Kim Hyun-Jung, Moon Chang Mo, Kang Jihee Lee, Park Eun-Mi
Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul 07084, Korea.
Department of Internal Medicine, College of Medicine, Ewha Womans University, Seoul 07084, Korea.
Korean J Physiol Pharmacol. 2021 Nov 1;25(6):575-583. doi: 10.4196/kjpp.2021.25.6.575.
Composition of the gut microbiota changes with aging and plays an important role in age-associated disease such as metabolic syndrome, cancer, and neurodegeneration. The gut microbiota composition oscillates through the day, and the disruption of their diurnal rhythm results in gut dysbiosis leading to metabolic and immune dysfunctions. It is well documented that circadian rhythm changes with age in several biological functions such as sleep, body temperature, and hormone secretion. However, it is not defined whether the diurnal pattern of gut microbial composition is affected by aging. To evaluate aging effects on the diurnal pattern of the gut microbiome, we evaluated the taxa profiles of cecal contents obtained from young and aged mice of both sexes at daytime and nighttime points by 16S rRNA gene sequencing. At the phylum level, the ratio of Firmicutes to Bacteroidetes and the relative abundances of Verrucomicrobia and Cyanobacteria were increased in aged male mice at night compared with that of young male mice. Meanwhile, the relative abundances of Sutterellaceae, , Lachnospiraceae UCG-001, and increased in aged female mice at night compared with that of young female mice. The Lachnospiraceae NK4A136 group relative abundance increased in aged mice of both sexes but at opposite time points. These results showed the changes in diurnal patterns of gut microbial composition with aging, which varied depending on the sex of the host. We suggest that disturbed diurnal patterns of the gut microbiome can be a factor for the underlying mechanism of age-associated gut dysbiosis.
肠道微生物群的组成随衰老而变化，并在与年龄相关的疾病如代谢综合征、癌症和神经退行性变中发挥重要作用。肠道微生物群的组成在一天中会发生波动，其昼夜节律的破坏会导致肠道生态失调，进而引发代谢和免疫功能障碍。有充分的文献记载，昼夜节律在睡眠、体温和激素分泌等多种生物学功能中会随年龄而变化。然而，肠道微生物组成的昼夜模式是否受衰老影响尚未明确。为了评估衰老对肠道微生物群昼夜模式的影响，我们通过16S rRNA基因测序评估了白天和夜间从年轻和老年雌雄小鼠盲肠内容物中获得的分类群概况。在门水平上，与年轻雄性小鼠相比，老年雄性小鼠夜间厚壁菌门与拟杆菌门的比例以及疣微菌门和蓝细菌的相对丰度增加。同时，与年轻雌性小鼠相比，老年雌性小鼠夜间萨特氏菌科、毛螺菌科UCG - 001等的相对丰度增加。毛螺菌科NK4A136组的相对丰度在老年雌雄小鼠中均增加，但时间点相反。这些结果表明，肠道微生物组成的昼夜模式随衰老而变化，且因宿主性别而异。我们认为，肠道微生物群昼夜模式紊乱可能是与年龄相关的肠道生态失调潜在机制的一个因素。
