The Effect of Glutamine on Pancreatic Damage in TNBS-Induced Colitis

Ulcerative colitis is a multifactorial inflammatory disease of the colon and rectum with an unknown etiology. The present study was undertaken to investigate the effect of glutamine administration on oxidative damage and apoptosis in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Rats received 1 g/kg/day glutamine for intragastric gavage for 7 days before TNBS solution administration and 3 days following TNBS solution administration until sacrifice. Then colonic and pancreatic malondialdehyde (MDA) and glutathione (GSH) levels, and colonic caspase-3 activities of the sacrified rats were measured. TNBS-induced colitis caused significantly increased in the caspase-3 activity and colonic and pancreatic MDA levels and decreased colonic and pancreatic GSH levels compared to those in the sham group. Glutamine treatment was associated with decreased MDA levels and caspase-3 activity and increased GSH levels in the colinic and pancreatic tissue. Histopathological examination revealed that the colonic mucosal structure was preserved and pancreatic inflammation decreased in the glutamine-treated group. In conclusion, glutamine appears to have protective effects against TNBS-induced colonic and pancreatic damage. These results imply a reduction in mucosal damage due to anti-inflammatory and antiapoptotic effects of glutamine.     

Effect of heme oxygenase-1 induction by octreotide on TNBS-induced colitis

BACKGROUND AND AIM: Ulcerative colitis is a chronic inflammatory disease of the colon and rectum. Although the precise etiology of ulcerative colitis remains unknown, it is believed to involve an abnormal host response to endogenous or environmental antigens, genetic factors, and oxidative damage. The aim of the present study was to investigate whether heme oxygenase-1 (HO-1) induction by octreotide could protect against oxidative and inflammatory damage from induced colitis. METHODS: Rats received octreotide 50 microg/kg per day intraperitoneally for 5 days before 2,4,6 trinitrobenzene sulfonic acid (TNBS) solution administration and for 15 days following TNBS solution administration. Rats were killed on day 21, and colonic malondialdehyde (MDA) levels, glutathione (GSH) levels and HO-1 expression were measured. Nuclear factor (NF)-kappaB and HO-1 expression was evaluated by immunohistochemical examination of the colonic tissue. RESULTS: Rats with TNBS-induced colitis had significantly increased colonic MDA levels and HO-1 expression in comparison to the control group. Octreotide treatment was associated with increased HO-1 expression and GSH levels, but decreased MDA levels. Histopathological examination revealed that the intestinal mucosal structure was preserved in the octreotide-treated group. In addition, treatment with octreotide significantly increased HO-1 expression and decreased NF-kappaB expression by immunohistochemistry when compared to the TNBS-induced colitis group. CONCLUSION: Octreotide appears to have protective effects against colonic damage in TNBS-induced colitis. This protective effect is, in part, mediated by modification of the inflammatory response and the induction of HO-1 expression.     

The Effect of Melatonin on TNBS-Induced Colitis

Ulcerative colitis is a multifactorial inflammatory disease of the colon and rectum with an unknown etiology. The present study was undertaken to investigate the effect of melatonin administration on oxidative damage and apoptosis in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Rats were divided into four groups as follows: Group 1 (n=8)—TNBS colitis; Group 2 (n=8)—melatonin, 10 mg/kg/day ip, for 15 days in addition to TNBS; Group 3 (n=8)—melatonin alone, 10 mg/kg/day ip, for 15 days; and Group 4 (n=8)—isotonic saline solution, 1ml/rat ip, for 15 days (sham control group). Colonic myeloperoxidase (MPO) activities, malondialdehyde (MDA) levels, and glutathione (GSH) levels are indicators of oxidative damage, while caspase-3 activities reveal the degree of apoptosis of the colonic tissue. In all TNBS-treated rats, colonic MPO activity and MDA levels were found to be increased significantly compared to those in the sham group. Colonic MPO activity and MDA levels were significantly lower in the melatonin treatment group compared to TNBS-treated rats. GSH levels of colonic tissues were found to be significantly lower in TNBS-treated rats compared to the sham group. Treatment with melatonin significantly increased GSH levels compared to those in TNBS-treated rats. Caspas-3 activity of colonic tissues was found to be significantly higher in TNBS-treated rats compared to the sham group. Treatment with melatonin significantly decreased caspase-3 activity compared to that in TNBS-treated rats. These results imply a reduction in mucosal damage due to anti-inflammatory and anti-apoptotic effects of melatonin.     

