气相色谱-质谱法结合偏最小二乘-判别分析用于血清和血浆中代谢物的比较分析

Gas Chromatography-Mass Spectrometry and PLS-DA Applied for Comparative Analysis of Serum and Plasma

建立了肟化-硅烷化衍生血清和血浆中代谢物的方法,结合气相色谱-质谱法,可实现有机酸、氨基酸、脂肪酸和胆固醇等多类代谢物的同时分析测定。方法学考察结果表明,该方法准确可靠,重复性、精密度和回收率良好,满足血清和血浆样本代谢物分析的要求。利用建立的方法,对40个健康人血清样本和34个健康人血浆样本中的代谢物进行对比分析。结果表明,吲哚-3-乙酸是血浆中特有的代谢物;共有的39个代谢物中,有32种在血清和血浆中的含量有显著性差异。采用偏最小二乘-判别分析(PLSDA)建立血清和血浆的判别模型,并筛选出了5种区分血清和血浆的重要代谢物,即磷酸、异亮氨酸、2,3,4-三羟基丁酸、柠檬酸和硬脂酸。研究结果为代谢组学研究中血清和血浆样本的选择提供了依据。

A combination of methoximation followed by trimethylsilyl（TMS）derivatization（MeOx-TMS method）was developed for simultaneous determination of various endogenous metabolites,including organic acids,amino acids,fatty acids and cholesterol,in serum and plasma.Results of methodological study indicated that the method was accurate and reliable with good repeatability,precision and recovery,which can satisfy the requirements of metabolites analysis in serum and plasma.In this study,40 sera samples and 34 plasma samples of healthy controls were collected.Indole-3-acetic acid was found to be the specific metabolite in blood plasma.In addition,significant differences existed between the concentration of most commom metabolites in serum and plasma.The discriminant model between serum and plasma was built up using partial least squares-discriminant analysis（PLS-DA）.Five characteristic metabolites which have great contribution to the discrimination were screened,including phosphate,isoleucine,2,3,4-trihydroxybutyrate,citric acid and stearic acid.