Objective: To explore the protective effects and mechanism of ethanol extract of Inonotus obliquus (EEIO) injection on asthmatic mice.
Method: OVA was injected intraperitoneally and inhaled to produce the asthmatic model. Thirty two mice were randomly divided into four groups: control group, asthma group and I. obliquus groups of high and low dose. The concentrations of IL-4, IL-5, IL-13 and IFN-gamma in BALF, the phosphor-p38 MAPK in lung tissues were respectively measured by ELISA and Western blotting. The number of inflammatory cells in BALF and histopathology changes were observed.
Result: In asthmatic group, the number of inflammatory cells and the concentrations of IL-4, IL-5, IL-13 in BALF and phospho-p38 MAPK in lung tissue were higher, while IFN-gamma were lower than those in normal control mice (P < 0.05). In I. obliquus group, the number of inflammatory cells, the concentrations of IL-4, IL-5, IL-13 in BALF and phosphor-p38 MAPK in lung tissue were lower, but were higher than those in normal control mice (P < 0.05), and histropathology damage was alleviated significantly. There was no significant difference observed among the efficacies in the I. obliquus groups of high and low dose.
Conclusion: p38 MAPK may play a role in pathological process of asthma. I. obliquus effectively treats asthma by inhibiting the expression of phosphor-p38 MAPK, correcting the unbalance of IFN-gamma/IL-4 and decreasing the number of inflammatory cells.