Sleep Behavior and EEG Oscillations in Aged Dp(16)1Yey/+ Mice: A Down Syndrome Model

Area of Science:

• Neuroscience
• Genetics
• Sleep Medicine

Background:

• Down syndrome (DS) is caused by trisomy of human chromosome 21 (Hsa21).
• Sleep disturbances affect ~60% of individuals with DS but are poorly understood.
• Mouse models offer insights into DS phenotypes.

Purpose of the Study:

• To investigate sleep and EEG oscillations in a mouse model of DS.
• To compare aged Dp(16)1Yey/+ mice (Dp16) with wild-type controls.
• To explore potential mechanisms behind DS-related sleep abnormalities.

Main Methods:

• Recorded sleep and electroencephalography (EEG) in aged Dp16 mice and wild-type littermates.
• Analyzed sleep architecture, including wakefulness and NREM sleep duration.
• Quantified relative EEG power across different oscillation frequencies during sleep and wake states.

Main Results:

• Dp16 mice exhibited disrupted sleep, with increased dark phase activity and more time awake.
• Significant differences in EEG power distribution were observed in Dp16 mice during both sleep and awake states.
• Abnormal EEG oscillations suggest a potential role for GABAergic activity in DS-related sleep disturbances.

Conclusions:

• Sleep and EEG abnormalities in Dp16 mice mirror those seen in humans with DS.
• Altered neuronal network activity, potentially involving GABAergic systems, underlies DS sleep phenotypes.
• These findings suggest sleep disturbances are causative agents, not just symptoms, of DS.