Effect of refloated soil dust on oxidative stress and apoptosis in rat lung

Abstract

Little study has illustrated the associations between inhalation of refloated soil dust and the morbidity of respiratory disease in animals. In this study, soil dust samples in arid and semiarid areas of China were collected for investigating the underlying biotoxicity and mechanisms of oxidative stress and apoptosis in rat lung induced by inhalation of refloated soil dust. The soil dust samples were collected from the arid and semiarid areas in Zhangjiakou city, located close to Inner Mongolia Plateau, China. After intratracheal instillation of soil dust, superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities in rat lung were declined in a dose-dependent relationship, and pathology changes in lung tissue were also enhanced along with increased levels of soil dust. Meanwhile, apoptotic cells were scattered in the pulmonary epithelial and distributed in the mesenchyma, and the apoptotic index was significantly increased in rat lung instilled by soil dust. Besides, soil dust promoted Bax expression and inhibited Bcl2 expression, i.e., increased Bax/Bcl2 ratio in a concentration-dependent manner. In summary, short-term exposure to soil dust caused oxidative damage and induced apoptosis in rat lung through the regulation of Bax and Bcl2 expression.