清肠栓对溃疡性结肠炎大鼠结肠黏膜纤丝状肌动蛋白的影响

[目的]探讨复方中药清肠栓对溃疡性结肠炎(UC)大鼠结肠黏膜纤丝状肌动(F-actin)蛋白的修复作用。[方法]清洁级雄性SD大鼠36只,随机分为正常组,模型组,柳氮磺胺吡啶(SASP)组,清肠栓高、中、低剂量组,每组6只。选用三硝基苯磺酸(TNBS)诱导的UC大鼠模型,采用免疫荧光的方法观察各组大鼠结肠黏膜F-actin蛋白的表达,并运用图像分析软件进行平均光密度测定,观察清肠栓对UC大鼠结肠屏障的修复作用。[结果]UC发病对结肠黏膜细胞骨架系统严重损害,模型组大鼠结肠黏膜F-actin蛋白几乎完全被破坏,荧光染色暗淡。图像分析测其平均光密度较正常组明显降低(P<0.01)。清肠栓能不同程度减轻UC黏膜的破坏,改善F-actin蛋白的分布,并使其表达升高(P<0.01)。[结论]清肠栓能有效地调节肠黏膜屏障功能,有效抑制UC大鼠结肠通透性的升高,改善肠黏膜屏障功能,促进溃疡愈合。     

清肠栓对大鼠溃疡性结肠炎急性期模型CXCR2的影响

[目的]观察清肠栓对大鼠溃疡性结肠炎（UC）急性期模型结肠黏膜CXCR2的影响.[方法]SD大鼠48只,分为正常组、模型组、清肠栓组和SASP组,每组12只.用三硝基苯磺酸（TNBs）诱导大鼠UC急性期模型.造模后第3天开始给药,连续给药7d后处死.Elisa、免疫组化检测病变部位结肠组织中的CXCR2含量及蛋白表达.[结果]模型组CXCR2含量及蛋白表达较正常组明显升高（P＜0.05）,清肠栓及SASP组较模型组均降低（P＜0.05）.[结论]清肠栓通过调节结肠黏膜CXCR2蛋白含量,减少中性粒细胞向病变局部黏膜组织的趋化和激活,从而起到缓解病变部位炎症的作用.     

清肠栓对三硝基苯磺酸诱导结肠炎大鼠结肠黏膜地址素细胞黏附分子-1表达的影响

目的:探讨黏膜地址素细胞黏附分子-1(MAdCAM-1)在三硝基苯磺酸(TNBS)诱导大鼠结肠炎发病过程中的作用:研究清肠栓是否通过抑制MAdCAM-1在结肠黏膜的表达,而发挥其抗炎愈疡作用.方法:用TNBS制备实验性大鼠结肠炎模型,大鼠随机分为清肠栓高剂量组、清肠栓低剂量组、柳氮磺胺吡啶组(SASP)、模型Ⅰ组、模型Ⅱ组及正常组.模型Ⅰ组造模3 d时,其余5组在给药7 d时处死大鼠.取大鼠结肠病变部位标本,进行组织病理学评价,用双抗体夹心酶联免疫吸附法检测结肠组织中LTB4和TNF-α水平,免疫组化染色法和Western blot分析法检测结肠黏膜MAdCAM-1蛋白表达.结果:造模3 d时,模型Ⅰ组大鼠结肠黏膜出现明显组织损伤;经过7 d处理后,清肠栓组大鼠黏膜组织损伤减轻.模型组结肠黏膜LTB4和TNF-α水平比正常组上升(436.38±66.56,396.81±69.43 vs 203.76±42.84;394.78±61.53,413.43±47.39 vs 233.84±55.24,均P<0.01);与模型Ⅱ组比较,各治疗组LTB4和TNF-α水平均下降,尤以清肠栓高剂量组下降明显(275.74±36.35,282.72±47.94,P<0.01).正常组大鼠结肠黏膜固有层MAdCAM-1可见少量表达,模型Ⅰ组大鼠结肠黏膜阳性染色细胞数明显增多:与模型Ⅱ组比较,清肠栓高剂量组、低剂量组和SASP组MAdCAM-1表达均明显下调,尤其在清肠栓高剂量组下调更为显著.结论:清肠栓通过抑制结肠黏膜促炎症因子LTB4和TNF-α释放,以及下调MAdCAM-1表达.而发挥其抗炎愈疡作用.     

