The Therapeutic Effects of Sulfasalazine Ointment on Imiquimod-Induced Psoriasis in Mice

Psoriasis, a chronic inflammatory skin disease affecting 0.6-4.8% of the global population, is characterized by an overproduction of pro-inflammatory cytokines and keratinocyte hyperproliferation. Current treatments often have adverse effects and high costs, necessitating new therapeutic approaches. This study investigated the potential of topical sulfasalazine, a known anti-inflammatory agent, in treating psoriasis-like inflammation using an imiquimod-induced mouse model. A 10% sulfasalazine ointment was formulated and tested against clobetasol propionate ointment and untreated controls. The efficacy was evaluated using the Psoriasis Area and Severity Index (PASI) score, histopathological examination, and measurement of pro-inflammatory cytokines (TNF-α and IL-6). Results showed that sulfasalazine ointment significantly reduced the PASI score by 83.3%, outperforming clobetasol propionate (58.3% reduction). Histopathological analysis revealed improved skin architecture with sulfasalazine treatment, including restoration of normal dermal fibrous tissue and hair follicles. Furthermore, sulfasalazine significantly reduced levels of TNF-α (32.3% reduction) and IL-6 (19.8% reduction) compared to untreated controls. These findings suggest that topical sulfasalazine ointment effectively attenuates inflammation and improves clinical, histological, and molecular features of psoriasis-like lesions, potentially offering a promising alternative or complementary treatment for psoriasis management.