Tetrandrine inhibits signal-induced NF-kB activation in rat alveolar macrophages.
Chen F; Sun S; Kuhn DC; Lu Y; Gaydos LJ; Shi X; Demers LM
Biochem Biophys Res Commun 1997 Feb; 231(1):99-102
Tetrandrine is a bisbenzylisoquinoline alkaloid isolated from a natural Chinese herbal medicine. While this alkaloid has been shown to exhibit antifibrotic and anti-inflammatory activities, its mechanism of action is unknown. The present study was designed to investigate the inhibitory effect of tetrandrine on NF-kB activation in the alveolar macrophage. Three different provocative stimuli were used to activate NF-kB in these cells. The results indicate that tetrandrine can inhibit the activation of NF-kB and NF-kB-dependent reporter gene expression by LPS, PMA, and silica in a dose-dependent manner. In contrast, at the doses used, tetrandrine did not interfere with Sp-1 DNA binding activity or Sp-1-dependent reporter gene expression in these cells. Western blot analysis suggests that the inhibitory effect of tetrandrine on NF-kB activation can be attributed to its ability to suppress signal-induced degradation of IkBa, a cytoplasmic inhibitor of the NF-kB transcription factor.
Medicinal-chemicals; Alveolar-cells; Cellular-reactions; Cell-function; Physiological-effects; Physiological-factors; Diseases; Disease-prevention
F. Chen, Department of Pathology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, 17033
Biochemical and Biophysical Research Communications