Yu Danxia, Yang Yaohua, Long Jirong, Xu Wanghong, Cai Qiuyin, Wu Jie, Cai Hui, Zheng Wei, Shu Xiao-Ou
Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.
Curr Dev Nutr. 2021 Apr 2;5(4):nzab026. doi: 10.1093/cdn/nzab026. eCollection 2021 Apr.
Diet is known to affect human gut microbiome composition; yet, how diet affects gut microbiome functionality remains unclear.
We compared the diversity and abundance/presence of fecal microbiome metabolic pathways among individuals according to their long-term diet quality.
In 2 longitudinal cohorts, we assessed participants' usual diets via repeated surveys during 1996-2011 and collected a stool sample in 2015-2018. Participants who maintained a healthy or unhealthy diet (i.e., stayed in the highest or lowest quintile of a healthy diet score throughout follow-up) were selected. Participants were excluded if they reported a history of cancer, cardiovascular disease, diabetes, or hypertension; had diarrhea or constipation in the last 7 d; or used antibiotics in the last 6 mo before stool collection. Functional profiling of shotgun metagenomics was performed using HUMAnN2. Associations of dietary variables and 420 microbial metabolic pathways were evaluated via multivariable-adjusted linear or logistic regression models.
We included 144 adults (mean age = 64 y; 55% female); 66 had an unhealthy diet and 78 maintained a healthy diet. The healthy diet group had higher Shannon α-diversity indexes of microbial gene families and metabolic pathways (both < 0.02), whereas β-diversity, as evaluated by Bray-Curtis distance, did not differ between groups (both > 0.50). At < 0.01 [false discovery rate (FDR) <0.15], the healthy diet group showed enriched pathways for vitamin and carrier biosynthesis (e.g., tetrahydrofolate, acetyl-CoA, and l-methionine) and tricarboxylic acid (TCA) cycle, and increased degradation (or reduced biosynthesis) of certain sugars [e.g., cytidine monophosphate (CMP)-legionaminate, deoxythymidine diphosphate (dTDP)-l-rhamnose, and sucrose], nucleotides, 4-aminobutanoate, methylglyoxal, sulfate, and aromatic compounds (e.g., catechol and toluene). Meanwhile, several food groups were associated with the CMP-legionaminate biosynthesis pathway at FDR <0.05.
In a small longitudinal study of generally healthy, older Chinese adults, we found long-term healthy eating was associated with increased α-diversity of microbial gene families and metabolic pathways and altered symbiotic functions relevant to human nutrition and health.
已知饮食会影响人体肠道微生物群的组成；然而，饮食如何影响肠道微生物群的功能仍不清楚。
我们根据个体的长期饮食质量，比较了粪便微生物群代谢途径的多样性和丰度/存在情况。
在2个纵向队列中，我们通过1996 - 2011年期间的重复调查评估参与者的日常饮食，并在2015 - 2018年收集粪便样本。选择保持健康或不健康饮食的参与者（即在整个随访期间处于健康饮食评分的最高或最低五分位数）。如果参与者报告有癌症、心血管疾病、糖尿病或高血压病史；在过去7天内有腹泻或便秘；或在收集粪便前的最后6个月内使用过抗生素，则将其排除。使用HUMAnN2对鸟枪法宏基因组学进行功能分析。通过多变量调整的线性或逻辑回归模型评估饮食变量与420种微生物代谢途径的关联。
我们纳入了144名成年人（平均年龄 = 64岁；55%为女性）；66人饮食不健康，78人保持健康饮食。健康饮食组微生物基因家族和代谢途径的香农α多样性指数较高（均 < 0.02），而通过布雷 - 柯蒂斯距离评估的β多样性在两组之间没有差异（均 > 0.50）。在 < 0.01 [错误发现率（FDR）< 0.15]时，健康饮食组显示维生素和载体生物合成（如四氢叶酸、乙酰辅酶A和L - 甲硫氨酸）以及三羧酸（TCA）循环的途径丰富，某些糖类[如胞苷单磷酸（CMP） - 军团菌酸、脱氧胸苷二磷酸（dTDP） - L - 鼠李糖和蔗糖]、核苷酸、4 - 氨基丁酸、甲基乙二醛、硫酸盐和芳香族化合物（如儿茶酚和甲苯）的降解增加（或生物合成减少）。同时，在FDR < 0.05时，几个食物组与CMP - 军团菌酸生物合成途径相关。
在一项针对一般健康的中国老年成年人的小型纵向研究中，我们发现长期健康饮食与微生物基因家族和代谢途径的α多样性增加以及与人类营养和健康相关的共生功能改变有关。
