Department of Food Science and Technology, The University of California, Davis, CA, USA.
FEMS Microbiol Ecol. 2013 Feb;83(2):299-309. doi: 10.1111/j.1574-6941.2012.01475.x. Epub 2012 Sep 17.
Dietary interventions might prevent or reverse age-related declines in health through modification of the activity and composition of the intestinal microbiota. As a first step toward more comprehensive evaluations of single dietary components on healthy aging, 16S rRNA gene amplicon sequencing was applied to determine the structure of the bacterial communities in the ceca of 20-month-old healthy mice fed energy-controlled diets containing 0, 18, or 36% type 2 resistant starch (RS) from high-amylose maize (HAM-RS2). The cecal microbiota of mice fed a diet depleted in RS and containing the readily digestible carbohydrate amylopectin were dominated by bacteria in the Firmicutes phylum and contained low levels of Bacteroidetes and Actinobacteria. In contrast, mice fed diets containing HAM-RS2 were colonized by higher levels of Bacteroidetes and Bifidobacterium, Akkermansia, and Allobaculum species in proportions that were dependent on the concentration of the dietary fiber. The proportions of Bifidobacterium and Akkermansia were positively correlated with mouse feeding responses, gut weight, and expression levels of proglucagon, the precursor of the gut anti-obesity/diabetic hormone GLP-1. This study showed that aging mice harbor a distinct microbiota, which can be modulated by RS and enriched for bacteria that are associated with improved health.
饮食干预可能通过改变肠道微生物群的活性和组成来预防或逆转与年龄相关的健康下降。作为更全面评估单一饮食成分对健康衰老影响的第一步，本研究应用 16S rRNA 基因扩增子测序来确定喂食能量控制饮食的 20 月龄健康小鼠盲肠中细菌群落的结构，这些饮食分别含有 0%、18%或 36%来自高直链淀粉玉米（HAM-RS2）的 2 型抗性淀粉（RS）。缺乏 RS 且含有易消化碳水化合物支链淀粉的饮食会使喂食小鼠的盲肠微生物群主要由厚壁菌门的细菌组成，且拟杆菌门和放线菌门的水平较低。相比之下，喂食 HAM-RS2 饮食的小鼠盲肠中定植了更多的拟杆菌门和双歧杆菌、阿克曼氏菌和 Allobaculum 属细菌，其比例取决于膳食纤维的浓度。双歧杆菌和阿克曼氏菌的比例与小鼠的喂养反应、肠道重量以及前胰高血糖素（肠道抗肥胖/糖尿病激素 GLP-1 的前体）的表达水平呈正相关。本研究表明，衰老小鼠具有独特的微生物群，其可以通过 RS 进行调节，并富集与改善健康相关的细菌。