白细胞介素-23/-17轴在小鼠急性实验性结肠炎中的表达及作用

目的 研究白细胞介素(IL)-23/IL-17轴在小鼠实验性结肠炎结肠组织中的表达和作用.方法 将64只小鼠分为对照组24只、模型组24只、抗体组8只、正常血清组8只.除对照组外,其余各组建立小鼠急性实验性结肠炎模型.对照组和模型组小鼠分别于造模后24 h、48 h、7 d处死.抗体组和正常血清组小鼠分别于造模前2 h腹腔内注射多克隆大鼠抗小鼠IL-17中和抗体和正常大鼠血清,于造模48 h后处死.检测各组小鼠组织学损伤评分、肠组织髓过氧化物酶(MPO)活性;酶联免疫吸附试验检测结肠组织IL-23p19、IL-17含量;免疫组化染色检测核因子(NF)-κB p65在结肠组织中的表达;实时荧光定量(RT)PCR检测IL-23p19、IL-17、IL-12p35的mRNA表达水平.结果 模型组24 h、48 h、7 d时IL-23p19蛋白表达水平和mRNA表达水平[分别为(15.53±3.32)、(31.16±4.98)、(14.03±3.56)ng/mg蛋白和4.09±0.34、3.39±0.46、6.54±1.82]、IL-17的蛋白表达水平和mRNA表达水平[分别为(0.35±0.06)、(0.38±0.08)、(0.26±0.05)ng/mg蛋白和4.21±2.61、2.65±0.91、5.63±1.43]均显著高于正常对照组(P值均＜0.05),48 h时达高峰.IL-23与IL-17蛋白表达水平和mRNA表达水平呈正相关(r值分别为0.745和0.793,P＜0.05).抗体组IL-23p19和IL-12p35高水平表达,但NF-κB p65阳性细胞率、组织学评分及MPO活性[分别为1.86%±0.36%、0.63±0.52、(0.40±0.03)U/g]明显低于48 h模型组[分别为4.35%±0.37%、5.13±0.64、(2.29±0.40)U/g],说明中和IL-17后能明显减轻结肠炎症,抑制NF-κB活性.结论 IL-23/IL-17轴在急性实验性结肠炎早期阶段起关键作用.IL-17有望成为炎症性肠病治疗的新靶标.     

Oligosaccharides from agar inhibit murine intestinal inflammation through the induction of heme oxygenase-1 expression

Background

Agarose is hydrolyzed easily to yield oligosaccharides, designated as agaro-oligosaccharides (AGOs). Recently, it has been demonstrated that AGOs induce heme oxygenase-1 (HO-1) expression in macrophages and that they might lead to anti-inflammatory property. Nevertheless, the molecular mechanism of AGO-mediated HO-1 induction remains unknown, as does AGOs’ ability to elicit anti-inflammatory activity in vivo. This study was undertaken to uncover the mechanism of AGO-mediated HO-1 induction and to investigate the therapeutic effect of AGOs on intestinal inflammation.

Methods

Mice were treated with 2,4,6-trinitrobenzene sulfonic acid (TNBS) to induce colitis. The respective degrees of mucosal injury of mice that had received AGO and control mice were compared. We investigated HO-1 expression using Western blotting, quantitative real-time PCR (qRT-PCR), and immunohistochemistry. The expression of tumor necrosis factor-α (TNF-α) was measured using qRT-PCR and enzyme-linked immunosorbent assay.

Results

AGO administration induced HO-1 expression in colonic mucosa. The induction was observed mainly in F4/80 positive macrophages. Increased colonic damage and myeloperoxidase activity after TNBS treatment were inhibited by AGO administration. TNBS treatment induced TNF-α expression, and AGO administration suppressed induction. However, HO inhibitor canceled AGO-mediated amelioration of colitis. In RAW264 cells, AGOs enhanced HO-1 expression time-dependently and concentration-dependently and suppressed lipopolysaccharide-induced TNF-α expression. Furthermore, agarotetraose-mediated HO-1 induction required NF-E2-related factor 2 function and phosphorylation of c-jun N-terminal kinase.