清肠栓调节三硝基苯磺酸诱导结肠炎大鼠结肠黏膜细胞增殖的影响

[目的]从细胞增殖动力学角度探讨清肠栓促进结肠溃疡愈合的作用机制.[方法]制备三硝基苯磺酸(TNBS)诱导结肠炎大鼠.造模3 d,分为清肠栓高剂量组、清肠栓低剂量组、柳氮磺胺吡啶(SASP)组、模型对照组、模型组和正常组.给药7 d后,取大鼠结肠病变部位标本,进行组织学评价,运用AB-PAS染色观察杯状细胞数量及其分泌黏液功能,免疫组化染色法检测增殖细胞核抗原(PCNA)表达.[结果]与清肠栓低剂量组、SASP组、模型对照组和正常组比较,清肠栓高剂量组大鼠结肠黏膜炎症消除和溃疡愈合,杯状细胞数量及黏液增加,溃疡边缘腺体细胞增殖加强,PCNA表达增加(P＜0.05).[结论]清肠栓具有促进结肠炎大鼠结肠黏膜细胞增殖、增加杯状细胞的数量和分泌黏液的水平等作用,能够促进结肠溃疡愈合过程.     

清肠栓对大鼠溃疡性结肠炎白细胞介素受体表达的影响

[目的]从白细胞介素受体(IL-R)角度探讨中药清肠栓防治溃疡性结肠炎(UC)的作用机制.[方法]三硝基苯磺酸(TNBS)诱导建立大鼠UC模型;41只雄性SD大鼠随机分成6组(正常组,模型组,5-氨基水杨酸栓组,清肠栓大剂量、中剂量、小剂量组),治疗组均分别予肠道给药;1周后处死,ELISA法检测血清、结肠组织可溶性IL-R(sIL-R)2,4、6水平;RT-PCR半定量法检测结肠黏膜IL-2R、IL-4R、IL-6R mRNA的表达.[结果]清肠栓各剂量组sIL-2R、sIL-6R的水平降低,与模型组比较P＜0.01,中、大剂量组IL-2R、IL-6R mRNA表达降低,与模型组比较P＜0.01或＜0.05,清肠栓各剂量组皆有降低IL-4R mRNA表达的趋势,与模型组比较P＞0.05.[结论]清肠栓有效防治UC,其作用机制与降低slL-2R、sIL-6R水平,下调IL-2R、IL-6R mRNA表达,抑制T淋巴细胞活化增殖,减少炎症递质产生有关.     

中药清肠栓对溃疡性结肠炎大鼠白细胞介素4及10 mRNA表达的影响

[目的]研究中药清肠栓对实验性溃疡性结肠炎(UC)大鼠结肠组织白细胞介素4(IL-4)、白细胞介素10(IL-10)mRNA表达的影响。[方法]用三硝基苯磺酸(TNBS)复制实验性大鼠UC模型,将之随机分为清肠栓大、小剂量组,醋酸泼尼松组,空白对照组,模型对照组,并设正常对照组。观察大鼠结肠组织病理改变,用逆转录-聚合酶链式反应(RT-PCR)检测模型大鼠结肠组织IL-4、IL-10 mRNA的表达。[结果]①模型组和空白对照组结肠组织IL-4、IL-10 mRNA表达较正常组显著降低(P<0.05)。②清肠栓大、小剂量组,醋酸泼尼松组结肠组织IL-4、IL-10 mRNA表达较模型组和空白对照组明显升高(P<0.05)。[结论]清肠栓能促进结肠组织抑炎细胞因子IL-4、IL-10 mRNA的表达。     

