The oxidative stress effect of protease inhibitor on PFIB-inhalated acute lung injury in rats

Abstract

Objective To detect the influence of protease inhibitor (Aprotinin) on inflammatory factorsof acute lung injury in rats inhalated perfluoroisobutylene (PFIB). Methods Forty healthy and clean adult male Sprague-Dawley rats were randomly divided into five groups according to the body weight: saline control group (Group A), acute lung injury group (Group B), aprotinin treatment group (5 mg/kg, 15 mg/kg and 30 mg/kg, Group C、D、E), eight rats in each group.The rats in group B、C、D、E were exposed to a homemade head exposure perfluoroisobutylene dynamic inhalation system for 5 minutes.30 minutes later, the rats in each group were intraperitoneally injected with saline or configured different concentrations of aprotinin solution.Ended the experiment after 24 hours later, the rats were sacrificed to obtain bronchoalveolar lavage fluid and lung tissue samples to detect the lung wet weight and lung dry weight ratio (W/D), the bronchoalveolar lavage fluid (BALF) total protein content, the content of superoxide dismutase (SOD) and malondialdehyde (MDA) in lung tissue homogenates, the pathologicalchangesand immunohistochemical examination in lung tissues were also observed under the microscope, the data were statistically analyzed. Results The lung wet-to-dry weight ratio、the content of bronchoalveolar lavage fluid total protein and the cotent of MDA were higher in group B、C、D、E than those in group A, and the results were significantly different(P<0.05). The content of SOD was lower in group B、C、D、E than those in group A, and the result was significantly different(P<0.05). The lung wet-to-dry weight ratio、the content of bronchoalveolar lavage fluid total protein and the cotent of MDA were more decreased in group E than those in group B、C、D, and the results were significantly different(P<0.05). The content of SOD was higher in group E than in group B、C、D, and the result was significantly different(P<0.05). Lung tissue histopathology showed mitigater pulmonary edema、lower inflammatory cell infiltration and the less degree of lung injury in group C、D、E than group B, high-dose group was the most immunohistochemical examination showed, the expression of NF-κB in group C、D、E was significantly lower than that in group B. Conclusions The protease inhibitor aprotinin could reduce acute lung injury by anti-oxidative stress and depressing the inflammatory reacion caused by PFIB inhalation. Key words: Lung injury, acute; Protease inhibitors; Perfluoroisobutylene, PFIB