Pharmacological targeting of neuronal Kv7.2/3 channels: A focus on chemotypes and receptor sites

Background: The Kv7 (KCNQ) subfamily of voltage-gated potassium channels consists of 5 members (Kv7.1-5) each showing characteristic tissue distribution and physiological roles. Given their functional heterogeneity, Kv7 channels represent important pharmacological targets for the development of new drugs for neuronal, cardiovascular and metabolic diseases. Objective: In the present manuscript, we focus on describing the pharmacological relevance and potential therapeutic applications of drugs acting on neuronally-expressed Kv7.2/3 channels, placing particular emphasis on the different chemotypes, and highlighting their pharmacodynamic and, whenever possible, pharmacokinetic peculiarities. Methods: The present work is based on an in-depth search of the currently available scientific literature, and on our own experience and knowledge in the field of neuronal Kv7 channel pharmacology. Space limitations impeded to describe the full pharmacological potential of Kv7 channels; thus, we have chosen to focus on neuronal channels composed of Kv7.2 and Kv7.3 subunits, and to mainly concentrate on their involvement in epilepsy. Results: An astonishing heterogeneity in the molecular scaffolds exploitable to develop Kv7.2/3 modulators is evident, with important structural/functional peculiarities of distinct compound classes. Conclusion: In the present work we have attempted to show the current status and growing potential of the Kv7 pharmacology field. We anticipate a bright future for the field, and express our hopes that the efforts herein reviewed will result in an improved treatment of hyperexcitability (or any other) diseases.