红花注射液对溃疡性结肠炎大鼠IL-4和IL-1β表达的影响

目的:观察红花注射液(injection of carthamus tinctorius,ICT)对2,4,6-三硝基苯磺酸(2,4,6-trinitrobenzene sulfonic acid,TNBS)所致大鼠溃疡性结肠炎(ulcerative colitis,UC)的治疗作用,并通过观察ICT对大鼠结肠黏膜白细胞介素-4(interleukin-4,IL-4)和白细胞介素-1β(interleukin-1β,IL-1β)蛋白及mRNA表达的影响,初步探讨其治疗UC的作用机制.方法:30只Wistar大鼠随机分为实验组、模型组和对照组3组,每组各10只,其中实验组和模型组大鼠分别用TNBS灌肠,以复制UC模型,同时实验组给予ICT干预治疗.疗程结束后,观察疾病活动指数(disease activity index,DAI),剖取大鼠8cm结肠,进行结肠大体形态评分,将标本进行HE染色,并进行组织学损伤评分;采用免疫组织化学染色及RT-PCR检测结肠IL-4和IL-1β蛋白及mRNA的表达.结果:实验组与模型组相比,UC大鼠的DAI、结肠黏膜的大体形态及组织学损伤明显改善(均P<0.05),实验组IL-4蛋白及mRNA的表达与正常对照组相比无显著性差异(P>0.05),与模型组相比显著升高(P<0.05);模型组及实验组IL-1β蛋白及mRNA的表达较正常对照组显著升高(P<0.05),而实验组较模型组显著降低(P<0.05).结论:ICT对TNBS法诱导的大鼠UC有治疗作用,其机制可能是通过上调抗炎因子IL-4的释放和抑制促炎细胞因子IL-1β的表达而起作用.     

溃结灵对溃疡性结肠炎大鼠结肠黏膜T L R4蛋白水平的作用

目的:观察溃疡性结肠炎(UC)大鼠结肠黏膜Toll样受体4(TLR4)的变化特点及溃结灵对TLR4的影响.方法:采用三硝基苯磺酸(TNBS)法制作UC大鼠模型,大鼠随机分为6组:正常对照组、模型对照组、溃结灵低、中、高剂量组、阳性药柳氮磺胺吡啶(SASP)组.治疗10d后处死大鼠取新鲜结肠黏膜标本提取全细胞蛋白.采用蛋白免疫印迹(Westem blot)方法对TLR4的蛋白表达水平进行检测,以β-actin作为内参,以目的蛋白与β-actin密度的比值作为目的蛋白的相对含量并进行统计学分析.结果:模型组TLR4蛋白相对表达量明显高于正常组(0.843±0.201 vs 0.472±0.072,P＜0.01);溃结灵高剂量组TLR4相对表达量明显低于模型组(0.620±0.178 vs 0.843±0.201,P＜0.05).结论:TLR4可能参与了uc大鼠的发病过程,溃结灵使TNBS法UC大鼠模型结肠黏膜TLR4的蛋白表达水平明显降低,这可能是其治疗UC作用的机制之一.     