Conclusions

We infer that AGO administration inhibits TNBS-induced colitis in mice through HO-1 induction in macrophages. Consequently, oral administration of AGOs might be an important therapeutic strategy for inflammatory bowel disease.     

徐长卿对三硝基苯磺酸诱导的大鼠结肠炎的作用

目的:探讨徐长卿对2,4,6-三硝基苯磺酸(trinitrobenzenesulfonic acid,TNBS)诱导的大鼠结肠炎的作用.方法:将40只♂SD大鼠随机分为4组:正常组、模型组、徐长卿组和巴柳氮组.除正常组外,其余3组大鼠均以TNBS灌肠造模.灌肠24h后,徐长卿组开始每天给予徐长卿4g/kg;巴柳氮组给予巴柳氮钠1g/kg灌胃治疗10d.每天观察大鼠一般情况,给药结束后,观察大鼠结肠大体损伤及病理,酵素免疫分析法(enzyme-linked immunosorbant assay,ELISA)检测肠组织肿瘤坏死因子(tumor necrosis factor,TNF)-α、白介素(interleukin,IL)-1β及IL-10水平.结果:两治疗组体质量较模型组增加,但差异无统计学意义;两治疗组疾病活动指数(disease activity index,DAI)评分较模型组明显下降(0.70±1.06,0.67±0.71vs2.38±1.51,P<0.05).徐长卿组、巴柳氮组结肠大体损伤及病理评分较模型组显著下降(1.05±0.83,1.06±0.85vs2.94±0.94;1.65±1.67,2.00±1.80vs6.00±1.67,均P<0.01).徐长卿组较模型组TNF-α、IL-1β水平明显降低(P<0.01),IL-10水平无统计学差异.巴柳氮组较模型组TNF-α、IL-1β、IL-10水平均明显降低(P<0.01).结论:徐长卿能有效改善TNBS诱导的大鼠结肠炎,其机制可能与调节细胞因子水平有关.     

微生态制剂对实验性大鼠结肠炎的治疗

目的 评价微生态制剂双歧三联活菌对三硝基苯磺酸钠(TNBS)诱导的大鼠结肠炎的疗效,探索炎症性肠病(IBD)治疗的新方法.方法 成年雌性SD大鼠50只,随机分为对照组(G1)、模型组(G2)、双歧三联活菌治疗组(G3)、奥沙拉秦治疗组(G4)、双歧三联活菌和奥沙拉秦联合治疗组(G5),每组10只.ELISA法检测各组的血清C反应蛋白(CRP)、TNFα、IL-10水平,分光光度法检测肠组织髓过氧化物酶(MPO)活力,并对肠组织进行病理组织学分析.结果 治疗后,G1组肠组织结构正常,血清CRP、TNFα、IL-10水平、结肠黏膜损伤指数(CMDI)及肠组织MPO活力显著低于G2组(P<0.001);G2组肠组织炎症程度最莺,血清CRP、TNFα、IL-10水平、CMDI及肠组织MPO活力最高,P<0.05;3个治疗组G3、G4、G5组的肠组织炎症呈不同程度消散,血清CRP、TNFα、IL-10水平及肠组织MPO活力呈不同程度下降,以G5组最显著,P<0.05;G2组血清CRP、TNFα、IL-10及肠组织MPO活力均分别与CMDI呈正相关,P<0.001.结论 双歧三联活菌能有效改善TNBS诱导的大鼠结肠炎,其机制可能与调节细胞因子水平有关.     

The Role of the Tumor Necrosis Factor Receptor in 2,4,6-Trinitrobenzene Sulfonic Acid (TNBS)-Induced Colitis in Mice

We investigated the effect of TNBS administration using TNF-receptor knockout mice to elucidate the role of TNF receptors in chronic inflammation of the colon. Histologically, inflammatory cell scores showed no significant differences among TNBS-administered groups, while tissue damage scores were significantly lower in TNFR-1KO and TNFR-1,2KO than in WT. The apoptotic indexes of lamina propria mononuclear cells (LPMC) of all TNBS-administered groups were significantly lower than that of controls. TNF-α mRNA expression in the colon was significantly higher in all TNBS-administered groups than in controls. And NF-κ B activities were enhanced in WT and TNFR-2KO compared with controls. Our data indicate that the TNF/TNFR-1 signaling system mediates mucosal damage through the enhancement of NF-κ B activity and that continuous infiltration of TNF-producing cells, probably a key pathogeneses of colitis, may be closely associated with defective apoptosis of LPMC, which is possibly independent of the TNF/TNFR signaling system in TNBS-induced colitis.     

