Sustained sleep fragmentation induces sleep homeostasis in mice
Type
Article
KAUST Department
Biological and Environmental Sciences and Engineering (BESE) DivisionBioscience Program
Date
2015-04-01Online Publication Date
2015-04-01Print Publication Date
2015-04Permanent link to this record
http://hdl.handle.net/10754/564135Metadata
Show full item recordAbstract
Study Objectives: Sleep fragmentation (SF) is an integral feature of sleep apnea and other prevalent sleep disorders. Although the effect of repetitive arousals on cognitive performance is well documented, the effects of long-term SF on electroencephalography (EEG) and molecular markers of sleep homeostasis remain poorly investigated. To address this question, we developed a mouse model of chronic SF and characterized its effect on EEG spectral frequencies and the expression of genes previously linked to sleep homeostasis including clock genes, heat shock proteins, and plasticity-related genes. Design: N/A. Setting: Animal sleep research laboratory. Participants : Sixty-six C57BL6/J adult mice. Interventions: Instrumental sleep disruption at a rate of 60/h during 14 days Measurements and Results: Locomotor activity and EEG were recorded during 14 days of SF followed by recovery for 2 days. Despite a dramatic number of arousals and decreased sleep bout duration, SF minimally reduced total quantity of sleep and did not significantly alter its circadian distribution. Spectral analysis during SF revealed a homeostatic drive for slow wave activity (SWA; 1-4 Hz) and other frequencies as well (4-40 Hz). Recordings during recovery revealed slow wave sleep consolidation and a transient rebound in SWA, and paradoxical sleep duration. The expression of selected genes was not induced following chronic SF. Conclusions: Chronic sleep fragmentation (SF) increased sleep pressure confirming that altered quality with preserved quantity triggers core sleep homeostasis mechanisms. However, it did not induce the expression of genes induced by sleep loss, suggesting that these molecular pathways are not sustainably activated in chronic diseases involving SF.Citation
Baud, M. O., Magistretti, P. J., & Petit, J.-M. (2015). Sustained Sleep Fragmentation Induces Sleep Homeostasis in Mice. Sleep, 38(4), 567–579. doi:10.5665/sleep.4572Sponsors
This work was supported by a Swiss National Science Foundation grant (3100AO-108336/1) to Dr. Magistretti. Dr. Baud's work was directly supported by a Swiss National Science Foundation personal MD-PhD grant (323600-119351/1). The authors have indicated no financial conflicts of interest.Publisher
Oxford University Press (OUP)Journal
SLEEPPubMed ID
25325477PubMed Central ID
PMC4355896Additional Links
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4355896Scopus Count
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