Fig. 4.

Inhibitory effects of 17β-estradiol (E2) on the expression of nuclear factor κB (NF-κB)-dependent inflammatory mediators in azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis in mice. (A) AOM/DSS-induced Krüppel-like factor 4 (KLF4) mRNA expression was inhibited by E2. Expression of KLF4 in the colonic mucosa was measured by qRT-PCR analysis. (B) AOM/DSS-induced NF-κB activation was reduced by E2. Expression of NF-κB in the nuclear fraction within the colonic mucosa was assessed by western blot analysis. (C) AOM/DSS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression was diminished by E2. Expression of iNOS and COX-2 was measured by Western blot analysis. (D–F) Expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β in the colonic mucosa was detected by qRT-PCR analysis. (G, H) Expression of estrogen receptor (ER)α and ERβ in the colonic mucosa was detected by qRT-PCR analysis. GAPDH, Lamin B, and β-actin expression were used as internal controls to normalize expression.

pRT-PCR, quantitative real-time polymerase chain reaction; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; M_Con., male control mice; M_ AOM/DSS, male mice treated with AOM/DSS; M_AOM/DSS/E2, AOM/DSS-treated male mice administered estradiol; F_Con., female control mice; F_AOM/DSS, female mice treated with AOM/DSS. *p<0.05 for comparison between two groups.