双歧杆菌对坏死性小肠结肠炎新生大鼠肠道保护作用的机制  

Protective Effects of Biifdobacterium on intestinal tissue of newborn rats with necrotizing enterocolitis and its regulation

作　　者：苏衡 吕回 周伟 李美雪 黄龙光 李晶 袁伟明 

机构地区：[1]广州市妇女儿童医疗中心新生儿科,510120

出　　处：《中华围产医学杂志》2015年第4期290-295,共6页Chinese Journal of Perinatal Medicine

摘　　要：目的：探讨双歧杆菌防治新生大鼠坏死性小肠结肠炎（necrotizing enterocolitis， NEC）的可能分子机制。方法出生2 h内的新生Sprague-Dawley大鼠75只，随机分为5组，每组15只：（1）NEC模型组：人工喂养＋脂多糖；（2）双歧杆菌干预组：人工喂养＋脂多糖＋双歧杆菌；（3）人工喂养对照组：仅人工喂养；（4）双歧杆菌对照组：人工喂养＋双歧杆菌；（5）母乳喂养对照组：与母鼠同笼鼠乳喂养。脂多糖按30 mg/kg每天灌胃1次，共3 d。双歧杆菌微囊按1×1010菌落形成单位/ml加入到代乳品中灌胃，每天1次。喂养72 h，末次喂养后空腹12 h，断头法处死大鼠。取末段回肠组织光镜下观察形态学改变并对肠道损伤评分，免疫组织化学法检测回肠组织 Toll 样受体（Toll-like receptor，TLR）2、TLR4、核转录因子（nuclear transcription factor，NF）-κB p65蛋白表达。采用Kruskal-Wallis检验、方差分析、校正χ2检验或Fisher精确概率法进行统计学分析。结果 NEC模型组、双歧杆菌干预组、人工喂养对照组、双歧杆菌对照组及母乳喂养对照组的NEC发生比例分别为11/15、4/15、3/15、2/15与0/15；肠道损伤评分分别为（3.37±0.27）、（1.53±0.44）、（1.75±0.37）、（0.92±0.39）与（0.30±0.18）分；TLR2蛋白表达分别为0.35±0.05、0.30±0.03、0.32±0.04、0.30±0.02与0.29±0.03；TLR4蛋白表达分别为0.48±0.05、0.34±0.03、0.36±0.03、0.37±0.04与0.35±0.02；NF-κB p65蛋白表达分别为0.43±0.03、0.29±0.03、0.35±0.02、0.32±0.02与0.30±0.02。5组的NEC发生比例、肠道损伤评分、TLR2、TLR4及NF-κB p65蛋白表达量比较，差异均有统计学意义（χ2、H或F值分别为23.836、70.290、8.803、38.599和75.076，P值均＜0.05），NEC模型组均高于其他4组（P值均＜0.05）。双歧杆菌干预组的NEC发生比例与3个对照组比较，差异均无统计学意义（P值均＞0.05）；肠道损伤评�Objective To discuss the possible molecular mechanisms involved in the protective effects of Biifdobacterium on intestinal tissue of necrotizing enterocolitis （NEC） newborn rats. Methods Seventy-five newborn Sprague-Dawley rats （born within 2 h） were randomly divided into five groups, each group with 15 rats. Group A was the NEC model group, and the rats were fed lipopolysaccharide （LPS） and formula. Group B was＆amp;nbsp;the Biifdobacterium treatment group, and the rats were fed LPS and formula and Biifdobacterium micro-capsule. Group C was the artificial feeding control group, and the rats were fed formula. Group D was the Biifdobacterium control group, and the rats were fed formula and Biifdobacterium micro-capsule. Group E was the breastfeeding control group, and the rats were fed rat breast milk by mothers. LPS 30 mg/kg was administered by gavage once per day for 3 days. Bifidobacterium micro-capsules were given as 1×10^10 colony forming units/ml by gavage with formula once per day. After fed for 72 h and fasted for 12 h, the five groups of rats were killed by decapitation. Morphological changes in the terminal ileum tissue were observed under a light microscope and intestinal injury was scored. The expression of Toll-like receptor （TLR） 2, TLR4, and nuclear transcription factor （NF）-κB p65 was detected by immunohistochemical methods. Kruskal-Wallis test, analysis of variance, corrected Chi-square test and Fisher＇s exact test were used for statistics. Results The morbidity of NEC in group A to E was 11/15, 4/15, 3/15, 2/15 and 0/15, respectively;the intestinal injury score in group A to E was 3.37±0.27, 1.53±0.44, 1.75±0.37, 0.92±0.39 and 0.30±0.18, respectively; the expression level of TLR2 in group A to E was 0.35±0.05, 0.30±0.03, 0.32±0.04, 0.30±0.02 and 0.29±0.03, respectively;the expression level of TLR4 in group A to E was 0.48±0.05, 0.34±0.03, 0.36±0.03, 0.37±0.04 and 0.35±0.02, respectively;the expression level of NF-κB p65 in group A to E was 0.43±0.03, 0.29

关 键 词：小肠结肠炎 坏死性 二裂菌属 TOLL样受体2 Toll样受体4 动物 新生 大鼠 

分 类 号：R722.1[医药卫生—儿科]