School of Population Medicine and Public Health, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.
Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou 510515, China.
Nutrients. 2023 Dec 22;16(1):46. doi: 10.3390/nu16010046.
Numerous observational studies have documented an association between the circadian rhythm and the composition of the gut microbiota. However, the bidirectional causal effect of the morning chronotype on the gut microbiota is unknown.
A two-sample Mendelian randomization study was performed, using the summary statistics of the morning chronotype from the European Consortium and those of the gut microbiota from the largest available genome-wide association study meta-analysis, conducted by the MiBioGen consortium. The inverse variance-weighted (IVW), weighted mode, weighted median, MR-Egger regression, and simple mode methods were used to examine the causal association between the morning chronotype and the gut microbiota. A reverse Mendelian randomization analysis was conducted on the gut microbiota, which was identified as causally linked to the morning chronotype in the initial Mendelian randomization analysis. Cochran's Q statistics were employed to assess the heterogeneity of the instrumental variables.
Inverse variance-weighted estimates suggested that the morning chronotype had a protective effect on Family ( = -0.072; 95% CI: -0.143, -0.001; = 0.047), Genus ( = -0.112; 95% CI: -0.184, -0.039; = 0.002), and Genus ( = -0.072; 95% CI: -0.143, -0.001; = 0.047). In addition, the gut microbiota (Family (OR = 0.925; 95% CI: 0.857, 0.999; = 0.047), Genus (OR = 0.915; 95% CI: 0.858, 0.975; = 0.007), and Genus (OR = 0.925; 95% CI: 0.857, 0.999; = 0.047)) demonstrated positive effects on the morning chronotype. No significant heterogeneity in the instrumental variables, or in horizontal pleiotropy, was found.
This two-sample Mendelian randomization study found that Family , Genus , and Genus were causally associated with the morning chronotype. Further randomized controlled trials are needed to clarify the effects of the gut microbiota on the morning chronotype, as well as their specific protective mechanisms.
大量观察性研究记录了昼夜节律与肠道微生物群组成之间的关联。然而，晨型的早晨时间偏好对肠道微生物群的双向因果效应尚不清楚。
使用欧洲联盟的晨型汇总统计数据和 MiBioGen 联盟进行的最大全基因组关联研究荟萃分析的肠道微生物群汇总统计数据，进行了两样本孟德尔随机化研究。使用逆方差加权（IVW）、加权模式、加权中位数、MR-Egger 回归和简单模式方法来检查晨型与肠道微生物群之间的因果关联。对在初始孟德尔随机化分析中被确定为与晨型有因果关系的肠道微生物群进行了反向孟德尔随机化分析。使用 Cochran's Q 统计量评估工具变量的异质性。
逆方差加权估计表明，晨型对科（= -0.072；95% CI：-0.143，-0.001；= 0.047）、属（= -0.112；95% CI：-0.184，-0.039；= 0.002）和属（= -0.072；95% CI：-0.143，-0.001；= 0.047）具有保护作用。此外，肠道微生物群（科（OR = 0.925；95% CI：0.857，0.999；= 0.047）、属（OR = 0.915；95% CI：0.858，0.975；= 0.007）和属（OR = 0.925；95% CI：0.857，0.999；= 0.047））对晨型具有积极影响。未发现工具变量或水平多效性存在显著异质性。
这项两样本孟德尔随机化研究发现，科、属和属与晨型有因果关系。需要进一步的随机对照试验来阐明肠道微生物群对晨型的影响及其特定的保护机制。
