Effect of Yiqi Huoxue Formula on pulmonary alveolar-capillary barrier function in the rat of acute lung injury induced by lipopolysaccharide
Objective This study aims to reveal the effects of the Yiqi Huoxue Formula(YQHXF)on the function of the pulmonary alveolar-capillary barrier in rats with acute lipopolysaccharide-induced lung injury and to explore the potential mechanism.Methods Sixty adult male SD rats were randomly assigned to the sham operation,model,dexamethasone(5 mg/kg,gavage),Yiqi Huoxue Formula low-dose(3.6 g/kg,gavage),medium-dose(7.2 g/kg,gavage)and high-dose(14.4 g/kg,gavage)groups.The rats in the sham group received intratracheal instillation of normal saline,and those in other groups received intratracheal instillation of lipopolysaccharide(LPS,5 mg/kg)for the modeling of ALI.The rats in the sham and model groups were administered normal saline by gavage,and those in the other groups were administered the corresponding drugs once a day for 7 days.Specimens were collected 12 h after the last administration.Pathological changes in lung tissue were observed under a light microscope.The wet/dry weight ratio of the lung and the total protein concentration in the bronchoalveolar lavage fluid(BALF)were measured.Immunofluorescence staining was used to measure the protein expression of zonula occludens-1(ZO-1).Western blotting was used to measure protein levels of occludin,aquaporin-1(AQP-1),and AQP-5.Results Compared with the sham group,the model group showed an increased histopathological score of the lung tissue,lung wet/dry weight ratio,and protein concentration in BALF(P<0.01).Yiqi Huoxue Formula medium-and high-dose groups were lower than those in the model group(P<0.05,P<0.01).Compared with the sham group,the model group downregulated the expression of ZO-1,occludin,AQP-1,and AQP-5(P<0.01).Yiqi Huoxue Formula medium-and high-dose groups upregulated the protein levels compared with the model group(P<0.01).Conclusion The findings suggest that the Yiqi Huoxue Formula can improve the dysfunction of the pulmonary alveolar-capillary barrier in the rat model of ALI induced by LPS,and its mechanism is related to regulating tight junction protein(ZO-1,occludin)and aquaporin(AQP-1,AQP-5)expression.