Yu Sun1, Xiaochen Qiu2, Guosheng Wu1, Junjie Wang1, Jiahui Li1, Hao Tang3, Zhaofan Xia4. 1. Department of Burn Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P. R. China. 2. Department of General Surgery, 309th Hospital of PLA, Beijing, P.R. China. 3. Department of Respiratory Medicine, Changzheng Hospital, Second Military Medical University, Shanghai, P. R. China. 4. Department of Burn Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P. R. China. Electronic address: xiazhaofan@163.com.
Abstract
BACKGROUND: Our previous study, consistent with others, demonstrated that administering an exogenous surfactant was a potential therapy for acute lung injury and acute respiratory distress syndrome. However, the underlying mechanisms remain largely unknown. In the present study, we investigated the effect of instilled porcine pulmonary surfactant (PPS) on rat inhalation injury model induced by smoke and the possible mechanism. MATERIALS AND METHODS: Fifteen Sprague-Dawley rats were equally randomized to three groups as follows (n = 5 in each group): sham control group (C group), inhalation injury group (II group), and inhalation injury + PPS treatment group (PPS group). Lung tissues were assayed for wet/dry ratio, histologic, terminal dUTP nick-end labeling staining, and Western blotting examinations. The myeloperoxidase activity was tested in lung tissues as well. Bronchoalveolar lavage fluid was collected to determine the total protein concentrations, inflammatory cytokines, surfactant protein A (SP-A), and SP-D. RESULTS: Our present work exhibited that PPS had therapeutic effects on smoke inhalation injury reflected by significant increase of PaO2 values, improved edema status, decreased vascular permeability, amelioration of lung histopathology, and reduction of inflammatory response. In addition, PPS treatment could increase endogenous SP-A levels both in lung tissue and bronchoalveolar lavage fluid. Further correlation analysis showed that SP-A was negatively correlated with both myeloperoxidase activity and interleukin 8 levels. CONCLUSIONS: These results indicate that PPS can attenuate smoke-induced inhalation injury at least partly through stimulating production of endogenous SP-A and inhibiting the release of proinflammatory cytokines such as interleukin 8. The increasing production of endogenous SP-A may be due to the antioxidant effect of PPS, which contains no SP-A.
BACKGROUND: Our previous study, consistent with others, demonstrated that administering an exogenous surfactant was a potential therapy for acute lung injury and acute respiratory distress syndrome. However, the underlying mechanisms remain largely unknown. In the present study, we investigated the effect of instilled porcine pulmonary surfactant (PPS) on ratinhalation injury model induced by smoke and the possible mechanism. MATERIALS AND METHODS: Fifteen Sprague-Dawley rats were equally randomized to three groups as follows (n = 5 in each group): sham control group (C group), inhalation injury group (II group), and inhalation injury + PPS treatment group (PPS group). Lung tissues were assayed for wet/dry ratio, histologic, terminal dUTP nick-end labeling staining, and Western blotting examinations. The myeloperoxidase activity was tested in lung tissues as well. Bronchoalveolar lavage fluid was collected to determine the total protein concentrations, inflammatory cytokines, surfactant protein A (SP-A), and SP-D. RESULTS: Our present work exhibited that PPS had therapeutic effects on smoke inhalation injury reflected by significant increase of PaO2 values, improved edema status, decreased vascular permeability, amelioration of lung histopathology, and reduction of inflammatory response. In addition, PPS treatment could increase endogenous SP-A levels both in lung tissue and bronchoalveolar lavage fluid. Further correlation analysis showed that SP-A was negatively correlated with both myeloperoxidase activity and interleukin 8 levels. CONCLUSIONS: These results indicate that PPS can attenuate smoke-induced inhalation injury at least partly through stimulating production of endogenous SP-A and inhibiting the release of proinflammatory cytokines such as interleukin 8. The increasing production of endogenous SP-A may be due to the antioxidant effect of PPS, which contains no SP-A.