Background: Ginseng (Panax ginseng C.A. Meyer) has been used in Asian countries for the treatment of various diseases. However, the mechanisms of liquid Panax ginseng (LG) on allergic inflammatory response in epidermal growth factor (EGF)-stimulated human airway epithelial cells remain largely unclear.
Methods: MUC5AC, cyclooxygenase (COX) 2, and matrix metalloproteinase (MMP) 9 expressions were measured using reverse transcription-polymerase chain reaction, Western blotting, and gelatin zymogram analyses in NCI-H292 cells. Extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) protein levels were analyzed by Western blotting.
Results: To gain insight into the antiallergy effects of LG, we examined its influence on epidermal growth factor (EGF)-induced MMP-9 and COX-2 productions in NCI-H292 cells. LG was treated for 1 hour and then followed by EGF treatment for 24 hours into NCI-H292 cells. The decrease of COX-2 production was correlated with the reduced levels of proteins and mRNAs of inducible MMP-9 and MUC5AC. LG blocked upstream signaling of NF-kappa-B activation via inhibition of phosphorylations of inhibitor factor-kappa- B-alpha (I-kappa-B-alpha) and ERK. These results suggest that LG protects NCI-H292 cells from EGF-induced damage by down-regulation of COX-2, MMP-9, and MUC5AC gene expressions by blocking NF-kappa-B and ERK.
Conclusion: LG modulates allergic inflammatory response in EGF-stimulated NCI-H292 human airway epithelial cells via inhibition of I-kappa-B-alpha and ERK.