Blockade of Wnt/β-catenin signaling pathway by DKK1 inhibits paraquat-induced transition of lung fibroblasts / 中华急诊医学杂志

ABSTRACT

Objective:To investigate the effects of inhibition of Wnt/ β-catenin signaling pathway on paraquat (PQ)-induced transition of human lung fibroblast cell line MRC-5 and related molecular mechanisms.Methods:The MRC-5 cells were divided into three groups. Control group without drug treatment; PQ group the cells were treated by PQ (50 μmol/L) for 72 hours to establish cell transition model; PQ+DKK1 group the cells were treated with PQ (50 μmol/L) and DKK1 (10 ng/mL) for 72 hours. Then, the cells were collected, and the transition related signatures including α-SMA, Vimentin and Collagen I were detected by immunofluorescence and Western blot (WB); Meanwhile, the expression levels of Wnt pathway-related molecules including β-catenin, Cyclin D1 and WISP1 were determined by WB, immunofluorescence and real-time fluorescence quantitative PCR (RT-PCR) during the transition; In addition, the inhibitor of Wnt/β-catenin pathway Dickkopf-1 (DKK1) was applied to block the signaling. Then the expression changes of β-catenin, cyclin D1 and WISP1 were detected by WB to verify the inhibitory effect, and the transition marker molecules including α-SMA, Vimentin and Collagen I were also determined by WB.Results:After 72 hours, compared with the Control group, the expression levels of α-SMA, Vimentin and Collagen I of MRC-5 cells in PQ group were increased significantly ( P<0.05); The expression levels of β-catenin, Cyclin D1 and WISP1 of MRC-5 cells in PQ group were significantly up-regulated ( P<0.05); DKK1 could inhibit the high expression of α-SMA, Vimentin and Collagen I of MRC-5 cells during PQ-induced transition ( P<0.05). Conclusions:DKK1 could inhibit PQ-induced transition of lung fibroblasts by interference with Wnt/β-catenin signaling, which was expected to further inhibit pulmonary fibrosis caused by PQ.