Figure 7.

DHEA-mediated activation of 11β-HSD2 involves Akt kinase but not metabolism to 17β-estradiol and testosterone. RCCD2 cells were incubated with tamoxifen (estrogen receptor antagonist; 100 nM) or flutamide (androgen receptor antagonist; 500 nM) in the absence or presence of DHEA for 24 h, followed by determination of 11β-HSD2 activity (A). 11β-HSD2 activity assay in the presence or absence of DHEA and/or 3μM Akt inhibitor. Activities are expressed as percentage of control in the absence of DHEA, which was set to 100% (B). Immunoblot analysis of C/EBP-β, C/EBP-β phosphorylated on Ser¹⁰⁵ (pC/EBP-β), and C/EBP-α. Protein levels are expressed relative to β-actin control protein and normalized to treatment with vehicle, which was set as 1 (C).