红霉素对吸烟大鼠肺内TGF-β1和γ-GCS表达的影响

目的： 探讨红霉素对吸烟大鼠肺内转化生长因子-β₁（TGF-β₁）和γ-谷氨酰半胱氨酸合成酶（γ-GCS）的影响以及在慢性阻塞性肺疾病治疗中的抗氧化作用。方法: Wistar大鼠30只，随机抽取20只被动吸烟4周后，10只继续吸烟8周作为吸烟组、10只吸烟加红霉素灌胃作红霉素治疗组，另10只作对照组。测定气道阻力和肺顺应性，采用免疫组织化学法、免疫细胞化学法和原位杂交法检测气道上皮细胞TGF-β₁和γ-GCS蛋白、肺泡巨噬细胞两者蛋白及其mRNA表达。结果: 吸烟组大鼠气道阻力增高，肺顺应性降低，TGF-β₁和γ-GCS蛋白及其mRNA表达均明显增高（P<0.05），红霉素治疗组气道阻力有所降低、肺顺应性增高，TGF-β₁和γ-GCS蛋白及其mRNA表达均低于吸烟组，但高于对照组（P<0.05）。吸烟组TGF-β₁与γ-GCS表达呈正相关（P<0.05），而红霉素治疗组无明显相关性。结论: 红霉素干预后吸烟大鼠肺内TGF-β₁和γ-GCS表达降低，提示红霉素可能在COPD治疗中发挥一定的抗氧化作用。

Effect of erythromycin on transforming growth factor-β1 and γ-glutamylcysteine synthetase in lung of smoking rats

AIM: To investigate the effect of erythromycin on the level of transforming growth factor-β₁ (TGF-β₁) and γ-glutaglutamylcysteine synthetase (γ-GCS) in smoking rats,and to explore the antioxidate therapeutic role of erythromycin in chronic obstructive pulmonary disease.METHODS: Wistar rats were exposed to cigarettes smoking to establish the model.After passive smoking for 4 weeks,erythromycin intragastric intervention was administered continuously for 8 weeks.The expiratory airway resistance and lung compliance were assessed and the expression levels of TGF-β₁ and γ-GCS proteins (and the mRNA) in airway endothelial cells and alveolar macrophages were observed respectively by immunohistochemical,immunocytochemical and (in situ) hybridization.RESULTS: The expiratory airway resistance was increased and the lung compliance was degraded significantly in smoking group and erythromycin group,compared to control group.In erythromycin group,the airway resistance was lower and the lung compliance was higher than that in smoking group (P<0.05).The levels of TGF-β₁ and γ-GCS in smoking group and erythromycin group was obviously increased in airway endothelial cells and alveolar macrophages in comparison with control group (P<0.05).The levels of TGF-β₁ and γ-GCS were inhibited by erythromycin (P<0.05).TGF-β₁ was obviously positive correlated with γ-GCS in smoking group,but this was not found in erythromycin group.CONCLUSION: Erythromycin therapy improves pulmonary function and relieves emphysema change induced by smoking in rats,and decreases the expression of TGF-β₁ and γ-GCS in alveolar macrophages and airway endothelial cells,suggesting that erythromycin may play a role in the antioxidate therapeutic in COPD.