青黛对实验性结肠炎抗炎作用的体内外研究

Anti-inflammatory effects of Qingdai powder on experimental ulcerative colitis in vivo and in vitro

目的研究青黛对溃疡性结肠炎(UC)体内、体外炎症模型的抗炎作用。方法大鼠随机分为正常组、模型组、青黛高剂量组、青黛低剂量组,以低浓度TNBS/乙醇溶液灌肠诱导大鼠实验性结肠炎体内炎症模型,连续以青黛高、低剂量混悬液灌胃治疗10 d,酶联免疫吸附法(ELISA)检测血清白细胞介素-1(IL-1)、IL-6、IL-8浓度。以脂多糖(LPS)刺激小鼠巨噬细胞株RAW264.7细胞24h诱导体外炎症模型,以MTT法检测青黛对细胞生存率的影响,以ELISA法研究青黛在直接干预、预防干预2种模式下对细胞培养液IL-6、肿瘤坏死因子-α(TNF-α)表达的影响。结果动物实验:模型组大鼠血清中IL-1、IL-6、IL-8浓度均明显高于空白组(P<0.05),青黛高剂量组血清中IL-1、IL-6、IL-8含量均明显低于模型组(P<0.05),青黛低剂量组血清IL-6、IL-8浓度明显低于模型组(P<0.05)。细胞实验:模型组中IL-6、TNF-α水平较正常组均有明显升高(P<0.05);青黛直接干预时,10μmol/L青黛组细胞培养液IL-6、TNF-α均较模型组有明显下降(P<0.05);青黛预防性干预时,10μmol/L青黛组IL-6明显下降(P<0.05)。结论青黛对溃疡性结肠炎有一定的体内、体外抗炎作用,抗炎机制可能为下调炎症因子的表达。

Objective To study anti-inflammatory effect of Qingdai powder on rat model of ulcerative colitis（UC） and on murine macrophage RAW264.7 cells . Methods Overall SD rats were randomly divided into 4 groups： normal group, model group, Qingdai high-dose group （high-dose group） and Qingdai low-dose group（low-dose group）. Rat model of UC was induced by intracolonical administration of 2, 4, 6-trinitrobenzene sulfonic acid （TNBS）-ethanol solution. Qingdai suspension liquid was administered intragastrically once a day for 10 d. Serum concentration of IL-1 ,IL-6 and IL-8 was tested by ELISA assay. On the other hand, murine macrophage RAW264.7 cells were induced by 10~zg/mL LPS for 24 h to establish an UC inflammatory cell model. Cell viability was detected by MT-F assay to determine the safe range of concentrations. After direct and prophylactic intervention of high- , mid- and low-dose Qingdai suspension on RAW264. 7 eel1 respectively, concentration of IL-6 and TNF-ot in supernatant were tested by ELISA assay. Results Compared with normal group, serum concentration of IL-1 ,IL-6 and IL-8 in model group increased significantly （P 〈 0.05 ）; compared with model group, those of IL-1, IL-6 and IL-8 in high-dose group, and IL-6 and IL-8 in low-dose group decreased significantly（P 〈 0.05）. Compared with normal group, concentration of IL-6 and TNF-α in supernatant increased significantly in model group （P 〈 0.05）. After direct intervention, those of IL-6 and TNF-α in supernatant in 10 μmol/L Qingdai group reduced significantly（P 〈 0.05） compared with model group; while after prophylactic intervention, only IL-6 in 10 μmol/L Qindai group reduced （P 〈 0. 05 ）. Conclusion Effects of anti-inflammation of Qingdai showed both in vivo and in vitro, and the potential mechanism probably was through down-regulating the expression of inflammatory factors.