Bidirectional regulation of glial potassium buffering: glioprotection versus neuroprotection
- Washington University School of Medicine, United States
Abstract
Glia modulate neuronal excitability and seizure sensitivity by maintaining potassium and water homeostasis. A SIK3-regulated gene expression program controls the glial capacity to buffer K+ and water in Drosophila, however upstream regulatory mechanisms are unknown. Here we identify an octopaminergic circuit linking neuronal activity to glial ion and water buffering. Under basal conditions, octopamine functions through the inhibitory octopaminergic GPCR OctbR to upregulate glial buffering capacity, while under pathological K+ stress, octopamine signals through the stimulatory octopaminergic GPCR OAMB1 to downregulate the glial buffering program. Failure to downregulate this program leads to intracellular glia swelling and stress signaling, suggesting that turning down this pathway is glioprotective. In the eag shaker Drosophila seizure model, the SIK3-mediated buffering pathway in inactivated. Re-activation of the glial buffering program dramatically suppresses neuronal hyperactivity, seizures, and shortened lifespan in this mutant. These findings highlight the therapeutic potential of a glial-centric therapeutic strategy for diseases of hyperexcitability.
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All data generated or analyzed during this study are included in the manuscript.
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Author details
Funding
National Institutes of Health (NS065053)
- Aaron DiAntonio
American Heart Association (18PRE34030101)
- Hailun Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Li et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Bidirectional regulation of glial potassium buffering: glioprotection versus neuroprotection
eLife 10:e62606.
https://doi.org/10.7554/eLife.62606
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