参苓白术散通过调节肠上皮细胞自噬治疗葡聚糖硫酸钠所致小鼠炎症性肠病

Effect of Shenling Baizhu San on Murine Model of IBD Induced by DSS in Mice by Regulating Autophagy

目的:探究参苓白术散对5%葡聚糖硫酸钠(DSS)所致BALB/c小鼠炎症性肠病(IBD)的改善作用与肠上皮细胞自噬的关系。方法:84只BALB/c小鼠,除正常组之外,5%DSS自由饮用7 d诱导急性炎症性肠病,治疗组分别给予参苓白术散高、中、低剂量组(12,6,3 g·kg-1·d-1),美沙拉嗪组(2 g·kg-1·d-1),自噬诱导剂雷帕霉素组(4 mg·kg-1·d-1)灌胃。观察小鼠体质量、粪便性状、隐血便血,计算疾病活动度(DAI)积分;酶联免疫吸附测定(ELISA)检测小鼠血清中炎症因子白细胞介素-8(IL-8),IL-10含量;苏木素-伊红(HE)染色观察结肠组织病理学改变;免疫组化检测肠组织中肿瘤坏死因子-α(TNF-α)和IL-1β的表达;共聚焦显微镜观察肠上皮细胞自噬体形成情况;蛋白免疫印迹法(Western blot)检测自噬相关通路蛋白的水平。结果:与模型组比较,参苓白术散组小鼠隐血,便血,体质量下降,DAI积分,病理改变等均改善;与正常组比较,模型组小鼠血清中IL-10含量显著降低,IL-8含量显著升高(P <0. 01),小鼠肠组织中IL-1β和TNF-α的表达明显升高(P <0. 01),肠上皮细胞自噬体减少,微管轻链蛋白3(LC3)-Ⅱ/LC3-Ⅰ比值含量显著降低(P <0. 01);与模型组比较,参苓白术散可以升高小鼠血清IL-10含量,降低IL-8含量明显(P <0. 05,P <0. 01),明显降低IL-1β和TNF-α的表达(P <0. 05),参芩白术散高剂量组、雷帕霉素及美沙拉嗪组肠上皮细胞自噬体形成显著增多,显著升高LC3Ⅱ/LC3Ⅰ含量。结论:参苓白术散抗DSS诱导的IBD的作用与抑制炎症及调节肠上皮细胞自噬有关。

Objective: To investigate the mechanism of Shenling Baizhu San(SLBZS) in treating dextra sulfate sodium(DSS)-induced inflammatory bowel disease(IBD) mice and its relationship with autophagy.Method: SPF BALB/c mice were randomly divided into control group,model group,mesalazine group,low,medium and high-dose SLBZS groups,and autophagy inducer rapamycin group. The IBD mice were fed with 5%DSS in their drinking water for 7 days,and the control mice received only water. SLBZS groups were given SLBZS at doses of 3,6,12 g·kg-1·d-1,positive group was given mesalazine sustained release granules at the dose of2 g·kg-1·d-1,rapamycin group was given rapamycin at the dose of 4 mg·kg-1·d-1,and control mice was given the same volume of normal saline by gavage. The mice weight,stool occult blood in stool,score of disease activity(DAI),pathological examination of intestinal mucosal lesions integral were observed after 7 days. interleukin(IL)-8 and IL-10 in serum were detected by enzyme-linked immuno sorbent assay(ELISA),vascular tissue samples were prepared for the detection of tumor neorosis factor-(TNF-α) and IL-1β,and transmission electron microscope and Western blot were used to detect the formation of autophagosomes and the level of autophagy.Result: The body mass decrease,the colon length,disease activity scoring,and histological scoring of SLBZS group were better than those of DSS group. Compared with control group,the level of IL-10 decreased,while the level of IL-8 increased obviously(P < 0. 01),IL-1 and TNF-α expressions significantly up-regulated(P < 0. 01),the formation of autophagosome decreased,and LC3-Ⅱ/Ⅰ level down-regulated. Compared with IBD group,SLBZS group showed increase in formation of autophagosome and LC3-Ⅱ/Ⅰ and IL-10,decrease in IL-8(P <0. 05,P < 0. 01),and down-regulation in IL-1 and TNF-α expressions(P < 0. 01). These results were observed in mesalazine group and rapamycin group. Conclusion: Shenling Baizhu San can significantly inhibit the IBD by regulating autophagy and suppressing inflammation.