Dextran sulphate sodium-induced colitis is ameliorated in interleukin 4 deficient mice

The importance of IL-4 and its effects in inflammatory bowel disease (IBD) was studied using the dextran sulphate sodium-induced model of experimental colitis. The model resembles ulcerative colitis in humans. IL-4 deficient mice and IL-4+/+ littermates were used to induce colitis. Activity of disease, extent of tissue damage, immunoglobulin isotypes, IFNgamma and IL-10 production was assessed. Both disease activity index (DAI) and histological scores were consistently lower in the IL-4 deficient mice than in the IL-4+/+ littermates. Furthermore, the lower histological scores reflected the milder inflammatory lesions and decreased ulceration found in the IL-4 deficient mice. Analysis of immunoglobulin subtypes showed that IgG1 was almost absent in the sera of IL-4 deficient mice. IFNgamma contents was much higher in colonic tissues from IL-4 deficient mice. Dextran sulphate sodium-induced colitis is ameliorated in IL-4 deficient mice. IL-4 either directly or through its effects on T and B cells influences its severity. It is unclear if the higher immunoglobulin-producing cells in the colonic tissues of IL-4 deficient mice before colitis was induced could have influenced the outcome of the disease. The high IFNgamma contents in colonic tissues of IL-4 deficient mice argue against the role of this cytokine as a crucial mediator of tissue damage during the acute phase of colitis.     

Suppressive effect of berberine on experimental dextran sulfate sodium-induced colitis

The anti-inflammatory effect of berberine was evaluated in murine model of acute experimental colitis induced by dextran sulfate sodium (DSS). Berberine, given orally at 40, 20, 10?mg/kg for 10 days, ameliorated all the supposed inflammatory symptoms of the induced colitis, such as body weightloss, blood hemoglobin reduction, high myeloperoxidase levels, and malondialdehyde content-inflamed mucosa. Furthermore, the cytokine production of splenic lymphocytes was analyzed. The results showed the IFN-γ and IL-12 were increased, but IL-4 and IL-10 were decreased in DSS-induced colitis,when those were compared with the normal control. But the administration of berberine to DSS-induced colitis mice showed lower production of IFN-γ and IL-12 and higher production of IL-4 and IL-10 than the DSS-induced colitis mice. The results suggest that the protective effects of berberine against the DSS-induced colitis may be associated with the regulation of cytokine production.     

Suppressive effect of berberine on experimental dextran sulfate sodium-induced colitis

The anti-inflammatory effect of berberine was evaluated in murine model of acute experimental colitis induced by dextran sulfate sodium (DSS). Berberine, given orally at 40, 20, 10?mg/kg for 10 days, ameliorated all the supposed inflammatory symptoms of the induced colitis, such as body weightloss, blood hemoglobin reduction, high myeloperoxidase levels, and malondialdehyde content-inflamed mucosa. Furthermore, the cytokine production of splenic lymphocytes was analyzed. The results showed the IFN-γ and IL-12 were increased, but IL-4 and IL-10 were decreased in DSS-induced colitis,when those were compared with the normal control. But the administration of berberine to DSS-induced colitis mice showed lower production of IFN-γ and IL-12 and higher production of IL-4 and IL-10 than the DSS-induced colitis mice. The results suggest that the protective effects of berberine against the DSS-induced colitis may be associated with the regulation of cytokine production.     

Dextran sulfate sodium-induced acute colonic inflammation in angiotensin II type 1a receptor deficient mice

