Human Mutations in the TRPV1 Channel: Implications for Noxious Cold Sensation

Abstract

Sensing specific temperature ranges as noxious is crucial for protecting organisms from tissue damage. While the molecular detectors for noxious heat are well-characterized, those responsible for noxious cold detection remain elusive. The transient receptor potential vanilloid 1 (TRPV1) is a polymodal channel activated by heat, acid, and various animal and plant toxins. Due to its association with inflammatory pain, TRPV1 has become a promising target for analgesic development. A recent study reported on an individual carrying a homozygous TRPV1 mutation (N331K) that led to pronounced functional loss. Examination of the affected individual revealed an expected decrease in sensitivity to noxious heat and an unexpected increase in sensitivity to noxious cold. Furthermore, extensive neurogenic inflammatory, flare, and pain responses were observed following the application of a TRPA1 channel activator. These findings suggest that the combined activity of TRPV1 and TRPA1 is essential for controlling noxious cold sensitivity and should be considered when assessing TRPV1 pharmacology.