

Inflammatory bowel diseases encompass gastrointestinal illnesses typified by chronic inflammation, loss of epithelial integrity and gastrointestinal microbiota dysbiosis. In an effort to counteract these characteristic perturbations, we used stem cells and/or a probiotic therapy in a murine model of Dextran Sodium Sulfate induced colitis to examine both their efficacy in ameliorating disease and impact on niche-specific microbial communities of the lower GI tract. Colitis was induced in C57BL/6 mice by administering 3% DSS in drinking water for 10 days prior to administering one of three treatment plans: daily probiotic (VSL#3) supplementation for 3 days, a single tail vein injection of 1x106 murine mesenchymal stem cells, or both. Ileal, cecal and colonic sections were collected for microbiota and histological analyses. Microbiota profiling revealed distinct bacterial community compositions in the ileum, cecum and colon of control untreated animals, all of which were predicted in silico to be enriched for a number of discrete KEGG pathways, indicating compositional and functional niche specificity in healthy animals. DSS-treatment perturbed community composition in all three niches with ileal communities exhibiting the greatest change relative to control animals. Each treatment group exhibited treatment-specific alterations in microbiota composition in the lower GI tract, though disease scores were only improved in VSL#3-treated animals. The ileal microbiota were most profoundly altered in composition in this group of animals and characterized by significant Enterobacteriaceae enrichment compared with colitic mice (P < 0.05).

Interleukin-6, but not the interleukin-6 receptor plays a role in recovery from dextran sodium sulfate-induced colitis

Interleukin (IL)-6-deficient, but not IL-6 receptor (IL-6R)-deficient mice present with a delayed skin wound healing phenotype. Since IL-6 solely signals via the IL-6R and glycoprotein 130 (gp130), Il-6r-deficient mice are expected to exhibit a similar phenotype as Il-6-deficient mice. However, p28 (IL-30) and ciliary neurotrophic factor (CNTF) have been identified as additional low-affinity ligands of the IL-6R/gp130/LIFR complex. IL-6 plays an inflammatory and regenerative role in inflammatory bowel disease (IBD). In the present study, we compared Il-6r-deficient mice with mice treated with neutralizing IL-6 monoclonal antibody (mAb) in a model of dextran sodium sulfate (DSS)-induced colitis. Our results, in agreement with those of previous reports, demonstrated that IL-6 mAbs slightly attenuated DSS-induced colitis during the regeneration phase. Il-6r-deficient mice and mice with tissue-specific deletion of the Il-6r in the myeloid cell lineage (LysMCre) with acute and chronic DSS-induced colitis were, however, indistinguishable from wild-type mice. Our data suggest that IL-6 and IL-6R have an additional role in colitis, apart from the IL-6/IL-6R classic and trans-signaling.

Laser Acupuncture Treatment on the Five Transport Points of the Spleen Meridian in Dextran-Sulfate-Sodium-Induced-Colitis in Rats

Objectives : The purpose of this study is to compare the effects of laser acupuncture to the 830 nm on the five transport points with the spleen meridian for treatment to intestinal disease in rat with dextran sulfate sodium(DSS)-induced colitis. Methods : Colitis was induced by DSS for 20 days. The laser therapy on the five transport points of spleen meridian (Laser Well Point-SP1(L-WE), Laser Brook Point-SP2(L-BR), Laser Stream Point-SP3(L-ST), Laser River Point-SP5(L-RI) and Laser Sea Point-SP9(L-SE) was practiced twice a week for 5 times. Colon length was measured using a measuring point. Histological evaluation of colitis was conducted by hematoxylin and eosin(H&E) staining. Reverse transcription polymerase chain reaction(RT-PCR) was determined using western blotting and quantitative reverse-transcriptase polymerase chain reaction, respectively. Results: Colon length increased significantly L-BR and L-ST points after 5 times of therapy. Damage to the colonic mucosa is an integral feature of the DSS model, so control colonic mucosa tissue was damaged in the areas of ulceration resulting in complete epithelial loss. However histological damage decreased on the epithelial lining at all points. Cyclooxygenase(COX)-2 concentrations decreased in all points groups and Interferon(IFN)- increased in L-WE, L-BR, L-RI and L-SE points but L-ST was decreased when compared with control. White blood cell(WBC) and neutrophils(NE) decreased after the fifth acupuncture on the all points. But hemoglobin(HGB) increased after the fifth acupuncture on the L-WE, L-BR, L-ST and L-RI points. Also Mean corpuscular hemoglobin(MCH) and Mean corpuscular hemoglobin concentration(MCHC) decreased after the fifth acupuncture on the all points. Conclusions: The present study indicated that five transport points of the spleen meridian can prevent the development of DSS-induced colitis in rat. Thereby suggesting that should be available for decreasing DSS-induced inflammation in a colonic mucosa of tissue.