Objective: Angiotensin II (Ang II) receptor blockers have been reported to contribute to cytoprotective effects in various organs. However, the role of renin-angiotensin system (RAS) in modulation of the inflammatory bowel disease (IBD) remains unclear. In this study we assessed the role of angiotensin II type 1a (AT1a) receptor on the outcome of dextran sulfate sodium (DSS)-induced acute colitis by employing AT1a receptor deficient mice. Materials and methods: The acute colitis was induced in wild type (WT) and AT1a receptor deficient mice by giving orally 3% DSS in drinking water for 7 days. Results: Induction of DSS colitis resulted in up-regulation of Ang II and AT1a receptor in the colonic mucosa of WT mice. In parallel, loss of body weight, an increase in disease activity index (DAI), and the shortening of colon were found in DSS-challenged WT mice. In addition, an increase in thiobarbituric acid (TBA)-reactive substances and myeloperoxidase (MPO) activity, along with the up-regulation of tumor necrosis factor (TNF)-α were detected in the colonic mucosa of DSS-challenged WT mice. The endpoints mentioned above were significantly ameliorated in DSS-challenged AT1a receptor deficient mice. Conclusions: RAS is involved in the pathophysiology of DSS-induced colitis and AT1a receptor may be a novel therapeutic target for the treatment of IBD. Received 11 May 2007; returned for revision 12 July 2007; accepted by M. Katori 19 September 2007     

Nitric oxide supplementation ameliorates dextran sulfate sodium-induced colitis in mice

Nitric oxide (NO) synthesis is up-regulated in inflammatory bowel disease. However, its role in the pathophysiology of this condition is controversial. The aims of this study were to assess whether nitric oxide administration ameliorates experimental colitis and to determine the possible mechanisms underlying its effects on intestinal inflammation. For this purpose, the NO donor diethylamine NONOate (DETA/NO; 0.01, 0.1, 1, 5, or 10 mg/kg/day), or the DETA moiety, was administered daily to mice with dextran sulfate sodium-induced colitis. Daily body weight and colonic pathologic alterations at Day 10 were determined. Leukocyte endothelial cell interactions in colonic venules were assessed with intravital microscopy, and expression of endothelial cell adhesion molecules was determined using radiolabeled antibodies. IL-12 and IFN-gamma production were measured in intestinal tissue. Colitis induced a significant loss of body weight, reduction of colon length, and increase in colon weight and myeloperoxidase activity. Administration of 1 mg/kg/day DETA/NO significantly attenuated these pathologic changes. The marked increase in leukocyte rolling and adhesion in colonic venules of colitic mice were significantly reduced by administration of 1 mg/kg/day DETA/NO. Development of colitis was associated with a marked increase in endothelial expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and P-selectin. Supplementation with NO significantly attenuated the up-regulation of endothelial intercellular adhesion molecule-1 and P-selectin, but not vascular cell adhesion molecule-1, in colonic tissue. NO abrogated the increase in IL-12 and IFN-gamma mRNA expression in the colon of colitic mice. The DETA moiety alone did not have any effect on any of the parameters studied. In conclusion, exogenous NO supplementation significantly ameliorates dextran sulfate sodium-induced colitis. This effect is related to a reduction in leukocyte recruitment and proinflammatory cytokine production.     

Effect of processed Scutellaria baicalensis on dextran sulfate sodium-induced colitis in mice

Scutellaria baicalensis Georgi (Labiatae) has been used in the treatment of inflammatory diseases. Drug processing (Poje) is the process of treating crude drugs by several methods before use. The aim of this study was to determine the effect of processed Scutellaria baicalensis on experimental ulcerative colitis induced by dextran sulfate sodium (DSS). The types of processed Scutellaria baicalensis used in this study were parched Scutellaria baicalensis (PS) and rice wine-baked Scutellaria baicalensis (RWBS). Experimental colitis was induced in mice using a daily treatment of 5% DSS in the drinking water for 7 days. The water extracts of processed Scutellaria baicalensis (1 g/kg) were administered orally once a day for 7 days. The mice were divided in four groups: i) water plus DSS group, ii) crude Scutellaria baicalensis (CS) plus DSS group, iii) PS plus DSS group, and iv) RWBS plus DSS group. RWBS ameliorated all of the inflammatory symptoms, such as body weight loss, rectal bleeding and histological damage, compared to CS. Furthermore, RWBS significantly reduced the mucosal myeloperoxidase activity, and TNF-alpha (tumor necrosis factor-alpha), COX-2 (cyclooxygenase-2), NF-kappaB (nuclear factor-kappa B) and chymase expression more than CS. But these effects were not shown in the PS plus DSS group. Efficacy of Scutellaria baicalensis was increased after rice wine baking, but not after parching. The findings in this study suggest that RWBS may be a useful therapeutic agent for ulcerative colitis.     