英夫利昔、沙利度胺对大鼠实验性结肠炎的治疗作用及其机制研究

炎症性肠病（IBD）是一种病因尚未明确的非特异性肠道炎症性疾病,传统治疗方法疗程长．疗效欠佳,容易反复发作。目的：观察并比较英夫利昔、沙利度胺对TNBS灌肠诱发的大鼠结肠炎治疗效果．并初步探讨两者治疗IBD的作用机制。方法：46只Sprague-Dawley大鼠随机分成正常对照组（n=10）、结肠炎组（n=12）、英夫利昔组（n=12）、沙利度胺组（n=12）,后三组给予TNBS／乙醇灌肠诱导大鼠结肠炎模型。造模后第1d,英夫利昔组、沙利度胺组分别给予英夫利昔腹腔注射5mg·kg-1．d～、沙利度胺管喂200mg．kg-．d～,连续7d后处死。行疾病活动指数（DAI）、大体形态损伤指数（CMDI）和组织损伤指数（TDI）评分;以Real．timePCR、蛋白质印迹法和免疫组化分别检测结肠组织TNF-d、VEGF、caspase-3mRNA和蛋白表达;TUNEL法检测结肠上皮细胞凋亡情况。结果：结肠炎组大鼠DAI、CMDI、TDI评分均显著高于正常对照组（P〈O．05）,TNF-a、VEGF、caspase-3mRNA和蛋白表达显著升高（P〈O．05）．结肠上皮细胞凋亡显著增加;给予英夫利昔或沙利度胺治疗后,上述指标均显著改善（P〈0．05）。结论：本实验成功构建了TNBS大鼠结肠炎模型,英夫利昔、沙利度胺对大鼠结肠炎均有明显的治疗效果,两者通过抑制TNF-a VEGF、caspase-3的表达,对IBD免疫、血管生成、凋亡过程起调节作用。     

Kynurenine plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate-induced colitis in mice

BACKGROUND Inflammatory bowel disease,such as Crohn’s disease and ulcerative colitis,is characterized by chronic intestinal inflammation leading to intestinal mucosal damage.Inflammatory bowel disease causes dysregulation of mucosal T cell responses,especially the responses of CD4+T cells.Previously,we demonstrated that indoleamine-2,3-dioxygenase plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate(TNBS)-induced colitis.Although indoleamine-2,3-dioxygenase exerts immunosuppressive effects by altering the local concentration of tryptophan(Trp)and immunomodulatory Trp metabolites,the specific changes in immune regulation during colitis caused by Trp metabolites and its related enzymes remain unclear.AIM To investigate role of kynurenine 3-monooxygenase(KMO)in TNBS-induced colitis and involvement of Trp metabolites in maintenance of intestinal homeostasis.METHODS Colitis was induced in eight-week-old male KMO+/+or KMO−/−mice of C57BL/6N background using TNBS.Three days later,the colon was used for hematoxylin-eosin staining for histological grading,immunohistochemical or immunofluorescence staining for KMO,cytokines,and immune cells.Inflammatory and anti-inflammatory cytokines were measured using quantitative RT-PCR,and kynurenine(Kyn)pathway metabolites were measured by high-performance liquid chromatography.The cell proportions of colonic lamina propria and mesenteric lymph nodes were analyzed by flow cytometry.RESULTS KMO expression levels in the colonic mononuclear phagocytes,including dendritic cells and macrophages increased upon TNBS induction.Notably,KMO deficiency reduced TNBS-induced colitis,resulting in an increased frequency of Foxp3+regulatory T cells and increased mRNA and protein levels of antiinflammatory cytokines,including transforming growth factor-βand interleukin-10.CONCLUSION Absence of KMO reduced TNBS-induced colitis via generation of Foxp3+regulatory T cells by producing Kyn.Thus,Kyn may play a therapeutic role in colon protection during colitis.     

