【作者】 毛新妍；

【导师】 顾振纶； 蒋小岗；

【作者基本信息】 苏州大学 ， 药理学， 2013， 硕士

【摘要】 目的观察吲哚-3-原醇（Indole-3-carbinol，I3C）对博莱霉素（Bleomycin, BLM）致小鼠和大鼠肺纤维化的干预作用并初步探讨其机制。方法ICR小鼠随机分为6组：正常组、模型组、醋酸泼尼松组(6.67mg·kg^-1)、I3C小、中、大剂量组(25、50、100mg·kg^-1)；SD大鼠随机分为6组：正常组、模型组、醋酸泼尼松组(3.34mg·kg^-1)、I3C小、中、大剂量组(12.5、25、50mg·kg^-1)。通过气管内注射BLM制备肺纤维化模型，造模后第二天治疗组动物分别给予泼尼松和不同剂量的I3C，每天一次。连续给药28天处死动物，称其体重、计算肺系数；紫外分光光度计检测血清和肺组织羟脯氨酸（Hydroxyproline，HYP）含量、血清和肺组织总抗氧化能力（Total antioxidative capacity，T-AOC）水平；取固定部位肺组织切片HE和Masson染色，光镜下进行病理学观察；电镜观察大鼠肺组织超微结构变化；ELISA法检测大鼠肺泡灌洗液中IL-1β和IL-6的含量；RT-PCR法检测肺组织中α-SMA、Collagen I、TGF-β1、Smad2、Smad7mRNA的表达；Real Time RT-PCR法检测大鼠肺组织miRNA-21、Let-7d的表达；Western blot法检测肺组织中α-SMA、Vimentin、Caveolin-1、TGF-β1、Smad2蛋白的表达。结果I3C给药28天后，肺纤维化小鼠/大鼠的血清和肺组织T-AOC水平明显提高（P<0.05，P<0.01），肺系数、血清和肺组织HYP含量明显降低（P<0.05，P<0.01）；I3C组大鼠肺泡灌洗液中IL-1β和IL-6的含量明显降低（P<0.05，P<0.01）；光镜观察表明I3C组肺纤维化小鼠/大鼠肺泡炎和肺纤维化程度明显降低（P<0.05，P<0.01）；RT-PCR检测发现I3C组肺组织α-SMA、Collagen I、TGF-β1、Smad2基因水平明显下调， Smad7基因表达明显上调（P<0.05，P<0.01）；Real Time RT-PCR检测发现I3C组大鼠miRNA-21表达明显下调，Let-7d的表达明显上调（P<0.05，P<0.01）；Western blot分析结果表明I3C组小鼠/大鼠肺组织α-SMA、Vimentin、TGF-β1、Smad2蛋白表达明显下调（P<0.05，P<0.01），Caveolin-1蛋白表达上调。结论I3C对BLM致肺纤维化小鼠/大鼠可提高机体总抗氧化能力、减少炎症因子产生、减少细胞间质胶原沉积，具有一定的抗肺纤维化作用，该作用机制可能与其调控TGF-β1/Smad信号通路有关。更多还原

【Abstract】 Objective: To investigate the effects and mechanisms of indole-3-carbinol （I3C） onbleomycin-induced pulmonary fibrosis in mice and rats.Methods: The ICR mice were divided into six groups randomly：control group, modelgroup, prednisolone group(6.67mg·kg^-1) and I3C low-dose (25mg·kg^-1), middle-dose (50mg·kg^-1), high-dose group (100mg·kg^-1). The SD rats were divided into six groupsrandomly：control group, model group, prednisolone group (3.34mg·kg^-1) and I3Clow-dose (12.5mg·kg^-1), middle-dose (25mg·kg^-1), high-dose group (50mg·kg^-1).Pulmonary fibrosis model was replicated by single intratracheal injection of bleomycin. Inthe next day, the animals were treated by intragastric administration once a day. After28days, the animals were sacrificed. The lung index and the levels of T-AOC and HYP weremeasured, and the pathologic changes of the lung tissue were obtained by HE and Massonstaining. The levels of IL-1β and IL-6in bronchoalveolar lavage fluid were assayed byELISA. The levels of α-SMA, Collagen I, TGF-β1, Smad2and Smad7mRNA wereassayed by RT-PCR. The levels of miRNA-21and Let-7d were assayed by Real TimeRT-PCR. The levels of α-SMA, Vimentin, Caveolin-1, TGF-β1and Smad2protein wereanalyzed by western blot.Results: I3C improved the activity of T-AOC in serum, and reduced pulmonary indexand the content of HYP as well（P<0.05or P<0.01）; the alveolitis and fibrosis extent wereattenuated significantly（P<0.05or P<0.01）; the levels of IL-1β and IL-6inbronchoalveolar lavage fluid were decreased significantly; the levels of TGF-β1, Smad2,Vimentin, α-SMA and Collagen I were all decreased significantly（P<0.05or P<0.01）;thelevels of Caveolin-1and Smad7were all increased significantly（P<0.05or P<0.01）; thelevel of miRNA-21was decreased significantly, while the level of Let-7d was increasedremarkably（P<0.05or P<0.01）.Conclusion: I3C could attenuate bleomycin-induced pulmonary fibrosis in mice and rats. The mechanisms might be related with the anti-oxidatant, the anti-inflammatory,inhibition of collagen formation and the regulation of TGF-β1/Smad signal pathway.更多还原