title: Potential role of interleukin-18 in liver disease associated with insulin resistance.
abstract: OBJECTIVE
  Interleukin (IL)-18 has been associated with obesity and insulin resistance, both risk factors for the development of liver disease, but the role of IL-18 in liver disease associated with insulin resistance is presently unknown. We hypothesized that circulating IL-18 would be related to serum concentrations of liver chemistry tests (LCTs) in apparently healthy subjects and wished to study whether this correlation was dependent on insulin sensitivity (S(I)).
  
  
  METHODS
  One hundred six apparently healthy white men consecutively enrolled in a cross-sectional, population-based study dealing with S(I) in men were studied, and S(I) (minimal model analysis), LCTs (colorimetry), and IL-18 serum concentrations (immunoassay) were assessed.
  
  
  RESULTS
  Compared with subjects in the lowest quartile for serum IL-18, subjects in the highest quartile exhibited increased serum triglycerides and decreased S(I), in addition to higher serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) (all p < 0.05). The direct association between both ALT and AST and IL-18 was further confirmed by examining the distribution of serum IL-18 by quartiles of ALT and AST. Subjects in the highest quartile for serum ALT and AST had higher IL-18 concentrations compared with subjects in the lowest quartile for these LCTs (both p = 0.01). In multiple regression analysis, IL-18, but not S(I), was an independent predictor of serum concentrations of ALT and AST, explaining 7% and 4% of their variance, respectively.
  
  
  CONCLUSIONS
  In summary, IL-18 serum concentrations are associated in apparently healthy humans with plasma concentrations of various LCTs. IL-18 could contribute to the development of liver disease associated with insulin resistance.
authors.affiliation: Unit of Diabetes, Endocrinology, and Nutrition, Dr. Josep Trueta Hospital, Av. Francia s/n, 17007 Girona, Spain. uden.alopez@htrueta.scs.es
authors.forename: Abel
authors.initials: A
authors.lastname: López-Bermejo
authors.forename: Montserrat
authors.initials: M
authors.lastname: Bosch
authors.forename: Mònica
authors.initials: M
authors.lastname: Recasens
authors.forename: Josefina
authors.initials: J
authors.lastname: Biarnés
authors.forename: Eduardo
authors.initials: E
authors.lastname: Esteve
authors.forename: Roser
authors.initials: R
authors.lastname: Casamitjana
authors.forename: Joan
authors.initials: J
authors.lastname: Vendrell
authors.forename: Wifredo
authors.initials: W
authors.lastname: Ricart
authors.forename: José-Manuel
authors.initials: JM
authors.lastname: Fernández-Real
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000032:analysis / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D002784:Cholesterol / Q000097:blood; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D020382:Interleukin-18 / Q000097:blood*; D008099:Liver / Q000201:enzymology; D008107:Liver Diseases / Q000097:blood / Q000209:etiology / Q000503:physiopathology*; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D014280:Triglycerides / Q000097:blood
chemical_list: D001786:Blood Glucose; D007328:Insulin; D020382:Interleukin-18; D014280:Triglycerides; D002784:Cholesterol; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase