IL-36 Cytokine Expression and Its Relationship with p38 MAPK and NF-κB Pathways in Psoriasis Vulgaris Skin Lesions

This study examined the correlation of the expression of interleukin-36 (IL-36), a novel member of interleukin-1 (IL-1) family, with p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-kappa B) pathways in psoriasis vulgaris skin lesions. The expression levels of IL-36 alpha, IL-36 beta, IL-36 gamma, phosphorylated p38 MAPK, and NF-kappa Bp65 were detected in the skin tissues of 38 psoriasis patients and 17 healthy control subjects by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting. The cytokine expression levels were compared between the psoriasis group and the control group. A correlation analysis between cytokine proteins was performed in the psoriasis group. Results showed that the expression levels of IL-36a, IL-36 beta, IL-36 gamma, phosphorylated p38 MAPK and NF-kappa Bp65 in the psoriasis group were significantly higher than those in the control group (P<0.001). In the psoriasis group, the IL-36 cytokine expression was positively correlated with phosphorylated p38 MAPK and NF-kappa Bp65 expression (P<0.05). A significant positive correlation was also found between the phosphorylated p38 MAPK and NF-kappa Bp65 expression (P<0.01). It was concluded that the increased IL-36 expression is correlated with p38 MAPK and NF-kappa B pathways in psoriasis vulgaris skin lesions. All the three factors may be jointly involved in the pathogenesis and local inflammatory response of psoriasis.