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1.
A number of rodent models for inflammatory bowel disease (IBD) have been developed, but most cannot be used to develop and validate new therapies for IBD. From the models developed, the IL-10 deficient mouse model is the one that results in a disease similar to human IBD; however, in this model, colitis occurs with variable incidence taking 3-4 months to develop. These are serious problems with the model when evaluating a new therapy because of the large-scale experiments required and the difficulty in performing an accurate pharmacological analysis. In this study, the IL-10 deficient mouse model was modified by transferring whole spleen and mesenteric lymph node cells from IL-10 deficient mice to CB-17 SCID mice. In this IL-10 deficient cell transfer model, chronic intestinal inflammation developed in all recipients within 2-3 weeks, which was far earlier than in donor IL-10 deficient mice. The pathological phenotypes were similar to those of IL-10 deficient mice and CD45RBhi T cell-transfer models. In addition, we assessed several agents for inflammatory bowel disease to validate the general utility of this cell transfer model. It is worth noting that TNFR-Ig or prednisolone, which is effective for treatment of patients with severe-fulminant Crohn's disease, markedly attenuated pathological clinical indices in this colitis model, whereas the immunosuppressive agents, azathioprine, tacrolimus, and cyclosporine A produced no significant effect. These results suggest that the IL-10 deficient cell transfer model is a good experimental model to use for developing new and effective therapies for active IBD.  相似文献   

2.
There is a great need for new intervention and prevention strategies against Crohn's disease (CD), a chronic, relapsing tissue-destructive inflammatory bowel disease (IBD). Estimates indicate more than 1 million cases of IBD in the United States occur annually, with 50% involving CD. The clinical features of CD correlate with certain mouse models of colitis, including the spontaneous colitis observed in interleukin-10 deficient (IL-10(-/-)), senescence accelerated mice (SAMP1/Yit) and trinitrobenzene sulfonic acid (TNBS)-treated mice. Chemokines undoubtedly play a pivotal role in the regulation (i.e., initiation, maintenance, and suppression) of mucosal inflammation and tissue destruction. A number of key advances have led to greater understanding of the steps responsible for colitis and the roles played by chemokines. In fact, CXCR3 and the ligands for this chemokine receptor, monokine-induced by interferon-gamma (IFN-gamma) (MIG/CXCL9), IFN-gamma-inducible 10 kDa protein (IP-10/CXCL10), and IFN-gamma-inducible T cell alpha-chemoattractant (I-TAC/CXCL11) are differentially expressed at sites of colitis in IL-10(-/-) mice and in clinical cases of CD. While we have demonstrated that antibodies directed against CXCL10 could both prevent the onset and cure of pre-existing colitis in IL-10(-/-) mice, studies by other investigators have shown the efficacy of CXCR3 blockade to mitigate colitis and other inflammatory diseases. This review describes the hallmarks of IBD, CXCL9-11, and CXCR3 expression during murine colitis and IBD, gives an overview of the antagonist therapies targeting the CXCR3 axis, details current and pending bio-therapies for IBD, and discusses what is known about the cellular and CXCR3-mediated mechanisms of colitis.  相似文献   

3.
4.
Inflammatory bowel disease (IBD) is characterized by repeated chronic inflammation of the gastrointestinal tract. We have used the complementary model of colonic inflammation to examine the roles of peroxisome proliferator-activated receptor α (PPARα) in colonic inflammation and thus its possible role in IBD. We characterized an innate immune-mediated model of colitis induced by dextran sulfate sodium (DSS). Mice with DSS-induced colitis were injected with Wy-14643 (2 mg/kg) as a PPARα agonist every day from day 0 to day 5. We show that mice given Wy-14643 were less susceptible to experimental acute colitis induced by DSS, and this decreased susceptibility was correlated with decreased production of IFNγ, IL-1β, IL-6, and TNF-α. Our findings suggest that PPARα has a role in controlling colonic inflammation and mucosal tissue homeostasis.  相似文献   