Macrophage migration inhibitory factor has a role in controlling colorectal cancer (TUM4P.918)

Abstract Chronic Inflammation has been related with cancer development by counteracting and unbalancing the immune response. The inflammatory cytokine macrophage migration inhibitory factor (MIF) is overexpressed in many carcinogenic tumors, stimulates angiogenesis and metastasis promoting proliferation and survival in malignant cells. In the inflammatory disease ulcerative colitis, MIF is early expressed and favors the inflammatory cytokine production like TNF-α and IL-1β. As intestinal chronic inflammation may proceed to colorectal cancer, we are interested in determining the role of MIF on development and pathology on colorectal cancer. To elucidate this point we used MIF-KO and WT mice, both with BALB/c genetic background, to develop a colorectal cancer model of Dextran Sodium Sulfate and Azoxymethan. As expected, MIF-KO mice showed low levels of serum inflammatory cytokines TNF-α, IL-1β and IFN-γ compare to WT mice. Strikingly, we found significantly more tumors and in a higher development stage on MIF-KO mice (24.4+/-2) compared to WT mice (12.6+/-2). Higer numbers of CD4+ cells were detected in intestinal epithelial cells on WT mice compared to MIF-KO mice. Therefore, although MIF has been recognized as a promoter of inflammation, which could favor the development of cancer, our results suggest that MIF is involved in controlling the development of colorectal cancer, possibly by its chemokine properties.

Mucosal gene therapy using a pseudotyped lentivirus vector encoding murine interleukin-10 (mIL-10) suppresses the development and relapse of experimental murine colitis

BackgroundTherapeutic gene transfer is currently being evaluated as a potential therapy for inflammatory bowel disease. This study investigates the safety and therapeutic benefit of a locally administered lentiviral vector encoding murine interleukin-10 in altering the onset and relapse of dextran sodium sulfate induced murine colitis.MethodsLentiviral vectors encoding the reporter genes firefly-luciferase and murine interleukin-10 were administered by intrarectal instillation, either once or twice following an ethanol enema to facilitate mucosal uptake, on Days 3 and 20 in Balb/c mice with acute and relapsing colitis induced with dextran sulfate sodium (DSS). DSS colitis was characterized using clinical disease activity, macroscopic, and microscopic scores. Bioluminescence optical imaging analysis was employed to examine mucosal lentiviral vector uptake and transgene expression. Levels of tumor necrosis factor-α and interleukin-6 in homogenates of rectal tissue were measured by ELISA. Biodistribution of the lentiviral vector to other organs was evaluated by real time quantitative PCR.ResultsMucosal delivery of lentiviral vector resulted in significant transduction of colorectal mucosa, as shown by bioluminescence imaging analysis. Lentiviral vector-mediated local expression of interleukin-10 resulted in significantly increased levels of this cytokine, as well as reduced levels of tumor necrosis factor-α and interleukin-6, and significantly reduced the clinical disease activity, macroscopic, and microscopic scores of DSS colitis. Systemic biodistribution of locally instilled lentiviral vector to other organs was not detected.ConclusionsTopically-delivered lentiviral vectors encoding interleukin-10 safely penetrated local mucosal tissue and had therapeutic benefit in this DSS model of murine colitis.