title: Liver tissue metabolic profiling and pathways of non-alcoholic steatohepatitis in rats.
abstract: OBJECTIVE
  The mechanisms of non-alcoholic steatohepatitis (NASH) in hepatocytes are unknown. Our aim is to study the tissue metabolic profiling and pathways of NASH.
  
  
  METHODS
  We built rat models for simple steatosis and NASH and analyzed the liver extract using a liquid chromatograph-mass spectrometer. The acquired data were processed by multivariate principal component analysis and partial least squares discriminant analysis (PLS-DA) to obtain metabolic profiling. Orthogonal projections to latent structures DA was used to obtain metabolites capable of distinguishing NASH and steatosis. The total differences in the metabolites between groups were analyzed to determine their metabolic pathways.
  
  
  RESULTS
  Principal component analysis showed that the metabolic profiles of NASH and steatosis are different. The PLS-DA modeling revealed a clear separation between two groups with parameters R2Y and Q2Y all greater than 0.7. The orthogonal projections to latent structures DA model identified 171 metabolites capable of distinguishing NASH from steatosis. The identified metabolites are involved in fatty acid metabolism, tryptophan metabolism, the urea cycle, and the citric acid cycle in hepatocytes.
  
  
  CONCLUSIONS
  These metabolic profiles and pathways in rat hepatocytes will offer useful information when studying metabolic disorders in patients with NASH.
authors.affiliation: National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, China.
authors.forename: Suwen
authors.initials: S
authors.lastname: Qi
authors.affiliation: National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, China.
authors.forename: Si
authors.initials: S
authors.lastname: Huang
authors.affiliation: National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Huo
authors.affiliation: Core Laboratory, Shenzhen Second Hospital (The First Affiliated Hospital of Shenzhen University), Shenzhen, China.
authors.forename: Ni
authors.initials: N
authors.lastname: Xie
authors.affiliation: Core Laboratory, Shenzhen Second Hospital (The First Affiliated Hospital of Shenzhen University), Shenzhen, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xia
keywords: metabolic pathways; metabolic profiling; non-alcoholic steatohepatitis; steatosis