Tiamulin inhibits TNF-α and alleviates psoriasis-like dermatitis.

Background: TNF-α elicits a cascade amplification effect in psoriasis. Macromolecule drugs targeting TNF-α are widely used for the clinical treatment of psoriasis. However, there are currently no effective small-molecule inhibitors that can be used in the clinic.

Objective: Novel TNF-α inhibitor was identified via high-throughput screening (HTS) and its anti-inflammatory activity was evaluated.

Methods: Two cell death models were established to identify inhibitors of TNF-α through HTS from a library of 3256 compounds. The effect of the inhibitor of TNF-α was tested by HaCaT cells in vitro and IMQ-induced psoriasis-like mouse model in vivo.

Results: Tiamulin fumarate (TF) was identified as an effective inhibitor of TNF-α. TF significantly blocked the NF-κB and MAPK signaling pathways in TNF-α-stimulated HaCaT cells. Additionally, systemic and topical administration of TF improved IMQ-induced psoriasis-like dermatitis in the mouse model.

Conclusion: Our study established a HTS method to identify TF as an inhibitor of TNF-α. The protective roles of TF in psoriasis-related inflammation reveal the potential therapeutic value of TF for psoriasis.