松三糖对溃疡性结肠炎的作用

Effects of melezitose on ulcerative colitis mice

目的通过葡聚糖硫酸钠(DSS)诱导建立溃疡性结肠炎(UC)小鼠模型,探讨松三糖(MELE)对UC小鼠的作用机制。方法将48只SPF级雄性c57BL/6小鼠随机分为正常组(0.9%NaCl)、模型组(0.9%NaCl)、对照组(100 mg·kg^(-1)美拉沙秦)和低、中、高剂量实验组(20、40、80 mg·kg^(-1)松三糖溶液)。通过给予3%DSS溶液代替饮用水诱导UC模型,并进行疾病活动指数(DAI)评估。用酶联免疫吸附试验法检测血清中白细胞介素-1β(IL-1β)、IL-6、IL-10和肿瘤坏死因子-α(TNF-α)水平,用蛋白质印迹法检测主要组织相容性复合体Ⅱ(MHCⅡ)和表面抗原分化簇4受体(CD4)蛋白的表达水平。结果中、高剂量实验组和模型组、正常组的血清中IL-1β水平分别为(82.15±13.66)、(75.56±11.07)、(118.20±19.31)和(23.47±4.72)pg·mL^(-1),IL-6水平分别为(71.54±16.48)、(58.57±15.62)、(140.60±5.76)和(30.33±4.15)pg·mL^(-1),IL-10水平分别为(48.64±5.60)、(52.65±7.99)、(27.10±4.91)和(61.90±10.44)pg·mL^(-1),TNF-α水平分别为(70.33±8.51)、(66.55±8.12)、(90.88±4.90)和(34.18±4.15)pg·mL^(-1),MHCⅡ蛋白相对表达水平分别为0.34±0.04、0.15±0.06、0.08±0.05和0.53±0.59,CD4蛋白相对表达水平分别为0.79±0.08、0.92±0.12、0.99±0.11和0.54±0.14。中、高剂量实验组和正常组的上述指标与模型组比较,在统计学上差异均有统计学意义(P<0.05,P<0.01)。结论松三糖能够有效改善UC小鼠的症状,其作用机制可能是通过下调MHCⅡ蛋白和上调CD4蛋白表达来激活T细胞信号通路,从而发挥抗炎作用。

Objective To investigate the mechanism of melezitose(MELE)on ulcerative colitis(UC)by structing a mouse model of ulcerative colitis(UC)induced by dextran sodium sulfate(DSS).Methods Forty-eight SPF grade male c57BL/6 mice were randomly divided into normal group(0.9%NaCl),model group(0.9%NaCl),control group(100 mg·kg^(-1)mesalazine)and experimental-L,-M,-H groups(20,40,80 mg·kg^(-1)melezitose solution).The UC model was induced by giving 3%DSS solution instead of drinking water,and the disease activity index(DAI)was evaluated.Serum levels of interleukin-1β(IL-1β),IL-6,IL-10 and tumor necrosis factorα(TNF-α)were detected by enzyme linked immunosorbent assay.The expression levels of major histocompatibility complexⅡ(MHCⅡ)and cluster of differentiation 4 receptors(CD4)protein were detected by Western blot.Results The levels of IL-1β in serum in the experimental-M,-H groups,model group and normal group were(82.15±13.66),(75.56±11.07),(118.20±19.31)and(23.47±4.72)pg·mL^(-1);serum IL-6 levels were(71.54±16.48),(58.57±15.62),(140.60±5.76)and(30.33±4.15)pg·mL^(-1);serum IL-10 levels were(48.64±5.60),(52.65±7.99),(27.10±4.91)and(61.90±10.44)pg·mL^(-1);serum TNF-αlevels were(70.33±8.51),(66.55±8.12),(90.88±4.90)and(34.18±4.15)pg·mL^(-1);the relative expression levels of MHCⅡprotein were 0.34±0.04,0.15±0.06,0.08±0.05 and 0.53±0.59;the relative expression levels of CD4 protein were 0.79±0.08,0.92±0.12,0.99±0.11 and 0.54±0.14,respectively.Compared with the model group,the above indexes in the experimental-M,-H groups showed statistically significant differences(P<0.05,P<0.01).Conclusion Melezitose could effectively improve the symptoms of UC mice;the mechanism may be through down-regulating MHCⅡprotein and up-regulating CD4 protein to activate T cell signal pathway to play an anti-inflammatory effect.