【作者】 洪慧杰；

【导师】 侯恒；

【作者基本信息】 山西医科大学 ， 消化内科， 2011， 硕士

【摘要】 目的：观察嗜酸乳杆菌联合美沙拉嗪对小鼠溃疡性结肠炎(UC)的治疗作用,并探讨其可能的作用机制。方法：2.5% DSS 7天建立急性UC动物模型。将70只BALB/c小鼠随机分为7组：分别为正常组、模型组、阴性对照(生理盐水,NS)组、美沙拉嗪组、嗜酸乳杆菌低(106CFU/ml)、高(108CFU/ml)剂量组、嗜酸乳杆菌联合美沙拉嗪组,每组10只。正常组自由饮用双重蒸馏水,其余六组小鼠自由饮用2.5%DSS 7天建立急性UC动物模型。从造模前2天开始,阴性组、美沙拉嗪组、嗜酸乳杆菌低、高剂量组、嗜酸乳杆菌联合美沙拉嗪组分别给予无菌生理盐水、美沙拉嗪(30.25mg/ml)、嗜酸乳杆菌菌液1×106CFU/ml、1×108CFU/ml、嗜酸乳杆菌菌液1×108CFU/ml联合美沙拉嗪(30.25mg/ml)灌胃,每次0.2ml,一天2次。实验期间每天记录小鼠体重、大便性状与隐血情况。造模第八天上午折颈法处死小鼠,取出结肠,取部分远端结肠组织甲醛固定、石蜡包埋、切片,HE染色。观察指标包括：疾病活动指数(DAI)、结肠粘膜肉眼改变及病理组织学积分；采用免疫组化SABC法检测热休克蛋白70(HSP70)和c-Jun氨基末端激酶(JNK)的表达量。结果：1.饮用DSS后,随天数增加UC小鼠DAI积分不断增高,嗜酸乳杆菌可降低DAI积分。嗜酸乳杆菌联合美沙拉嗪组DAI积分最低。与模型组、美沙拉嗪组、嗜酸乳杆菌低、高剂量组比较均有统计学意义(p<0.05)。2.各组UC小鼠组织学评分均高于正常组(p<0.05),美沙拉嗪组、嗜酸乳杆菌组、嗜酸乳杆菌联合美沙拉嗪组组织学评分降低,与模型和阴性对照组比较差异有统计学意义(P<0.05)。3.UC小鼠结肠粘膜HSP70表达量较正常组低(p<0.05),嗜酸乳杆菌和美沙拉嗪治疗后,能增加其表达量,差异有统计学意义(p<0.05)。JNK在正常组微量表达,实验组表达增加,应用嗜酸乳杆菌和美沙拉嗪治疗后,能抑制其表达,差异有统计学意义(P<0.05)。结论：1.嗜酸乳杆菌和美沙拉嗪对小鼠溃疡性结肠炎都有治疗作用,且二者疗效相当；两药联合应用效果最佳。2.嗜酸乳杆菌能有效治疗急性期UC小鼠,其机制可能与抑制JNK的激活,增加结肠粘膜HSP70的表达有关。更多还原

【Abstract】 Objective:To investigate the effect of probiotics-lactobacillus Combined with mesalazine on ulcerative colitis in mice to find its possible mechanism of treating uc.Methods:Experimental colitis was induced by drinking 2.5% dextran sulfate sodium (DSS) freely for 7 consecutive days. Seventy mice were randomly divided into seven groups as follows:normal control group, model control group, negative control group(normal saline,NS), mesalazine group, low-dose (106 CFU/ml),high-dose (108 CFU/ml) lactobacillus acidophilus group and lactobacillus acidophilus combined with mesalazine group. The normal group-mice were only fed with distilled water. Experimental group was induced by drink 2.5% dextran sulfate sodium (DSS, MW:36000-50000) freely for 7 consecutive days. Before two days, each experimental group of the mice was given normal saline(NS), mesalazine (30.25mg/ml), lactobacillus acidophilus (1.0×106CFU/ml), lactobacillus acidophilus (1.0x108CFU/ml), lactobacillus acidophilus (1.0x108CFU/ml) and mesalazine (30.25mg/ml) respectively. The model group was given empty needle to insert stomach.During the experiment, daily weight,stool trait and occult blood were recorded. After 8 days, the mice of each group were sacrificed. The distal colon were obtained respectively.Some colon specimens for maldehyde fixed, were embedded in paraffin and stained with hematoxylin-eosin (H&E), and the conditions of the mice were observed. Disease activity index(DAI) and histological injury scores were used to assess the efficacy of intervention groups; HSP70 and JNK expression in colonic mucosa were measured by immunohistochemistry(IHC).Results:1. probiotics could significantly reduce the DAI and colonic histological scores of experimental mice;2. The expression of JNK at protein level was decreased(P<0.05) in low-dose (106 CFU/ml),high-dose (108 CFU/ml) lactobacillus acidophilus group and lactobacillus acidophilus Combined with mesalazine group, compared with model control and negative control groups; The expression of HSP70 was increased, which was most evidenced in lactobacillus acidophilus Combined with mesalazine group.Conclusion:1. Both Lactobacillus acidophilus and mesalazine were effective on trearment of uc. Efficiency of Lactobacillus acidophilus is similar to that of mesalazine. lactobacillus acidophilus Combined with mesalazine is the best. 2. Lactobacillus had therapeutic effects on the acute UC mice. Its mechanism may be related to the inhibition of the activation of JNK and up-regulation of HSP70.更多还原