糖尿病合并非酒精性脂肪性肝病患者尿代谢组学研究

目的：运用气相色谱-质谱联用技术（GC/MS）技术观察糖尿病合并非酒精性脂肪性肝病（NAFLD）患者尿液中小分子代谢物，发现用于糖尿病合并NAFLD诊断的潜在生物标志物，为糖尿病合并NAFLD的发生机制和早期诊断提供代谢水平上的依据。方法：采用GC/MS检测20例正常人（正常组）、20例单纯糖尿病患者（单纯组）以及30例糖尿病合并NAFLD （合并组）的尿液样本中小分子代谢物。采用主成分分析法（PCA）和偏最小二乘法判别分析（PLS-DA）分析正常组、单纯组以及合并组的代谢谱变化。结果：正常组和单纯组的代谢谱完全分离，正常组和合并组的代谢谱分离良好。利用Wiley和NIST等数据库筛选和鉴定了19个与糖尿病合并NAFLD密切相关的潜在生物标志物。经过代谢通路分析，糖尿病合并NAFLD患者体内存在苯丙氨酸、酪氨酸和色氨酸的生物合成、苯丙氨酸代谢、组氨酸代谢、甘氨酸、丝氨酸和苏氨酸代谢、氨酰tRNA生物合成、色氨酸代谢、酪氨酸代谢等代谢异常。结论：糖尿病合并NAFLD的发生与苯丙氨酸、酪氨酸和色氨酸的生物合成、苯丙氨酸代谢、组氨酸代谢、甘氨酸、丝氨酸和苏氨酸代谢、氨酰tRNA生物合成、色氨酸代谢、酪氨酸代谢等代谢异常有关，尿液中鉴定的代谢物有望成为糖尿病合并NAFLD诊断的潜在生物标志物。

Urine metabolomics in diabetics with nonalcoholic fatty liver

OBJECTIVE To detect the small molecular metabolites in urine of patients with diabetes mellitus(DM) complicated with nonalcoholic fatty liver disease(NAFLD) by gas chromatography-mass spectrometry(GC/MS) and seek potential diagnostic biomarkers to provide metabolic rationales for the pathogenesis and early diagnosis of DM complicated with NAFLD.METHODS The urine samples of 20 normal subjects(normal group), 20 patients with simple DM(simple group) and 30 DM patients complicated with NAFLD(combined group) were detected by GC/MS. Principal component analysis(PCA) and partial least squares discriminant analysis(PLS-DA) were employed for examining the metabolic spectrum changes of normal, simple and combined groups.RESULTS The metabolic spectrum of normal and simple groups was completely separated and the metabolic spectrum of normal and combined groups well-separated. Nineteen potential biomarkers closely correlated with DM with NAFLD were screened and identified by the Wiley and NIST databases. According to the analysis of metabolic pathway, there were abnormal metabolism of phenylalanine/tyrosine/tryptophan biosynthesis, phenylalanine/histidine/glycine/serine/threonine metabolism, aminoacyl tRNA biosynthesis and tryptophan/tyrosine metabolism in DM with NAFLD.CONCLUSION DM with NAFLD is associated with such metabolic abnormalities as phenylalanine/tyrosine/tryptophan biosynthesis, phenylalanine/histidine/glycine/serine/threonine metabolism, aminoacyl tRNA biosynthesis and tryptophan/tyrosine metabolism. Metabolites identified in urine are expected to be potential diagnostic biomarkers for the DM with NAFLD.