Capsazepine antagonizes TRPV1 activation induced by thermal and osmotic stimuli in human odontoblast-like cells

OBJECTIVES: Dental pain, which is the main reason for patients consulting dentists, is classified as a public health concern. The study of cellular and molecular mechanisms contributing to pain is a fundamental element for developing new analgesics. By using a selective antagonist in an in vitro model, this study aimed to establish the role of TRPV-1 in human odontoblast-like cells (OLCs) as a therapeutic target for dental pain mediated by noxious thermal and osmotic stimuli. METHODS: OLCs were differentiated from dental pulp mesenchymal cells and TRPV1 expression was evaluated. Activation of TRPV-1 was determined by evaluating changes in calcium concentration after stimulation with mannitol and xylitol hyperosmotic solutions or DMEM heated at 45 °C, using the fluorescent calcium probe Fluo-4 AM. In addition, changes in fluorescence (F/F0) due to calcium flux were evaluated using fluorometry and flow cytometry. Simultaneously, the cells were co-stimulated with the selective antagonist capsazepine (CZP). RESULTS: OLCs expressed DSPP and DMP-1, confirming their cellular phenotype. TRPV1 was expressed, and its activation by different stimuli produced an increase in cytosolic Ca(2+) which was reduced by the antagonist. Both methods used to evaluate TRPV1 activation through the measurement of calcium probe fluorescence showed similar patterns. CONCLUSIONS: These results suggest that TRPV-1 modulation using an antagonist can be implemented as a pharmacological strategy for managing dental pain mediated by hyperosmotic and thermal stimuli.