多聚鸟苷酸干预大鼠矽肺纤维化的内质网应激作用机制  

Polyguanylic acid intervenes silicosis fibrosis in rats through endoplasmic reticulum stress

作　　者：王娜[1] 杨萌 雷素英[3] 千新来[3] 姚三巧[1,2] 

机构地区：[1]新乡医学院公共卫生学院,河南新乡453000 [2]华北理工大学公共卫生学院,河北唐山063000 [3]新乡医学院第三附属医院,453000

出　　处：《中国职业医学》2017年第4期399-407,共9页China Occupational Medicine

基　　金：国家自然科学基金(81273017;81573122);河南省科技攻关项目(162102310491)

摘　　要：目的探讨肌醇需求激酶1(IRE1)介导的内质网应激(ERS)细胞凋亡途径在多聚鸟苷酸(PolyG)干预大鼠矽肺纤维化中的作用及机制。方法将无特定病原体级成年雄性SD大鼠随机分为对照组(24只)、矽肺模型组(24只)、PolyG预防组(16只)和PolyG治疗组(16只),采用一次性吸入式气管滴注法,对照组大鼠予灭菌0.9%氯化钠溶液1 mL,其余3组大鼠均予质量浓度为50.0 g/L的矽尘混悬液1 mL以构建矽肺纤维化大鼠模型。PolyG预防组大鼠于造模当天,PolyG治疗组大鼠于造模第28天,均一次性经尾静脉注射剂量为2.5 mg/kg体质量的PolyG,于PolyG给药后第28和56天各处死大鼠8只。观察各组大鼠肺组织病理改变情况,以免疫印迹法测定葡萄糖调节蛋白-78(GRP78)、IRE1、CCAAT/增强子结合蛋白同源蛋白(CHOP)、半胱氨酸天冬氨酸蛋白酶(Casepase)-3、Casepase-12、Ⅰ型胶原和Ⅲ型胶原的蛋白相对表达水平。结果病理组织学检查结果显示:对照组大鼠肺组织结构正常;矽肺模型组大鼠肺组织肺泡结构破坏严重,出现纤维细胞性结节及大量胶原沉积;PolyG预防组和PolyG治疗组大鼠矽结节及胶原沉积均较矽肺模型组减少。矽肺模型组大鼠肺组织中GRP78、IRE1、CHOP、Caspase-3、Caspase-12、Ⅰ型胶原和Ⅲ型胶原的蛋白相对表达水平均高于对照组(P<0.05)。除PolyG预防组IRE1和CHOP外,PolyG预防组和治疗组大鼠上述7个蛋白指标的表达水平均低于矽肺模型组(P<0.05),但仍高于对照组(P<0.05)。造模后第56天,PolyG预防组GRP78、IRE1、Caspase-3、Caspase-12、Ⅰ型胶原和Ⅲ型胶原的蛋白相对表达水平均低于PolyG治疗组(P<0.05)。结论 IRE1介导的ERS未折叠蛋白反应可能参与了PolyG干预大鼠矽肺纤维化的过程;PolyG可有效预防和治疗矽肺纤维化,以预防性给药效果更佳。Objective To investigate the role and mechanism of the endoplasmic reticulum stress （ERS） pathway of apoptosis mediated by inositol-requiring enzyme-1 （ IRE1 ） in the intervention of silicosis fibrosis in rats using polyguanylic acid （PolyG）. Methods The specific pathogen free adult male SD rats were randomly divided into control group （24 rats）, silicosis model group （24 rats）, PolyG intervention group （16 rats） and PolyG treatment group （16 rats）. The silicosis fibrosis rat model was constructed using the single inhalable intratracheal instillation method. The rats in the control group were injected with 1 mL of 0. 9% sodium chloride solution. The other 3 groups were given 1 mL of silica suspension at 50. 0 g/L mass concentration. The rats in PolyG intervention group on the day of model construction and rats in PolyG treatment group on the 28th day after model construction were all given PolyG with 2. 5 mg/kg body weight by one time tail vein intravenous injection. Eight rats in the PolyG intervention group and PolyG treatment group were sacrificed respectively on day 28 and day 56 after injection. The pathological changes of lung tissue in each group were observed. The expression of glucose regulated protein-78 （GRP78）, IRE1, CCAAT/enhancer-binding protein homologous protein （CHOP）, Casepase-3, Casepase-12, type I collagen and type III collagen in lung tissue was detected by the Western blot. Results The histopathology examination results showed that the structure of lung tissue in control group was normal. The alveolar structure of the lung tissue of the silicosis model group was severe, and the fibrous nodules and a large amount of collagen deposition appeared. The silicosis nodules and collagen deposition in PolyG intervention group and PolyG treatment group were less than those in silicosis model group. The expression of GRP78, IRE1, CHOP, Casepase-3, Casepase-12, type I collagen and type III collagen in silicosis model group was higher than that of control group （ P �

关 键 词：矽肺 肺纤维化 多聚鸟苷酸 内质网应激 肌醇需求激酶1 葡萄糖调节蛋白 CCAAT/增强子结合蛋白同源蛋白 半胱氨酸天冬氨酸蛋白酶 胶原 

分 类 号：R135.2[医药卫生—劳动卫生] R114[医药卫生—公共卫生与预防医学]