Nrf2 reduces psoriasis skin damage by inhibiting NLRP3

Traditional Chinese medicine (TCM) is effective in treating psoriasis. However, in rare cases, TCM treatment exacerbates skin lesions. In this study, we aim to address the possibility that the MTX ingredient in TCM might increase the risk of cutaneous ulceration in psoriasis patients. We retrospectively analyzed 5 patients who developed painful skin ulcers at primary psoriasis lesions after oral TCM treatment. Blood cell counts, liver function, serum MTX concentration, and ABCB1 gene polymorphisms were assessed, and ulcer biopsies were performed. Two presented hemocytopenia and two abnormal liver function. Two cases showed serum MTX concentration of 0.03-0.11 μmol/L (<0.1mol/L 72h after MTX intaking). The ABCB1genotypes AA and AG were detected in two different patients. Lesions healed completely within two weeks after oral folic acid in 3 patients; ulcers improved in the remaining 2 patients after discontinuing TCM. MTX-containing TCM can incur skin ulceration in rare cases of psoriasis patients.