添加特需营养素的营养支持对手术创伤后肠黏膜形态和屏障功能的影响

Influence of ecoimmunonutrition supplement on intestinal mucosa morphology and gut barrier function in rats after operative stress

目的探讨补充益生菌等特需营养素对手术应激后机体肠道屏障功能、上皮紧密连接及微生态的影响。方法SD大鼠70只随机分成对照组、全肠外营养组（TPN组）、普通肠内营养组（EN组）和生态免疫肠内营养组（EEN组）。建立创伤应激模型，接受等氮、等能量营养支持后光镜和电镜下观察肠黏膜形态和紧密连接，比较肠道细菌脏器易位率、肠道菌群数量及肠黏膜occludin蛋白免疫组织化学表达。结果（1）电镜下观察，TPN组肠上皮损伤程度较严重，而EN组和EEN损伤程度较轻，肠上皮紧密连接、微绒毛较完整；光镜下chiu分级，TPN组和EN及EEN组比较差异有统计学意义（P〈0.05）。（2）EEN组和EN组肠道跨膜结合蛋白表达明显优于TPN组，且EEN和EN组间差异也有统计学意义（P〈0.05）。（3）EEN组和EN组肝、肺和肠系膜淋巴结的肠道细菌易位率低于TPN组.差异有统计学意义（P〈0.05）。（4）EEN组和EN组肠道内乳酸杆菌和双歧杆菌数量均高于TPN组，差异有统计学意义（P〈0.05）。结论联合益生菌、肠道黏膜营养素、免疫营养素的营养支持能明显改善肠道微生态环境，维持肠道黏膜屏障和紧密连接，从而防止肠道菌群易位。

Objective To investigate the effects of ecoimmunonutrition supplement on intestinal microecology, epithelial tight junctions, and barrier function in rats with surgical stress. Methods Seventy SD rats after surgical trauma were randomly divided into four groups： （1） placebo group, （2）total parenteral nutrition（TPN） group, （3）enteral nutrition（EN） group and （4）ecoimmunonutrition （EEN） group respectively. Rats received isocaloric and isonitrogenous nutrition. Nutrients were administered via the neck vein and the needle jejunostomy for five days. The homogenated tissues of liver, lung, and mesenteric lymph nodes were cultured to determine the bacterial translocation rate. The transmembrane binding proteins （occludin） was measured by immunohistochemistry. The uhrastructure and morphology of intestinal epithelial tight junctions in the intestine were observed by electron microscope. The feces in cecum was cultured for anaerobic bacterial growth and analysed. Results The amounts of lactobacteria and bifydobacteria in EEN group were significandy higher than those in TPN group （P〈0.05）. The expression levels of occludin in the intestine was significantly higher in EEN group than that in TPN and EN group. Furthermore, the intestinal epithelial tight junction and microvilli of EEN group were more intact compared with those of TPN group. The bacterial translocation rates of liver, lung and mesenteric lymph nodes were significantly lower in EEN and EN group than those in TPN group （P〈0.05）. Conclusion Application of ecoimmunonutrition can protect intestinal mucosal barrier in rats with operative stress, increase the expression of occludin, maintain the gut epithelial tight junction, and eliminate gut bacterial translocation.