Polaprezinc (N-(3-aminopropionyl)-L-histidinato zinc) ameliorates dextran sulfate sodium-induced colitis in mice

OBJECTIVE: Polaprezinc (N-(3-Aminopropionyl)-L-histidinato zinc), an anti-ulcer drug, has been reported to have an anti-inflammatory action in several inflammatory diseases. The aim of this study was to investigate the effect of polaprezinc on dextran sulfate (DSS)-induced colitis in mice. MATERIAL AND METHODS: Mice with colitis induced by DSS were intrarectally treated with polaprezinc (15 mg/kg) or zinc sulfate (7.5 mg/kg) every day after the administration of DSS for 7 days. Disease activity index (DAI) and histological tissue damage were assessed. Levels of myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma in the colon were measured. Expression of heat shock protein (HSP) 25 and HSP70 in the colon was analyzed by Western blot analysis. RESULTS: DAI and histological scores were remarkably reduced in polaprezinc-treated mice with DSS-induced colitis. Polaprezinc suppressed the increase of MPO activity and the production of TNF-alpha and IFN-gamma in the colon tissues of mice with DSS-induced colitis. Expression of HSP25 and HSP70 was remarkably up-regulated in the colon tissues of polaprezinc-treated mice during DSS treatment. CONCLUSIONS: Polaprezinc suppresses DSS-induced colitis in mice, partly through inhibition of production of pro-inflammatory cytokine, suppression of neutrophils accumulation and cytoprotection by overexpression of HSPs. Polaprezinc could be useful in the treatment of inflammatory bowel diseases.     

Curcumin Prevents the Development of Dextran Sulfate Sodium (DSS)-Induced Experimental Colitis

Curcumin is a phenolic natural product isolated from the rhizome of Curcuma longa (turmeric). We evaluated the effects of curcumin on the development of dextran sulfate sodium (DSS)-induced experimental colitis. BALB/c mice were fed a chow containing either 3.5% (wt/wt) DSS or 3.5% DSS + 2.0% (wt/wt) curcumin. The body weight loss was more apparent in DSS-treated mice than in DSS + curcumin-treated mice. The disease activity index, histological colitis score, and MPO activity were all significantly higher in DSS-treated mice than in DSS plus curcumin-treated mice. Microscopically, mucosal edema, cellular infiltration, and epithelial disruption were much more severe in DSS-treated mice than in DSS + curcumin-treated mice. In DSS + curcumin-treated mice, NF-κB activation was blocked in the mucosa. In conclusion, the development of DSS-induced colitis was significantly attenuated by curcumin. Being a nontoxic natural dietary product, curcumin could be useful in treatment of IBD patients.     

慢性应激对小鼠溃疡性结肠炎的影响

目的观察慢性束缚应激对葡聚糖酸钠(DSS)诱导的小鼠溃疡性结肠炎(UC)的影响。方法64只BALB/C小鼠分为6组,单纯应激组、正常对照组各16只,应激 2DSS组、应激 4DSS组、2DSS组、4DSS组各8只。采用自制的束缚笼对应激组小鼠建立慢性心理应激动物模型。采用小鼠自由饮用DSS溶液的方法建立UC模型。每日观察各组疾病活动指数(DAI)。并在实验结束后测量结肠组织损伤评分(HS)、髓过氧化物酶(MPO)活性。HS评分通过在光镜下观察结肠组织学改变得出。并用分光光度法测定结肠组织中MPO的活性。结果单纯应激组小鼠体重增长较正常对照组缓慢(P<0.05)。4DSS组小鼠DAI评分、HS评分及结肠组织MPO活性均较正常对照组增高(P<0.05)。应激 4DSS组上述指标较正常对照组变化更显著,与4DSS组比较亦增高(P<0.05)。2DSS组上述指标与正常对照组相比无明显区别(P>0.05)。应激 2DSS组上述指标较正常对照组增高(P<0.05)。结论慢性束缚应激可以使小鼠发生UC的易感性增加并加重DSS结肠炎的病理损伤。     

A recombinant cystatin from Ascaris lumbricoides attenuates inflammation of DSS‐induced colitis

