Protective Effect of Astragali on LPS-induced Acute Lung Injury

Objective: To observe the pulmonary injury ,apoptosis of pulmonary epithelium and the protective effect of astragali on lipopo-lysaccharide(LPS)-induced acute lung injury(ALI) in rats. Methods: The rats were randomly divided into three groups: control group, ALI group, astragali group. The respiratory rate, partial pressure of arterial oxygen, and the ratio of W/D were detected. TNF-α and IL-1βin blood plasma were measured, Pulmonary histopathological examinations were performed by electron microscope, apoptosis of pulmonary epithelium was detected by TUNNEL using immunocytochemistry in all groups. Results; Partial pressure of arterial oxygen in ALI group was lower significantly than that in control group. The respiratory rate, the ratio of W/D, the levels of serum TNF-αand IL-1βin ALI group were all significantly higher than those in control group. The PMNs infiltration in ALI group was more than that in control group and the integrity of the alveolus epithelium in ALI group was destroyed. TUNNEL-positive cells in ALI group were more than those in control group. In astragali group, partial pressure of arterial oxygen was higher significantly than that in ALI group. The respiratory rate, the ratio of W/D, the levels of serum TNF-αand IL-1βin ALI group were all significantly lower than those in ALI group. The PMNs infiltration was less than that in ALI group. TUNNEL-positive cells were less than those in ALI group. Conclusion; After administration of astragali, the symptoms of respiratory distress were reduced, the infiltration of PMN in pulmonary tissue and pulmonary edema were decreased, the release of TNF-αand IL-1β in blood plasma were reduced,the apoptosis of the pulmonary epithelium was inhibited. These suggest that astragali may have protective effects on LPS-induced ALI in rats.