大肠埃希氏菌在葡聚糖硫酸钠诱导的结肠炎恢复中的作用

目的: 随着对炎症性肠病(inflammatory bowel disease,IBD) 发病机制的深入研究, 肠道正常菌群与肠道炎症的密切关系日益受到重视。本研究旨在评价肠道大肠埃希氏菌( E.coli )对葡聚糖硫酸钠(dextran sulfate sodium,DSS) 诱导的小鼠结肠炎肠道黏膜的保护作用及其可能机制。方法: BALB/c 小鼠饮用含 3.5%DSS的饮用水 5 d, 诱导小鼠急性结肠炎, 模拟人类溃疡性结肠炎。 空白对照组饮用未添加 DSS的饮用水。饮用DSS的小鼠随机分为 3组, 分别给予不同的处理: (1) 单纯DSS 处理组; (2) 细菌耗竭小鼠(bacteria-depleted mice,BD小鼠)单纯DSS处理组; (3) 细菌耗竭小鼠大肠埃希氏菌处理组。从 4方面评价各组的处理反应: (1) 一般情况: 包括体重、疾病活动度(disease activity index, DAI)评分、结肠长度和重量; (2) 组织病理评分;(3) 化学比色法检测病变组织髓过氧化物酶(myeloperoxidase,MPO) 活性; (4) 免疫组织化学方法检测活化的核转录因子-κΒ(nuclear factor kappa B,NF-κB)。结果: 无E.coli处理的细菌耗竭小鼠难以从DSS诱导的肠炎中恢复。E.coli处理组和无E.coli处理组比较,大体评分、 组织病理评分和MPO活性明显改善(P<0.05)。E.coli处理组NF-κB活性显著高于无E.coli处理组 (均P<0.05)。结论: 肠道正常菌群是肠道炎症恢复的必需条件。大肠埃希氏菌能够促进小鼠DSS结肠炎的恢复;该作用与促进NF-κB的活化有关。     

Suppressive effect of non-anaphylactogenic anti-IgE antibody on the development of dextran sulfate sodium-induced colitis

Inflammatory bowel disease (IBD) is a spectrum of immune-mediated chronic disorders of the intestine. Patients with IBD tend to exhibit significantly elevated levels of IgE in their serum. In general, the pathogenesis of IBD exhibits inflammatory events such as immunoglobulin E (IgE)-mediated hypersensitivity. We examined the effect of the non-anaphylactogenic anti-IgE antibody, which has been known to block IgE functions, in an animal model of ulcerative colitis induced by the oral intake of dextran sulfate sodium (DSS) for seven days. The non-anaphylactogenic anti-IgE antibody was subcutaneously injected on day 0 of DSS treatment. The disease activity index (DAI) was calculated by scoring intestinal states, including body weight loss, diarrhea, and rectal bleeding, and the activities of myeloperoxidase (MPO) and chymase were measured in the colon tissue. In addition, the expression of tumor necrosis factor (TNF)-alpha and cyclooxygenase (COX)-2 was determined by Western blotting. Administration of the anti-IgE antibody markedly reduced the histological damage to the colon and the DAI increment exhibited by the DSS-induced colitis. The anti-IgE antibody also significantly suppressed the activities of MPO and chymase as well as the expression of TNF-alpha and COX-2 in the DSS-treated colon tissue. Furthermore, the elevation of IgE levels in serum was induced by DSS and reduced by anti-IgE antibody injection. Thus, these results indicate that the IgE response played an important role in the clinical signs and the expression of inflammatory mediators in a colitis model caused by DSS treatment, suggesting that the non-anaphylactogenic anti-IgE antibody may be a useful therapeutic agent for ulcerative colitis.     