Helminthiasis may ameliorate inflammatory diseases, such as inflammatory bowel disease and asthma. Information about immunomodulators from Ascaris lumbricoides is scarce, but could be important considering the co‐evolutionary relationships between helminths and humans. We evaluated the immunomodulatory effects of a recombinant cystatin from A. lumbricoides on an acute model of dextran sodium sulphate (DSS)‐induced colitis in mice. From an A. lumbricoides cDNA library, we obtained a recombinant cystatin (rAl‐CPI). Protease activity inhibition was demonstrated on cathepsin B and papain. Immunomodulatory effects were evaluated at two intraperitoneal doses (0.5 and 0.25 μg/G) on mice with DSS‐induced colitis. Body weight, colon length, Disease Activity Index (DAI), histological inflammation score, myeloperoxidase (MPO) activity, gene expression of cytokines and cytokines levels in colon tissue were analysed. Treatment with rAl‐CPI significantly reduced DAI, MPO activity and inflammation score without toxic effects. Also, IL‐10 and TGF‐B gene overexpression was observed in rAl‐CPI‐treated group compared to DSS‐exposed control and healthy mice. Furthermore, a reduction in IL‐6 and TNF‐A expression was found, and this was confirmed by the levels of these cytokines in colonic tissue. In conclusion, rAl‐CPI reduces inflammation in a mouse model of DSS‐induced colitis, probably by increasing the expression of anti‐inflammatory cytokines and reducing pro‐inflammatory ones.     

Oral administration of mesalazine protects against mucosal injury and permeation in dextran sulfate sodium-induced colitis in rats

Abstract

Objective. Mesalazine, from which 5-aminosalicylic acid is released, is a therapeutic drug for inflammatory bowel disease. There has been no study concerning the effect of orally administered mesalazine on dextran sodium sulfate (DSS)-induced colitis in the rat model of ulcerative colitis. Material and methods. Colitis was evaluated by means of the length of the colon, white blood cell count (WBC), tissue myeloperoxidase (MPO) activity, and histological inflammation scores. Colonic mucosal permeation was evaluated using Evans blue. The localization of a tight junction protein, occludin, was evaluated immunohistochemically and examined using confocal laser scanning microscopy. Results. Mesalazine significantly improved changes in the length of the colon, tissue MPO activity, WBC, and the histological inflammation score as compared with DSS-induced colitis. Furthermore, the drug completely inhibited the increased permeation in DSS-induced colitis in rats. The immunofluorescence signals of occludin were disrupted and irregularly distributed in DSS-induced colitis, while the signals appeared as a typical reticular pattern but with reduced intensity by the administration of mesalazine, without any reduction in the protein content. In addition, the oral administration of mesalazine significantly improved mucosal permeation, thereby protecting the intestinal mucosa against injury in DSS-induced colitis in rats. Conclusions. These findings suggest that the recovery of mucosal impairment due to treatment with mesalazine may be associated with the protection of the tight junction protein occludin in DSS-induced colitis.     

Effect of N-acetylcysteine on the Murine Model of Colitis Induced by Dextran Sodium Sulfate Through Up-Regulating PON1 Activity

Reactive oxygen species (ROS) are increased in inflammatory bowel disease (IBD) and have been implicated as mediators of intestinal inflammation. We investigated the hypothesis that N-acetylcysteine (NAC) as a glutathione (GSH) precursor attenuates disease progression in a murine dextran sodium sulfate (DSS)-induced colitis model. A colitis model was induced by adding 5% DSS into the drinking water for 7 days. BALB/c mice were injiciatur enema with saline, 5-ASA, N-acetylcysteine, respectively, and free drinking water as control group. DSS-treated mice developed severe colitis as shown by bloody diarrhea, weight loss, and pathologic involvement. Colon lengths were significantly decreased in DSS-treated mice with decreased GSH activity too (P < 0.01). ROS in the colon, the level of interleukin 1β (IL-1β) in colonic mucosa, serum tumor necrosis factor a (TNF-α), MPO, and MDA were significantly increased in DSS-treated animals (P < 0.01), with decreased PON1 activity (P < 0.01). However, NAC significantly decreased colonic MPO activity, ROS, TNF-α and IL-1β levels and increased PON1 activity and GSH concentration. Moreover, NAC attenuated the macroscopic colonic damage and the histopathologic changes-induced by DSS while similar to 5-ASA group. These results suggest that NAC may be effective in the treatment of colitis through its up-regulating PON1 and scavenging oxygen-derived free radicals.     

