Objective To investigate the possible mechanism of traditional Korean medicine Mahuang Dingchuan Decoction（ 麻黄定喘汤） in treating bronchial asthma. Methods A total of 40 BABL/c mice were randomly divided into blank group

model group

Mahuang Dingchuan Decoction low dose group and high dose group

with 10 mice in each group. Except the blank group

asthma models were established by sensitization and challenge with ovalbumin（ OVA）. The low dose group was given 4 ml/100 g Mahuang Dingchuan Decoction（ concentration 20 mg/ml） daily by gavage

and the high dose group was given 12 ml/100 g Mahuang Dingchuan Decoction daily by gavage.The mice in the blank group and the model group were given intraperitoneal injection of 0. 9% sodium chloride solution for a total of 8 weeks. The brocho-alveolar larage fluid（ BALF） and lung tissue were collected 24 h after the last challenge. The pathological changes were observed. The contents of inflammatory cytokines

reactive oxygen species（ ROS）

malondialdehyde（ MDA） content

superoxide dismutase（ SOD）

and catalase（ CAT） activity in the BALF were detected. The phosphorylation of p38 nuclear mitogen-activated protein kinase（ p-p38 MAPK）

nuclear factor E2 related factor（ Nrf2）

heme oxygenase 1（ HO-1） levels in the lung tissue were detected by Western Blot.Results Compared with the blank group

the inflammatory cells count

neutrophils and eosinophils

ROS and MDA in the BALF

p-p38 MAPK

Nrf2

HO-1 protein levels and the expression level of Nrf2

HO-1 mRNA in lung tissue of the model group were significantly increased

and SOD and CAT activities were significantly decreased（ P <0. 05）. Compared with the model group

the inflammatory cells count

neutrophils and eosinophils in BALF of the high-and low-dose group were significantly decreased. The levels of ROS

MDA in the BALF

the level of p-p38 MAPK protein in lung tissue decreased. The activity of SOD and CAT in BALF and the expression of Nrf2 and HO-1 protein in lung tissue

and the expression of Nrf2 and HO-1 mRNA increased（ P < 0. 05）. Compared with the low dose group of Mahuang Dingchuan Decoction

the inflammatory cells count

neutrophils

eosinophils

ROS and MDA in BALF

p-p38 MAPK level in lung tissue of high dose group of Mahuang Dingchuan Decoction group was significantly reduced

and SOD CAT activity and Nrf2

HO-1 protein and mRNA expression were increased（ P < 0. 05）.Conclusion Traditional Korean medicine Mahuang Dingchuan Decoction can inhibit the airway inflammation in mice with bronchial asthma

of which affecting p38 MAPK/Nrf2/HO-1 signaling pathways by anti-oxidation might be one of the mechanisms.