灭活血吸虫卵对实验性结肠炎肠黏膜的影响

目的 研究灭活血吸虫卵对2,4,6一三硝基苯磺酸(tinitrobenzene sulfonic acid,TNBS)诱导小鼠结肠炎肠黏膜紧密连接蛋白ZO-1和Occludin基因及蛋白表达影响及其机制.方法 清洁级BALB/C雌性小鼠50只分成对照组(10只)、TNBS+0.9%氯化钠溶液组(20只)和TNBS+血吸虫卵组(20只).TNBS+血吸虫卵组在造模前第3、14天分别给予腹腔注射冰冻灭活血吸虫卵10 000个(1 ml冰0.9%氯化钠溶液混悬液);TNBS+0.9%氯化钠溶液组给予相同体积的冰0.9%氯化钠溶液腹腔注射.后两组予TNBS溶液灌肠(100 mg/kg)建立结肠炎模型,建模后第7天处死存活小鼠,观察各组小鼠结肠的大体形态和HE染色光镜下病理特征;荧光实时定量PCR法测定结肠组织的Occludin和ZO-1基因表达;Western印迹法检测蛋白表达;免疫组化法测定结肠组织紧密连接蛋白表达分布.结果 TNBS+血吸虫卵组小鼠死亡率较TNBS+0.9%氯化钠溶液组明显下降(15%比30%).TNBS+0.9%氯化钠溶液组组织学评分为(4.21±0.40)分,较TNBS+血吸虫卵组和对照组高[(1.74±0.10)和(1.06±0.20)分,P<0.05].TNBS+0.9%氯化钠溶液组ZO-1和Occludin mRNA表达量较对照组显著下降(P<0.01),而TNBS+血吸虫卵组较TNBS+0.9%氯化钠溶液组显著增加(P<0.05).TNBs+0.9%氯化钠溶液组ZO-1蛋白相对灰度值较正常对照组降低50.3%(P<0.05),而TNBS+血吸虫卵组较TNBS+0.9%氯化钠溶液增加41.1%(P<0.05);TNBS+0.9%氯化钠溶液组Occludin相对灰度值较对照组下降48.7%(P<0.05),而血吸虫卵组较TNBS+0.9%氯化钠溶液组增加23.6%(P<0.05).ZO-1、Occludin蛋白染色强度TNBS+0.9%氯化钠溶液组分布均较对照组间增强(P<0.01),而TNBS+血吸虫卵组染色强度信号分布较TNBS+0.9%氯化钠溶液组显著增加(P<0.05).结论 灭活血吸虫卵能在细胞水平加强紧密连接蛋白ZO-1、Occludin聚集及表达,通过稳定紧密连接蛋白,增加肠道黏膜屏障功能,显著改善实验性结肠炎的肠道炎症反应.     

Effects of statins on experimental colitis in normocholesterolemic rats

OBJECTIVE: The results of previous studies suggest that statins have a direct anti-inflammatory effect that is not directly related to their cholesterol-lowering activity. The aim of this study was to investigate the effect of simvastatin (SIM) and fluvastatin (FLU) on trinitrobenzene sulfonic acid (TNBS)-induced colonic inflammation in rats. MATERIAL AND METHODS: The drugs were given for 3 days (0.1 and 1 mg/kg day-1; intraperitoneally) after induction of colitis. The lesions in the distal colon were scored at the macroscopic and microscopic level. Tissue malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were assessed and formation of reactive oxygen species and peroxynitrite was monitored by chemiluminescence (CL) assay. Trunk blood was collected for the measurement of serum tumor necrosis factor (TNF)-alpha level. RESULTS: Treatment with SIM reduced the lesion score of the colitis group at macroscopic level (p<0.05), but there was no effect of treatment with FLU. The increase in colonic MDA level of the colitis group was reduced by both drugs at all doses (p<0.05-0.001). The decrease in GSH and the an increase in MPO activity in the colitis group were reversed by SIM at all doses (p<0.01), but FLU had no effect. An increase in colonic lucigenin CL value in the colitis group was reduced by SIM and FLU at all doses (p<0.001) and an increase in peroxynitrite ratio in the colitis group showed a significant reduction in SIM-treated groups; FLU reduced this effect at a dose of 1 mg/kg (p<0.01). An increase in tissue collagen content and serum TNF-alpha level in the colitis group was reversed by both drugs at all doses (p<0.001). CONCLUSIONS: SIM and FLU seemed to be beneficial in a TNBS-induced rat colitis model through the prevention of lipid peroxidation, superoxide generation, cytokine production and neutrophil accumulation.     