甘草酸二铵对溃疡性结肠炎大鼠M30表达的影响

目的:观察甘草酸二铵(diammonium glycyrrhi-zinate,DG)对2,4,6-三硝基苯磺酸(2,4,6-trin-itrobenzene sulfonic acid,TNBS)诱导的大鼠溃疡性结肠炎(ulcerative colitis,UC)的疗效及其对大鼠结肠组织M30及Fas/FasL蛋白表达的影响,继而从细胞凋亡方面探讨DG治疗大鼠UC可能的作用机制.方法:♀Wistar大鼠30只,随机分为正常对照组、模型组和DG组,每组10只.用TNBS/乙醇灌肠法复制大鼠UC模型,10d后收集结肠标本,观察大鼠疾病活动指数(disease activity index,DAI)、结肠大体形态损伤评分和组织学改变,用免疫组织化学法观察大鼠结肠黏膜中M30及Fas/FasL蛋白的表达.结果:与正常对照组相比,DG组、模型组DAI评分、结肠大体形态损伤评分和组织学损伤评分均显著增高(7.06±0.80vs0.32±0.14;6.03±0.61vs0.19±0.16;5.84±0.53vs0.22±0.11,P<0.01);而与模型组相比,DG治疗组能显著改善UC症状(3.33±0.27vs7.06±0.80;3.29±0.36vs6.03±0.61;2.98±0.24vs5.84±0.53,P<0.05).模型组大鼠M30及Fas/FasL蛋白表达水平明显高于正常组(5.76±0.66vs0.42±0.18;26.62±4.20vs10.81±2.20;17.11±3.12vs6.02±1.02,P<0.01);与模型组相比,DG治疗组M30及Fas/FasL蛋白表达显著降低(2.24±0.48vs5.76±0.66;17.23±3.20vs26.62±4.20;11.02±2.12vs17.11±3.12,P<0.05).结论:DG对TNBS诱导的大鼠UC有较好的疗效,DG通过下调Fas/FasL的表达抑制结肠上皮细胞的凋亡,这可能是其减轻结肠黏膜损伤的机制之一.     

三黄汤灌肠对溃疡性结肠炎大鼠治疗作用研究

[目的]探讨三黄汤灌肠对三硝基苯磺酸(TNBS)诱导溃疡性结肠炎(UC)模型大鼠的疗效。[方法]采用TNBS诱导制备UC大鼠模型45只,随机分为模型组、阳性对照组及中药治疗组,各15只,并选未造模大鼠15只作为正常对照组。各组均灌肠给药,模型组和正常对照组予0.9%氯化钠注射液,阳性对照组予柳氮磺吡啶0.5 g/kg,中药治疗组予三黄汤浓煎剂60 g/kg,各组均按10 ml/kg每日灌肠1次。给药时间从造模后第3天开始,连续7 d。第11天观察各组大鼠结肠黏膜损伤指数(CMDI)及黏膜病理组织学情况。[结果]中药治疗组结肠黏膜病理损伤明显改善,CMDI为(1.5±0.535)分,与模型组的(3.55±1.214)分比较差异有统计学意义(P0.05);与阳性对照组的(2.63±1.188)分比较差异有统计学意义(P0.05)。在肉眼及电镜下观察发现,中药治疗组大鼠结肠黏膜较模型组、阳性对照组明显改善。[结论]三黄汤灌肠对TNBS诱导的大鼠UC疗效确切,能显著改善结肠黏膜的充血水肿、溃疡、糜烂等。     

Schistosoma japonicum ova maintains epithelial barrier function during experimental colitis

AIM: To evaluate the impacts of Schistosoma japonicum (S. japonicum) ova on the tight junction barriers in a trinitrobenzenesulfonic acid (TNBS)-induced colitis model.METHODS: Balb/c mice were randomly divided into three groups: control group; TNBS⁺ova^- group and TNBS⁺ova⁺ group. TNBS was used intracolonic to induce colitis and mice of the TNBS⁺ova⁺ group were pre-exposed to S. japonicum ova as a prophylactic intervention. Colon inflammation was quantified using following variables: mouse mortality, weight loss, colon extent and microscopic inflammation score. Serum expression of tumor necrosis factor-α and interferon-γ were assessed to evaluate the systemic inflammatory response. NOD2 and its mRNA were also tested. Bacterial translocations were tested by culturing blood and several tissues. ZO-1 and occludin were chosen as the representations of tight junction proteins. Both the proteins and mRNA were assessed.RESULTS: Ova pre-treatment contributed to the relief of colitis and decreased the mortality of the models. NOD2 expression was significantly downregulated when pretreated with the ova. The TNBS injection caused a significant downregulation of ZO-1 and occludin mRNA together with their proteins in the colon; ova pre-exposure reversed these alterations. Treatment with S. japonicum ova in the colitis model caused lower intestinal bacterial translocation frequency.CONCLUSION: S. japonicum ova can maintain epithelial barrier function through increasing tight junction proteins, thus causing less exposure of NOD2 to the luminal antigens which may activate a series of inflammatory factors and induce colitis.     

