Fig. 6.
Estradiol and progesterone inhibit E. coli-induced NF-κB activation. CBMCs were incubated for 16 h with dexamethasone (10−7 M), estradiol (E; 10−7 M), or progesterone (P; 10−5 M) prior to stimulation with E. coli for 15 or 30 min (A and B) or 2 h (C). (A and B) Total and phosphorylated (p) IκBα (A) and NF-κB p65 (p65) (B) in nuclear (n) and cytosolic (c) extracts were detected by Western blotting. Densitometric values (means of 3 to 6 independent experiments) are expressed relative to expression in untreated CBMCs (set at 1). (C) IκBα mRNA expression was quantified by real-time PCR and normalized to the expression of HPRT. Data represent means ± SEMs of 6 independent determinations. * and **, P < 0.05 versus untreated and E. coli-stimulated CBMCs, respectively. (D) CBMCs were preincubated for 1 h with 10−5 M quinazoline prior to incubation with E. coli for 6 h. TNF concentrations in cell culture supernatants were measured by bioassay. Data represent means ± SEMs of 4 independent experiments performed in triplicate. *, P < 0.05.