Kinetics of nuclear factor ?B in LPS stimulated rat alveolar macrophages and its regulative effect on tumor necrosis factor ? expression / 中华创伤杂志

ABSTRACT

Objective To investigate the activation of nuclear factor ?B (NF-?B) induced by lipopolysaccharides (LPS) in rat alveolar macrophages (AM) and its regulative role in tumor necrosis factor (TNF-?) expression. Methods The dynamic activity changes of NF-?B DNA induced by LPS (E.coli 026B6) were determined with electrophoretic mobility shift assay (EMSA). The phosphorothioate oligodeoxynucleotides (S-ODN) decoy was transfected into AM 12 hours prior to LPS stimulation. The effect of NF-?B S-ODN decoy on expression of TNF-? in AM stimulated by LPS were measured with enzyme-linked immunosorbent assay (ELISA) kit. Results NF-?B could be activated remarkably after 0.5 hour of LPS stimulation at concentration of 100 ng/ml, reached the highest level 1 hour after LPS stimulation and gradually decreased. But the activation of NF-?B could last at least 8 hours. The dose for LPS stimulation was related to activation of NF-?B in a dose-dependent fashion, ie, the activation of NF-?B gradually strengthened with dose increase of LPS. Supershift assays proved that p50 and p65 were involved in the activation of NF-?B. NF-?B S-ODN decoy could markedly (not completely) inhibit LPS-induced TNF-? production. Conclusions NF-?B plays an important role in LPS induced inflammatory response. However, entire inhibition of the activity of NF-?B can not completely prevent TNF-? expression induced by LPS in rat AM, which implies that other nuclear factors may participate in TNF-? expression.