5.
AMP-activated protein kinase (AMPK), a cellular energy sensor, has been reported to participate in modulating inflammatory responses, but its role in intestinal inflammation remains unclear. IBD has been characterized by excessive innate and adaptive immune responses. Here, the roles of 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), an agonist of AMPK, in regulating immune responses of experimental colitis were investigated. In vitro effects of AICAR on LPS-induced macrophage activation and Th1 and Th17 differentiation, as well as in vivo effects of AICAR in mice with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis, were explored. In acute colitis, daily AICAR treatment commenced 2 days after TNBS delivery (day 1), while in relapsing colitis, AICAR treatment commenced after three weekly TNBS administrations. Colon inflammation, production of proinflammatory cytokines and NF-κB activation in colon tissues, and Th1 and Th17 cell populations in lamina propria mononuclear cells (LPMCs) and mesenteric lymph node cells (MLNs) were assayed. Results show that AICAR significantly inhibited in vitro LPS-induced macrophage activation and Th1 and Th17 cell differentiation. Administration of AICAR was therapeutically effective in ameliorating acute and relapsing experimental colitis, as shown by reduced body weight loss and significant attenuation in colon histological inflammation. Moreover, this treatment inhibited NF-κB activation in macrophages, and reduced levels of TNF, Th1- and Th17-type cytokines, and Th1 and Th17 cell populations in LPMCs and MLNs. AICAR-initiated AMPK activation may act as a central downregulator in ongoing innate and adaptive immune responses of murine colitis, providing a novel therapeutic approach in the treatment of IBD.  相似文献   

6.
目的:研究沙利度胺乳膏对小鼠皮炎湿疹模型的治疗作用及抗炎机制。方法:60只小鼠被随机分为正常对照组,模型对照组,沙利度胺乳膏低、中、高浓度组和阳性(氢化可的松)对照组(每组10只)。采用二硝基氯苯(DNCB)诱导小鼠慢性皮炎湿疹模型。正常对照组和模型对照组给予空白基质,其他用药组外用给药,1 d 2次,连续15 d。千分尺测量小鼠左右耳中部厚度,计算左右耳厚度差;电子天平称量左右耳片质量,计算左右耳质量差;HE染色观察小鼠耳组织病理学变化,并进行病理组织学评分;ELISA法测定小鼠血清中TNF-α、IL-2、IL-4、IL-12、IL-18的含量。结果:沙利度胺乳膏能减轻小鼠耳厚度,减轻耳部炎症程度,升高其降低的IL-2、IL-4、IL-18水平,降低其升高的TNF-α、IL-12水平,并呈现良好的量效关系。结论:沙利度胺乳膏对皮炎湿疹有较好的治疗作用,其作用机制可能与调节Th1和Th2平衡有关。沙利度胺乳膏有望开发成一种治疗慢性皮炎湿疹的新药。  相似文献   

7.
目的探讨白介素-18(IL-18)影响肝癌裸鼠皮下移植瘤浸润的T细胞子集变化的机制。方法以HepG2细胞在裸鼠皮下接种,形成人肝癌皮下移植瘤的同时,以不同剂量IL-18分为4组治疗,4组分别腹腔注射IL-18 0.75,1.00,1.25,0(模型组)μg(0.1 mL)/只,治疗4周,另设正常对照组。观察肿瘤的生长速度和瘤体大小的变化。4周后处死取肿瘤组织和脾组织,免疫磁珠阴选组织中CD4+T细胞,流式细胞术检测各组肿瘤组织及脾组织中IL-17+/IFN-γ-CD4+T(Th17细胞)、IL-17-/IFN-γ+CD4+T(Th1)和IL-17+/IFN-γ+CD4+T细胞的变化。结果 HepG2细胞株建立了裸鼠肝癌皮下移植瘤模型,IL-18抑制人肝癌皮下移植瘤的形成及转移,治疗时间越长剂量越大,抑制效果越明显;与正常对照组比较,肿瘤组织中Th17和IL-17+/IFN-γ+CD4+T细胞浸润数目增加,Th1细胞降低,与脾组织中一致,与正常对照组比较有显著差异(P<0.05)。给IL-18后,随着剂量的增加,Th1细胞增加,IL-17+/IFN-γ+CD4+T细胞和Th17细胞浸润数目降低,给药组与模型组比较有显著差异(P<0.05或0.01)。结论 IL-17+/IFN-γ+CD4+T细胞数目在裸鼠移植瘤及其脾组织中增加,可能是在肿瘤环境中,促进其向Th17细胞分化;IL-18通过诱导IFN-γ的生成促进Th1细胞的生成,呈正反馈效应抑制肿瘤的增殖和转移。  相似文献   

