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bioRxiv · 10.1101/2024.07.10.602891

Sleep induced by mechanosensory stimulation provides cognitive and health benefits in Drosophila

Abstract

Study ObjectivesSleep is a complex phenomenon regulated by various factors, including sensory input. Anecdotal observations have suggested that gentle rocking helps babies fall asleep, and experimental studies have verified that rocking promotes sleep in both humans and mice. Recent studies have expanded this understanding, demonstrating that gentle vibration also induces sleep in Drosophila. Natural sleep serves multiple functions, including learning and memory, synaptic downscaling, and clearance of harmful substances associated with neurodegenerative diseases. Here, we investigated whether vibration-induced sleep provides similar cognitive and health benefits in Drosophila. MethodsWe administered gentle vibration to flies that slept very little due to a forced activation of wake-promoting neurons and investigated how the vibration influenced learning and memory in the courtship conditioning paradigm. Additionally, we examined the effects of VIS on synaptic downscaling by counting synapse numbers of select neurons. Finally, we determined whether vibration could induce sleep in Drosophila models of Alzheimers disease (AD) and promote the clearance of Amyloid {beta} (A{beta}) and Tubulin Associated Unit (TAU). ResultsVibration-induced sleep enhanced performance in a courtship conditioning paradigm and reduced the number of synapses in select neurons. Moreover, vibration improved sleep in Drosophila models of AD, promoting the clearance of A{beta} and TAU. ConclusionsMechanosensory stimulation offers a promising non-invasive avenue for enhancing sleep, potentially providing associated cognitive and health benefits. Significance StatementSleep is critical for a healthy mind and body, and sleep disturbances are commonly associated with neurodegenerative diseases such as Alzheimers disease. Sleep is influenced by sensory input, and mechanical stimulation, such as gentle rocking and vibration, has been shown to promote sleep in various species, including humans, mice, and fruit flies. This study demonstrates that gentle vibration not only helps flies sleep better but also improves their performance in a learning and memory task and makes their brains more efficient in clearing harmful substances. Notably, vibration can facilitate the clearance of Amyloid {beta} and the TAU proteins, which accumulate in Alzheimers disease. These results highlight the potential for gentle mechanosensory stimulation to promote sleep and cognitive health.

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BibTeXRIS

Inami, S., Koh, K.. 2024-07-12. Sleep induced by mechanosensory stimulation provides cognitive and health benefits in Drosophila. https://doi.org/10.1101/2024.07.10.602891

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