The role of MicroRNA-23a in apoptosis of alveolar septal cells in rats with autoimmune emphysema
Objective:To investigate the effect of microRNA-23a(miRNA-23a)on the apoptosis of alveolar septal cells in rats with autoimmune emphysema.Methods:Twenty-four male SD rats were randomly divided into the emphysema group,nor-mal control group and miRNA-23a agomir intervention group.The emphysema group was treated with intrabitoneal injection of hu-man umbilical vein endothelial cells and complete Fredrin adjuvant+the same volume of normal saline was injected into the tail vein on the same day as the miRNA-23a agomir intervention group;for miRNA-23a agomir intervention group,on the same day as the emphysema group,+miRNA-23a agomir(25 μM)was injected through the tail vein at 1,7,14 and 21 days after the model-ing,respectively;The normal control group was intraperitoneally injected with the same dose of complete Freund's adjuvant+the same volume of normal saline was injected through the tail vein on the same day.21 days after modeling,hematoxylin-eosin staining was performed on the right lower lung of all rats and pathological changes were observed,mean alveolar number(MAN)and mean linear interce-pt(MLI)were measured.The expression level of miRNA-23a was detected by Quantitative real-time polymerase chain reaction in the right upper lung.Terminal deoxynucleotidyl transferaseme-diated dUTP nick end labeling method detected apoptotic alveolar septal cells and calculated apoptotic index(AI).Serum concentrations of antiendothelial cell antibodies(AECA)were detected.Results:(1)The pathological changes of pulmonary emphysema in the three groups were as follows:normal control group<miRNA-23a agomir intervention group<emphysema group;(2)Comparison of MAN and MLI among the three groups:MAN comparison:normal control group>miRNA-23a agomir intervention group>emphysema group,with statistical signifi-cance among all groups(all P<0.01).MLI comparison:normal control group<miRNA-23a agomir intervention group<emphy-sema group,with statistical significance among all groups(all P<0.01);(3)Comparison of serum AECA concentration in three groups:normal control group<miRNA-23a agomir intervention group<emphysema group,with statistical significance among all groups(all P<0.01);(4)Comparison of miRNA-23a in lung tissue of three groups of rats:normal control group>miRNA-23a agomir intervention group>emphysema group,with statistical significance among all groups(all P<0.01);(5)Three groups of rat alveolar septal cell apoptosis number comparison:normal control group<miRNA-23a agomir intervention group<emphy-sema group,with statistical significance among all groups(all P<0.01).Conclusion:The down-regulated expression of miRNA-23a was involved in the apoptosis of alveolar septal cells in emphysema model rats.miRNA-23a agomir can reduce the apoptosis of alveolar septal cells in emphysema model rats,thereby delaying the progression of autoimmune emphysema disease.