title: Normal postprandial nonesterified fatty acid uptake in muscles despite increased circulating fatty acids in type 2 diabetes.
abstract: OBJECTIVE
  Postprandial plasma nonesterified fatty acid (NEFA) appearance is increased in type 2 diabetes. Our objective was to determine whether skeletal muscle uptake of plasma NEFA is abnormal during the postprandial state in type 2 diabetes.
  
  
  METHODS
  Thigh muscle blood flow and oxidative metabolism indexes and NEFA uptake were determined using positron emission tomography coupled with computed tomography (PET/CT) with [(11)C]acetate and 14(R,S)-[(18)F]fluoro-6-thia-heptadecanoic acid ((18)FTHA) in seven healthy control subjects (CON) and seven subjects with type 2 diabetes during continuous oral intake of a liquid meal to achieve steady postprandial NEFA levels with insulin infusion to maintain similar plasma glucose levels in both groups.
  
  
  RESULTS
  In the postprandial state, plasma NEFA level was higher in type 2 diabetic subjects versus CON (P < 0.01), whereas plasma glucose was at the same level in both groups. Muscle NEFA fractional extraction and blood flow index levels were 56% (P < 0.05) and 24% (P = 0.27) lower in type 2 diabetes, respectively. However, muscle NEFA uptake was similar to that of CON (quadriceps femoris [QF] 1.47 ± 0.23 vs. 1.37 ± 0.24 nmol·g(-1)·min(-1), P = 0.77; biceps femoris [BF] 1.54 ± 0.26 vs. 1.46 ± 0.28 nmol·g(-1)·min(-1), P = 0.85). Muscle oxidative metabolism was similar in both groups. Muscle NEFA fractional extraction and blood flow index were strongly and positively correlated (r = 0.79, P < 0.005).
  
  
  CONCLUSIONS
  Postprandial muscle NEFA uptake is normal despite elevated systemic NEFA levels and acute normalization of plasma glucose in type 2 diabetes. Lower postprandial muscle blood flow with resulting reduction in muscle NEFA fractional extraction may explain this phenomenon.
authors.affiliation: Centre de recherche clinique Etienne-Le Bel, Québec, Canada.
authors.forename: Sébastien M
authors.initials: SM
authors.lastname: Labbé
authors.forename: Etienne
authors.initials: E
authors.lastname: Croteau
authors.forename: Thomas
authors.initials: T
authors.lastname: Grenier-Larouche
authors.forename: Frédérique
authors.initials: F
authors.lastname: Frisch
authors.forename: René
authors.initials: R
authors.lastname: Ouellet
authors.forename: Réjean
authors.initials: R
authors.lastname: Langlois
authors.forename: Brigitte
authors.initials: B
authors.lastname: Guérin
authors.forename: Eric E
authors.initials: EE
authors.lastname: Turcotte
authors.forename: André C
authors.initials: AC
authors.lastname: Carpentier
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*; D019518:Postprandial Period / Q000502:physiology*; D013848:Thigh / Q000098:blood supply
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified