Yu-Feng Wan1, Zu-Hu Huang2, Ke Jing3, Jun Li3, Yi Wang4, Chuan-Qin Xu4, Jian-Hui Chen4, Yu-Long Zheng4. 1. Department of Infectious Diseases, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, People's Republic of China. Department of Respiratory Diseases, Affiliated Huai'an Hospital of Xuzhou Medical College, Huaian 223002, People's Republic of China. 2. Department of Infectious Diseases, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, People's Republic of China. huangzh@jswst.gov.cn. 3. Department of Infectious Diseases, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, People's Republic of China. 4. Department of Respiratory Diseases, Affiliated Huai'an Hospital of Xuzhou Medical College, Huaian 223002, People's Republic of China.
Abstract
INTRODUCTION: The role of inflammation and immunity in COPD treatment is increasingly being recognized. The relationship between anti-inflammation/immunoregulation and emphysema in COPD lungs remains to be elucidated. The aim of this study was to investigate the effects of azithromycin (Azm) on the development of emphysema in smoking-induced COPD in rats. METHODS: Sprague-Dawley rats (n = 50) were randomly assigned to normal, COPD, saline-treated, Azm-treated, and levofloxacin-treated (Lev) groups. The effects of treatment were assessed by measuring the levels of vascular endothelial growth factor (VEGF) by enzyme-linked immunosorbent assay and measuring the numbers of neutrophil and macrophage in bronchoalveolar lavage fluid, vascular endothelial growth factor (VEGF) and VEGF receptor-2 (VEGFR2) protein expression by western blotting. Lung function measurements and histopathological evaluations (mean linear intercept and destructive index) were performed. RESULTS: FEV0.3/FVC and peak expiratory flow were lower in the COPD group than in the normal group. Mean linear intercept and destructive index were lower in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. The numbers of neutrophil and macrophage in bronchoalveolar lavage fluid were lower in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. As confirmed by western blotting, the levels of VEGF in lung homogenates were higher in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. VEGFR2 protein expression was higher in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. CONCLUSIONS: Azm attenuates pulmonary emphysema by partly reversing the decrease in the numbers of inflammatory cells (neutrophil and macrophage) and VEGF secretion and VEGFR2 protein expression in smoking-induced COPD in rats.
INTRODUCTION: The role of inflammation and immunity in COPD treatment is increasingly being recognized. The relationship between anti-inflammation/immunoregulation and emphysema in COPD lungs remains to be elucidated. The aim of this study was to investigate the effects of azithromycin (Azm) on the development of emphysema in smoking-induced COPD in rats. METHODS:Sprague-Dawley rats (n = 50) were randomly assigned to normal, COPD, saline-treated, Azm-treated, and levofloxacin-treated (Lev) groups. The effects of treatment were assessed by measuring the levels of vascular endothelial growth factor (VEGF) by enzyme-linked immunosorbent assay and measuring the numbers of neutrophil and macrophage in bronchoalveolar lavage fluid, vascular endothelial growth factor (VEGF) and VEGF receptor-2 (VEGFR2) protein expression by western blotting. Lung function measurements and histopathological evaluations (mean linear intercept and destructive index) were performed. RESULTS: FEV0.3/FVC and peak expiratory flow were lower in the COPD group than in the normal group. Mean linear intercept and destructive index were lower in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. The numbers of neutrophil and macrophage in bronchoalveolar lavage fluid were lower in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. As confirmed by western blotting, the levels of VEGF in lung homogenates were higher in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. VEGFR2 protein expression was higher in the Azm-treated group than in the COPD, saline-treated, and Lev-treated groups. CONCLUSIONS:Azm attenuates pulmonary emphysema by partly reversing the decrease in the numbers of inflammatory cells (neutrophil and macrophage) and VEGF secretion and VEGFR2 protein expression in smoking-induced COPD in rats.