A resveratrol derivative inhibits H1N1 induced inflammation in alveolar epihelial cells. - GreenMedInfo Summary

Airway epithelial cells are the initial sites of influenza virus infection. They participate in the airway inflammatory response by expressing various chemokines such as regulated on activation, normal T cell expressed and secreted (RANTES). In the present investigation, the effects of five stilbenes previously isolated from the roots of Vitis thunbergii on RANTES produced by influenza A virus (H1N1)-infected A549 alveolar epithelial cells were studied. We identified (+)-vitisin A, a tetramer of resveratrol, as a potent agent that inhibits RANTES secretion (EC (50): 0.27 microM). However, resveratrol exhibited a much smaller effect (EC (50): 28.37 microM). H1N1 infection increased the time-dependent phosphorylation of the transcription factor STAT (1) and of Akt (a downstream effector protein of PI3K). When the PI3K-Akt pathway was blocked by wortmannin, H1N1-stimulated STAT (1) phosphorylation and RANTES production were both abrogated, demonstrating that the PI3K-Akt pathway is necessary for STAT (1) activation and RANTES production in A549 cells. Furthermore, H1N1-stimulated phosphorylation of Akt and STAT (1) were also significantly attenuated by (+)-vitisin A. These results suggested that (+)-vitisin A might be a potent anti-inflammatory agent that inhibits influenza A virus-induced RANTES production by interfering with Akt- and STAT (1)-related signal pathways.