Figure 5
APEX1 represses aldosterone synthase expression in HAoSMCs. (a) Representative confocal microscopy images of APEX1 protein expression in HAoSMCs following treatment for 24 hours with (Pi) or without (Ctr) phosphate. Images are representative for four independent experiments. APEX1 expression: green labeling, nuclei: blue labeling. Scale bar: 10 μm. (b) Representative original Western blots and arithmetic means ± SEM (n = 5; arbitrary units, a.u.) of normalized nuclear to cytoplasmic APEX1 protein ratio normalized to HDAC2 and α-Tubulin protein in the nuclear fraction and cytoplasmic fraction respectively, in HAoSMCs following treatment for 24 hours with (Pi) or without (Ctr) phosphate. *(p < 0.05) statistically significant vs. control treated HAoSMCs. Arithmetic means ± SEM (a.u.) of CYP11B2, PIT1, CBFA1 and ALPL relative mRNA expression in HAoSMCs silenced for 48 hours with negative control siRNA (Neg.si.) or APEX1 siRNA (APEX1si.) and treated for 24 hours with (Pi) or without (Ctr) phosphate (c, n = 8) or with or without 10 µM spironolactone (Spr) (d, n = 6). *(p < 0.05), **(p < 0.01), ***(p < 0.001) statistically significant vs. Neg.si. silenced HAoSMCs. †(p < 0.05) statistically significant vs. APEX1si. silenced HAoSMCs.
