Fecal microbiota transplantation from mice exposed to chronic intermittent hypoxia elicits sleep disturbances in naive mice

Obstructive sleep apnea (OSA) is a chronic prevalent condition characterized by intermittent hypoxia (IH) and sleep fragmentation (SF). Evidence suggests that OSA can alter the gut microbiome (GM) diversity and composition that may then promote the occurrence of some of the OSA-associated morbidities. However, it is unclear whether perturbations in the GM caused by IH can elicit sleep disturbances that underlie the increased sleep propensity that occurs in IH-exposed mice. To evaluate this issue, we exposed C57Bl/6 J mice to IH or room air (RA) for 6 weeks, and fecal matter was collected and frozen. C57Bl/6 J naive mice were then randomly assigned to a fecal microbiota transfer (FMT) protocol for 3 weeks with either IH or RA fecal slur, and their GM was then analyzed using 16 s rRNA sequencing. In addition, FMT recipients underwent sleep recordings using piezoelectric approaches for 3 consecutive days. As anticipated, FMT-IH and FMT-RA mice showed different taxonomic profiles that corresponded to previous effects of IH on GM. Furthermore, FMT-IH mice exhibited increased sleep duration and the frequency of longer sleep bouts during the dark cycle, suggesting increased sleepiness (p < 0.0001 vs. FMT-RA mice). Thus, alterations of GM diversity induced by IH exposures can elicit sleep disturbances in the absence of concurrent IH, suggesting that sleep disturbances can be mediated, at least in part, by IH-induced alterations in GM.