NFκB inhibitor and siP65 abolished the inhibitory effect of GENT on inflammatory cytokine production by PEMs and BMMs induced by LPS/IFN-γ. (A,B,C) BMMs were treated with 5 µM NFκB inhibitor (BAY117082) for 1 h, followed by GENT (1,000 ng/mL) for 3 h and LPS/IFN-γ for another 6 hours. The mRNA levels of IL-1β, IL-6 and iNOS of BMM were determined by qPCR. (D,E,F) PEMs were transfected with siP65#1 and siP65#2 for 48 h, followed by GENT (1,000 ng/mL) for 3 h and LPS/IFN-γ for another 6 hours. The mRNA levels of IL-1β, IL-6 and iNOS of PEM were determined by qPCR. (G) PEMs were transfected with siP65#1 and siP65#2 for 48 h. The inhibitory efficiency of two siRNAs for P65, siP65#1 and siP65#2, in PEMs was determined by qPCR. Error bars represent the mean ± SEM, and all experiments were repeated at least three times. * indicates P<0.05, NS indicates P>0.05. GENT, gentiopicroside; LPS, lipopolysaccharide; IFN, interferon; PEM, peritoneal elucidated macrophage; BMM, bone marrow-derived macrophage.