Glucosamine, a naturally occurring amino monosaccharide, suppresses dextran sulfate sodium-induced colitis in rats

Glucosamine, a naturally occurring amino monosaccharide, is widely used to treat osteoarthritis in humans. Furthermore, glucosamine exhibits an anti-inflammatory action by inhibiting the activation of neutrophils, chondrocytes and synoviocytes. Recently, we revealed that glucosamine suppresses cytokine-induced activation of intestinal epithelial cells in vitro. In the present study therefore, we investigated whether glucosamine exhibits the anti-inflammatory effect in vivo, using dextran sulfate sodium (DSS)-induced colitis in rats, a model of inflammatory bowel diseases (IBD). The results indicated that glucosamine improved the clinical symptoms (evaluated by disease activity index), and suppressed colonic inflammation (evaluated by colon length and weight/length ratio) and tissue injury (evaluated by histological damage score) in DSS-induced colitis. Furthermore, glucosamine inhibited the activation of intestinal epithelial cells, as evidenced by the suppressed phosphorylation of NF-kappaB in the intestinal mucosa of DSS-induced colitis. Collectively, these observations suggest that glucosamine is likely to suppress the activation of intestinal epithelial cells in vivo, thereby possibly exhibiting anti-inflammatory action in a DSS-induced rat colitis model. Thus, glucosamine could prove to be a useful agent for IBD.     

Clostridium butyricum, a probiotic derivative, suppresses dextran sulfate sodium-induced experimental colitis in rats

Recent studies have suggested that probiotics or short chain fatty acids (SCFAs) exert a therapeutic effect on inflammatory bowel disease (IBD) patients. In a previous study, we demonstrated that Clostridium butyricum produces high levels of SCFAs in culture. In addition, a yogurt-based additive effectively masked, completely eliminating the unpleasant odor derived from the SCFAs. We recently reported that the oral administration of both high and low dose diets (50% w/w for 17 days and 5% w/w for 16 months, respectively) of the Clostridium butyricum derivative did not cause pathological abnormalities in rats. In the present study, we evaluated the effects of this product against dextran sulfate sodium (DSS)-induced experimental colitis in rats. Five-week-old male Wistar Hannover GALAS rats were given a mixture of a standard diet containing 3% (w/w) of DSS for 8 days. In the derivative-fed group, Clostridium butyricum derivative (20% w/w) with 0.1% (w/w) additive was also added to their diet. The control-fed group was given tap water (20% w/w) with 0.1% (w/w) additive. After 8 days, a laparotomy was performed, and macroscopic and microscopic inflammation scoring was determined. The Clostridium butyricum derivative effectively prevented bloody diarrhea. In addition, mucosal damage to the derivative-fed group was significantly reduced macroscopically compared to that of the control-fed group. The potential clinical efficacy of the Clostridium butyricum derivative in IBD patients is also discussed.     

The free radical scavenger edaravone suppresses experimental dextran sulfate sodium-induced colitis in rats

Recent studies suggest that the enhanced release of reactive oxygen species (ROS) plays an important role in the pathogenesis of clinical inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease. In the present study, we investigated the effects of the free radical scavenger edaravone, which is used clinically as an anti-stroke agent, in the development of experimental dextran sulfate sodium (DSS)-induced colitis in rats. The rats were fed 4% (w/w of diet) DSS in standard powder chow for 8 days. The edaravone and vehicle saline were injected subcutaneously twice a day. After the experimental period, the wet colonic weight, macroscopic mucosal damaged area, histological damage score, mucosal myeloperoxidase (MPO) activity, mucosal tissue lipid peroxidate and serum interleukin-6 (IL-6) levels were measured. In the DSS-induced colitis model, edaravone treatment (1-20 mg/kg day) significantly reduced the wet colonic weight, macroscopic damaged area, and the histological damage score. Edaravone treatment also reduced mucosal MPO activity, mucosal tissue lipid peroxidate level and serum IL-6 level. In particular, edaravone at a dose of 20 mg/kg day significantly reduced mucosal MPO activity and serum IL-6 level. These results strongly support the involvement of ROS in the pathogenesis of DSS-induced colitis. A clinical effect for edaravone against IBD patients is strongly expected.     

