单形拟杆菌减轻组织脂质沉积及内质网应激改善小鼠葡萄糖代谢  

Bacteroides uniformis supplementation improves glucose homeostasis by alleviating lipid accumulation and endoplasmic reticulum stress in liver/muscle in chow-diet mice

作　　者：赵少倩 刘文[1] 石娟[1] 王计秋[1] 刘瑞欣[1] 洪洁[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院内分泌科上海市内分泌代谢病研究所,上海200025

出　　处：《诊断学理论与实践》2016年第3期263-267,共5页Journal of Diagnostics Concepts & Practice

基　　金：上海市卫生系统优秀学科带头人培养计划(XBR201307)

摘　　要：目的:探讨潜在益生菌——单形拟杆菌(Bacteroides uniformis,B.uniformis)对糖脂代谢正常个体的影响,为代谢正常人群应用获益提供前期证据。方法:采用正常饮食野生型C57BL6/J雄性小鼠为研究对象,分别给予B.uniformis(2×108CFUs)(实验组)和无菌磷酸缓冲盐溶液(phosphate buffer saline,PBS)灌胃(对照组)5周,观察2组小鼠的体重、体脂、糖代谢等代谢表型变化,通过检测糖代谢相关基因m RNA的表达水平,探讨过程中可能涉及的分子机制。结果:与对照组相比,B.uniformis组小鼠的体重及体脂含量未见明显改善,但实验组小鼠腹腔注射葡萄糖耐量实验结果显示其糖耐量明显改善;此外,经B.uniformis处理后,小鼠肝脏、肌肉组织的脂质合成基因SREBP1C、ACC、脂肪酸转运基因CD36及内质网应激相关基因CHOP、BIP、PDI、XBP1、PERK的m RNA表达水平显著降低。结论:B.uniformis可通过减少血糖调节器官肝脏和肌肉组织的脂质异位沉积和内质网应激,从而改善小鼠的糖代谢表型。研究结果为代谢正常个体早期应用益生菌预防代谢性疾病提供了前期动物试验证据,为代谢性疾病的早期预防提供了一种可选策略。Objective： To investigate the metabolic benefits of Bacteroides uniformis, a potential probiotic, in healthy subjects, and to provide evidence for benefit from probiotic supplementation. Methods： Chow-diet fed C57BL6/J mice were treated with B.uniformis 2×108colony-forming units（CFUs）/200 μL by daily gavage for five weeks, while their counterparts were treated with sterile PBS. Expressions of relative genes involved in lipid biosynthesis, fatty acid import and endoplasmic reticulum stress（ER stress） in insulin-responsive tissues（liver and muscle） were determined by real-time PCR. Results： B.uniformis supplementation significantly improved glucose tolerance in chow-diet fed mice（P0.05） without affecting body weight gain and fat mass. The relative m RNA expression of lipid biosynthesis gene SREBP1 C, fatty acid transport regulator CD36 and ER stress-related genes were decreased after B.uniformis supplementation（P 0.05）.Conclusions： B.uniformis supplementation ameliorates ectopic lipid accumulation and ER stress in liver and muscle,thereby improving glucose homeostasis of chow-diet fed mice. These results provide the possible mechanism of B.uniformis′s metabolic benefits, which provides new evidence for the supplementation of probiotic to healthy subjects and suggests a new strategy to prevent the development of metabolic disorders at earlier stage.

关 键 词：Bacteroidesuniformis 葡萄糖耐量 异位脂质沉积 内质网应激 

分 类 号：R587.1[医药卫生—内分泌]