间歇性断食对老年前期肥胖大鼠肠道菌群及代谢的影响

目的 研究间歇性断食对老年前期肥胖大鼠代谢和肠道菌群的影响.方法 雌性Wistar大鼠经42周高脂高糖饲料饲养造模,根据体质量选取模型鼠进行间歇性断食干预.干预方法为每2周断食72 h,总干预时间18周.干预后进行口服葡萄糖耐量试验、血脂4项检测.收集粪便,通过Illumina高通量测序检测16S rRNA基因V4可变区,运用QIIME及LEfSe分析肠道菌群.结果 间歇性断食组体质量相对于模型对照组显著下降(P<0.01);高密度脂蛋白胆固醇和低密度脂蛋白胆固醇均显著下降(P<0.05);空腹血糖显著上升(P<0.01);葡萄糖耐量测试曲线下面积显著高于模型对照组,糖耐量减退(P<0.05);HE染色显示间歇性断食轻度减少肝脏脂肪变性.肠道菌群结果显示,断食组肠道菌群得到显著改善,具体表现为YS2、RF32、Helicobacteraceae(螺杆菌科)增加,Lactobacillus(乳杆菌属)、Roseburia(罗氏菌属)、Erysipelotrichaceae(韦荣球菌科)、Ralstonia(青枯菌属)、Bradyrhizobiaceae(慢生根瘤菌科)和RF39减少.Spearman相关性分析发现Bradyrhizobiaceae与总胆固醇、高密度脂蛋白胆固醇呈正相关;大鼠体质量与RF39呈负相关.结论 间歇性断食能改善肠道菌群,降低老年前期肥胖大鼠体质量和血脂水平,但对糖代谢有不良影响.

Effect of intermittent fasting on physiology and gut microbiota in presenium rats

Objective To investigate the effect of intermittent fasting on metabolize and gut microbiota in obese presenium rats fed with high-fat-sugar-diet. Methods We fed the Wistar rats with high-fat and high-sugar diet to induce adiposity, and the rats for intermittent fasting were selected base on their body weight. The rats were subjected to fasting for 72 h every 2 weeks for 18 weeks. OGTT test was performed and fasting blood samples and fecal samples were collected for measurement of TC, TG, HDL-C and LDL-C and sequence analysis of fecal 16S rRNA V4 tags using Illumina. Gut microbial community structure was analyzed with QIIME and LEfSe. Results After the intervention, the body weight of the fasting rats was significantly lower than that in high-fat diet group (P<0.01). OGTT results suggested impairment of sugar tolerance in the fasting group, which showed a significantly larger AUC than compared with the high-fat diet group (P<0.05). Intermittent fasting significantly reduced blood HDL-C and LDL-C levels (P<0.05) and partially restored liver steatosis, and improved the gut microbiota by increasing the abundance of YS2, RF32 and Helicobacteraceae and reducing Lactobacillus, Roseburia, Erysipelotrichaceae and Ralstonia. Bradyrhizobiaceae was found to be positively correlated with CHOL and HDL-C, and RF39 was inversely correlated with the weight of the rats. Conclusion Intermittent fasting can decrease the body weight and blood lipid levels and restore normal gut microbiota but can cause impairment of glucose metabolism in obese presenium rats.