Abstract
OBJECTIVE: To observe the effects of restricted and high-fat diets on behavioral changes of wild-type (Adrb1(+/+)) and transgenic mice carrying Adrb1-A187V mutation (Adrb1(+/m)) with short sleep durations. METHODS: Adrb1(+/+) and Adrb1(+/m) C57BL/6 mice were randomized into normal chow group (25 Adrb1(+/+) and 26 Adrb1(+/m) mice for behavioral monitoring), odor retention fasting group (17 Adrb1(+/+) and 19 Adrb1(+/m) mice for behavioral monitoring; 6 Adrb1(+/+) mice and 6 Adrb1(+/m) mice for EEG/EMG monitoring), absolute fasting group (6 Adrb1(+/+) and 4-5 Adrb1(+/m) mice for behavioral monitoring; 6 Adrb1(+/+) and 6 Adrb1(+/m) mice for EEG/EMG monitoring), and high-fat diet group (6 Adrb1(+/+) and 7 Adrb1(+/m) mice for behavioral monitoring; 6 Adrb1(+/+) and 6 Adrb1(+/m) mice for EEG/EMG monitoring). Electrodes for EEG and muscle activity monitoring were implanted on the skulls of the mice. After 24 h of odor retention fasting, absolute fasting, or high-fat feeding, the mice were observed for behavioral changes adapted to diet changes. RESULTS: In odor retention fasting experiment, Adrb1(+/m) mice exhibited more stable fluctuations of activities with mildly reduced movement and prolonged sleep duration, indicating enhanced starvation resistance. In absolute fasting experiment, Adrb1(+/m) mice showed significantly increased nighttime water intake, improved rhythmicity in water intake (frequent intakes in small amounts), and increased duration of non-rapid eye movement sleep (NREM). In the high-fat diet experiment, Adrb1(+/m) mice showed higher levels of activity with increased instances of nighttime rearing, longer movement distances, and increased rapid eye movement sleep during daytime. CONCLUSION: Adrb1(+/m) mice can quickly respond to environmental changes and under restricted dietary conditions, they can conserve energy by increasing sleep to maintain energy homeostasis but show higher levels of activity under high-fat dietary conditions.