Lysophosphatidylcholine facilitates the pathogenesis of psoriasis through activating keratinocytes and T cells differentiation via glycolysis.

Abstract

Although abnormal metabolism plays a critical role in the pathogenesis of psoriasis, the details are unclear. Here, we identified to explore the role and mechanism of lysophosphatidylcholine (LPC) on the pathogenesis of psoriasis. The level of LPC in plasma and skin lesions and the expression of G2A on skin lesions of psoriasis patients were detected by enzyme-linked immunosorbent assay, liquid chromatography-tandem mass spectrometry, or immunohistochemistry, respectively. The glycolysis in the skin lesions of imiquimod (IMQ)-induced psoriasis-like mouse model was detected by extracellular acidification rate. LPC was subcutaneously injected into IMQ-treated mouse ears, and the phenotype as well as the glycolysis were evaluated. Exploring the effects and mechanism of LPC on keratinocytes and CD4+ T cells by culturing primary keratinocytes and CD4+ T in vitro. We found that LPC was significantly increased both in the plasma and skin lesions of psoriatic patients, while G2A, exerting an essential role in LPC-inducing biological functions, was increased in psoriatic lesions. The abundance of LPC was positively correlated with glycolytic activity in the psoriasis-like mouse model. LPC treatment facilitated psoriasis-like inflammation and glycolytic activity in skin lesions. Mechanistically, the LPC/G2A axis significantly triggered glycolytic activity and produced inflammatory factors in keratinocytes, and blockade of glycolysis abrogated LPC-induced expression of inflammatory mediators in keratinocytes. LPC activated STAT1, resulting in recognition and binding to the promoters of GCK and PKLR, which are glycolytic rate-limiting enzymes. Furthermore, the LPC/G2A axis directly benefited Th1 differentiation, which was dependent on LPC-induced glycolytic activity. Notably, LPC indirectly facilitated Th17 differentiation by inducing the secretion of IL-1β in keratinocytes-T cells coculture system. Taken together, our findings revealed the role of the LPC/G2A axis in the pathogenesis of psoriasis; targeting LPC/G2A is a potential strategy for psoriasis therapy.