Effects of evodiamine on inflammation and apoptosis of airway epithelial cells in asthma model rats and its mechanism / 中国药房

ABSTRACT

OBJECTIVE To explore the effects and potential mechanism of evodiamine on inflammatory response and apoptosis of epithelial cells in asthma model rats. METHODS SD rats were separated into control group， model group， evodiamine low-dose group （10 mg/kg）， evodiamine high-dose group （20 mg/kg）， dexamethasone group （positive control， 0.5 mg/kg）， epidermal growth factor （EGF） group [mitogen-activated protein kinase （MAPK） activator， 10 μg]， evodiamine high-dose+EGF group （20 mg/kg evodiamine+10 μg EGF）， with 10 rats in each group. Except for the control group， the other groups were sensitized by 3-point injection of 10% ovalbumin（OVA）-aluminium hydroxide mixture and stimulated by inhalation of 2%OVA nebulized liquid to establish an asthma model. The count of inflammatory cells （macrophages and lymphocytes） in bronchoalveolar lavage fluid （BALF） was detected in each group； pathological changes of lung tissue in rats were observed； the apoptosis of airway epithelial cells， the levels of serum inflammatory factors [tumor necrosis factor-α， interleukin-6 （IL-6） and IL-4]， the expressions of pathway-related proteins p38 MAPK， phosphorylated p38 MAPK （p-p38 MAPK）， signal transduction and transcription activating factor 1 （STAT1）] and apoptosis-related proteins [B cell lymphoma-2 （Bcl-2） and Bcl-2 associated X protein （Bax）] were all detected in lung tissue. RESULTS Compared with the control group， bronchial mucosal edema， thickening of alveolar septa and extensive infiltration of inflammatory cells were observed in the lung tissue of rats in the model group； the number of inflammatory cells， apoptosis rate of airway epithelial cells， the levels of inflammatory factors， p-38 MAPK/p-38 MAPK， and the protein expressions of Bax and STAT1 were increased significantly； the expressions of Bcl-2 protein and Bcl-2/Bax were reduced significantly （P＜0.05）. Compared with the model group， the pathological changes in lung tissues were alleviated to varying degrees in evodiamine low-dose and high-dose groups， and dexamethasone groups， and the above indicators were significantly reversed. However， the change trends of corresponding indicators in the EGF group were opposite to the above （P＜0.05）. EGF could significantly attenuate the effect of high-dose evodiamine on inflammatory response in asthmatic rats （P＜0.05）. CONCLUSIONS Evodiamine can relieve inflammatory reactions and inhibit the apoptosis of airway epithelial cells in asthmatic rats， the mechanism of which may be associated with inhibiting p38 MAPK/STAT1 signaling pathway.