Bromodomain and Extraterminal (BET) Protein Inhibition Restores Redox Balance and Inhibits Myofibroblast Activation
Figure 6
Enrichment of Brd2, Brd3, and Brd4 at the NOX4 promoter and their role in TGFβ-induced Nox4 expression. (a) Non-ILD control fibroblasts were starved for 24 h and pretreated with 500 nM JQ1(+) or JQ1(-) for 2 h before stimulation with TGF-β1 (1ng/ml) for further 4 h. Recruitment of Brd2, Brd3, and Brd4 to the NOX4 promoter was determined by ChIP. Data are expressed as fold enrichment compared to the IgG control. Data shown are the mean of two independent experiments performed in two control cell lines. (b) Non-ILD control fibroblasts were either mock-transfected (Control) or transfected with nonspecific siRNA control (negative) or with specific siRNAs to BRD3 (siBrd3) or BRD4 (siBrd4). Cells were stimulated with TGF-β1 for 24 h and the expressions of BRD3, BRD4, or NOX4 mRNA levels were determined by RT-qPCR. The data is presented as the mean ± SEM of independent experiments on four individual cell lines. p<0.01 and p<0.001.