title: Prandial hypertriglyceridemia in metabolic syndrome is due to an overproduction of both chylomicron and VLDL triacylglycerol.
abstract: The aim was to determine whether fed VLDL and chylomicron (CM) triacylglycerol (TAG) production rates are elevated in metabolic syndrome (MetS). Eight men with MetS (BMI 29.7 ± 1.1) and eight lean age-matched healthy men (BMI 23.1 ± 0.4) were studied using a frequent feeding protocol. After 4 h of feeding, an intravenous bolus of (2)H5-glycerol was administered to label VLDL1, VLDL2, and TAG. (13)C-glycerol tripalmitin was administered orally as an independent measure of CM TAG metabolism. Hepatic and intestinal lipoproteins were separated by an immunoaffinity method. In MetS, fed TAG and the increment in TAG from fasting to feeding were higher (P = 0.03 and P = 0.04, respectively) than in lean men. Fed CM, VLDL1, and VLDL2 TAG pool sizes were higher (P = 0.006, P = 0.03, and P < 0.02, respectively), and CM, VLDL1, and VLDL2 TAG production rates were higher (P < 0.002, P < 0.05, and P = 0.06, respectively) than in lean men. VLDL1, VLDL2, and CM TAG clearance rates were not different between groups. In conclusion, prandial hypertriglyceridemia in men with MetS was due to an increased production rate of both VLDL and CM TAG. Since both groups received identical meals, this suggests that in MetS the intestine is synthesizing more TAG de novo for export in CMs.
authors.affiliation: Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K.
authors.forename: Fariba
authors.initials: F
authors.lastname: Shojaee-Moradie
authors.forename: Yuying
authors.initials: Y
authors.lastname: Ma
authors.forename: Shaoying
authors.initials: S
authors.lastname: Lou
authors.forename: Roman
authors.initials: R
authors.lastname: Hovorka
authors.forename: A Margot
authors.initials: AM
authors.lastname: Umpleby
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000502:physiology; D002914:Chylomicrons / Q000378:metabolism*; D005215:Fasting; D006801:Humans; D015228:Hypertriglyceridemia / Q000150:complications / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000378:metabolism*; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology*; D014280:Triglycerides / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D002914:Chylomicrons; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C030106:very low density lipoprotein triglyceride