Role of neuromediators in the development of skin inflammation in patients with atopic dermatitis

Abstract

Neurotransmitters such as neuropeptides and neurotrophins can have an effect on the development of a skin inflammatory reaction and itching as well as condition of nerve fibers. Goal. To assess the expression of neuropeptides and neurotrophins in the skin of patients with atopic dermatitis. Materials and methods. Expression of neuropeptides of substance P and SP-R receptor, calcitonin gene-related peptide (CGRP) and CGRP-R receptor, neurotrophin (nerve growth factor) and TrkA receptor as well as amphiregulin enhancing the growth of nerve fibers and semaphorin-3A terminating the growth of nerve fibers was determined in the skin of patients with atopic dermatitis based on the immunohistochemistry analysis method. Expression of protein PGP9.5 being a marker of nerve fibers was also determined. Results. The authors discovered penetration of nerve fibers expressing substance P and CGRP into the epidermis in patients with atopic dermatitis. Expression of the nerve growth factor and amphiregulin was discovered in epidermis but no expression of semaphorin-3A was discovered. Conclusion. Nerve fibers expressing neuropeptides such as substance P and CGRP can penetrate into the epidermis in patients with atopic dermatitis, which can maintain the inflammatory reaction and itching in such patients. Expression of the growth factors (nerve growth factor and amphiregulin) can contribute to the growth of nerve fibers and their penetration into epidermis against the background of the absence of any expression of semaphorin-3A inhibiting their growth.