Rhythmicity of the intestinal microbiota is regulated by gender and the host circadian clock

Abstract

In mammals, multiple physiological, metabolic, and behavioral processes are subject to circadian rhythms, adapting to changing light in the environment. Here we analyzed circadian rhythms in the fecal microbiota of mice using deep sequencing, and found that the absolute amount of fecal bacteria and the abundance of Bacteroidetes exhibited circadian rhythmicity, which was more pronounced in female mice. Disruption of the host circadian clock by deletion of Bmal1, a gene encoding a core molecular clock component, abolished rhythmicity in the fecal microbiota composition in both genders. Bmal1 deletion also induced alterations in bacterial abundances in feces, with differential effects based on sex. Thus, although host behavior, such as time of feeding, is of recognized importance, here we show that sex interacts with the host circadian clock, and they collectively shape the circadian rhythmicity and composition of the fecal microbiota in mice.microbiome | Bmal1 gene | circadian rhythm | gender differences

Human and rat gut microbiome composition is maintained following sleep restriction

“…3B). A sample was included only if it was produced between ZT0 and ZT6 (0800-1400), because the microbiome is known to display circadian oscillations (41,42). In our initial analysis, only the samples from subjects who produced and collected fecal samples during the first three study periods (B, first SR, first R) were processed (n = 15).…”

“…We also included a second bout of sleep restriction in our protocol, which reduces the likelihood of false positive correlations. Finally, our protocol examined the microbiome at a consistent circadian time, because time of day has also been shown to influence gut microbiota (41,42).…”

Circadian Clocks and Metabolism: Implications for Microbiome and Aging

“…Several studies of enteral microbiota composition reveal circadian oscillations in the relative abundance of approximately 15% of various bacterial taxa representing 60% of the total gut bacteria [57–62]. At least one species of enteral microbiota, enterobacter aerogenes, expresses diurnal rhythms when isolated outside of the human gut [63].…”

A place for host–microbe symbiosis in the comparative physiologist's toolbox

“…Exposure of laboratory mice to low ambient temperatures affects their gut microbial communities and thereby alters biological functions -including gene expression and other biochemical processes -in host tissues that are responsive to microbial activity (Chevalier et al, 2015;Zietak et al, 2016). Microbiome structure and function can also be influenced by host sex (Bolnick et al, 2014;Liang et al, 2015), circadian rhythms (Liang et al, 2015;Thaiss et al, 2014), exercise (Allen et al, 2015;Mika et al, 2015), psychological stress (Galley et al, 2014) and social interactions (Moeller et al, 2016;Tung et al, 2015), among other factors.…”