Chronic social stress leads to altered sleep homeostasis in mice.
Disturbed sleep and altered sleep homeostasis are core features of many psychiatric disorders such as depression. Chronic uncontrollable stress is considered an important factor in the development of depression, but little is known on how chronic stress affects sleep regulation and sleep homeostasis. We therefore examined the effects of chronic social stress (CSS) on sleep regulation in mice. Adult male C57BL/6 mice were implanted for electrocortical recordings (ECoG) and underwent either a 10-day CSS protocol or control handling (CON). Subsequently, ECoG was assessed across a 24-h post-stress baseline, followed by a 4-h sleep deprivation, and then a 20-h recovery period. After sleep deprivation, CSS mice showed a blunted increase in sleep pressure compared to CON mice, as measured using slow wave activity (SWA, electroencephalographic power between 1-4Hz) during non-rapid eye movement (NREM) sleep. Vigilance states did not differ between CSS and CON mice during post-stress baseline, sleep deprivation or recovery, with the exception of CSS mice exhibiting increased REM sleep during recovery sleep. Behavior during sleep deprivation was not affected by CSS. Our data provide evidence that CSS alters the homeostatic regulation of sleep SWA in mice. In contrast to acute social stress, which results in a faster SWA build-up, CSS decelerates the homeostatic build up. These findings are discussed in relation to the causal contribution of stress-induced sleep disturbance to depression.
Child Development Center, University Children's Hospital Zurich, CH-8032 Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland.
Nadja
N
Olini
Child Development Center, University Children's Hospital Zurich, CH-8032 Zurich, Switzerland.
Iru
I
Rothfuchs
Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland; Preclinical Laboratory for Translational Research into Affective Disorders, Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, CH-8008 Zurich, Switzerland.
Damiano
D
Azzinnari
Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, CH-8057 Zurich, Switzerland; Preclinical Laboratory for Translational Research into Affective Disorders, Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, CH-8008 Zurich, Switzerland.
Christopher R
CR
Pryce
Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland; Baby Sleep Laboratory, Division of Pulmonology, University Hospital Zurich, CH-8091 Zurich, Switzerland.
Salome
S
Kurth
Child Development Center, University Children's Hospital Zurich, CH-8032 Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, CH-8057 Zurich, Switzerland. Electronic address: Reto.Huber@kispi.uzh.ch.
Reto
R
Huber
D000818:Animals; D001921:Brain / Q000503:physiopathology*; D002908:Chronic Disease; D000069280:Electrocorticography; D006706:Homeostasis / Q000502:physiology*; D008297:Male; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology; D012938:Social Perception; D013315:Stress, Psychological / Q000503:physiopathology*
Chronic stress; Depression; REM sleep; Sleep regulation; Slow wave activity