Abstract: | PROBLEM: In vivo and in vitro studies have indicated that estradiol can affect cytokine production in different cell types. This study examines whether estradiol affects inflammatory cytokine production by murine splenic macrophages. METHODS: Mouse splenic macrophages were first treated with 17β-estradiol, followed by lipopolysaccharide (LPS) stimulation. The production of cytokines by macrophages with or without estradiol treatment was determined at both the protein and mRNA levels. The nuclear factor-kB (NFkB) activity of activated mouse splenic macrophages was also evaluated by electrophoretic mobility shift assay. RESULT: Our results show that 17β-estradiol decreases LPS-induced IL-1α, IL-6, and TNF-α production but not IL-10, IL-12, and macrophage inflammatory protein (MIP) production by splenic macrophages. Furthermore, inhibition of cytokine production by 17β-estradiol was associated with a decreased LPS-induced NFkB-binding activity. CONCLUSION: Because cytokines are important mediators of immune function, the alteration of cytokine production by 17β-estradiol may thus have a profound effect on the outcome of immune response during inflammation. |