氯吡格雷对大鼠急性胃黏膜损伤愈合的影响及机制

目的:研究氯吡格雷对大鼠急性胃黏膜损伤愈合的影响作用及其机制.方法:40只健康♂SD大鼠随机分为4组,每组10只:阴性对照组、单纯损伤组、10mg/kg氯吡格雷处理组、30mg/kg氯吡格雷处理组;以大剂量阿司匹林灌胃制造大鼠急性胃黏膜损伤模型后,对氯吡格雷处理组的大鼠以相应剂量的氯吡格雷进行灌胃处理,给药3d,每天1次.分别测定各组大鼠的胃黏膜损伤指数(lesionindex,LI);观察大鼠胃黏膜组织学变化;免疫组织化学法检测各组紧密连接蛋白Occludin的表达情况;免疫蛋白印迹法(Westernblot)检测紧密连接蛋白Occludin、ZO-1以及MAPK信号通路中磷酸化P38、磷酸化ERK及磷酸化JNK蛋白的表达量.结果:与损伤组相比,氯吡格雷处理组大鼠胃黏膜损伤加重,且30mg/kg组损伤重于10mg/kg组(39.8±5.05vs35.3±3.86,P<0.05);在阴性对照组、单纯损伤组、10mg/kg氯吡格雷处理组、30mg/kg氯吡格雷处理组中,大鼠胃黏膜中的紧密连接蛋白Occludin、ZO-1蛋白的表达逐渐下降,呈递减趋势(P=0.000),而磷酸化P38、磷酸化ERK蛋白表达则逐渐上升,呈递增趋势(P=0.000).结论:氯吡格雷能够抑制大鼠急性胃黏膜损伤的愈合,其可能是通过激活MAPK中的p38和ERK信号通路,下调胃黏膜上皮细胞间紧密连接蛋白Occludin和ZO-1的表达,破坏大鼠胃黏膜的屏障.     

Oral treatment with plecanatide or dolcanatide attenuates visceral hypersensitivity via activation of guanylate cyclase-C in rat models

AIM To investigate the effects of plecanatide and dolcanatide on maintenance of paracellular permeability, integrity of tight junctions and on suppression of visceral hypersensitivity. METHODS Transport of fluorescein isothiocyanate(FITC)-dextran was measured to assess permeability across cell monolayers and rat colon tissues. Effects of plecanatide and dolcanatide on the integrity of tight junctions in Caco-2 and T84 monolayers and on the expression and localization of occludin and zonula occludens-1(ZO-1) were examined by immunofluorescence microscopy. Anti-nociceptive activity of these agonists was evaluated in trinitrobenzene sulfonic acid(TNBS)-induced inflammatory as well as in non-inflammatory partial restraint stress(PRS) rat models. Statistical significance between the treatment groups in the permeability studies were evaluated using unpaired t-tests.RESULTS Treatment of T84 and Caco-2 monolayers with lipopolysaccharide(LPS) rapidly increased permeability, which was effectively suppressed when monolayers were also treated with plecanatide or dolcanatide. Similarly, when T84 and Caco-2 monolayers were treated with LPS, cell surface localization of tight junction proteins occludin and ZO-1 was severely disrupted. When cell monolayers were treated with LPS in the presence of plecanatide or dolcanatide, occludin and ZO-1 were localized at the cell surface of adjoining cells, similar to that observed for vehicle treated cells. Treatment of cell monolayers with plecanatide or dolcanatide without LPS did not alter permeability, integrity of tight junctions and cell surface localization of either of the tight junction proteins. In rat visceral hypersensitivity models, both agonists suppressed the TNBS-induced increase in abdominal contractions in response to colorectal distension without affecting the colonic wall elasticity, and both agonists also reduced colonic hypersensitivity in the PRS model. CONCLUSION Our results suggest that activation of GC-C signaling might be involved in maintenance of barrier function, possibly through regulating normal localization of tight junction proteins. Consistent with these findings, plecanatide and dolcanatide showed potent antinociceptive activity in rat visceral hypersensitivity models. These results imply that activation of GC-C signaling may be an attractive therapeutic approach to treat functional constipation disorders and inflammatory gastrointestinal conditions.     

