Dietary intervention impact on gut microbial gene richness based on SOLiD next generation sequencing technology. Dietary intervention impact on gut microbial gene richness

Complex gene-environment interactions are considered important in the development of obesity. The composition of the gut microbiota can determine the efficacy of energy harvest from food and changes in dietary composition have been associated with changes in the composition of gut microbial populations. The capacity to explore microbiota composition was dramatically improved by the development of metagenomic approaches, which have already allowed production of the first human gut microbial gene catalogue and stratifying individuals by their gut genomic profile into different enterotypes, but the analyses were carried out mainly in non-intervention settings. To investigate the temporal relationships between food intake, gut microbiota and metabolic and inflammatory phenotypes, we conducted diet-induced weight loss and weight stabilisation interventions in a study sample of 38 obese and 11 overweight individuals. Here we report that individuals with reduced microbial gene richness (40%) present more pronounced dys-metabolism and low-grade inflammation, as observed concomitantly in the accompanying paper. Dietary intervention improves low gene richness and clinical phenotypes, but appears to be less efficient for inflammation variables in individuals with lower gene richness, which thus may have predictive potential for the efficacy of intervention.

复杂的基因-环境交互作用被认为在肥胖的发生发展中具有重要意义。肠道微生物群（gut microbiota）的组成可决定机体从食物中获取能量的效率，而膳食结构的变化也与肠道微生物种群组成的改变密切相关。宏基因组学方法（metagenomic approaches）的发展极大提升了解析微生物群组成的能力，该技术已助力完成首个人类肠道微生物基因目录的构建，并可根据肠道基因组特征将个体划分为不同肠型（enterotypes），但此前的相关分析主要集中于非干预场景。为探究食物摄入、肠道微生物群与代谢及炎症表型之间的时序关联，本研究对包含38名肥胖者与11名超重者的研究队列开展了饮食诱导的减重与体重稳定干预。本研究结果显示，微生物基因丰度降低40%的个体，其代谢异常与低度炎症表现更为显著，这一发现与同期发表的配套论文中的观测结果一致。饮食干预可改善低基因丰度状态与临床表型，但对于基因丰度较低的个体，其在炎症指标改善方面的效果似乎欠佳，这提示微生物基因丰度或许可作为预测干预有效性的潜在标志物。