Differential dose effects of recombinant IL-25 on the development of dextran sulfate sodium-induced colitis

Objective  

We evaluated different dose effects of rIL-25 on acute ulcerative colitis.     

Tapeworm infection reduces epithelial ion transport abnormalities in murine dextran sulfate sodium-induced colitis

The rat tapeworm Hymenolepis diminuta was used to test the hypothesis that helminth infection could modulate murine colitis. Mice were infected with five H. diminuta cysticercoids, and colitis was evoked via free access to 4% (wt/vol) dextran sulfate sodium (DSS)-containing drinking water for 5 days. BALB/c mice were either infected with H. diminuta and 7 days later exposed to DSS (prophylactic strategy) or started on DSS and infected with H. diminuta 48 h later (treatment strategy). Naive and H. diminuta-only-infected mice served as controls. On autopsy, colonic segments were processed for histological examination and myeloperoxidase (MPO) measurement or mounted in Ussing chambers for assessment of epithelial ion transport. Cytokines (gamma interferon [IFN-gamma], interleukin 12 [IL-12], and IL-10) were measured in serum and colonic tissue homogenates. DSS treatment resulted in reduced ion responses (indicated by short-circuit current [Isc]) to electrical nerve stimulation, the cholinergic agonist carbachol, and the adenylate cyclase activator forskolin compared to controls. H. diminuta infection, either prophylactic or therapeutic, caused a significant (P < 0.05) amelioration of these DSS-induced irregularities in stimulated ion transport. In contrast, the histopathology (i.e., mixed immune cell infiltrate, edema, and ulcerative damage) and elevated MPO levels that accompany DSS colitis were unaffected by concomitant H. diminuta infection. Similarly, there were no significant differences in levels of IFN-gamma, IL-12, or IL-10 in serum or tissue from any of the treatment groups at the time of autopsy. We suggest that abolishment of colitis-induced epithelial ion transport abnormalities by H. diminuta infection provides proof-of-principle data and speculate that helminth therapy may provide relief of disease symptoms in colitis.     

Suppressive effects of a new anti-inflammatory agent, IS-741, on dextran sulfate sodium-induced experimental colitis in rats

A novel anti-inflammatory drug, IS-741, blocked the adhesion of inflammatory cells to microvascular endothelial cells in vivo and in vitro. We examined the efficacy of IS-741 in a dextran sulfate sodium (DSS)-induced colitis model. DSS colitis was induced by the oral administration of 3% DSS for 10 days in rats. The rats were then divided in two groups: a 1% DSS plus IS-741 group and a 1% DSS plus water group. IS-741 was dissolved in water and administered orally (10 mg/kg) once per day for 14 days. The rats treated with DSS plus IS-741 remained healthy, and their body weight increased. The wet weight of the colon was significantly lower and the total colon length was significantly longer in the IS-741-treated group. Histological examinations revealed a marked infiltration of inflammatory cells into both the mucosa and submucosa in the DSS plus water group, but these changes were attenuated in the IS-741-treated group. The mucosal damage score was significantly reduced by treatment with IS-741. IS-741 also significantly reduced the mucosal myeloperoxidase activity. FACS analysis revealed that IS-741 significantly reduced Mac-1 expression on blood neutrophils. In conclusion, IS-741 suppressed DSS-induced experimental colitis in rats. Some of the action of IS-741 may be associated with its inhibitory effects on the Mac-1 expression of neutrophils in association with the blockade of their adhesion to endothelial cells. The findings in this study suggest that IS-741 may be a useful new therapeutic agent for inflammatory bowel disease.     

