参苓白术散对克罗恩病大鼠肠黏膜屏障的影响

Effects of Shenling Baizhu Powder on intestinal mucosal barrier in rats with Crohn's disease

目的观察参苓白术散对克罗恩病(Crohn's disease,CD)大鼠肠黏膜屏障的影响。方法60只SD大鼠随机均分为空白组、模型组、美沙拉秦组(0.21 g·kg^(-1)·d^(-1))及参苓白术散高、中、低剂量组(5.88、11.76、23.52 g·kg^(-1)·d^(-1))。采用2,4,6-三硝基苯磺酸(2,4,6-three nitrobenzene sulfonic acid,TNBS)灌肠液制作CD模型。给药各组予以相应药物灌胃,空白组、模型组予以等剂量灭菌注射用水。监测每组大鼠在用药期间的体征变化,14 d后进行结肠黏膜损伤指数(colon injury morphology index,CMDI)评分、组织病理学观察,qPCR检测闭合蛋白(Occludin)、闭锁连接蛋白-1(zonulaoccludens-1,ZO-1)及E-钙黏蛋白(E-cadherin)的mRNA表达水平,Western blot法检测各组大鼠结肠组织中Occludin、ZO-1、E-cadherin蛋白表达水平。结果与空白组对比,模型组大鼠体质量明显下降,活动能力减弱,普遍出现稀便情况,少量大鼠出现便血及黏液便情况;CMDI评分显著升高(P<0.01);黏膜可见上皮坏死脱落,内部腺体坏死,大量炎性细胞浸润;Occludin、ZO-1、E-cadherin的mRNA水平及蛋白表达均明显降低(P<0.01)。与模型组对比,美沙拉秦组及参苓白术散低、中、高剂量组大鼠体质量不同程度升高,大便基本成形,个别大鼠有少量便血,无明显黏液便;美沙拉秦组及参苓白术散高、中剂量组CMDI评分均降低(P<0.01),结肠黏膜损伤明显减轻;参苓白术散高剂量组Occludin、ZO-1、E-cadherin的mRNA水平及蛋白表达显著升高(P<0.01或P<0.05)。结论参苓白术散可能通过调控Occludin、ZO-1及E-cadherin mRNA及蛋白的表达,促进CD大鼠结肠黏膜屏障功能的修复,有效缓解CD大鼠肠黏膜屏障损伤。

Objective To observe the effects of Shenling Baizhu Powder(SLBZP)on the intestinal mucosal barrier in rats with Crohn's disease(CD).Methods Sixty SD rats were randomized into blank group,model group,mesalamine group(0.21 g·kg^(-1)·d^(-1)),and high-,medium-,and low-dose SLBZP groups(5.88,11.76,23.52 g·kg^(-1)·d^(-1)).CD model was established by 2,4,6-trinitrobenzene sulfonic acid(TNBS)enema.Each treatment group was given the corresponding drug by gavage,and blank group and model group were given equal doses of sterilized water for injection.The changes in the signs of each group during the medication period were monitored.After 14 days,the colon injury morphology index(CMDI)score and histopathological observation were performed,qPCR was used to determine the mRNA expression levels of occludin,zonulaoccludens-1(ZO-1)and E-cadherin.Western blot was used to determine the expression levels of occludin,ZO-1 and E-cadherin proteins in the colon tissues of rats in each group.Results Compared with blank group,rats in model group showed significant decrease in body mass,reduced mobility,and generally loose stools,with a small number of rats showing blood and mucus stools.The CMDI score was significantly higher(P<0.01).Epithelial necrosis and detachment,necrosis of internal glands,and infiltration of a large number of inflammatory cells were seen in the mucosa.The mRNA levels and protein expressions of occludin,ZO-1,and E-cadherin were significantly reduced(P<0.01).Compared with model group,the body mass of rats in mesalazine group and the low-,middle-and high-dose SLBZP groups increased to different degrees,and the stools were basically formed.Some rats had mild hematochezia and no obvious mucus stools.The CMDI scores in mesalazine group and the high-and middle-dose groups decreased(P<0.01),and the injury of colon mucosa was obviously alleviated.The mRNA levels and protein expressions of occludin,ZO-1,and E-cadherin in the high-dose SLBZP group were significantly higher(P<0.01 or P<0.05).Conclusion SLBZP may promote the repair of colonic mucosal barrier function in CD rats by increasing mRNA and protein expressions of occludin,ZO-1 and E-cadherin,so as to effectively alleviate the intestinal mucosal barrier injury in rats with Crohn's disease.