肠炎清口服液改善小鼠溃疡性结肠炎肠道黏膜通透性的作用机制

Mechanism of Changyanqing Oral Liquid on Improving Intestinal Mucosal Permeability of Ulcerative Colitis in Mice

摘要:

目的: 建立三硝基苯磺酸(TNBS)诱导的小鼠溃疡性结肠炎模型,研究肠炎清口服液对溃疡性结肠炎小鼠肠黏膜通透性的影响及其可能的作用机制. 方法: 用TNBS对雄性BALB/c小鼠进行造模,将造模后的实验动物随机分成正常组,模型组,柳氮磺吡啶肠溶片组(SASP,0.5 g·kg^-1),肠炎清口服液低、中、高剂量组(0.176,0.352,0.528 g·kg^-1);采用ELISA法检测各组BALB/c小鼠血浆二胺氧化酶(DAO)活性;通过RT-qPCR及Western blot检测方法,观察各组小鼠结肠部位紧密连接相关蛋白水闸蛋白1(claudin-1)、闭锁小带蛋白1(ZO-1)、闭锁蛋白(occludin)的基因表达与蛋白表达. 结果: 肠炎清口服液各剂量组的小鼠血浆中DAO的活性显著低于模型组,差异具有统计学意义(P<0.05);ZO-1,occludin,claudin-1 mRNA在肠炎清口服液高、中、低剂量组小鼠体内表达水平均高于模型组小鼠,且差异具有显著性(P<0.05),且随着给药剂量的增大,claudin-1,ZO-1,occludin mRNA表达水平表现出一定的量效关系;Western blot结果显示,ZO-1及occludin蛋白在肠炎清口服液高、中、低剂量组的表达水平均高于模型组小鼠,且表达差异显著(P<0.05). 结论: 肠炎清口服液在小鼠溃疡性结肠炎中的作用机制与肠道黏膜通透性有密切关系;肠炎清口服液可能是通过调节紧密连接蛋白ZO-1,occludin,claudin-1的表达,从而改善小鼠肠道黏膜通透性.

Abstract:

Objective: To investigate the influence of Changyanqing oral liquid on intestinal mucosal permeability of ulcerative colitis mice and to explore its possible mechanism. Method: The ulcerative colitis (UC) model in BALB/c mice was induced by trinitrobenzene sulfonic acid (TNBS). The UC model mice were randomly divided into normal control group, model control group, salicylazosul fapyridine (SASP) group (0.5 g· kg^-1), Changyanqing low-, moderate- and high-dose group(0.176, 0.352,0.528 g· kg^-1). The plasma diamine oxidase (DAO) activity was detected using ELISA method. The occludin, claudin, zonula occludens(ZO-1) gene expression and protein expression of colon parts were detected using RT-qPCR and Western blot method. Result: The DAO activity in Changyanqing oral liquid of all dosage groups was significantly lower than that in model group with significant difference (P <0.05). The expression levels of occludin, claudin 1, ZO-1 mRNA in Changyanqing of all dosage groups were higher those in model group with significant difference (P<0.05). Better concentration-response relationship was shown between the level claudin 1, ZO-1, occludin mRNA expression and drug delivery dosage. The expression level of ZO-1 and occludin proteins in the intestine of all Changyanqing dosage groups were higher than that those in model group with significant difference (P<0.05). Conclusion: The mechanism of Changyanqing oral liquid in treating ulcerative colitis may be achieved by improving the intestinal mucosal permeability, which is relevant to regulating the expression level of occludin, claudin and ZO-1.