Serum metabonomics of NAFLD plus T2DM based on liquid chromatography-mass spectrometry

Objectives: Nonalcoholic fatty liver disease (NAFLD), a main liver disease around the world, is closely associated with insulin resistance, type 2 diabetes mellitus (T2DM) and other metabolic diseases. The objective of this study is to identify distinct metabolites of NAFLD patients with or without T2DM. Design and methods: We used a biomarker-discovery population to find distinct metabolites of NAFLD patients with or without T2DM. Then, a validation population was applied to test the model of the biomarker-discovery population. All the individuals received anthropometric and common biochemical measurements. The metabolic data were analyzed by multivariable statistical analyses using ultra-high-performance liquid chromatography/quadrupole time-of-flight-tandem mass spectrometry. Results: There were 7,7,2 metabolites in the positive electrospray ionization (ESI) mode, which were identified between groups from both the biomarker-discovery and validation population. The NAFLD group showed higher concentrations of oleamide, L-phenylalanine, L-proline, bilirubin, L-palmitoylcarnitine, and PC (20:5) and a lower concentration of Lyso-PAF C-18 than those of control. Compared with the control group, the NAFLD + T2DM group displayed higher oleamide, L-leucine, LysoPC (14:0), bilirubin, tetradecenoylcarnitine, linoleyl carnitine, and tetradecadiencarnitine in serum. Tetradecenoylcarnitine and tetradecadiencarnitine were more elevated in patients with NAFLD + T2DM than in the NAFLD group. Conclusions: Serum metabonomic analyses displayed great metabolic changes in patients with NAFLD and NAFLD plus T2DM. Our study is beneficial in providing a further view into the pathogenesis and pathophysiology of NAFLD and NAFLD plus T2DM, which might be useful for the prevention and therapy of NAFLD and NAFLD plus T2DM. (C) 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.