• Takashi Hashimoto, Kent Sakai, Kristen M Sanders, Gil Yosipovitch, and Tasuku Akiyama.
• Department of Dermatology and Cutaneous Surgery, Miami Itch Center, University of Miami, 1600 NW 10th Ave RMSB2063, Miami, FL 33136, USA.
• Acta Derm. Venereol. 2019 Mar 1; 99 (3): 298-303.

AbstractThe Janus kinase 1/3 inhibitor tofacitinib has demonstrated an antipruritic effect in two phase III studies in psoriasis. However, the mechanisms behind this antipruritic effect are still unknown. We presently investigated whether tofacitinib affects spontaneous itch as well as expression of itch-related cytokines and epidermal nerve fiber density (ENFD) in the imiquimod-induced mouse model of psoriasis. Psoriasis-like skin lesions were produced by daily topical application of imiquimod to the back skin. Imiquimod treatment resulted in spontaneous scratching, which was significantly inhibited by tofacitinib treatment. Imiquimod treatment significantly increased mRNA expression of Il22, Il23, and Il31, reduced peptidergic ENFD, and increased nonpeptidergic ENFD compared to naive mice. Tofacitinib significantly decreased the expression of those cytokines and increased peptidergic ENFD without a significant effect on nonpeptidergic ENFD. Tofacitinib may inhibit psoriatic itch through inhibition of cytokine expression as well as modulation of epidermal innervation.

46 keywords...

hide…