Knockdown of nrf2 Exacerbates TNF-α-Induced Proliferation and Invasion of Rheumatoid Arthritis Fibroblast-Like Synoviocytes through Activating JNK Pathway

Figure 6

JNK pathway mediates the modulation of proliferation, invasion, and MMP9 expression in RA-FLS by nrf2. (a) After transfection with scramble siRNA or nrf2 siRNA for 3 days, RA-FLS were further stimulated with/without TNF-α (25 ng/mL) for 24 h. Representative figures show the phosphorylation of ERK examined by Western blotting. β-Tubulin was used as the housekeeping gene. (b) Representative figures show the phosphorylation of JNK examined by Western blotting. GAPDH was used as the housekeeping gene. (c) After transfection with nrf2 siRNA for 3 days, the proliferation of RA-FLS was analyzed by CCK-8 assay. Cells were cultured in the 96-well plate and stimulated with TNF-α (25 ng/mL) in the presence or absence of SP600125 (20 μM) for 4 days. (d, e) After transfection with nrf2 siRNA for 3 days, invasion of RA-FLS was analyzed with transwell assay. Cells were cultured in the transwell chamber and stimulated with TNF-α (25 ng/mL) in the presence or absence of SP600125 (20 μM) for 2 days. (f) After transfection with nrf2 siRNA for 3 days, RA-FLS were further stimulated with TNF-α (25 ng/mL) in the presence or absence of SP600125 (20 μM) for 24 h. The MMP9 mRNA expression was examined by real-time PCR. Scale bar represented 200 μm. . Data were shown as the ; .

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