FIG. 7.

Silencing of endothelial RXRα, PPARα, or PPARγ blunted the inhibition of Ang-II-induced HUAEC RhoA activation and Nox5 expression by the combination of Rosu+Bex at suboptimal concentrations. Cells were transfected with control siRNA (A), RXRα-specific siRNA (B), PPARα-specific siRNA (C), or PPARγ-specific siRNA (D) and stimulated with Ang-II (1 μM; 1 h) at 47 h post-transfection. In some experiments, cells were pretreated with Rosu (10 nM) plus Bex (0.3 μM) 20 h before Ang-II challenge. Quantification of RhoA-GTP activity was determined using a colorimetric G-Lisa RhoA activation assay. Results are the mean±SEM of n=5–7 independent experiments and presented as percentage of control siRNA-transfected cells; **p<0.01 relative to the respective vehicle group, ⁺p<0.05 relative to the respective Ang-II stimulated cells. Following a similar protocol but after stimulation with 1 μM Ang-II for 24 h at 24 h post-transfection, Nox5 expression (E–H) was determined by immunoblotting. Results (mean±SEM of five to six independent experiments) are expressed as fold increase of Nox5:β-actin of control siRNA-transfected cells. Representative blots are shown; **p<0.01 relative to the respective vehicle group, ⁺p<0.05 relative to the respective Ang-II-stimulated cells.