In lesional skin, SYD treatment was associated with significant suppression of the IL-17 signaling pathway, along with activation of keratinocyte differentiation-related pathways were activated, promoting tissue repair.<h4>Conclusion</h4>Our study suggests that acetate derived from gut microbiota may serve as an important link between SYD treatment and systemic immune regulation in psoriasis, highlighting the potential of the gut-spleen-skin axis as a target for traditional herbal interventions. Here, IL17A is linked to psoriasis.