Therapeutic effects of four strains of probiotics on experimental colitis in mice

AIM： To investigate the therapeutic effects of four strains of probiotics （E. feacalis, L. acidophilus, C. butyricum and B. adolescentis） on dextran sulphate sodium （DSS）-induced experimental colitis in Balb/c mice. METHODS： Eighty Balb/c mice were randomly divided into 8 groups. Weight-loss, fecal character, fecal occult blood and hematochezia were recorded daily. Disease activity index （DAI） scores were also evaluated everyday. Length of colon was measured and histological scores were evaluated on the 13th day. Myeloperoxidase （MPO） activity was detected. Interleukin-1 （IL-1） and IL-4 expression was detected by ELISA and RT-PCR. RESULTS： The four strains of probiotics relieved the inflammatory condition of DSS-induced experimental colitis in mice. Weight loss was slowed down in all probiotics-treated mice. Even weight gain was observed by the end of probiotics treatment. The DAI and histological scores of probiotics-treated mice were lower than those of mice in the control group （1.9 ± 0.2 vs 8.6 ± 0.4, P 〈 0.05 for E. faecalis）. The length of colon of probiotics-treated mice was longer than that of mice in the control group （10.3 ± 0.34 vs 8.65 ± 0.77, P 〈 0.05 for E. faecalis）. The four strains of probiotics decreased the MP activity and the IL-1 expression, but increased the IL-4 expression. E. faecalis had a better effect on DSS-induced experimental colitis in mice than the other three strains. CONCLUSION： The four strains of probiotics have beneficial effects on experimental colitis in mice, E. faecalis has a better effect on DSS-induced experimental colitis in mice than the other three strains. Supplement of probiotics provides a new therapy for UC.     

Vanilloid receptor-1 containing primary sensory neurones mediate dextran sulphate sodium induced colitis in rats

BACKGROUND AND AIMS: The role of sensory neurones in colitis was studied by chemical denervation of primary sensory neurones as well as antagonism of the vanilloid receptor-1 (VR-1) in rats prior to administration of dextran sulphate sodium (DSS) to induce colitis. METHODS: Neonatal rats were chemically denervated by subcutaneous administration of capsaicin; controls received capsaicin vehicle only. When animals reached maturity, colitis was induced by administration of 5% DSS in drinking water for seven days. Additionally, normal adult rats were treated with a VR-1 antagonist capsazepine (CPZ) or vehicle twice daily via an enema from day 0 to day 6 of the DSS regimen. Control rats were treated with an enema infusion of vehicle and 5% DSS, or without either an enema infusion or DSS in drinking water. For both groups of rats, severity of inflammation was quantitated by disease activity index (DAI), myeloperoxidase (MPO) activity, and histological examination. RESULTS: DSS induced active colitis in all control rats with resultant epithelial ulceration, crypt shortening, and neutrophil infiltration. Both neonatal capsaicinised rats and normal adult rats treated with CPZ enemas exhibited significantly lower levels of DAI, MPO, and histological damage compared with vehicle treated rats (p< 0.05). CONCLUSIONS: Neonatal capsaicinisation and local administration of CPZ prevents intestinal inflammation in a well established model of colitis indicating that primary sensory neurones possessing VR-1 receptors are required in the propagation of colonic inflammation.     

