Cinnamaldehyde reduces inflammatory responses in chronic rhinosinusitis by inhibiting TRPM8 expression.

Objective: This study aimed to investigate the effects of cinnamaldehyde (CA) intervention on transient receptor potential melastatin 8 (TRPM8) expression in human nasal epithelial cells (HNECs) and mouse models of chronic rhinosinusitis (CRS) and determine the alleviating effects of CA on CRS.

Methods: HNECs were treated with CA, and the protein levels and mRNA expression of pro-inflammatory cytokines, namely, interleukin-25 (IL-25), IL-33, and thymic stromal lymphopoietin (TSLP), were measured by enzyme-linked immunosorbent assay and real-time reverse-transcription polymerase chain reaction (RT-PCR). TRPM8 expression levels were examined by RT-PCR and western blot.