Inflammation, lipid dysregulation, and transient receptor potential cation channel subfamily V member 4 signaling perpetuate chronic vulvar pain.

Abstract

Localized provoked vulvodynia is characterized by chronic vulvar pain that disrupts every aspect of the patient's life. Pain is localized to the vulvar vestibule, a specialized ring of tissue immediately surrounding the vaginal opening involved in immune defense. In this article, we show inflammation is the critical first step necessary for the generation of pain signals in the vulva. Inflammatory stimuli alone or combined with the transient receptor potential cation channel subfamily V member 4 (TRPV4) agonist 4α-phorbol 12,13-didecanoate stimulate calcium flux into vulvar fibroblast cells. Activity is blocked by the TRPV4 antagonist HC067047, denoting specificity to TRPV4. Using lipidomics, we found pro-resolving lipids in the vulvar vestibule were dysregulated, characterized by a reduction in pro-resolving mediators and heightened production of inflammatory mediators. We demonstrate specialized pro-resolving mediators represent a potential new therapy for vulvar pain, acting on 2 key parts of the disease mechanism by limiting inflammation and acutely inhibiting TRPV4 signaling.