Effect of rectal administration of rebamipide on dextran sulfate sodium-induced colitis: Role of hepatocyte growth factor

Objective and design: Since rebamipide is effective for the treatment of ulcerative colitis (UC), we examined the involvement of hepatocyte growth factor (HGF) in the action of rebamipide. Materials: Fifty-five and forty female Balb/c mice, respectively, were used in Exp. 1 and 2. Treatment: 50 mg/kg/day rebamipide (Exp. 1) and 1 × 10⁷ pfu pAxCAHGF (the CAG promoter-driving HGF gene in adenovirus vector) (Exp. 2) were intrarectally introduced after induction of colitis by 4 % dextran sulfate sodium (DSS). Methods: Therapeutic effects were assessed by cell proliferation and apoptosis. Results: Rebamipide caused proliferation of epithelial cells at 10 days after treatment, and decreased apoptosis at 10, 14 and 21 days, compared with controls. Expression of HGF was greatly increased in rebamipide-treated mice. pAxCAHGF caused cell proliferation and apoptosis, which showed the same pattern as with rebamipide treatment. Conclusions: Rectal administration of rebamipide is effective for DSS-induced colitis in association with induction of HGF. Received 17 June 2006; returned for revision 23 August 2006; returned for final revision 29 October 2006; accepted by I. Ahnfelt-R?nne 14 December 2006     

The free radical scavengers edaravone and tempol suppress experimental dextran sulfate sodium-induced colitis in mice

Recent studies have suggested that the enhanced release of reactive oxygen species (ROS) plays an important role in the pathogenesis of clinical inflammatory bowel disease (IBD), such as ulcerative colitis and Crohn's disease. In the present study, we investigated the effects of the free radical scavengers edaravone and tempol in the development of experimental dextran sulfate sodium (DSS)-induced colitis in mice. Male BALB/cA mice were fed 4% (w/w of diet) DSS in standard powder chow for 8 days. Edaravone, tempol, or vehicle saline were then injected subcutaneously twice per day. After the experimental period, the colonic length, histological damage score, and mucosal myeloperoxidase (MPO) and serum interleukin-6 (IL-6) levels were measured. Edaravone (15 mg/kg/day) and tempol (5-15 mg/kg/day) suppressed the colonic shortening and the damage score. In particular, tempol at 15 mg/kg/day significantly attenuated the colonic shortening and damage score. Edaravone and tempol suppressed the serum IL-6 levels, and significantly suppressed the increased colonic MPO levels. These results strongly support the involvement of ROS in the pathogenesis of DSS-induced colitis. A clinical effect for edaravone and tempol in IBD patients is strongly expected.     

Interleukin-33 suppresses Notch ligand expression and prevents goblet cell depletion in dextran sulfate sodium-induced colitis

Interleukin (IL)-33 is a cytokine belonging to the IL-1 family. IL-33 plays an important role in Th2 immune responses, and induces goblet cell hyperplasia in the intestinal mucosa. In this study, to elucidate the molecular mechanisms underlying IL-33-induced goblet cell hyperplasia, we investigated how IL-33 modulates the Notch signaling pathway in dextran sulfate sodium (DSS)-induced experimental colitis. DSS colitis was induced in BALB/c mice with intraperitoneal administrations of IL-33 (1 μg/body) every 48 h. Tissue samples were evaluated by standard immunohistochemical procedures. The mucosal mRNA expression of the Notch ligands was analyzed by a real-time polymerase chain reaction. The mucosal mRNA expression of Notch ligands [Jagged1 (Jag1) and Delta-like (Dll) 1 and 4] was significantly increased in DSS-colitis mice. IL-33-induced goblet cell hyperplasia in the control mice. In the DSS-colitis mice, the goblet cells were depleted in the colon, but IL-33 completely prevented goblet cell depletion in the DSS-colitis mice. IL-33 induced a significant decrease in Jag1 and Dll4 mRNA expression in the mucosa of the control mice. Mucosal mRNA expression for Jag1, Dll1 and 4 was significantly elevated in the DSS-colitis mice, but this elevation was significantly blocked by the administration of IL-33. IL-33 dose-dependently decreased Jag1 mRNA expression in mouse colonic subepithelial myofibroblasts. In contrast to its preventive effects on goblet cell depletion, IL-33 aggravated DSS colitis. IL-33 prevented goblet cell depletion via its inhibitory actions against Notch ligand expression in DSS colitis, but exacerbated the disease activity. IL-33 plays two counter actions in mucosal inflammation; the first is a protective action via goblet cell induction, and the second is a pro-inflammatory action as a Th2 cytokine.