title: Adipocyte cell size, free fatty acids and apolipoproteins are associated with non-alcoholic liver injury progression in severely obese patients.
abstract: OBJECTIVE
  Obesity is a modern pandemic with continuous expansion and represents an independent risk factor for non-alcoholic fatty liver disease (NAFLD), the most common liver disease in westernized countries. The crosstalk between adipose tissue and the liver is key to the development of NAFLD.
  
  
  METHODS
  Therefore, in an observational study blood, visceral adipose tissue and liver tissue were obtained from 93 severely obese patients with a mean age of 43 years and mean BMI of 52 kg/m2 at the time of weight loss surgery. In a subset of patients a follow-up blood sample was obtained 6 weeks after surgery to assess acute effects of weight loss. In addition to routine parameters of liver injury, serum samples were analyzed for leptin, adiponectin, free fatty acids (FFAs), and several apolipoproteins.
  
  
  RESULTS
  The diameter of visceral adipocytes correlated to liver injury, serum markers of inflammation and serum adipokine levels. Liver injury assessed by serology (ALT, AST) and histology (NAFLD activity score, NAS) was independent of the BMI. However, serum levels of triglycerides and Apolipoprotein CIII (ApoCIII) were associated with NAS. Serum levels and composition of FFAs, especially long chain FFAs, also correlated with NAS. Analysis of serum samples six weeks after surgery revealed beneficial changes in serum triglycerides, levels of ApoCIII and several FFAs.
  
  
  CONCLUSIONS
  In severely obese patients beneficial effects on liver injury can been observed as early as six weeks after bariatric surgery. These effects may be explained by the observed changes in adipose tissue and lipid metabolism. Collectively, these findings underline the importance of the link between adipose tissue and the liver.
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany; Department of Pediatrics, University of California San Diego (UCSD), CA, 92037, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Wree
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schlattjan
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany.
authors.forename: Lars P
authors.initials: LP
authors.lastname: Bechmann
authors.affiliation: Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090, Austria.
authors.forename: Thierry
authors.initials: T
authors.lastname: Claudel
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany.
authors.forename: Jan-Peter
authors.initials: JP
authors.lastname: Sowa
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Austria.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Stojakovic
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Austria.
authors.forename: Hubert
authors.initials: H
authors.lastname: Scharnagl
authors.affiliation: Core Facility for Mass Spectrometry, Medical University of Graz, Graz, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Köfeler
authors.affiliation: Department of Pathology and Neuropathology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany.
authors.forename: Hideo A
authors.initials: HA
authors.lastname: Baba
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany.
authors.forename: Guido
authors.initials: G
authors.lastname: Gerken
authors.affiliation: Department of Pediatrics, University of California San Diego (UCSD), CA, 92037, USA.
authors.forename: Ariel E
authors.initials: AE
authors.lastname: Feldstein
authors.affiliation: Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090, Austria. Electronic address: michael.trauner@meduniwien.ac.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Trauner
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital, University Duisburg-Essen, Essen, 45122, Germany. Electronic address: ali.canbay@uni-due.de.
authors.forename: Ali
authors.initials: A
authors.lastname: Canbay
mesh_terms: D017667:Adipocytes / Q000502:physiology*; D052242:Adiponectin / Q000378:metabolism; D000328:Adult; D001053:Apolipoproteins / Q000097:blood*; D050110:Bariatric Surgery; D002097:C-Reactive Protein / Q000378:metabolism; D048429:Cell Size; D015331:Cohort Studies; D018450:Disease Progression; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D006801:Humans; D020738:Leptin / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000201:enzymology / Q000473:pathology*; D009765:Obesity / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D012720:Severity of Illness Index
chemical_list: D052242:Adiponectin; D001053:Apolipoproteins; D005230:Fatty Acids, Nonesterified; D020738:Leptin; D002097:C-Reactive Protein
keywords: Adipose tissue; Bariatric surgery; Hepatology; Non-alcoholic fatty liver disease; Obesity