培菲康对实验性溃疡性结肠炎大鼠TNF-α、IL-10水平的影响

目的阐明培菲康对三硝基苯磺酸钠(TNBS)诱导的大鼠溃疡性结肠炎(UC)TNF-α、IL-10水平的影响,寻求UC治疗的有效新途径。方法成年雌性SD大鼠50只,随机分成5组(n=10):正常对照组(G1)、模型对照组(G2)、培菲康治疗组(G3)、奥沙拉嗪治疗组(G4)、培菲康和奥沙拉嗪联合治疗组(G5),经不同处理和治疗后,通过免疫组化染色观测各组大鼠结肠组织中TNF-α(两步法)、IL-10(S-P法)表达情况,通过实时荧光定量PCR分析结肠组织中TNF-α、IL-10mRNA的表达水平。结果G1组各指标显著低于G2组(P0.001),肠组织结构正常;与G2组相比,G3、G4、G5组TNF-α、IL-10细胞阳性率和TNF-α、IL-10mRNA的表达水平显著降低(P0.001);与G3或G4组相比,G5组TNF-α、IL-10细胞阳性率和TNF-α、IL-10mRNA的表达水平也显著降低(P0.001);G3或G4组之间,TNF-α、IL-10细胞阳性率及TNF-αmRNA水平无差别(P0.05),而G4组IL-10mRNA水平明显低于G3组(P0.001)。结论TNF-α、IL-10在溃疡性结肠炎(UC)的发生、发展过程中起重要作用,培菲康能明显降低该过程中肠组织TNF-α、IL-10的表达水平,可能通过调控这两个细胞因子的表达而发挥疗效。     

Proteome profiling of spinal cord and dorsal root ganglia in rats with trinitrobenzene sulfonic acid-induced colitis

AIM: To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis.METHODS: The colonic myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) level were determined. A two-dimensional electrophoresis (2-DE)-based proteomic technique was used to profile the global protein expression changes in the DRG and spinal cord of the rats with acute colitis induced by intra-colonic injection of TNBS.RESULTS: TNBS group showed significantly elevated colonic MPO activity and increased TNF-α level. The proteins derived from lumbosacral enlargement of the spinal cord and DRG were resolved by 2-DE; and 26 and 19 proteins that displayed significantly different expression levels in the DRG and spinal cord were identified respectively. Altered proteins were found to be involved in a number of biological functions, such as inflammation/immunity, cell signaling, redox regulation, sulfate transport and cellular metabolism. The overexpression of the protein similar to potassium channel tetramerisation domain containing protein 12 (Kctd 12) and low expression of proteasome subunit α type-1 (psma) were validated by Western blotting analysis.CONCLUSION: TNBS-induced colitis has a profound impact on protein profiling in the nervous system. This result helps understand the neurological pathogenesis of inflammatory bowel disease.     

Induction of Murine TNBS Colitis Is Strictly Controlled by a Modified Method Using Continuous Inhalation Anesthesia with Sevoflurane

Background

Trinitrobenzenesulfonic acid (TNBS)-induced colitis is one of the most widely used experimental colitis models. However, there is no standard procedure for inducing colitis by TNBS because it is difficult to achieve a uniform distribution of colitis. We have developed a modified method of murine TNBS-induced colitis that involves inhalation anesthesia with sevoflurane combined with both single and repeated TNBS administrations.

Aims

To compare the usefulness of our newly developed method for inducing murine TNBS-induced colitis with that of conventional intraperitoneal anesthesia.

Methods

TNBS in ethanol was administered to C57BL/6J mice held in an inverted vertical position either under continuous inhalation anesthesia with sevoflurane, in accordance with our newly developed method, or by intraperitoneal injection with 2.5 % avertin, in accordance with the conventional procedure. Body weight change, cytokine profile, and histological findings were examined during the course of colitis.

Results

The dispersion of anesthesia time, TNBS retention time, and nadir weight during the course of colitis was decreased using the newly developed method compared with the conventional procedure. Optimization of the modified TNBS-induced colitis, as evidenced by the predominant expression of Th1 and Th17 cytokines on day 7, was attained by the injection of 2.25 mg TNBS in 55 % ethanol. Regulation of the TNBS retention time using inhalation anesthesia with sevoflurane allowed strict control of the disease severity of TNBS-induced colitis. Using the modified method we were also able to develop a chronic TNBS-induced colitis model by repeated TNBS administration without excessive mortality of the mice.