8.
1 A novel animal model of spontaneous colonic inflammation, the multiple drug-resistant (mdr1) a(-/-) mouse, was identified by Panwala and colleagues in 1998. The aim of our study was to further characterise this model, specifically by measuring cytokines that have been implicated in inflammatory bowel disease (IBD) (IL-8 and IFN-gamma) in the colon/rectum of mdr1a(-/-) mice, and by determining the sensitivity of these, together with the macroscopic, microscopic and disease signs of colitis, to dexamethasone (0.05, 0.3 and 2 mg kg(-1) subcutaneously (s.c.) daily for 7 days). 2 All mdr1a(-/-) mice had microscopic evidence of inflammation in the caecum and colon/rectum, while control mice with the same genetic background did not. Significant increases in colon/rectum and caecal weights and also in cytokine levels (both IFN-gamma and IL-8) in homogenised colon/rectum were observed in mdr1a(-/-) mice compared to mdr1a(+/+) mice. 3 Dexamethasone reduced the increases in tissue weights and also microscopic grading of colitis severity, but had no effect on IFN-gamma or IL-8. 4 This study supports the similarity of the gastrointestinal inflammation present in mdr1a(-/-) mice to that of human IBD, in particular Crohn's disease. This has been demonstrated at the macroscopic and microscopic levels, and was supported further by elevations in colonic levels of IFN-gamma and IL-8 and the disease signs observed. The incidence of colitis was much higher than previously reported, with all mice having microscopic evidence of colitis. The limited variance between animals in the parameters measured suggests that this model is reproducible.  相似文献   

9.
Inflammatory bowel disease (IBD) is a chronic and recurrent intestinal inflammatory disease with high risks for colorectal cancer and extremely affect people's health. Secoisolariciresinol diglucoside (SDG), a major component of lignans, exerts anti-inflammatory effects against digestive system diseases through a multi-target mechanism. However, the effect of SDG on IBD is not clear. In the present study, we aimed to investigate the effects of SDG on IBD and elucidate the underlying mechanism. The Dextran Sulfate Sodium Salt (DSS)-induced colitis model and lipopolysaccharide (LPS) stimulated RAW264.7 mouse macrophages cellular inflammation model were established. Morphological and pathological changes in colitis tissue in mice were observed by HE staining. Macrophage infiltration was detected by flow cytometry. The levels of nucleotide oligomerization domain-like receptor protein 1 (NLRP1) inflammasome complexes, nuclear factor-kappa B (NF-κB) and inflammatory cytokines were determined using quantitative real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The results showed that SDG significantly attenuated the pathological severity and the number of macrophage infiltration of colitis in mice. Besides, SDG decreased the levels of inflammatory cytokines (IL-1β, IL-18 and TNF-α) and inhibited the activation of the NLRP1 inflammasome in DSS-induced colitis mice and RAW264.7 mouse macrophages. Moreover, the inhibitory effect of SDG was partly dependent on the disruption of NF-κB activation. Our results indicated that SDG relieves colitis by inhibiting NLRP1 inflammasome, and partly dependent on the disruption of NF-κB activation. Therefore, SDG may be a potential treatment option for IBD.  相似文献   

10.
BackgroundInterleukin-10-deficient (IL-10 (−/−)) mice spontaneously develop chronic colitis and adenocarcinoma through the dysplasia sequence. Autophagy malfunction is associated to inflammatory bowel disease (IBD) and colorectal cancer (CRC) pathogenesis. Autophagy is regulated by silent information regulator-1 (SIRT1), a NAD +-dependent histone deacetylase. Our aim was to investigate the expression changes of SIRT1-AMPK-autophagy pathway in the progression from chronic colitis to CRC.MethodsWe studied C57BL/6-IL-10-deficient mice between 6 and 18 weeks of age. Macroscopic and histological analysis, and characterization of inflammatory and tumor biomarkers were performed.ResultsIL-10-deficient mice developed colitis from the age of 6 weeks onward. The severity of inflammation and dysplasia, and the proliferative activity increased gradually with age. IL-10 (−/−) mice were characterized by improved levels of TNF-α and decreased expression of SIRT1. Moreover, our findings show an increase in p-AMPK expression and an activation of the autophagy in IL-10 (−/−) mice from all stages, evidenced by the accumulation of LC3-II protein, the increase in Beclin 1 expression and the reduction in Bcl-2 levels.ConclusionsSIRT1-AMPK-autophagy pathway may be involved in the maintenance of chronic inflammation and dysplasia development in the IL-10-deficient mice model. Modulation of this pathway could be a novel strategy for IBD and CRC treatment.  相似文献   

