DUSP8 Overexpression Alleviates LPS-induced Macrophage Inflammatory Responses through JNK/p38 MAPK Pathways / 中国生物化学与分子生物学报

ABSTRACT

Dual-specificity phosphatase 8 (DUSP8) is a member of the dual-specificity phosphatase family, which has been reported to participate in the development of many diseases.However, it is unclear whether DUSP8 plays an important role in the inflammatory response of macrophages and related immune cells.This study aims to detect the expression of DUSP8 in lipopolysaccharide (LPS)-induced macrophage inflammatory responses and to observe the effect of DUSP8 overexpression on macrophage inflammatory responses.100 ng/ml LPS was used to treat bone marrow-derived macrophages (BMDMs) from wild-type C57BL/6 mice at different time points.Real-time PCR and Western blotting results showed that the expression of DUSP8 was significantly reduced in BMDMs (P<0.05) and reached the peak at 12 hours.Next, DUSP8 overexpression vectors (DUSP-EGFP) and control vectors (EGFP) were transfected into BMDM.Data showed that DUSP-EGFP transfection could significantly enhance the expression of DUSP8 in BMDMs (P<0.05).Moreover, FCM data showed that the expressions of CD80 and CD86 markedly decreased in BMDMs with DUSP8 overexpression (P< 0.05).Meanwhile, the neutral red uptake assay data showed that the uptake in DUSP8 overexpression group was lower than that in the control group.Furthermore, ELISA results showed DUSP8 overexpression could significantly reduce the production of IL-1(3 and IL-6 (P < 0.05).Besides, Western blotting results showed that the phosphorylation levels of p38 MAPK and JNK decreased in BMDMs after DUSP8 overexpression (P< 0.05).All together, DUSP8 overexpression could significantly ameliorate LPS-induced macrophage inflammation, which was mainly related to the reduced expression of phosphorylated p38 MAPK and JNK.