title: Influence of elevated liver fat on circulating adipocytokines and insulin resistance in obese Hispanic adolescents.
abstract: OBJECTIVE
  We performed this study to examine the metabolic differences arising from higher liver fat accumulation in obese Hispanic adolescents, with a particular focus on circulating levels of adipocytokines and insulin resistance.
  
  
  METHODS
  Forty-one obese Hispanic adolescents (15.3 ± 1.0 years, body mass index percentile: 97.0 ± 3.9) were assessed for: visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and hepatic fat fraction (HFF) by magnetic resonance imaging; fasting measures of serum glucose, insulin and adipocytokines; homeostasis model assessment of insulin resistance (HOMA-IR); and insulin sensitivity (SI) and the acute insulin response to glucose (AIR) by intravenous glucose tolerance test. Subjects with normal levels of HFF (below 5%; n = 25) were compared to those with HFF > 5% (n = 16).
  
  
  RESULTS
  The two groups differing in HFF were similar for total body fat, VAT and SAT. The group with HFF > 5% had significantly (P < 0.05) higher interleukin-8 (IL-8) (6.1 ± 1.6 vs. 3.2 ± 0.4 pg mL(-1) ), NGF (30.2 ± 9.9 vs. 13.9 ± 1.6 pg mL(-1) ), HOMA-IR (8.8 ± 1.1 vs. 5.5 ± 0.5), AIR (1869 ± 206 vs. 1092 ± 165) and a tendency for lower SI (1.2 ± 0.4 vs. 2.1 ± 0.3; P = 0.06), with no significant differences in any of other factors measured.
  
  
  CONCLUSIONS
  These data suggest that elevated liver fat is most closely associated with elevated serum IL-8 and NGF levels as well as increased AIR and HOMA-IR. These elevated factors may play significant roles in the metabolic abnormalities associated with elevated liver fat in obese Hispanics.
authors.affiliation: Department of Preventive Medicine, Childhood Obesity Research Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Kim
authors.forename: K-A
authors.initials: KA
authors.lastname: Lê
authors.forename: S
authors.initials: S
authors.lastname: Mahurkar
authors.forename: J N
authors.initials: JN
authors.lastname: Davis
authors.forename: M I
authors.initials: MI
authors.lastname: Goran
mesh_terms: D054392:Adipokines / Q000097:blood*; D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D002140:California; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000517:prevention & control / Q000628:therapy; D005234:Fatty Liver / Q000378:metabolism / Q000517:prevention & control / Q000628:therapy; D005260:Female; D005951:Glucose Tolerance Test; D006630:Hispanic or Latino / Q000193:education*; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000517:prevention & control / Q000628:therapy; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D020932:Nerve Growth Factor / Q000097:blood; D065626:Non-alcoholic Fatty Liver Disease; D009765:Obesity / Q000378:metabolism / Q000517:prevention & control / Q000628:therapy; D010353:Patient Education as Topic / Q000379:methods*
chemical_list: D054392:Adipokines; D001786:Blood Glucose; C508606:CXCL8 protein, human; D007328:Insulin; D016209:Interleukin-8; D020932:Nerve Growth Factor