School of Public Health, Capital Medical University, Beijing, China.
Am J Clin Nutr. 2021 Aug 2;114(2):429-440. doi: 10.1093/ajcn/nqab078.
Diet, the gut microbiota, and microRNAs (miRNAs) have been recognized as factors possibly influencing the pathogenesis of Alzheimer's disease. However, the combined role of diet, the gut microbiota, and miRNAs in mild cognitive impairment (MCI) has not been extensively investigated.
To examine the associations among diet quality, the gut microbiota, miRNAs, and risks of MCI in middle-aged and elderly Chinese population.
Participants were drawn from the Effects and Mechanism Investigation of Cholesterol and Oxysterol on Alzheimer's disease (EMCOA) study. We included 2239 participants who completed comprehensive cognitive tests and dietary surveys at baseline and follow-up. Chinese Dietary Guidelines Index 2018 (CDGI-2018), Energy-Adjusted Dietary Inflammatory Index (E-DII) and Healthy Lifestyle Score (HLS) values were calculated based on data from a standard questionnaire. Changes of gut microbiota and serum miRNA expression were detected in 75 MCI and 52 healthy participants. The receiver operating characteristic curve was performed based on a logistic regression model distinguishing patients with MCI from healthy controls.
Higher CDGI-2018 (RR, 0.75; 95% CI: 0.58-0.98) and HLS (RR, 0.54; 95% CI: 0.34-0.84) values and lower E-DII (RR, 1.46; 95% CI: 1.14-1.87) values were significantly associated with a lower risk of MCI. Lower microbial diversity and abundance of Faecalibacterium, unidentified Ruminococcaceae, and Alistipes were found in MCI participants compared with healthy controls. The abundance of ProteobacteriaandGammaproteobacteria was higher in MCI participants and was correlated with hsa-let-7g-5p, hsa-miR-107, and hsa-miR-186-3p. The predictive signatures of diet quality scores, differential gut microbiota, and serum miRNAs had good performance on distinguishing MCI participants from healthy individuals (AUC = 0.91).
A better diet quality is associated with a lower risk of MCI, which may be mediated by the microbiota composition and miRNA expression. These findings suggest that diet, the gut microbiota, and miRNAs may serve as a combinatorial biomarker to identify MCI patients and provide new insight for the diagnosis and prevention of MCI. This study was registered at the Chinese Clinical Trial Registry as ChiCTROOC-17011882.
饮食、肠道微生物群和 microRNAs（miRNAs）已被认为是可能影响阿尔茨海默病发病机制的因素。然而，饮食、肠道微生物群和 miRNAs 在轻度认知障碍（MCI）中的综合作用尚未得到广泛研究。
研究中国中老年人饮食质量、肠道微生物群、miRNAs 与 MCI 风险之间的关联。
参与者来自胆固醇和氧化固醇对阿尔茨海默病影响及机制研究（EMCOA）。我们纳入了 2239 名参与者，他们在基线和随访时完成了全面的认知测试和饮食调查。根据标准问卷中的数据，计算了 2018 年中国膳食指南指数（CDGI-2018）、能量调整的饮食炎症指数（E-DII）和健康生活方式评分（HLS）值。在 75 名 MCI 患者和 52 名健康对照者中检测了肠道微生物群和血清 miRNA 表达的变化。根据区分 MCI 患者和健康对照者的逻辑回归模型，进行了受试者工作特征曲线分析。
较高的 CDGI-2018（RR，0.75；95%CI：0.58-0.98）和 HLS（RR，0.54；95%CI：0.34-0.84）值和较低的 E-DII（RR，1.46；95%CI：1.14-1.87）值与 MCI 风险降低显著相关。与健康对照组相比，MCI 患者的微生物多样性和 Faecalibacterium、未鉴定的 Ruminococcaceae 和 Alistipes 的丰度较低。MCI 患者的 Proteobacteria 和 Gamma-proteobacteria 的丰度较高，与 hsa-let-7g-5p、hsa-miR-107 和 hsa-miR-186-3p 相关。饮食质量评分、差异肠道微生物群和血清 miRNAs 的预测特征在区分 MCI 参与者和健康个体方面具有良好的性能（AUC=0.91）。
较高的饮食质量与 MCI 风险降低相关，这可能是通过微生物群组成和 miRNA 表达介导的。这些发现表明，饮食、肠道微生物群和 miRNAs 可能作为组合生物标志物用于识别 MCI 患者，并为 MCI 的诊断和预防提供新的见解。本研究在中国临床试验注册中心注册，注册号为 ChiCTROOC-17011882。