Conclusions

Our modified method for murine TNBS-induced colitis using continuous inhalation anesthesia with sevoflurane provides a better experimental colitis model following both single and repeated TNBS administrations.     

Therapeutic and prophylactic thalidomide in TNBS-induced colitis： Synergistic effects on TNF-α, IL-12 and VEGF production

AIM： To evaluated the therapeutic and prophylactic effect of thalidomide on 2, 4, 6-trinitrobenzene sulfonic acid （TNBS）-induced colitis. Thalidomide has been reported to downregulate the expression of tumor necrosis factor α （TNF-α）, IL-12, and vascular endothelial growth factor （VEGF）, hallmarks of intestinal inflammation in Crohn＇s disease （CD）.
METHODS： Male Wistar rats were divided in five groups of ten animals each. Four groups received a rectal infusion of TNBS in ethanol. The first group was sacrificed 7 d after colitis induction. The second and third groups received either thalidomide or placebo by gavage and were sacrificed at 14 d. The fourth group received thalidomide 6 h before TNBS administration, and was sacrificed 7 d after induction. The fifth group acted as the control group and colitis was not induced. Histological inflammatory scores of the colon were performed and lamina propria CD4＋ T cells, macrophages, and VEGF＋ cells were detected by immunohistochemistry. TNF-α and IL-12 were quantified in the supernatant of organ cultures by ELISA.
RESULTS： Significant reduction in the inflammatory score and in the percentage of VEGF＋ cells was observed in the group treated with thalidomide compared with animals not treated with thalidomide. Both TNF-α and IL-12 levels were significantly reduced among TNBS induced colitis animals treated with thalidomide compared with animals that did not receive thalidomide. TNF-α levels were also significantly reduced among the animals receiving thalidomide prophylaxis compared with untreated animals with TNBS-induced colitis. Intestinal levels of TNF-α and IL-12 were significantly correlated with the inflammatory score and the number of VEGF＋ cells.
CONCLUSION： Thalidomide significantly attenuates TNBS-induced colitis by inhibiting the intestinal production of TNF-α, IL-12, and VEGF. This effect may support the use of thalidomide as an alternate approach in selected patients with CD.     

Therapeutic and prophylactic thalidomide in TNBS-induced colitis: Synergistic effects on TNF-α, IL-12 and VEGF production

AIM: To evaluated the therapeutic and prophylactic effect of thalidomide on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Thalidomide has been reported to downregulate the expression of tumor necrosis factor α (TNF-α), IL-12, and vascular endothelial growth factor (VEGF), hallmarks of intestinal inflammation in Crohn's disease (CD).METHODS: Male Wistar rats were divided in five groups of ten animals each. Four groups received a rectal infusion of TNBS in ethanol. The first group was sacrificed 7 d after colitis induction. The second and third groups received either thalidomide or placebo by gavage and were sacrificed at 14 d. The fourth group received thalidomide 6 h before TNBS administration, and was sacrificed 7 d after induction. The fifth group acted as the control group and colitis was not induced. Histological inflammatory scores of the colon were performed and lamina propria CD4+ T cells, macrophages, and VEGF+ cells were detected by immunohistochemistry. TNF-α and IL-12 were quantified in the supernatant of organ cultures by ELISA.RESULTS: Significant reduction in the inflammatory score and in the percentage of VEGF+ cells was observed in the group treated with thalidomide compared with animals not treated with thalidomide. Both TNF-α and IL-12 levels were significantly reduced among TNBS induced colitis animals treated with thalidomide compared with animals that did not receive thalidomide.TNF-α levels were also significantly reduced among the animals receiving thalidomide prophylaxis compared with untreated animals with TNBS-induced colitis. Intestinal levels of TNF-α and IL-12 were significantly correlated with the inflammatory score and the number of VEGF+ cells.CONCLUSION: Thalidomide significantly attenuates TNBS-induced colitis by inhibiting the intestinal production of TNF-α, IL-12, and VEGF. This effect may support the use of thalidomide as an alternate approach in selected patients with CD.