Ca2+ signaling in astrocytes is sleep-wake state specific and modulates sleep

Bojarskaite, L.; Bjornstad, D. M.; Pettersen, K. H.; Cunen, C.; Hermansen, G. H.; Abjorsbraten, K. S.; Sprengel, R.; Vervaeke, K.; Tang, W.; Enger, R.; Nagelhus, E. A.

doi:10.1101/750281

bioRxiv · 10.1101/750281

Ca2+ signaling in astrocytes is sleep-wake state specific and modulates sleep

Bojarskaite, L.·Bjornstad, D. M.·Pettersen, K. H.·Cunen, C.·Hermansen, G. H.·Abjorsbraten, K. S.·Sprengel, R.·Vervaeke, K.·Tang, W.·Enger, R.·Nagelhus, E. A.

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Abstract

Astrocytic Ca2+ signaling has been intensively studied in health and disease but remains uncharacterized in sleep. Here, we employed a novel activity-based algorithm to assess astrocytic Ca2+ signals in the barrel cortex of awake and naturally sleeping mice while monitoring neuronal Ca2+ activity, brain rhythms and behavior. We discovered that Ca2+ signaling in astrocytes exhibits distinct features across the sleep-wake cycle and is reduced in sleep compared to wakefulness. Moreover, an increase in astrocytic Ca2+ signaling precedes transitions from slow-wave sleep to wakefulness, with a peak upon awakening exceeding the levels during whisking and locomotion. Genetic ablation of a key astrocytic Ca2+ signaling pathway resulted in fragmentation of slow-wave sleep, yet increased the frequency of sleep spindles. Our findings suggest a role for astrocytic Ca2+ signaling in modulating sleep.

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Bojarskaite, L., Bjornstad, D. M., Pettersen, K. H., Cunen, C., Hermansen, G. H., Abjorsbraten, K. S., Sprengel, R., Vervaeke, K., Tang, W., Enger, R., Nagelhus, E. A.. 2019-08-29. Ca2+ signaling in astrocytes is sleep-wake state specific and modulates sleep. https://doi.org/10.1101/750281

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