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.     

Increase in the Tight Junction Protein Claudin-1 in Intestinal Inflammation

Background and Aims

Studies have shown a decrease in key tight junction (TJ) proteins such as ZO-1 and occludin in both inflammatory bowel disease (IBD) and experimental models of inflammation. Our group has also shown an increase in claudin-1 in experimental colitis.

Methods

IEC-18 cells were treated with increasing doses of tumor necrosis factor alpha (TNF??). The TJ was assessed by transepithelial resistance (TER), permeability, Western blot, PCR, and immunofluorescence. Mucosal samples from patients with ulcerative colitis (UC), Crohn??s disease (CD), and without IBD (normal) were assayed for TJ proteins occludin and claudin-1 by Western blot and a ratio of claudin-1 to occludin (C:O) was calculated.

Results

IEC-18 cells had increased permeability, decreased TER and an increase in claudin-1 with TNF?? treatment. In human specimens, there was a decrease in occludin and an increase in claudin-1 leading to a significant increase in the C:O ratio in diseased UC colon compared to non-diseased UC colon (P < 0.001) and normal colon (P < 0.01). In CD, the C:O ratio was similar in all CD tissue irrespective of disease status.

Conclusions

Treatment of IEC-18 cells with TNF??, a key inflammatory cytokine in IBD, led to a significant increase in claudin-1 expression. There was a significant increase in the C:O ratio in diseased colon in UC compared to the healthy appearing UC colon and normal controls. The C:O ratio was unchanged in CD despite presence or abscence of gross disease. This suggests that there may be an underlying difference in the TJ between UC and CD.     

Correlation of Intestinal Mucosal Healing and Tight Junction Protein Expression in Ulcerative Colitis Patients

Background

The aim of this study was to investigate the relationship between intestinal mucosal healing and tight junction (TJ) protein expression in patients with ulcerative colitis (UC).

反流性食管炎黏膜上皮中紧密连接蛋白及白细胞介素-6的表达

目的 观察反流性食管炎(RE)大鼠食管黏膜中紧密连接蛋白(闭锁蛋白、跨膜蛋白、胞质附着蛋白-1和连接粘附因子-1)的分布和表达,以阐述紧密连接蛋白在RE发病机制中的作用.方法 雄性8周龄Wistar大鼠220只,分成假手术对照组(10只)、酸反流组(70只)、碱反流组(70只)和酸碱混合反流组(70只).动物于术后3、6、9、14 d分批处死,取食管中、下段评估成模率.以透射电镜成像法观察紧密连接形态学的变化.分别用免疫组化法、Western印迹法和RT-PCR法检测白细胞介素(IL)-6、紧密连接蛋白及其mRNA的表达.结果 造模成功率为100%.显微镜下观察发现随着RE的发展,黏膜厚度增加.电镜下可见细胞间隙增宽,桥粒明显减少.模型组IL-6和紧密连接蛋白的表达明显高于对照组,但随着基底层细胞增殖改变的加重,单个细胞间紧密连接蛋白的表达逐渐降低.随着RE病程的发展,IL-6和紧密连接蛋白及其mRNA的表达逐渐增强.结论 紧密连接蛋白高表达参与了RE的发病机制,是RE发生、发展的早期分子事件.其表达可能在RE的病理过程中具有正调节的协同作用,而IL-6是RE发展演进过程中的致炎因子.     

