Restoring brain wiring, mobility, sleep, and lifespan with a novel repurposed modulator of voltage-gated K

backgroundVoltage-gated K+ channels (Kv) regulate various essential brain functions. Cognitive impairment, intellectual disability, and sleep disruption are prevalent in Kv1.1- and Kv1.2-related channelopathies, yet the mechanistic basis is unresolved and no symptom-specific repurposing candidates for pharmacotherapy have been identified. Furthermore, the role Kv channels play in establishing synaptic wiring—the intricate network of neuron-to-neuron connections that underpins communication within the brain that is fundamental to cognitive functions—remains poorly understood at ultrastructural level.

methodWe employed a multidisciplinary experimental approach integrating ultrastructural, biochemical, electrophysiological and behavioral analyses to investigate the impact of Shaker K+ channel mutation on synaptic connections in the brain of Drosophila melanogaster flies Sh and to identify drugs with repurposing potential. In the protocerebrum, T-bars density and morphology was assessed using transmission electron microscopy while the concentration of the drug in the brain was measured by UHPLC–MS/MS. Survival and motor behavior were evaluated via lifespan and climbing assays, while sleep was quantified using the Drosophila Activity Monitoring System. The functional effects of the drug on ion channels were studied using two-electrode voltage-clamp in Xenopus laevis oocytes and whole-cell patch-clamp recordings in differentiated Neuro-2a cells. Finally, evoked post-synaptic potentials were recorded to assess neuromuscular transmission efficacy.

resultsMutant Sh flies exhibit impaired neuromuscular transmission, climbing ability, and sleep duration, ultimately shortening lifespan. We observed that all these abnormalities in Sh flies were significantly alleviated by administering low dose of ibuprofen, a widely used non-steroidal anti-inflammatory drug. Through high-resolution ultrastructural analyses, we discovered decreased density of T-bars with morphologically abnormal presynaptic bouton active zones in the brains of Sh flies which were restored by nanomolar concentrations of ibuprofen in their brains. Mechanistically, the drug increased the amplitude of both Shaker currents in Xenopus oocytes and voltage-gated K+ currents in Neuro-2a cells. Collectively, these results identify ibuprofen as a previously unrecognized modulator of Kv channels that restores neuronal network integrity compromised by Shaker K+ channel dysfunction, thereby normalizing neuromuscular signaling and enhancing motor performance, sleep, and longevity in Sh mutant flies. Notably, this study uncovers that genetically-induced dysfunction of Kv1 channels leads to disrupted brain wiring, highlighting the crucial role this K+ channel type plays in establishing proper neuron-to-neuron connections, and offer a pioneering treatment strategy for symptoms-targeted Kv1.1 channelopathies.