Effect of cigarette smoking on Muc1 expression in mouse lung

Abstract

Objective To observe the impacts of cigarette smoking on lung Mucl expression and investigate the relationships between Mucl changes and cigarette smoking stimulations in lung. Methods Male C57 mice were randomly divided into cigarette smoking group （ n = 8） and normal control group （ n = 8）. After the cigarette smoke exposures or not, the mice were sacrificed and the total and differential cell numbers in bronchoalveolar lavage fluid （BALF） were counted. The level of tumor necrosis factor-~ （TNF-a） in BALF was measured. The Mucl level in BALF and lung was determined with ELISA and Western blot respectively. The lung Mucl changes responded to cigarette smoke exposure were confirmed by detecting the MUC1 levels in cultured human lung epithelial A549 cells treated with cigarette smoke extract. Results The higher Mucl level in lung and BALF was found in cigarette smoke exposed mice （P 〈0.05）, accompanied with increases on total cell numbers, neutrophils and macrophages numbers and the level of TNF-a in bronchoalveolar lavage fluid （ P 〈0.05 or P〈0.01）. Furthermore, the MUC1 level was upregulated in the cigarette smoke extract treated A549 cells. Conclusions Cigarette smoking induces lung inflammation with upregulations on MUC1 and TNF-α levels. The Muc1 increase might originate from the stimulation of cigarette smoke to the lung epithelial cells. Key words: Mucl ; Cigarette smoke,Airway inflammation