扁蒴藤素对肺纤维化模型小鼠肺组织形态及转化生长因子-β1、α-平滑肌肌动蛋白表达的影响

Effects of Pristimerin on Morphology of Lung Tissue and Expressions of TGF-β1 andα-SMA of Pulmonary Fibrosis Model Mice

目的观察扁蒴藤素对肺纤维化模型小鼠肺组织形态及转化生长因子(TGF)-β1、α-平滑肌肌动蛋白(α-SMA)表达的影响,探讨其作用机制。方法采用气管内注射博来霉素溶液制备小鼠肺纤维化模型。将32只雄性C57BL/6J小鼠随机分为正常组、模型组、扁蒴藤素组及吡非尼酮组,每组8只。正常组和模型组给予等量生理盐水腹腔注射,扁蒴藤素组给予1 mg/kg扁蒴藤素溶液腹腔注射,吡非尼酮组给予50 mg/kg吡非尼酮溶液腹腔注射。给药体积10 mL/kg,每日1次,连续28 d。取肺组织行HE及Masson染色,评估小鼠肺组织病理学变化及胶原沉积;免疫组化和Western bot检测小鼠肺组织TGF-β1及α-SMA蛋白的表达。结果HE及Masson染色显示,扁蒴藤素组小鼠肺泡炎及肺纤维化评分低于模型组(P<0.05,P<0.01);免疫组化及Western blot结果显示,与正常组比较,模型组小鼠TGF-β1及α-SMA蛋白表达明显升高;与模型组比较,扁蒴藤素组和吡非尼酮组小鼠肺组织TGF-β1及α-SMA蛋白表达显著下降(P<0.05,P<0.01)。结论扁蒴藤素可改善模型小鼠肺纤维化,其机制可能与抑制TGF-β1及α-SMA蛋白表达有关。

Objective To explore the effects of pristimerin on Morphology of lung tissue and the expressions of TGF-β1 andα-SMA of pulmonary fibrosis model mice;To explore the action mechanism.Methods A mouse lung fibrosis model was prepared by intratracheal injection of bleomycin solution.32 male C57BL/6J mice were randomly divided into control group,model group,pristimerin group and pirfenidone group,with 8 mice in each group.The control and model groups were given the same amount of saline by intraperitoneal injection;the pristimerin group was given 1 mg/kg pristimerin by intraperitoneal injection,and the pirfenidone group was given 50 mg/kg pirfenidone by intraperitoneal injection.The administration volume was 10 mL/kg once a day for 28 consecutive days.Lung tissues were obtained by HE and Masson staining to evaluate the pathological changes and collagen deposition in the lung tissues of mice.Immunohistochemistry and Western blot were used to determine the expressions of TGF-β1 andα-SMA proteins in the lung tissues of mice.Results HE staining and Masson staining showed that alveolar inflammation and pulmonary fiber score in mice of pristimerin group were significantly lower than the model group(P<0.05,P<0.01).The results of immunohistochemistry and Western blot showed that compared with the control group,the protein expressions of TGF-β1 andα-SMA in the model group significantly increased;Compared with the model group,the protein expressions of TGF-β1 andα-SMA in the lung tissues of mice in the pristimerin group and pirfenidone group were significantly reduced(P<0.05,P<0.01).Conclusion Pristimerin can relieve bleomycininduced pulmonary fibrosis in mice,and the mechanism may be related to the down-regulation of protein expressions of TGF-β1 andα-SMA.