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bioRxiv · 10.1101/657387

Selective Activation of TASK-3-containing K+ Channels Reveals Their Therapeutic Potentials in Analgesia

Abstract

The paucity of selective agonists for TASK-3, a member of two-pore domain K+ (K2P) channels, has contributed to our limited understanding of its biological functions. By targeting a novel druggable transmembrane cavity using a structure-based drug design approach, we discovered a biguanide compound, CHET3, as a highly selective allosteric activator for TASK-3-containing K2P channels, including TASK-3 homomer and TASK-3/TASK-1 heteromer. CHET3 displayed unexpectedly potent analgesic effects in vivo in a variety of acute and chronic pain models in rodents that could be abolished by pharmacology or genetic ablation of TASK-3. We further found that TASK-3-containing channels anatomically define a unique subset population of small-sized, TRPM8, TRPV1 or tyrosine hydroxylase-positive nociceptive sensory neurons and functionally regulate their membrane excitability, supporting CHET3 analgesia in thermal hyperalgesia and mechanical allodynia under chronic pain. Overall, our proof-of-concept study reveals TASK-3-containing K2P channels as a novel druggable target for treating pain.\n\nOne Sentence SummaryIdentification of a novel drug target and its new hit compounds for developing new-generation non-opioid analgesics.

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BibTeXRIS

Liao, P., Qiu, Y., Mo, Y., Fu, J., Song, Z., Huang, L., Bai, S., Wang, Y., Zhu, J. J., Tian, F., Chen, Z., Pan, N., Sun, E. Y., Yang, L., Lan, X., Chen, Y., Huang, D., Sun, P., Zhao, L., Yang, D., Lu, W., Yang, T., Xiao, J., Li, W. G., Gao, Z., Shen, B., Zhang, Q., Liu, J., Jiang, H., Jiang, R., Yang, H.. 2019-06-05. Selective Activation of TASK-3-containing K+ Channels Reveals Their Therapeutic Potentials in Analgesia. https://doi.org/10.1101/657387

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