气相色谱-质谱联用技术分析大气细颗粒物对小鼠肺组织代谢轮廓的影响

摘要

建立了基于气相色谱-质谱联用技术(GC-MS)分析大气细颗粒物(PM2.5)滴注对小鼠肺组织代谢轮廓的影响的研究方法.通过分析肺组织细胞内代谢物的变化,研究不同浓度PM2.5对小鼠肺组织代谢的毒性机制.鼻腔分别滴注0、7.5、20.0和37.5 g/L的PM2.5悬液,提取肺组织胞内物质,预处理后进行GC-MS分析,结合主成分分析法(PCA)、偏最小二乘判别分析法(PLS-DA)进行数据解析,通过PLS-DA得分图可将不同PM2.5染毒浓度下的肺组织胞内物质明显区分.运用PLS-DA载荷图及模型的变量重要性因子(VIP)值,发现了7种代谢物可作为区别不同浓度PM2.5下代谢组的潜在生物标志物,分别为丙氨酸、缬氨酸、亮氨酸、鸟氨酸、延胡索酸、柠檬酸、嘌呤(p<0.01).代谢途径分析结果表明,PM2.5滴注使小鼠肺组织受到氧化损伤,氧化应激反应增强,抑制了三羧酸循环(TCA循环)及嘌呤代谢.本研究为深入解析PM2.5致毒机理提供了新的方法及理论依据.%A method based on gas chromatography-mass spectrometry (GC-MS) was established to analyze the changes of intracellular metabolites and study the toxic mechanisms of different concentrations of particulate matter (PM2.5) effecting the lung tissues in mice.Nasal drip experiments of PM2.5 suspensions (0, 7.5, 20.0, 37.5 g/L) for mice were carried out, and the intracellular metabolites in lung tissues were extracted, pretreated and analyzed.Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were employed for pattern recognition, and an obvious distinction among different conditions was found.According to the PLS-DA loading diagram and variable important factor (VIP) value, 7 kinds of potential biomarkers, alanine, valine, leucine, ornithine, fumaric acid, citric acid and purine (p<0.01), were determined with significant differences between four different concentrations of PM2.5.Metabolic pathway analysis indicated that the oxidative stress reactions were enhanced, and the TCA cycle and the purine metabolism in lung cells were restrained after dripping PM2.5 to the lung tissues in mice.This study could provide a new perspective and theoretical basis for the further analysis on toxic mechanisms by PM2.5.