鞣花酸对D-型半乳糖致衰老大鼠干预的尿液代谢组学生物标志物的筛选及代谢通路分析

目的：利用高效液相色谱串联质谱仪（LC-MS）的尿液代谢组学方法，考察鞣花酸对D-型半乳糖致衰老大鼠内源性物质代谢的影响，寻找潜在的生物标志物并分析代谢途径，为研究鞣花酸对D-型半乳糖致衰老大鼠的改善作用及其机制提供理论依据。方法：采用皮下颈静脉注射D-型半乳糖的方法建立氧化衰老大鼠模型，灌胃给予鞣花酸连续8周，收集给药8周24 h尿液，用液相色谱--高分辨质谱对其检测分析；采用主成份分析（PCA）、偏最小二乘法判别分析（PLS-DA）及正交偏最小二乘法判别分析（OPLS-DA）等方法对正常对照组，模型组，阳性对照组，鞣花酸高剂量组、中剂量组、低剂量组6组大鼠尿液代谢物进行聚类分析，筛选出潜在的生物标志物并构建相应的代谢通路。结果：代谢组学分析发现造模后第8周各组大鼠尿液有明显的聚类现象，通过对重要变量的分析鉴定，筛选出12个潜在的生物标志物；涉及的代谢通路包括三羧酸循环、色氨酸代谢、丙酮酸代谢、二元羧酸及牛磺酸代谢等。结论：鞣花酸干预下的D-型半乳糖致衰老大鼠内源性代谢物聚类性趋近正常水平，为进一步阐明鞣花酸对D-型半乳糖致衰老大鼠的作用机制提供依据。

Screening and metalizing pathway of biomarkers of urinary metabonomics in D-galactose induced aging rats intervened by ellagic acid

OBJECTIVE To utilize a urinary metabonomics method based on liquid chromatography-mass spectrometry (LC-MS) to investigate the effect of ellagic acid on D-galactose-induced aging rats,search potential biomarkers and analyze the metabolic pathways to provide relevant theory for improvement of D-galactose induced aging rats.METHODS D-galactose induced aging model was established by the method of hypodermic intrajugular injection of D-galactose.The 24 h urine of rats was collected after the rats were orally given ellagic acid for eight weeks.Liquid chromatography-mass spectrometry was used for testing and analyzing the urine.Principal component analysis (PCA),partial least squares-discriminant analysis (PLS-DA) and the orthogonal partial least squares discriminant analysis were used for data treatment of model group,normal group,control group,dose group to search the potential biomarkers and build the metabolicomics pathways.RESULTS It showed that the urinary metabolism of rats was clustering.Totally 12 potential biomakers were screened by analysis and identification of important variables.The metabonomics pathways involved tricarboxylic acid circulation (TCA),tryptophan metabolism,pyruvate metabolism,dicarboxylic acid and taurine metabolism,etc.CONCLUSION The endogenous metabolism of D-galactose induced aging rats tends to be normal after intervened by ellagic acid.It provides the basement for the further research of clarifying the mechanism of ellagic acid affecting D-galactose induced aging rats.