Oral and gut microbiome in chronic sleep restriction mice models

Abstract

Reduced sleep quality is a common problem in the US, linked to increased risk for several disease conditions. Current evidence indicates an association between the gut microbiome and sleep modulation. With the ease of access to the oral cavity for examination and sampling, correlations between the gut and oral microbiome have clinical implications for developing health screening tools. Based on this relationship, this study examined whether changes in the gut microbiome of chronically sleep-restricted subjects were reflected in their oral microbiome. Mice models were placed on chronic sleep restriction for six weeks via the Modified Multiple Platform Method. Additionally, LPS injections were given to mice four hours prior to euthanasia (saline given to control group). Oral swabs and fecal samples were collected to profile the microbiomes, characterized using Miseq for sequencing the V4 region of the 16S rRNA gene. The oral samples exhibited less diverse range of phyla, favoring Proteobacteria and Firmicutes; while the gut samples exhibited more diverse range. Among the oral microbiome profile, only Firmicutes indicated a possible association to sleep restriction with marked decrease in abundance compared to the control mice's oral samples. Among the fecal microbiome phylum analysis, two samples (S13, S21) consistently clustered away from the rest were under the conditions of no sleep restriction with LPS injection. Unexpectedly, not all of the mice which received LPS injections clustered together on PCoA. Additional studies with larger sample size are necessary to further understand the complex mechanisms taking place.