轻微肝性脑病患者血清中代谢物组的研究

Study on metabolic signature of serum in patients with mild hepatic encephalopathy

目的检测轻微肝性脑病(minimal hepatic encephalopathy,MHE)患者血清中的代谢物组,初步建立MHE诊断模型。方法采用核磁共振(NMR)方法检测25例肝硬化患者(肝硬化组)、25例轻微肝性脑病患者(MHE组)和30例健康对照(对照组)血清中的代谢物,应用主成分分析(PCA)和正交偏最小二乘法-判别分析(OPLS-DA)对NMR谱数据进行模式识别分析,并用临床标本验证代谢组模型诊断MHE的可行性。结果 OPLS-DA模型显示,健康对照与肝硬化患者(包括肝硬化组和MHE组患者)之间的区分非常明显,模型的质量参数R2X=35.1%,Q2Y=0.902;肝硬化组和MHE组标本可区分开来,模型质量参数R2 X=30.4%,Q2 Y=0.817。与对照组相比,肝硬化组和MHE组患者血清中葡萄糖、琥珀酸盐、柠檬酸盐等含量增高,低密度脂蛋白、极低密度脂蛋白、胆碱等含量减少;与肝硬化组相比,MHE组患者血清中的谷氨酰胺、苯丙氨酸、丙酮增高,缬氨酸和异亮氨酸降低。模型准确预测了10例MHE血清标本中的8例。结论基于1H NMR代谢组学技术可同时检测患者血清中多种代谢物质,有助于研究肝硬化和MHE的发病机制,可能为MHE的诊断提供一种新的手段。

Objective To investigate the metabonomics of serum samples from patients with mild hepatic encephalopathy（MHE） and to establish a diagnostic model for MHE.Methods Nuclear magnetic resonance spectroscopy（NMR） was applied to analyze serum metabonomics from 25 patients with simple liver cirrhosis（cirrhosis group）,25 cirrhotic patients with mild hepatic encephalopathy（MHE group） and 30 healthy volunteers（control group）.Principal component analysis（PCA） and orthogonal partial least-squares-discriminant analysis（OPLS-DA） were employed to establish a pattern recognition analysis of NMR spectra.Clinical samples were used to evaluate the performance of the diagnostic model for MHE.Results The OPLS-DA model could distinguish the cirrhotic patients from the healthy controls with R2X=35.1% and Q2Y =0.902,and could also distinguish the patients with and without MHE with R2X =30.4% and Q2Y =0.817.In comparison with the healthy volunteers,the patients with liver cirrhosis and with MHE were characterized by increased serum levels of glucose,succinate,citrate and decreased levels of low-density lipoprotein（LDL）,very low-density lipoprotein（VLDL） and choline.Compared with the cirrhotic patients without MHE,the MHE patients showed increased serum levels of glutamine,phenylalanine and acetone and decreased serum levels of valine and isoleucine.The accuracy ratio of OPLS-DA model for MHE was 80%（8/10）.Conclusion Metabonomics spectra based on 1H NMR combined with pattern recognition analysis can detect various metabolites in serum of cirrhotic patients with and without MHE at the same time,which offers a new way for studying the pathogenesis of liver cirrhosis and MHE,and for the diagnosis of MHE in the future.