High-salt diet aggravates skin inflammation of psoriasis-like mouse model with CCL20‒CCR6 axis further activation.

Epidermal keratinocytes are important for maintaining the skin barrier by interacting with immune cells and environmental stimuli. In this study, we reveal that a high-salt diet aggravated imiquimod-induced skin inflammation in a psoriasis-like mouse model, characterized by activation of the CCL20-CCR6 axis and increased infiltration of CCR6(+) γδT cells in skin lesions. In the presence of additional sodium, the mRNA expression of Ccl20 was upregulated in keratinocytes, mediated by JNK/p38-SGK1 pathway. Consistent with our experimental findings, a positive correlation between SGK1 and CCL20 gene expression was also observed in the skin of patients with psoriasis. Taken together, these data demonstrated that a high-salt diet aggravated skin inflammation in a psoriasis-like mouse model through further activation of the CCL20‒CCR6 axis.