姚琳+张俊威+孟庆杰+董坤+王伟明

摘要：目的 观察PM2.5致大鼠肺损伤及桔梗总皂苷（PGS）对其的干预作用，探讨PGS对PM2.5致肺损伤修复的机制。方法 采用气管滴注法染毒制作PM2.5致大鼠肺损伤模型。实验大鼠随机分为空白组、模型组和PGS高、中、低剂量组，每组10只。给药14 d后，收集肺泡灌洗液（BALF），采集大鼠左肺及右肺组织中叶，HE染色观察肺组织病理改变，ELISA检测BALF肿瘤坏死因子-α（TNF-α）、白细胞介素（IL）-6、IL-10、IL-13的含量；RT-PCR检测肺组织转化生长因子-β（TGF-β）mRNA的表达，免疫印迹法检测肺组织TGF-β的蛋白表达。结果 与模型组比较，PGS高、中剂量组BALF TNF-α、IL-6显著降低，IL-10、IL-13显著升高，PGS各剂量组大鼠肺组织炎细胞浸润减少，肺间质水肿和纤维增生减轻，肺组织TGF-β mRNA和蛋白表达降低。结论 PGS可能通过调节炎性细胞因子的平衡减轻PM2.5引起的肺组织炎症，并通过下调TGF-β的表达抑制肺纤维化进程，从而对PM2.5致大鼠肺损伤具有一定的保护及修复作用。

关键词：桔梗总皂苷；PM2.5；炎性细胞因子；转化生长因子-β；大鼠

DOI：10.3969/j.issn.1005-5304.2017.12.010

中图分类号：R285.5 文献标识码：A 文章编号：1005-5304（2017）12-0038-04

Study on Lung Injury of Rats Caused by PM2.5 and Intervention Effect of Platycodonis Radix Total Saponins YAO Lin， ZHANG Jun-wei， MENG Qing-jie， DONG Kun， WANG Wei-ming （Heilongjiang Academy of Chinese Medical Sciences， Harbin 150036， China）

Abstract： Objective To observe the lung injury of rats caused by PM2.5 and the intervention effect of Platycodonis Radix total saponins （PGS）； To discuss the repair mechanism of PGS for lung injury caused by PM2.5. Methods The model of lung injury caused by PM2.5 was induced by tracheal instillation. The rats were randomly divided into blank group， model group and PGS high-， medium- and low-dose groups， with 10 rats in each group. After medication for 14 d， BALF and left lung and right lung tissue of rats were collected. HE staining was used to observe the pathological changes of lung tissue. The contents of TNF-α， IL-6， IL-10 and IL-13 in BALF were detected by ELISA. RT-PCR was used to detect the expression of TGF-β mRNA in lung tissues. The expression of TGF-β protein in lung tissue was detected by Western blot. Results Compared with model group， TNF-α and IL-6 decreased significantly while IL-10 and IL-13 increased significantly in BALF in high- and medium-dose group of PGS. Degree of pulmonary interstitial edema and fibroplasia alleviated in PGS groups. Expressions of TGF-β mRNA and protein in lung tissue was reduced in PGS groups. Conclusion PGS can alleviate inflammatory injury caused by PM2.5 via regulating the balance of cytokine and down-regulating the expression of TGF-β and inhibiting the development of fibrosis， which results in the protection and repair on the lung injury of rats caused by PM2.5.

Key words： Platycodonis Radix total saponins； PM 2.5； inflammatory cytokines； TGF-β； rats

PM2.5是大氣污染的主要成分，是影响身体健康的主要因素之一，近年来已成为研究的热点。越来越多的流行病学和毒理学资料表明，PM2.5与呼吸道疾病和慢性心肺疾病的发病率密切相关[1-3]。由于PM2.5endprint

基金项目：黑龙江省青年科学基金（QC2014C115）

通讯作者：王伟明，E-mail：342201601@qq.com

粒径小，可随气流进入呼吸道深部，沉积在终末细支气管和肺泡，通过刺激和作用肺泡巨噬细胞、肺泡Ⅱ型上皮细胞，造成肺部炎性损伤及纤维化[4]。肿瘤坏死因子-α（TNF-α）、白细胞介素（IL）-6是机体内产生的重要促炎细胞因子，肺细胞在外源性物质刺激下，可以释放上述炎性因子，介导炎症反应。……