Inhibition of neutrophil elastase prevents the development of murine dextran sulfate sodium-induced colitis

Background Neutrophil elastase (NE) is a major secretory product from activated neutrophils and a major contributor to tissue destruction. However, little is known about the pathogenic contribution of NE to ulcerative colitis (UC). This study was designed to investigate the contribution of NE by measuring NE activity in plasma and colonic mucosal tissue from UC patients and a murine acute colitis model, and to elucidate the therapeutic effect of the NE-specific inhibitor ONO-5046. Methods The NE enzyme activities in plasma and colonic mucosal tissue from UC patients were directly measured using an enzyme–substrate reaction. Acute colitis was induced in mice by administration of 1.5% dextran sulfate sodium (DSS) for 5 days. DSS-induced colitis mice were then treated with ONO-5046 (50 mg/kg body weight) intraperitoneally twice a day. Results In UC patients, the NE enzyme activity was significantly elevated in both the plasma and colonic mucosal tissue compared with healthy controls. In DSS-induced colitis mice, the NE enzyme activity increased in parallel with the disease development. ONO-5046 showed therapeutic effects in DSS-treated mice by significantly reducing weight loss and histological score. ONO-5046 suppressed the NE enzyme activities in both plasma and culture supernatant of colonic mucosa from DSS-induced colitis mice. Conclusions ONO-5046, a specific NE inhibitor, prevented the development of DSS-induced colitis in mice. NE therefore represents a promising target for the treatment of UC patients.     

Wuchereria bancrofti macrophage migration inhibitory factor-2 (rWbaMIF-2) ameliorates experimental colitis

Immunomodulatory molecules produced by helminth parasites are receiving much attention recently as novel therapeutic agents for inflammation and autoimmune diseases. In this study, we show that macrophage migration inhibitory factor (MIF) homologue from the filarial parasite, Wuchereria bancrofti (rWbaMIF-2), can suppress inflammation in a dextran sulphate sodium salt (DSS)-induced colitis model. The disease activity index (DAI) in DSS given mice showed loss of body weight and bloody diarrhoea. At autopsy, colon of these mice showed severe inflammation and reduced length. Administration of rWbaMIF-2 significantly reduced the DAI in DSS-induced colitis mice. rWbaMIF-2-treated mice had no blood in the stools, and their colon length was similar to the normal colon with minimal inflammation and histological changes. Pro-inflammatory cytokine genes (TNF-α, IL-6, IFN-γ, IL-1β, IL-17A and NOS2) were downregulated in the colon tissue and peritoneal macrophages of rWbaMIF-2-treated mice. However, there were significant increases in IL-10-producing Treg and B1 cells in the colon and peritoneal cavity of rWbaMIF-2-treated mice. These findings suggested that rWbaMIF-2 treatment significantly ameliorated the clinical symptoms, inflammation and colon pathology in DSS given mice. This immunomodulatory effect of rWbaMIF-2 appeared to be by promoting the infiltration of Treg cells into the colon.     

Geranylgeranylacetone protects mice from dextran sulfate sodium-induced colitis

Objective. Geranylgeranylacetone (GGA) has recently been reported to induce heat shock protein (HSP) 70, which has a protective function against inflammation. We investigated the therapeutic effects of oral administration of GGA on dextran sulfate sodium (DSS)-induced colitis in mice.Material and methods. BALB/c mice were given 3% DSS solution orally for 7?days to induce colitis. The disease activity of colitis was assessed clinically every day, and histology in the colon was evaluated at 7?days post-DSS. The levels of myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)-α and interferon (IFN)-γ in the colon tissues were also examined. In addition, expression of HSPs 25, 40, 70 and 90 in the colon tissue was determined by Western blot analysis. Mice were orally administered GGA (50–500?mg/kg) when treatment of DSS started.Results. It was found that GGA significantly reduced the clinical severity of colitis and suppressed the levels of MPO activity, TNF-α and IFN-γ induced by DSS in the colon. On the other hand, GGA enhanced the expression of HSP70 in the colon of mice given DSS. HSP70-positive cells were identified in the epithelial cells of the colon from mice treated with GGA and DSS.Conclusions. Taken together, these results suggest that GGA is a new anti-inflammatory drug that could be useful in the treatment of colitis such as inflammatory bowel disease.     

