苦参碱调节IL-6/STAT3信号通路对炎症性肠病大鼠肠黏膜损伤的影响

Effect of Matrine on Intestinal Mucosal Injury in Rats with Inflammatory Bowel Disease by Regulating IL-6/STAT3 Signaling Pathway

【目的】观察苦参碱调节白细胞介素6(IL-6)/信号转导子和转录激活子3(STAT3)信号通路对炎症性肠病(IBD)大鼠肠黏膜损伤的影响。【方法】以三硝基苯磺酸(TNBS)结肠灌注法构建IBD大鼠模型,随机分为模型组,苦参碱低、高剂量组,苦参碱高剂量+colivelin(STAT3激活剂)组,每组10只;再选10只大鼠结肠灌注等体积生理盐水作为正常组。经苦参碱和colivelin处理后,检测各组大鼠体质量和疾病活动指数(DAI),采用苏木素-伊红(HE)染色法检测大鼠结肠黏膜组织病理学变化,透射电镜观察大鼠结肠黏膜组织超微结构变化,采用酶联免疫吸附分析(ELISA)和比色法分别检测大鼠血清和结肠黏膜组织白细胞介素6(IL-6)、C-反应蛋白(CRP),超氧化物歧化酶(SOD)、丙二醛(MDA)水平,采用蛋白免疫印迹(Western Blot)法检测大鼠结肠黏膜组织IL-6/STAT3通路相关蛋白表达。【结果】与正常组比较,模型组大鼠结肠黏膜组织发生严重病理损伤且其超微结构受损明显,DAI,结肠黏膜组织病理评分,血清和结肠黏膜组织CRP、IL-6、MDA水平,结肠黏膜组织IL-6蛋白表达及p-STAT3/STAT3比值显著升高(P<0.05),体质量、血清和结肠黏膜组织SOD水平显著降低(P<0.05);与模型组比较,苦参碱低、高剂量组大鼠结肠黏膜组织病理损伤及其超微结构受损均减轻,DAI,结肠黏膜组织病理评分,血清和结肠黏膜组织CRP、IL-6、MDA水平,结肠黏膜组织IL-6蛋白表达及p-STAT3/STAT3比值均降低(P<0.05),体质量、血清和结肠黏膜组织SOD水平均升高(P<0.05),且呈剂量依赖性;与苦参碱高剂量组比较,苦参碱高剂量+colivelin组大鼠结肠黏膜组织病理损伤及其超微结构受损加重,DAI,结肠黏膜组织病理评分,血清和结肠黏膜组织CRP、IL-6、MDA水平,结肠黏膜组织IL-6蛋白表达及p-STAT3/STAT3比值升高(P<0.05),体质量、血清和结肠黏膜组织SOD水平降低(P<0.05)。【结论】苦参碱可通过阻止IL-6/STAT3信号通路激活降低炎症及氧化应激水平,进而减轻IBD大鼠肠黏膜损伤。

To observe the effect of matrine on intestinal mucosal injury in rats with inflammatory bowel disease(IBD)by regulating interleukin 6(IL-6)/signal transducer and activator of transcription 3(STAT3)signaling pathway.Methods IBD model rats were constructed by colon perfusion of trinitrobenzene sulfonic acid(TNBS)method,and randomly divided into model group,matrine low-and high-dose groups,and matrine high-dose+colivelin(STAT3 activator)group,with 10 rats in each group.Another 10 rats were selected for colon perfusion with equal volume of normal saline as the normal group.After treatment with matrine and colivelin,the body mass and disease activity index(DAI)of rats in each group were detected.The histopathological changes of colonic mucosa in rats were detected by hematoxylin-eosin(HE)staining.The ultrastructural changes of colonic mucosa in rats were observed by transmission electron microscopy.The levels of interleukin-6(IL-6),C-reactive protein(CRP),and superoxide dismutase(SOD),malondialdehyde(MDA)in serum and colonic mucosa of rats in each group were measured by enzyme-linked immunosorbent assay(ELISA)and colorimetry,respectively.The expression of IL-6/STAT3 pathway-related proteins in rat colonic mucosa was detected by Western Blot.Results Compared with the normal group,the colonic mucosal tissue of rats in the model group had severe pathological damage and obvious ultrastructural damage,DAI,colonic mucosal histopathological score,serum and colonic mucosal tissue CRP,IL-6,MDA levels,and IL-6 protein expression and p-STAT3/STAT3 levels in colonic mucosal tissue were significantly increased(P<0.05),and body mass,serum and colonic mucosal tissue SOD level were significantly decreased(P<0.05).Compared with the model group,the pathological damage and ultrastructural damage of colonic mucosa in the low-and high-dose of matrine groups were alleviated,DAI,pathological score of colonic mucosa,CRP,IL-6,MDA levels in serum and colonic mucosa,IL-6 protein expression and p-STAT3/STAT3 ratio in colonic mucosa were decreased(P<0.05),and body mass,SOD level in serum and colonic mucosa were increased(P<0.05),in a dose-dependent manner.Compared with the matrine high-dose group,the pathological damage and ultrastructural damage of colonic mucosa in the matrine high-dose+colivelin group were aggravated,DAI,colonic mucosa histopathological score,serum and colonic mucosa CRP,IL-6,MDA levels,colonic mucosa IL-6 protein expression and p-STAT3/STAT3 ratio were increased(P<0.05),body mass,serum and colonic mucosa SOD level were decreased(P<0.05).Conclusion Matrine can reduce the level of inflammation and oxidative stress by preventing the activation of IL-6/STAT3 signal pathway,thereby reducing intestinal mucosal injury in IBD rats.