Modulation of Plet1 expression by N-Acetylglucosamine through the IL-17 A-MAPK pathway in an imiquimod-induced psoriasis mouse model

Psoriasis (Ps) is a chronic inflammatory disorder marked by skin plaque formation, driven by immune dysregulation and genetic factors. Despite the available treatments, incidence of Ps is increasing in the dermatology patients. Novel strategies are crucial due to current treatment limitations. The interleukin 17 (IL-17) pathway is pivotal in Ps pathogenesis, however the expression of its putative target gene placenta expressed transcript 1 (Plet1) remains unstudied in Ps. Considering the potential anti-inflammatory properties of N-Acetylglucosamine (GlcNAc), our study explored its role in modulating Plet1 expression in an imiquimod (IMQ)-induced Ps mouse model. Our data demonstarted a significant reduction of inflammation and Psoriasis Area and Severity Index (PASI) scores, downregulation of growth factors (GFs), IL-17 A, and MAPK expression after GlcNAc treatment. In addition, GlcNAc treatment reduced neutrophils, monocyte-dendritic cells (Mo-DC) and conventional T cells (Tcons) while increasing monocyte-macrophages (Mo-Macs) and regulatory T cells (Tregs). GlcNAc treatment also downregulated Plet1 overexpression in psoriatic mouse skin and in vitro, reduced proliferation and apoptosis in IL-17 A stimulated human dermal fibroblasts (HDF), along with IL-17 A and TGF-beta mRNA expression. Together, these data suggest that, GlcNAc interferes with downstream mechanisms in IL-17 pathway and downregulating Plet1 expression, presenting a promising strategy for Ps treatment.