In Vitro and In Vivo Pharmacological Characterization of a Novel TRPM8 Inhibitor Chemotype Identified by Small-Scale Preclinical Screening

Abstract

Transient receptor potential melastatin type 8 (TRPM8) is a target for the treatment of different physio-pathological processes. While TRPM8 antagonists are reported as potential drugs for pain, cancer, and inflammation, to date only a limited number of chemotypes have been investigated and thus a limited number of compounds have reached clinical trials. Hence there is high value in searching for new TRPM8 antagonistic to broaden clues to structure-activity relationships, improve pharmacological properties and explore underlying molecular mechanisms. To address this, the EDASA Scientific in-house molecular library has been screened in silico, leading to identifying twenty-one potentially antagonist compounds of TRPM8. Calcium fluorometric assays were used to validate the in-silico hypothesis and assess compound selectivity. Four compounds were identified as selective TRPM8 antagonists, of which two were dual-acting TRPM8/TRPV1 modulators. The most potent TRPM8 antagonists (BB 0322703 and BB 0322720) underwent molecular modelling studies to highlight key structural features responsible for drug–protein interaction. The two compounds were also investigated by patch-clamp assays, confirming low micromolar potencies. The most potent compound (BB 0322703, IC50 1.25 ± 0.26 μM) was then profiled in vivo in a cold allodinya model, showing pharmacological efficacy at 30 μM dose. The new chemotypes identified showed remarkable pharmacological properties paving the way to further investigations for drug discovery and pharmacological purposes.

Subcutaneous administration of a novel TRPM8 antagonist reverses cold hypersensitivity while attenuating the drop in core body temperature

“…Our behavioural results are partially consistent with our initial hypothesis, with respect to the ability to block environmental coldactivation of TRPM8 in vivo. The antinociceptive effects of VBJ103 are in line with prior studies demonstrating antinociceptive effects of TRPM8-selective antagonists in this model (Bertamino et al, 2018(Bertamino et al, , 2020Bonache et al, 2020;Chaudhari et al, 2013;Iraci et al, 2022;Martin-Escura et al, 2023Mizoguchi et al, 2016). There was no apparent sex difference in efficacy or detectable issues observed with repeat dosing.…”

Roles of TRPM channels in glioma

“…TRPM8 is expressed in a variety of cells, but mainly in the dorsal root and trigeminal ganglion of the peripheral nervous system. 126 In the cell, this channel shows the location of the plasma membrane and membrane raft. However, TRPM8 has also been found in the mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) in prostate cancer cells.…”