Characterization of New TRPM8 Modulators in Pain Perception

Background: Transient Receptor Potential Melastatin-8 (TRPM8) is a non-selective cation channel activated by cold temperature and by cooling agents. Several studies have proved that this channel is involved in pain perception. Although some studies indicate that TRPM8 inhibition is necessary to redu...

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Detalles Bibliográficos
Autores: De Caro, C., Cristiano, C., Avagliano, C., Bertamino, A., Ostacolo, C., Campiglia, P., Gomez-Monterrey, I., La Rana, G., Gualillo ., Oreste, Calignano, A., Russo, R.
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Servizo Galego de Saúde (SERGAS)
Repositorio:RUNA. Repositorio da Consellería de Sanidade e Sergas
OAI Identifier:oai:runa.sergas.gal:20.500.11940/15414
Acceso en línea:https://www.ncbi.nlm.nih.gov/pubmed/31703254
http://hdl.handle.net/20.500.11940/15414
Access Level:acceso abierto
Palabra clave:Pain Perception
Rats
Analgesics
Mice
Pain
TRPM Cation Channels
Animals
dolor
animales
analgésicos
percepción del dolor
canales catiónicos TRPM
ratas
ratones
IDIS
CHUS
Descripción
Sumario:Background: Transient Receptor Potential Melastatin-8 (TRPM8) is a non-selective cation channel activated by cold temperature and by cooling agents. Several studies have proved that this channel is involved in pain perception. Although some studies indicate that TRPM8 inhibition is necessary to reduce acute and chronic pain, it is also reported that TRPM8 activation produces analgesia. These conflicting results could be explained by extracellular Ca2+-dependent desensitization that is induced by an excessive activation. Likely, this effect is due to phosphatidylinositol 4,5-bisphosphate (PIP2) depletion that leads to modification of TRPM8 channel activity, shifting voltage dependence towards more positive potentials. This phenomenon needs further evaluation and confirmation that would allow us to understand better the role of this channel and to develop new therapeutic strategies for controlling pain. Experimental approach: To understand the role of TRPM8 in pain perception, we tested two specific TRPM8-modulating compounds, an antagonist (IGM-18) and an agonist (IGM-5), in either acute or chronic animal pain models using male Sprague-Dawley rats or CD1 mice, after systemic or topical routes of administration. Results: IGM-18 and IGM-5 were fully characterized in vivo. The wet-dog shake test and the body temperature measurements highlighted the antagonist activity of IGM-18 on TRPM8 channels. Moreover, IGM-18 exerted an analgesic effect on formalin-induced orofacial pain and chronic constriction injury-induced neuropathic pain, demonstrating the involvement of TRPM8 channels in these two pain models. Finally, the results were consistent with TRPM8 downregulation by agonist IGM-5, due to its excessive activation. Conclusions: TRPM8 channels are strongly involved in pain modulation, and their selective antagonist is able to reduce both acute and chronic pain.