复方缓溃乐混悬剂对大鼠溃疡性结肠炎的治疗作用及机制

Effect of Compound Huankuile Suspension on ulcerative colitis in rats and the therapeutic mechanism

目的探讨复方缓溃乐混悬剂对溃疡性结肠炎(ulcerative colitis,UC)大鼠结肠组织细胞因子IL-6、IL-17、IL-10及TGF-β1表达的影响及其治疗UC的作用机制。方法选取50只SPF级Wistar雄性大鼠,TNBS/乙醇复合法建立UC模型并鉴定后,随机数字表法将大鼠随机分为正常组、阴性对照组、复方缓溃乐干预组(HKL组)及5-氨基水杨酸干预组(5-ASA组)。以相应药物干预14 d,进行结肠组织损伤指数(colonic injury index,CMDI)及病理学评分、HE染色观察形态学变化、RT-qPCR和ELISA方法分别检测IL-6、IL-17、IL-10、TGF-β1 mRNA和蛋白质的表达水平。结果与正常组相比,阴性对照组大鼠CMDI及病理学评分分级显著增高(P<0.05);药物干预后,HKL及5-ASA组CMDI及病理学评分分级较阴性对照组均显著降低(P<0.05)。分子实验结果显示:与正常组相比,阴性对照组大鼠IL-6、IL-17、IL-10 mRNA和蛋白质的表达水平均明显上调(P<0.05),TGF-β1 mRNA的表达水平有下调趋势,但差异无统计学意义,而其蛋白质的表达水平明显下调(P<0.05);与阴性对照组相比,HKL组和5-ASA组中IL-6、IL-17 mRNA和蛋白质以及IL-10蛋白质的表达水平均明显下调(P<0.05),TGF-β1 mRNA的表达水平明显上调(P<0.05),而IL-10 mRNA和TGF-β1蛋白质的表达水平只有在HKL组中有明显差异(P<0.05)。HKL组和5-ASA组相比各指标差异均无统计学意义(P>0.05)。结论HKL可以有效改善UC大鼠的一般症状及组织损伤,具有较好的治疗作用,其作用机制可能与促炎因子IL-6、IL-17的下调和抑炎因子TGF-β1的上调有关。

Objective To investigate the effect of Huankuile(HKL)suspension,a compound traditional Chinese herbal medicinal preparation,for treating ulcerative colitis(UC)in rats and explore its therapeutic mechanism.Methods Fifty male Wistar rats were randomized into normal control group,UC model group,HKL suspension intervention group,and 5-amino acid(5-ASA)intervention group.Except for those in the normal control group,all the rats were subjected to colonic enema with 2,4,6-trinitrobenzene sulfonic acid(TNBS)and ethanol to induce UC,followed by drug treatment for 14 d.The colonic injury index(CMDI)and pathological scores of the colon tissues were assessed,and the histopathological changes in the colon was observed with HE staining.The mRNA and protein expression levels of interleukin-6(IL-6),IL-17,IL-10,and transforming growth factor-β1(TGF-β1)in the colon tissues were detected using real-time PCR and ELISA.Results Compared with those in the normal control group,the rats in the UC model group had markedly higher CMDI and pathological scores in the colon tissues(P<0.05),which were significantly reduced by intervention with HKL and 5-ASA(P<0.05).The rats with US showed significantly increased expression of IL-6,IL-17,and IL-10 at both mRNA and protein levels in the colon tissue(P<0.05)without significant changes in TGF-β1 mRNA expression but with significantly decreased TGF-β1 protein expression(P<0.05).Treatment with HKL and 5-ASA obviously lowered the mRNA and protein level of IL-6 and IL-17 and the protein expression of IL-10(P<0.05)and increased the expression level of TGF-β1 mRNA(P<0.05)in the colon tissue of the rats with UC;but only treatment with HKL resulted in significant changes in the expression levels of IL-10 mRNA and TGF-β1 protein in the rats with UC(P<0.05).HKL and 5-ASA showed no significant differences in their therapeutic effects on UC or in their effects on the expressions of the inflammatory factors(P>0.05).Conclusion HKL can effectively improve the symptoms and colonic injury in rats with TNBS-induced UC possibly by down-regulating the pro-inflammatory factors IL-6 and IL-17 and up-regulating the anti-inflammatory factor TGF-β1.