Peking University - Juntendo University Joint Symposium on Brain and Skin Diseases

Abstract

Increased epidermal nerve density is involved in intractable itch in atopic dermatitis. Epidermal innervation is regulated by the balance between nerve growth factors (e.g. NGF) and nerve repulsion factors (e.g. semaphorin 3A, Sema3A) in keratinocytes. Emollient ointment, UV-based therapy, Sema3A ointment and cyclosporine administration decreased the density of epidermal nerve fibers, resulting in improvement of itch. Retinoid-related orphan receptor α (RORα) agonist and LL-37 which induce Sema3A in keratinocytes may be a useful treatment of atopic dermatitis.