11.
Crohn's disease (CD) and ulcerative colitis (UC) are the major forms of inflammatory bowel diseases (IBD) in man. They are caused by damage to the lining of the intestine and deeper layers, due to an excessive immune response directed against components of the gut microflora and poorly controlled by counter-regulatory mechanisms. CD and UC are however immunologically distinct. CD-related inflammation is characterized by a marked mucosal infiltration of T lymphocytes secreting T helper type (Th) 1 and Th17 cytokines. In UC, the local immune response is less polarized but may show enhanced production of IL-5, IL-13 and Th17 cytokines. Downstream however CD and UC share important end-stage effector pathways of intestinal injury, mediated by an active cross-talk between immune and non-immune cells. The clarification of the complex networks of immune-inflammatory mediators operating in the gut of IBD patients has led to the identification of new targets that should facilitate the development of novel biological therapies.  相似文献   

12.
Non-alcoholic fatty liver (NAFLD) is accompanied by an increased expression of oxidative stress parameters, in addition to the inflammatory cytokines; tumor necrosis factor alpha (TNF-α), interleukin type 1beta (IL-1β), and interleukin type 18 (IL-18). The aim of this study is to investigate the effect of dapagliflizon (DAPA) on high carbohydrate-high fat (HCHF) diet-induced expression of inflammatory cytokines in rat liver. NAFLD was induced by feeding the rats HCHF diet (consist of animal fat tallow and standard show pellets) and the consumption of fructose in drinking water (10%) for 12 or 18 weeks. The oral administration of DAPA (1 mg/kg/day) from 13th week to 18th week significantly improved NAFLD as indicated by a significant reduction in liver aminotransferases in addition to a significant decrease of serum MDA, cholesterol, triglyceride and LDL-cholesterol with concomitant significant elevation of HDL-cholesterol. DAPA-treated animals showed a significant reduction of liver homogenate content of TNF-α, IL-1β, and IL-18. These results indicate that the administration of DAPA may be beneficial against HCHF diet-induced NAFLD. Histopathological examination of liver specimens supported the conclusion that DAPA improves steatohepatitis induced by HCHF diet.  相似文献   

13.
In both Crohn's disease (CD) and ulcerative colitis (UC), the major forms of inflammatory bowel diseases (IBD) in humans, the pathologic process consists of an aberrant local immune response to components of the bacterial microflora, due to abnormally strong effector cell activity that is poorly controlled by counter-regulatory mechanisms. There is also evidence that mucosal immune cells actively interact with non-immune cells to promote tissue damage, and that cytokines are essential mediators of this cross-talk. Interleukin-21 (IL-21), the latest member of the common gamma-chain-dependent cytokine family, is a product of activated CD4+ T cells and natural killer T cells. IL-21 is produced in excess in CD tissue, where it helps sustain the ongoing Th1 inflammation. High IL-21 production occurs also in the inflamed colon of most patients with UC, a disease that is not associated with a marked Th1 cell response. This suggests that, in the gut, IL-21 can modulate additional inflammatory pathways other than enhancing Th1 cell immunity. Indeed, IL-21 stimulates the secretion of extracellular matrix degrading enzymes by fibroblasts, and of the T cell chemoattractant, MIP-3 alpha, by epithelial cells. These data collectively indicate that IL-21 is a mediator of the chronic inflammatory response in CD and UC, and suggest that IL-21 may be an emerging therapeutic target in IBD.  相似文献   

