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bioRxiv · 10.1101/2023.09.18.558258

Attenuating midline thalamus bursting to mitigate absence epilepsy

Abstract

Advancing the mechanistic understanding of absence epilepsy is crucial for developing new therapeutics, especially for patients unresponsive to current treatments. Utilizing a recently developed mouse model of absence epilepsy carrying the BK gain-of-function channelopathy D434G, here we report that attenuating the burst firing of midline thalamus (MLT) neurons effectively prevents absence seizures. We found that enhanced BK channel activity in the BK-D434G MLT neurons promotes synchronized bursting during the ictal phase of absence seizures. Modulating MLT neurons through pharmacological reagents, optogenetic stimulation, or deep brain stimulation effectively attenuates burst firing, leading to reduced absence seizure frequency and increased vigilance. Additionally, enhancing vigilance by amphetamine, a stimulant medication, or physical perturbation also effectively suppresses MLT bursting and prevents absence seizures. These findings suggest that the MLT is a promising target for clinical interventions. Our diverse approaches offer valuable insights for developing new therapeutics to treat absence epilepsy. HighlightsThe midline thalamus (MLT) is a key thalamic region for absence seizure pathogenesis MLT neurons exhibit synchronized bursting during ictal phase. BK channel contributes to MLT burst firing Attenuating MLT bursting increases vigilance and suppresses absence seizures

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Dong, P., Bakhurin, K., Li, Y., Mikati, M. A., Cui, J., Grill, W. M., Yin, H., Yang, H.. 2023-09-18. Attenuating midline thalamus bursting to mitigate absence epilepsy. https://doi.org/10.1101/2023.09.18.558258

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