Molecular Aspects of Pruritus Pathogenesis in Psoriasis

Abstract

Psoriasis is a chronic, systemic inflammatory disease with a genetic background that involves almost 3% of the general population worldwide. Approximately, 70–90% of patients with psoriasis suffer from pruritus, an unpleasant sensation that provokes a desire to scratch. Despite the enormous progress in understanding the mechanisms that cause psoriasis, the pathogenesis of psoriasis-related pruritus still remains unclear. In order to improve patients’ quality of life, development of more effective and safer antipruritic therapies is necessary. In turn to make it possible, better understanding of complexed and multifactorial pathogenesis of this symptom is needed. In this article we have systematized the current knowledge about pruritus origin in psoriasis.

Characteristics of Pruritus in Various Clinical Variants of Psoriasis: Results of the Multinational, Multicenter, Cross-Sectional Study

“…The pathogenesis of pruritus in psoriasis still remains unclear. Several potential mediators have been proposed, such as substance P, calcitonin gene-related peptide, neuropeptide Y, nerve growth factor and its receptors, lipocalin 2, and interleukin 31; however, data remain controversial and inconclusive [ 5 , 15 , 16 , 38 , 39 , 40 ]. Other authors suggested disturbances in the endogenous opioid system homeostasis, but there is still no final proof that indeed the observed abnormalities are a primary phenomenon in psoriasis leading to pruritus [ 41 , 42 ].…”

“…The knowledge on pruritus in psoriasis is even more limited when considering different clinical subtypes of this disease, as most reports published so far have focused on plaque-type psoriasis. As a consequence, there is a challenge for clinicians to choose the most effective antipruritic treatment for specific subgroups of psoriatic patients [ 5 ]. The aim of this study was to evaluate the relationship between clinical subtypes of psoriasis and the prevalence, intensity, and clinical manifestation of itch.…”

Topical Treatment of Colquhounia Root Relieves Skin Inflammation and Itch in Imiquimod-Induced Psoriasiform Dermatitis in Mice

“…Several researches observed that mast cells are hyperactivated in psoriatic lesions of progressive stage. The use of certain medications to treat psoriasis, such as glucocorticosteroids, may lead a decline of the mast cell count [ 11 ]. Our observation indicates that CR may function as an inhibitor of itch in psoriasis by decreasing the number of mast cells in skin lesions.…”

“…Studies have shown that itch-related molecules released by epidermal keratinocytes and other cells in the dermis such as calcitonin gene-related peptide (CGRP), substance P (SP), nerve growth factor (NGF), and TRPV1 and inflammatory cytokines (IL-17 and IL-22), as well as chemokine CCL20, are important in mechanisms of itch [5][6][7][8][9][10]. Their expressions are significantly increased in the skin specimens of psoriasis patients, involved in the occurrence and development of psoriatic itch [2,11].…”

Alcohol in Psoriasis—From Bench to Bedside

“…In in dividuals carrying 118G, stimulation, sedation and positive mood levels after alcohol in take were significantly higher than in controls [79]. Importantly, OPRM1 is also involved in itch [80], a sensation reported by 70-90% of patients with psoriasis [81], calling for fur ther studies to assess the psoriasis-itch-disease associated stress-alcohol consumption circle both at the level of clinical as well as of genetic studies [82] (Figure 2B).…”