title: Characteristics of hepatic fatty acid compositions in patients with nonalcoholic steatohepatitis.
abstract: OBJECTIVE
  Nonalcoholic fatty liver disease (NAFLD) is closely related to insulin resistance and lipid metabolism. Recent studies have suggested that the quality of fat accumulated in the liver is associated with the development of nonalcoholic steatohepatitis (NASH). In this study, we investigated the fatty acid composition in liver tissue and its association with the pathology in NAFLD patients.
  
  
  METHODS
  One hundred and three patients diagnosed with NAFLD [simple steatosis (SS): 63, NASH: 40] were examined and their hepatic fatty acids were measured using gas chromatography. In addition, relationships between the composition and composition ratios of various fatty acids and patient backgrounds, laboratory test values, histology of the liver, and expression of fat metabolism-related enzymes were investigated.
  
  
  RESULTS
  The C16:1n7 content, the C16:1n7/C16:0 and C18:1n9/C18:0 ratios were increased and the C18:0/C16:0 ratio was decreased in the NASH group. The C18:0/C16:0 and C18:1n9/C18:0 ratios were associated with the steatosis score in liver tissue, and the C16:1n7/C16:0 ratio was associated with the lobular inflammation score. The expressions levels of genes: SCD1, ELOVL6, SREBP1c, FAS and PPARγ were enhanced in the NASH group. In multivariate analysis, the C18:0/C16:0 ratio was the most important factor that was correlated with the steatosis score. In contrast, the C16:1n7/C16:0 ratio was correlated with lobular inflammation.
  
  
  CONCLUSIONS
  The fatty acid composition in liver tissue and expression of genes related to fatty acid metabolism were different between the SS and NASH groups, suggesting that the acceleration of fatty acid metabolism is deeply involved in pathogenesis of NASH.
authors.affiliation: Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Yamada
authors.forename: Eishiro
authors.initials: E
authors.lastname: Mizukoshi
authors.forename: Hajime
authors.initials: H
authors.lastname: Sunagozaka
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Arai
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Yamashita
authors.forename: Yumie
authors.initials: Y
authors.lastname: Takeshita
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Misu
authors.forename: Toshinari
authors.initials: T
authors.lastname: Takamura
authors.forename: Seiko
authors.initials: S
authors.lastname: Kitamura
authors.forename: Yoh
authors.initials: Y
authors.lastname: Zen
authors.forename: Yasuni
authors.initials: Y
authors.lastname: Nakanuma
authors.forename: Masao
authors.initials: M
authors.lastname: Honda
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kaneko
mesh_terms: D000123:Acetyltransferases / Q000378:metabolism; D002849:Chromatography, Gas; D000081031:Fatty Acid Elongases; D050556:Fatty Acid-Binding Proteins / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D020869:Gene Expression Profiling; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D008099:Liver / Q000378:metabolism*; D015999:Multivariate Analysis; D065626:Non-alcoholic Fatty Liver Disease / Q000378:metabolism* / Q000473:pathology; D047495:PPAR gamma / Q000378:metabolism; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism; D051780:Sterol Regulatory Element Binding Protein 1 / Q000378:metabolism; D019014:fas Receptor / Q000378:metabolism
chemical_list: C000630955:ELOVL6 protein, human; C491901:FAS protein, human; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D047495:PPAR gamma; C497387:SREBF1 protein, human; D051780:Sterol Regulatory Element Binding Protein 1; D019014:fas Receptor; C523776:SCD1 protein, human; D013230:Stearoyl-CoA Desaturase; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases
keywords: fatty acid metabolism; insulin resistance; palmitic acid; toxic lipid