反流性食管炎黏膜上皮中紧密连接蛋白及白细胞介素-6的表达

目的 观察反流性食管炎(RE)大鼠食管黏膜中紧密连接蛋白(闭锁蛋白、跨膜蛋白、胞质附着蛋白-1和连接粘附因子-1)的分布和表达,以阐述紧密连接蛋白在RE发病机制中的作用.方法 雄性8周龄Wistar大鼠220只,分成假手术对照组(10只)、酸反流组(70只)、碱反流组(70只)和酸碱混合反流组(70只).动物于术后3、6、9、14 d分批处死,取食管中、下段评估成模率.以透射电镜成像法观察紧密连接形态学的变化.分别用免疫组化法、Western印迹法和RT-PCR法检测白细胞介素(IL)-6、紧密连接蛋白及其mRNA的表达.结果 造模成功率为100%.显微镜下观察发现随着RE的发展,黏膜厚度增加.电镜下可见细胞间隙增宽,桥粒明显减少.模型组IL-6和紧密连接蛋白的表达明显高于对照组,但随着基底层细胞增殖改变的加重,单个细胞间紧密连接蛋白的表达逐渐降低.随着RE病程的发展,IL-6和紧密连接蛋白及其mRNA的表达逐渐增强.结论 紧密连接蛋白高表达参与了RE的发病机制,是RE发生、发展的早期分子事件.其表达可能在RE的病理过程中具有正调节的协同作用,而IL-6是RE发展演进过程中的致炎因子.     

美沙拉嗪对溃疡性结肠炎患者肠黏膜紧密连接蛋白表达的影响

背景:溃疡性结肠炎(UC)是一种较常见的消化道疾病,其病因和发病机制尚未完全阐明,治疗缺乏特异性方法,导致病情迁延反复。目的:探讨美沙拉嗪治疗对UC肠道紧密连接蛋白的影响。方法:选取2010年12月～2011年6月南京医科大学附属南京医院收治的活动期UC患者30例,给予美沙拉嗪1.0 g tid治疗8周。治疗前后患者行结肠镜检查取活检,以免疫组化法检测治疗前后紧密连接蛋白occludin、ZO-1的表达。结果:美沙拉嗪治疗后UC患者内镜下均取得缓解。免疫组化结果显示,治疗后UC肠黏膜上皮细胞中occludin蛋白(7.20±1.55对1.60±0.55)、ZO-1蛋白表达(6.60±1.26对1.40±0.55)显著高于治疗前,差异均有统计学意义(P<0.05)。结论:美沙拉嗪可能通过上调紧密连接蛋白occludin、ZO-1的表达来保护肠黏膜屏障功能。     

Effect of Acute Stress on Immune Cell Counts and the Expression of Tight Junction Proteins in the Duodenal Mucosa of Rats

Background/AimsDuodenal immune alterations have been reported in a subset of patients with functional dyspepsia (FD). The aim of this study was to investigate the effect of acute stress on immune cell counts and the expression of tight junction proteins in the duodenal mucosa.MethodsTwenty-one male rats were divided into the following three experimental groups: 1) the nonstressed, control group, 2) the 2-hour-stressed group, and 3) the 4-hour-stressed group. Eosinophils, mast cells and CD4⁺ and CD8⁺ T lymphocytes in the duodenal mucosa were counted. The protein and mRNA expressions of occludin and zonula occludens-1 (ZO-1) were examined.ResultsEosinophils, mast cells and CD8⁺ T lymphocyte counts did not differ between the stressed and control groups. The number of CD4⁺ T lymphocytes and the protein and mRNA expressions of occludin and ZO-1 were significantly lower in the 4-hour-stressed group compared with the control group. The plasma adrenocorticotrophic hormone and cortisol levels of the 4-hour-stressed group were significantly higher than those of the control group.ConclusionsAcute stress reduces the number of CD4⁺ T lymphocytes and the expression of tight junction proteins in the duodenal mucosa, which might be associated with the duodenal immune alterations found in a subset of FD patients.