14.
Ulcerative colitis (UC) and Crohn's disease are inflammatory disorders of unknown cause and difficult to treat, though some synthetic chemicals, including ligands for peroxisome proliferator-activated receptors (PPARs), are anticipated to be useful drugs. In contrast, few food phytochemicals have been reported to suppress colitis in animal models. The present study was undertaken to explore the suppressive efficacy of zerumbone (ZER), a sesquiterpenoid present in the rhizome of Zingiber zerumbet Smith that is used as a condiment in Southeast Asian countries and known to be a potent suppressant of cyclooxygenase (COX)-2 and inducible nitric oxide synthase expression in cell culture systems. Acute colitis was induced by exposing female ICR mice to 5% DSS in drinking water for 1 week. One week prior to DSS administration, the experimental mice were fed ZER alone, nimesulide (NIM, a selective COX-2 inhibitor) alone, or both in combination (1000 ppm each) for a total of 2 weeks. Inflammatory biomarkers, i.e. interleukin (IL)-1alpha and IL-1beta, tumor necrosis factor (TNF)-alpha, and prostaglandin (PG)E(2) and PGF(2alpha) in colonic mucosa were quantified by an enzyme-linked immunosorbent assay in conjunction with histological alterations. Oral feeding of ZER significantly lowered the levels of IL-1beta [inhibitory rate (IR)=34%], TNF-alpha (IR=29%), and PGE(2) (IR=73%) and suppressed DSS-induced colitis, whereas NIM suppressed the histological changes induced by DSS without affecting inflammatory biomarkers. However, their treatment in combination was most effective for suppressing these biomarkers. Our results suggest that ZER is a novel food factor for mitigating experimental UC and that use of a combination of agents, with different modes of actions, may be an effective anti-inflammatory strategy.  相似文献   

15.
Metabolic diseases are associated with activation of the innate immune system in various tissues and characterized by elevated inflammatory factors and the presence of immune cells. Type 2 diabetes develops when islet beta cells are deficient in producing sufficient insulin to overcome peripheral insulin resistance. Intra-islet IL-1β activity diminishes beta cell function and survival and governs islet inflammation. Targeting the IL-1 system with the IL-1 receptor antagonist IL1Ra improved insulin secretion, glycaemia and reduced systemic inflammation in a proof of concept study with patients with type 2 diabetes. Currently, long lasting and specific IL-1β blocking antibodies are being evaluated in clinical trials and this may lead to a novel cytokine-based treatment for type 2 diabetes.  相似文献   

16.
AIM: To investigate the therapeutic effects of curcumin (Cur) on trinitrobenzene sulphonic acid (TNBS)-induced colitis and the effects of Cur on the balance of Th1/Th2 cytokines. METHODS: Colitis was induced by TNBS and treated with Cur (30 mg/kg/d, ip), dexamethasone (Dex, 2 mg/kg/d), or Cur plus dexamethasone (Cur+Dex, 30 mg/kg/d Cur ip+2 mg/kg/d Dex,ip). mRNA in colon mucosa were detected by real-time quantitative polymerase chain reaction. Intracellular cytokines were detected by flow cytometry and concentrations of cytokines in sera were detected by enzyme-linked immunosorbent analysis. RESULTS: Both Cur and Dex improved body weight loss, ameliorated histological images and decreased macroscopic score and myeloperoxidase activity. Cur decreased the expression of Th1 cytokines (IL-12, IFN-gamma, TNF-alpha, IL-1) and increased the expression of Th2 cytokines (IL-4 and IL-10) in colon mucosa. Cur also increased the proportion of IFN-gamma/IL-4 in splenocytes and circulation. Dex and Cur+Dex decreased the expression of Th1 cytokines but could not increase the expression of Th2 cytokines and the proportion of IFN-gamma/IL-4. CONCLUSION: Cur exerted therapeutic effects on colitis by regulating the shift from Th1 to Th2.  相似文献   

