0094 Effects of Rocking-induced Sleep Enhancement on Wild Type (WT) and APPxPS1 Knock-in (KI) Alzheimer’s Disease (AD) Mice

Abstract Introduction Passive rhythmic movement–rocking – is found to enhance sleep, particularly in infants and young wild type (WT) mice. Rocking can potentially enhance sleep at all ages, with the added benefit of being non-invasive, easy to translate for human use, and with negligible side effects. Furthermore, sleep enhancement tools should be especially valuable to patients with sleep disturbances, a pervasive feature of age-related dementia including Alzheimer’s disease (AD). However, rocking has not been explored widely as a means of sleep enhancement. Therefore, our study explores the impact of rocking on sleep architecture in both WT and APP/PS1 KI mice (a model of human AD). Methods Male C57BL/6J (WT; n=3) and APPxPS1 KI (AD; n=4) mice (10-12 months old) were kept under a 12h:12h light/dark cycle with access to food and water ad libitum. A reciprocating platform was used to laterally rock individually housed mice at 1 Hz, a rate previously shown to enhance sleep in younger mice, for nine hours during the light period. The experimental protocol consisted of a baseline day, rocking day, and a post-rocking day, with the mice being rocked only during the rocking day for nine hours.EEG/EMG signals were recorded on baseline, rocking, and post-rocking days. Vigilance states (wake, NREM, REM) were scored in 4-second epochs from the EEG/EMG data using standard criteria. Mean bout duration (MBD) and time spent in each vigilance state were estimated and compared for both AD and WT mice. Results In repeated tests (>6 trials per mouse), we observed a significant increase in the NREM (p< 0.001) and decrease in REM (p< 0.05) sleep percent on the rocking versus the non-rocking days in AD but not in WT mice. Additionally, NREM MBD (p< 0.05) significantly increased, and REM MBD (p< 0.05) decreased on rocking versus non-rocking days, only in AD mice. Conclusion Our results suggest that rocking can be a potential tool for sleep enhancement in AD mouse models; investigations on a larger sample are in progress. Future studies will focus on the impact of rocking on cognitive impairment and AD neuropathology, which are linked to sleep disruption. Support (if any) National Institute on Aging (NIA) Grant No:5R01AG068215-02