Neutrophil -derived microparticles can induce pathological changes of acute respiratory distress syndrome in rats

Wang Xiang-meng; Xiao Wen-kai; Deng Lie-hua

doi:10.3969/j.issn.1002-1949.2018.01.020

Abstract：Objective To investigate the effect of neutrophil -derived microparticles on the histopathological features of lung tissue in rats . Methods Neutrophils were extracted from the peripheral venous blood of rats and NDMPs were extracted from the neutrophils stimulated with LPS .The NDMPs were qualitatively and quantitatively analyzed by the nanoparticle tracking analyzer .The rats were divided into 3 groups:control group , LPS group and NDMPs group .The rats in control group , LPS group and NDMPs group were given 100 μL saline, LPS (5 mg/kg) and NDMPs (2.0 ×109/kg) respectively by endobronchial injection .The changes of lung histological changes were observed by HE staining, lung wet/dry weight ratio, MPO activity in lung tissue and expression of various inflammatory factors in bronchoalveolar lavage fluid after 24 hours.Results Compared with the control group , HE staining of LPS group and NDMPs group showed a large number of inflammatory infiltration , alveolar and interstitial hemorrhage , edema and other pathological changes;LPS group and NDMPs group lung injury score and lung wet and dry ratio was higher than the control (P<0.05).Lung injury score of NDMPs group was lower than that of LPS group (P<0.01), lung wet and dry ratio of NDMPs group was lower than that of LPS group (P<0.05), MPO activity of lung tissue and cytokines in bronchoalveolar lavage fluid of NDMPs group and LPS group were higher than those of control group ( P <0.01 ).The expression of IL -1βin bronchoalveolar lavage fluid of LPS group was higher than that of the control group (P<0.01).The expression of IL-1βin bronchoalveolar lavage fluid in NDMPs group was higher than that in control group (P <0.05).In NDMPs group, the expression of inflammatory cytokines TNF-α, IL-1βand IL-10 expression were lower than LPS group (P<0.05).Conclusion LPS-induced neutrophil -derived microparticles can cause pathological changes of acute respiratory distress syndrome in rats.