Kefir treatment ameliorates dextran sulfate sodium-induced colitis in rats

AIM: To investigate the preventive effect of kefir on colitis induced with dextran sulfate sodium(DSS) in rats.METHODS: Twenty-four male Wistar-albino rats were randomized into four groups: normal control,kefircontrol,colitis,and kefir-colitis groups. Rats in the normal and kefir-control groups were administered tap water as drinking water for 14 d. Rats in the colitis and kefir-colitis groups were administered a 3% DSS solution as drinking water for 8-14 d to induce colitis. Rats in the kefir-control and kefir-colitis groups were administered 5 m L kefir once a day for 14 d while rats in the normal control and colitis group were administered an identical volume of the placebo(skim milk) using an orogastric feeding tube. Clinical colitis was evaluated with reference to the disease activity index(DAI),based on daily weight loss,stool consistency,and presence of bleeding in feces. Rats were sacrificed on the 15 th day,blood specimens were collected,and colon tissues were rapidly removed. Levels of myeloperoxidase(MPO),tumor necrosisfactor(TNF)-α,interleukin(IL)-10,malondialdehyde,and inducible nitric oxide synthase(i NOS) were measured in colon tissue.RESULTS: The DAI was lower in the kefir-colitis group than in the colitis group(on the 3rd and 5th days of colitis induction; P 0.01). The DAI was also significantly higher in the colitis group between days 2 and 6 of colitis induction when compared to the normal control and kefir-control groups. The DAI was statistically higher only on the 6th day in the kefircolitis group when compared to that in the normal control groups. Increased colon weight and decreased colon length were observed in colitis-induced rats. Mean colon length in the colitis group was significantly shorter than that of the kefir-control group. Kefir treatment significantly decreased histologic colitis scores(P 0.05). MPO activity in the colitis group was significantly higher than in the kefir-control group(P 0.05). Kefir treatment significantly reduced the DSS colitis-induced TNF-α increase(P 0.01). No statistically significant differences were observed among groups for IL-10 and MDA levels. Colon tissue i NOS levels in the colitis group were significantly higher than those in the control and kefir-colitis groups(P 0.05).CONCLUSION: Kefir reduces the clinical DAI and histologic colitis scores in a DSS-induced colitis model,possibly via reduction of MPO,TNF-α,and i NOS levels.     

Pattern Recognition Scavenger Receptors, SR-A and CD36, Have an Additive Role in the Development of Colitis in Mice

The multifunctional pattern recognition scavenger receptors, SR-A and CD36, are predominantly expressed by lamina propria macrophages and considered important in innate immunity. We examined the role of these receptors in the pathophysiology of inflammatory bowel disease. Colitis was induced in wild type (WT), SR-A^−/−, CD36^−/−, and SR-A/CD36 double deficient mice by administering DSS. DSS-induced moderately severe colitis in WT mice was manifested by weight loss, reduced hematocrit, and pathology. SR-A/CD36 double deficient mice developed significantly more severe colitis as indicated by anemia (P < 0.01), decreased colonic length due to inflammation (P < 0.01), and lesions when compared with WT and single deficient animals. Serum amyloid A was significantly more elevated in SR-A/CD36^−/− mice (P < 0.01) compared with WT and single deficient animals. However, the spleens of WT mice (P < 0.05) were significantly enlarged. Inflammatory cytokine levels were considerably increased in WT mice (IL-6 P < 0.001, TNFα P < 0.01). In contrast, SR-A deficient mice maintained more normal body and splenic weight and developed less severe colonic lesions compared to other groups. In conclusion, our data indicate that SR-A/CD36 double deficiency leads to more severe colonic lesions and dysregulated inflammatory response as compared with single SR-A or CD36 deficiency in colitis, suggesting additive effects between these two receptors in this model.     

