Superoxide dismutase in alveolar macrophages from patients with diffuse panbronchiolitis

Background: Diffuse panbronchiolitis (DPB) is characterized by chronic neut rophil-mediated inflammation of the airway mediated by oxygen radical produ ction. DPB can be controlled with low-dose and long-term erythromycin thera py based on its anti-inflammatory effect. Objective: In this study, the ant ioxidant levels were analyzed as an anti-inflammatory effect of erythromyci n in the patients. Methods: We investigated the activity and protein level of an antioxidant enzyme, Cu, Zn-superoxide dismutase (SOD) in alveolar mac rophages (AMs) of patients with DPB before and after erythromycin therapy. AMs were obtained from bronchoalveolar lavage fluid. Results: There was no significant difference in the activity of Cu, Zn-SOD between normal subject s and untreated patients. Erythromycin therapy (600 mg/day) significantly i ncreased the activity of the enzyme relative to that before therapy and nor mal subjects [18.2 units/10(6) cells (9.2-26.2) vs. 4.4 units/10(6) cells ( 1.1-9.3), p < 0.01 and 10.4 units/10(6) cells (2.4-20.6), p < 0.05, respect ively]. Furthermore, the protein level of Cu, Zn-SOD in AMs in treated pati ents was significantly higher than in the other two groups [69.4 ng/10(6) c ells (34.2-147.1) vs. 20.1 ng/10(6) cells (16.9-39.8) for untreated patient s, p < 0.01 and 43.2 ng/10(6) cells (32.6-68.2) for normal subjects, p < 0. 01], but the levels Is in the latter groups were not different. Conclusion: Our results suggest that one of the anti-inflammatory effects of erythromy cin in DPB may be, in part, mediated by enhancement of a nti oxidant activi ty in AMs. Copyright (C) 2000 S. Karger AG, Basel.