title: Enhanced fatty acid uptake in visceral adipose tissue is not reversed by weight loss in obese individuals with the metabolic syndrome.
abstract: OBJECTIVE
  Obesity causes an imbalance in fat mass distribution between visceral and subcutaneous adipose tissue (AT) depots. We tested the hypothesis that this relates to increased NEFA uptake between these depots in obese compared with healthy participants. Second, we hypothesised that a diet very low in energy (very low calorie diet [VLCD]) decreases fat mass in obese participants and that this is associated with the decline in NEFA uptake.
  
  
  METHODS
  NEFA uptake in AT depots was measured with [(18)F]-fluoro-6-thia-heptadecanoic acid ((18)F-FTHA) and positron emission tomography (PET) in 18 obese participants with the metabolic syndrome before and after a 6 week VLCD. Whole body fat oxidation was measured using indirect calorimetry and [U-(13)C]palmitate. Sixteen non-obese participants were controls.
  
  
  RESULTS
  Obese participants had >100% higher (p < 0.0001) NEFA uptake in the visceral and subcutaneous abdominal AT depots than controls. VLCD decreased AT mass in all regions (12% to 21%), but NEFA uptake was decreased significantly (18%; p < 0.006) only in the femoral AT. Whole body carbohydrate oxidation decreased, while fat oxidation increased.
  
  
  CONCLUSIONS
  The data demonstrate that weight loss caused by VLCD does not affect abdominal fasting NEFA uptake rates. We found that visceral fat takes up more NEFAs than subcutaneous AT depots, even after weight loss.
authors.affiliation: Turku PET Centre, University of Turku and Turku University Hospital, P.O. Box 52, FI-20521, Turku, Finland, marbuc@utu.fi.
authors.forename: Marco
authors.initials: M
authors.lastname: Bucci
authors.forename: Anna C
authors.initials: AC
authors.lastname: Karmi
authors.forename: Patricia
authors.initials: P
authors.lastname: Iozzo
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Fielding
authors.forename: Antti
authors.initials: A
authors.lastname: Viljanen
authors.forename: Robert M
authors.initials: RM
authors.lastname: Badeau
authors.forename: Ronald
authors.initials: R
authors.lastname: Borra
authors.forename: Virva
authors.initials: V
authors.lastname: Saunavaara
authors.forename: Tam
authors.initials: T
authors.lastname: Pham
authors.forename: Jarna C
authors.initials: JC
authors.lastname: Hannukainen
authors.forename: Kari
authors.initials: K
authors.lastname: Kalliokoski
authors.forename: Merja
authors.initials: M
authors.lastname: Haaparanta-Solin
authors.forename: Tapio
authors.initials: T
authors.lastname: Viljanen
authors.forename: Riitta
authors.initials: R
authors.lastname: Parkkola
authors.forename: Keith N
authors.initials: KN
authors.lastname: Frayn
authors.forename: Pirjo
authors.initials: P
authors.lastname: Nuutila
mesh_terms: D000328:Adult; D031204:Caloric Restriction; D002153:Calorimetry, Indirect; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005260:Female; D006801:Humans; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000378:metabolism*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000378:metabolism; D009765:Obesity / Q000150:complications / Q000178:diet therapy / Q000378:metabolism*; D049268:Positron-Emission Tomography; D011859:Radiography; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging / Q000378:metabolism; D015431:Weight Loss / Q000502:physiology*
chemical_list: D005230:Fatty Acids, Nonesterified