双歧杆菌对葡聚糖硫酸钠(DSS)诱导的小鼠结肠炎肠道黏膜的保护作用及其对NF-κB的影响

目的随着对炎症性肠病(inflammatory bowel disease,IBD)发病机制的深入研究,肠道微生态与免疫系统的密切关系日益受到重视。本研究旨在评价双歧杆菌单一活菌制剂对葡聚糖硫酸钠(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作用机制。方法 BALB/c小鼠饮用含7%DSS的饮用水10d,诱导小鼠亚急性结肠炎的模型,模拟人类溃疡性结肠炎。空白对照组(n=6)饮用未添加DSS的饮用水。饮用DSS的小鼠(n=37)随机分为5组,分别给予不同的药物治疗:①提前给予双歧杆菌治疗组(Pre-BIF):在小鼠暴露于DSS前10d及暴露过程中给予双歧杆菌治疗;②强的松治疗组(PRED):在小鼠暴露于DSS同时给予强的松治疗;③双歧杆菌治疗组(BIF):小鼠暴露于DSS的同时给予双歧杆菌治疗;④强的松+双歧杆菌联合治疗组(PRED+BIF):小鼠暴露于DSS的同时给予强的松和双歧杆菌联合治疗;⑤生理盐水对照组(NS):小鼠暴露于DSS的同时给予生理盐水作为对照。不同药物皆以溶液形式灌胃给药。从4方面评价各组的处理反应:①一般情况:包括体重、结肠长度、大体评分;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(MPO)活性;④免疫组织化学方法检测活化的NF-κB。结果 Pre-BIF治疗组和BIF治疗组的大体评分、组织病理评分、MPO活性与NS对照组相比明显改善(P0.01;P0.05)。Pre-BIF治疗组、BIF治疗组和PRED+BIF治疗组的NF-κB活性评分显著低于NS对照组(P均0.01)。结论双歧杆菌对小鼠DSS结肠炎肠道黏膜具有保护作用,提前应用保护效果更好。双歧杆菌对肠道黏膜的保护作用与抑制NF-κB的活化有关。     

Preventive efficacy of butyrate enemas and oral administration of Clostridium butyricum M588 in dextran sodium sulfate-induced colitis in rats

Butyrate enemas have been reported to be effective in ulcerative colitis. However, long-term use is difficult because of the troublesome procedure and the unpleasant smell. We therefore investigated the effects of the oral administration of Clostridium butyricum M588 (CBM588), an enterobacterium producing butyrate, in dextran sodium sulfate (DSS)-induced colitis in rats. First, we confirmed the effects of pre-treatment with a butyrate enema on DSS colitis. We then studied the efficacy of oral administration of CBM588 which was started 1 week prior to the induction of DSS colitis. In the CBM588 group, the ulcer index and myeloperoxidase (MPO) activity in the distal colon were significantly lower than in the control group. Proliferating cell nuclear antigen (PCNA) immuno-positive cells were increased around the ulcer in the CBM588 group. In regard to the contents of the cecum and colon, the proportions of Lactobacillus and Eubacterium were increased in the cecum in the CBM588 group. Further, there were significant increases of n-butyrate, propionate, and acetate concentrations in the cecum in the CBM588 group. These results indicated that the oral administration of CBM588 alleviated DSS-induced colitis, and may be useful instead of butyrate enema. Received: August 10, 1999 / Accepted: November 26, 1999     

PPARβ/δ Protects Against Experimental Colitis Through a Ligand-Independent Mechanism

Peroxisome proliferator-activated receptors (PPARs) β/δ and γ have overlapping roles in the negative regulation of inflammatory response genes. Ligand activation of PPARγ protects against experimental colitis in mice. PPARβ/δ can negatively regulate inflammation and is highly expressed in the epithelial cells of the colon, therefore PPARβ/δ may also have a role in experimental colitis. In these studies, colitis was induced by dextran sodium sulfate (DSS) treatment in wild-type and PPARβ/δ-null mice, with and without the PPARβ/δ specific ligand GW0742. PPARβ/δ-null mice exhibited increased sensitivity to DSS-induced colitis, as shown by marked differences in body weight loss, colon length, colonic morphology, myeloperoxidase activity and increased expression of mRNAs encoding the inflammatory markers interferon γ, tumor necrosis factor-α, and interleukin-6 compared to similarly treated wild-type mice. Interestingly, these differences were not affected by ligand activation of PPARβ/δ in either genotype. These studies demonstrate that PPARβ/δ expression in the colonic epithelium inhibits inflammation and protects against DSS-induced colitis through a ligand-independent mechanism.     