17.
Ulcerative colitis is an autoimmune-inflammatory disease characterized by abnormally increased expression of Toll-like receptor-4 (TLR4) in colonic epithelial cells, increased production of pro-inflammatory cytokines (e.g., TNF-α, IL-1β, IL-6, IL-12), chemokines (e.g., IP-10), and endothelial cell adhesion molecules (e.g., VCAM-1), plus enhanced leukocyte infiltration into colonic interstitium. Previously, we have shown that phenyl methimazole (C10) markedly decreases virally-induced TLR-3 expression and signaling and potently inhibits both TNF-α-induced VCAM-1 expression and the resultant leukocyte-endothelial cell adhesion. In this study we probed the hypothesis that C10 is efficacious in a TLR-4- and VCAM-1-associated murine model [the dextran sulfate sodium (DSS) model] of human colitis. C10 was administered intraperitoneally coincident with or after DSS treatment was initiated. Macroscopic colon observations revealed that C10 significantly reversed DSS-induced shortening of the colon (P < 0.05) and reduced the presence of blood in the colon. Histological analyses of colonic tissues revealed that C10 distinctly attenuated both DSS-induced edema as well as leukocyte infiltration in the colonic mucosa and resulted in pronounced protection against DSS-induced crypt damage (P < 0.001). Northern blot analyses and immunohistochemistry of colonic tissue revealed that C10 markedly diminished DSS-induced expression of pertinent inflammatory mediators: TNF-α, IL-1β, IL-6, IL-12, IP-10, TLR-4 and VCAM-1. Most importantly, C10 significantly improved survival and protected mice against DSS-induced colitic-death: 75% by comparison to 12.5% with identical treatment with DMSO-control (log rank test: P = 0.005). These results provide direct evidence that C10 suppresses DSS-induced colitis by inhibiting expression of key inflammatory mediators and leukocyte infiltration, and is a potentially attractive therapeutic for colitis.  相似文献   

18.
19.
Peroxisome proliferator-activated receptor gamma (PPARγ) was identified as a cell-intrinsic regulator of Th17 cell differentiation. Th17 cells have been associated with several autoimmune diseases, including experimental autoimmune encephalomyelitis (EAE), inflammatory bowel disease (IBD), and collagen-induced arthritis. In this study, we confirmed PPARγ-mediated inhibition of Th17 cell differentiation and cytokine production at an early stage. Treatment with ciglitazone, a PPARγ ligand, reduced both IL-1β-mediated enhancement of Th17 differentiation and activation of Th17 cells after polarization. For Th17 cell differentiation, we found that ciglitazone-treated cells had a relatively low proliferative activity and produced a lower amount of cytokines, regardless of the presence of IL-1β. The inhibitory activity of ciglitazone might be due to decrease of CCNB1 expression, which regulates the cell cycle in T cells. Hence, we postulate that a pharmaceutical PPARγ activator might be a potent candidate for treatment of Th17-mediated autoimmune disease patients.  相似文献   

20.
Inflammatory bowel diseases (IBD) are chronic inflammatory and relapsing diseases of the gut that may manifest as either Crohn's disease (CD) or ulcerative colitis (UC). CD and UC are immunologically different diseases characterized by exacerbated Th1 and Th2 response. T-cell resistance against apoptosis contributes to inappropriate T-cell accumulation and the perpetuation of chronic mucosal inflammation. In the present study we have investigated the effect exerted by guggulsterone (GS) a plant derived steroid isolated from the gum resin of the Commiphora mukul tree, in two models of intestinal inflammation induced in mice by trinitro-benzene sulfonic acid (TNBS) and oxazolone. We provided evidence that E-GS protects mice against development of sign and symptoms of colon inflammation. E-GS effectively attenuated the severity of wasting disease and the fecal score and colon inflammation as assessed by measuring the macroscopic- and microscopic-damage scores. Administration Z-GS failed to ameliorate colon inflammation in TNBS-induced colitis and had a partial effect in oxazolone-induced colitis. In vitro, mechanistic studies carried out using CD4+ cells isolated from the intestinal lamina propria demonstrate that GS effectively regulates the function of effector T cells by modulating cell signaling activation pathway caused by CD3/CD28. The net biological effects resulting from exposure to GS includes attenuation of generation of interleukin-2 and -4 and interferon-γ as well as T cell proliferation. In conclusion, GS is an anti-inflammatory compound with the capacity to prevent and ameliorate T-cell-induced colitis. These data ground the use of GS, a natural cholesterol-lowering agent, in the treatment of chronic inflammatory diseases.  相似文献   

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