title: Increased serum levels of lipogenic enzymes in patients with severe liver steatosis.
abstract: BACKGROUND
  Lipid metabolism is altered in subjects with liver steatosis. FAS is a key enzyme in de novo lipogenesis and both FAS gene expression and enzymatic activity are primarily regulated by metabolic signals in the liver. Lipoprotein lipase (LPL), the rate-limiting enzyme for the hydrolysis of core triglycerides, plays a pivotal role in lipid metabolism. This study aims to investigate if circulating levels of FAS and LPL could be clinically associated with liver steatosis.
  
  
  METHODS
  In this work, we present data obtained from a subsample of 94 subjects with liver steatosis enrolled by NUTRIEPA study, a nutritional trial in subjects with liver steatosis. Serum levels of FAS protein and LPL activity were evaluated by ELISA test and by a fluorescent method, respectively. The diagnosis and the degree of liver steatosis were based on laboratory and ecographic measurements. Statistical methods included Kruskal-Wallis analysis of variance and Wilcoxon signed-rank test, where appropriate. The χ2 test has been performed to analyse categorical variables.
  
  
  RESULTS
  The subjects with severe steatosis had significantly higher serum levels of FAS protein and LPL activity compared to subjects with mild and moderate liver steatosis. Moreover, a positive trend in serum levels of FAS expression from lower to higher degree of steatosis was also detected.
  
  
  CONCLUSIONS
  We describe a relationship between human liver steatosis and elevated levels of circulating lipogenic enzymes. Increased serum levels of FAS expression and LPL activity could be considered a marker of severe liver steatosis.
authors.affiliation: Laboratory of Biochemistry, National Institute for Digestive Diseases, Castellana Grotte, 70013, Bari, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Notarnicola
authors.forename: Giovanni
authors.initials: G
authors.lastname: Misciagna
authors.forename: Valeria
authors.initials: V
authors.lastname: Tutino
authors.forename: Marisa
authors.initials: M
authors.lastname: Chiloiro
authors.forename: Alberto Ruben
authors.initials: AR
authors.lastname: Osella
authors.forename: Vito
authors.initials: V
authors.lastname: Guerra
authors.forename: Caterina
authors.initials: C
authors.lastname: Bonfiglio
authors.forename: Maria Gabriella
authors.initials: MG
authors.lastname: Caruso
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D054890:Fatty Acid Synthase, Type I / Q000097:blood*; D005234:Fatty Liver / Q000097:blood* / Q000201:enzymology*; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008071:Lipoprotein Lipase / Q000097:blood*; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers; C518729:FASN protein, human; D054890:Fatty Acid Synthase, Type I; C548261:LPL protein, human; D008071:Lipoprotein Lipase