Cannabidiol Alleviates Imiquimod-Induced Psoriasis by Inhibiting JAK2–STAT3 in a Mouse Model

Cannabidiol (CBD), a non-psychoactive compound from Cannabis sativa, has shown efficacy in treating psoriasis, a chronic inflammatory skin disease affecting 1–3% of the global population; however, the mechanisms remain unclear. This study investigated CBD’s effects on imiquimod (IMQ)-induced psoriasis in mice, which were divided into five groups: Control, IMQ, Clobetasol, 0.01% CBD, and 0.1% CBD. After inducing psoriasis with IMQ, clobetasol or CBD was applied. Psoriasis severity was assessed using the Psoriasis Area and Severity Index (PASI), with histopathological changes examined via hematoxylin and eosin staining. Gene expression of inflammatory markers (Il1b, Il6, Il12b, Il17a, Il22, and Tnf) was analyzed by RT-PCR, while protein levels of signal transducer and activator of transcription (STAT)3, P-STAT3, Janus kinase (JAK)2, and JAK3 were evaluated through western blot and immunohistochemistry. The results demonstrated that CBD significantly reduced PASI scores, epidermal thickness, keratosis, hyperproliferation, and inflammation. Moreover, CBD inhibited the IL-23 receptor-mediated JAK2–STAT3 signaling pathway, leading to the downregulation of Il1b, Il6, Il12b, Il17a, Il22, and Tnf expression. These findings suggest that CBD effectively alleviates psoriasis-like symptoms in mice and may serve as a promising therapeutic agent for psoriasis by targeting the JAK2–STAT3 pathway.