Quercitrin extracted from Tartary buckwheat alleviates imiquimod-induced psoriasis-like dermatitis in mice by inhibiting the Th17 cell response

- Quercitrin (YDHH) can attenuate IMQ-induced psoriasis-like skin lesions in mice.
- Transcripts of cytokines on the IL-23/Th17 axis were decreased after YDHH treatment.
- YDHH inhibits Th17 cell response via the JAK/STAT signalling pathway.
- Compared with CsA, quercitrin causes less toxicity to the liver and kidneys.

Quercitrin (YDHH) is a natural dietary flavonoid extracted from Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.). Psoriasis is a chronic immune-mediated dermatosis. In this study, we report that YDHH had no obvious cytotoxicity and inhibited the proliferation of LPS-stimulated HaCaT keratinocytes. Furthermore, oral administration of YDHH alleviated imiquimod-induced psoriasis-like dermatitis in mice, significantly attenuating the excessive proliferation and abnormal differentiation of keratinocytes, and reducing inflammatory cell infiltrates. YDHH treatment lowered the expression of cytokines related to psoriasis, especially those on the IL-23/Th17 axis. Furthermore, it dramatically inhibited the Th17 cell response regulated by the JAK/STAT signalling pathway. In addition, it was less toxic to the liver and kidneys of mice than the classical immunosuppressant cyclosporine A. Taken together, these findings indicate that YDHH could be useful as a functional food supplement for protection against psoriasis.