Carbon Monoxide Liberated from Carbon Monoxide-Releasing Molecule Exerts an Anti-inflammatory Effect on Dextran Sulfate Sodium-Induced Colitis in Mice

Background

Endogenous carbon monoxide (CO) is one of the three products of heme degradation by heme oxygenase-1 (HO-1) and exerts novel anti-inflammatory and anti-apoptotic effects as a gaseous second messenger. The purpose of this investigation was to determine whether exogenous CO could modulate intestinal inflammation.

Methods

Acute colitis was induced with 2% DSS in male C57BL/6 mice. CO-releasing molecule-2 (CORM-2; tricarbonyldichlororuthenium(II) dimer) was intraperitoneally administered twice daily and the disease activity index (DAI) was determined. We measured tissue-associated myeloperoxidase (MPO) activity as an index of neutrophil infiltration, and the production of keratinocyte chemoattractant (KC) and tumor necrosis factor-?? (TNF-??) protein in the intestinal mucosa. In an in-vitro study, young adult mouse colonic epithelial (YAMC) cells were incubated with TNF-??, and KC mRNA/protein expression and nuclear translocation of nuclear factor-kappa B (NF-??B) were measured with or without CORM-2 treatment.

Results

After DSS administration, DAI score increased in a time-dependent manner, and this increase was ameliorated by CORM-2 treatment. Increases in MPO activity and in the production of KC and TNF-?? after DSS administration were significantly inhibited by CORM-2. TNF-??-induced KC production in YAMC cells was also inhibited by CORM-2 treatment. Further, nuclear translocation of NF-??B in YAMC cells was inhibited by CORM-2.

Conclusion

CORM-liberated CO significantly inhibited inflammatory response in murine colitis by inhibition of cytokine production in the colonic epithelium. These results suggest that CO could become a new therapeutic molecule for inflammatory bowel disease.     

Protective Effect of Lafutidine, a Novel Histamine H2-Receptor Antagonist, on Dextran Sulfate Sodium-Induced Colonic Inflammation Through Capsaicin-Sensitive Afferent Neurons in Rats

Lafutidine, a histamine H2-receptor antagonist, exhibits gastric mucosal protective action mediated by capsaicin-sensitive afferent neurons, in addition to a potent antisecretory effect. In this study we examined the effect of lafutidine on dextran sulfate Na (DSS)-induced ulcerative colitis in rats, in relation to capsaicin-sensitive afferent neurons. Experimental colitis was induced in rats by daily treatment with 3% DSS in drinking water for 7 days. Lafutidine, capsaicin, and cimetidine were administered per os twice daily for 6 days. The ulceration area, colon length, and myeloperoxidase (MPO) activity were measured on day 7 after the onset of DSS treatment. DSS caused severe mucosal lesions in the colon, accompanied by an increase in MPO activity as well as a decrease in body weight gain and colon length. Daily administration of lafutidine dose-dependently reduced the severity of DSS-induced colitis and significantly mitigated changes in the colon length and MPO activity. The effects of lafutidine were mimicked by daily administration of capsaicin but not cimetidine and were totally abolished by chemical ablation of capsaicin-sensitive afferent neurons. In contrast, desensitization of afferent neurons significantly worsened the colonic inflammation induced by DSS. It was also found that both lafutidine and capsaicin increased the secretion of mucus in the colonic mucosa. These results suggest that lafutidine is effective against the ulcerative colitis induced by DSS through capsaicin-sensitive afferent neurons. This action might be attributable at least partly to the enhancement of colonic mucus secretion.     

氧化苦参碱对葡聚糖硫酸钠诱导结肠炎影响的初步研究

目的探讨氧化苦参碱(OM)对大鼠溃疡性结肠炎(UC)的保护作用.方法用葡聚糖硫酸钠(DSS)诱导大鼠结肠炎,对比OM组、DSS对照组和正常对照组的疾病活动度(DAI)及病理学评分.结果两项指标在3组间均存在显著差异(P＜0.05).结论OM能够减轻DSS诱导的结肠炎症状和肠粘膜损害.