title: Increased hepatic secretion of very-low-density lipoprotein apolipoprotein B-100 in obesity: a stable isotope study.
abstract: 1. We measured the hepatic secretion of very-low-density lipoprotein apolipoprotein B-100 (VLDL apoB) using a stable-isotope gas chromatography-mass spectrometry method in six obese subjects [three males, three females, age 41.5 +/- 3.4 years (mean +/- SEM), weight 105.0 +/- 4.8 kg, plasma total cholesterol concentration 6.2 +/- 0.4 mmol/l, triacylglycerol 2.8 +/- 0.8 mmol/l, high-density lipoprotein cholesterol 1.0 +/- 0.2 mmol/l] and six lean control subjects (three males, three females, age 41.8 +/- 3.7 years, weight 68.2 +/- 4.9 kg, total cholesterol concentration 4.5 +/- 0.3 mmol/l, triacylglycerol 0.8 +/- 0.2 mmol/l, high-density lipoprotein cholesterol 1.3 +/- 0.1 mmol/l). 2. Plasma total cholesterol, triacylglycerol and mevalonic acid (an index of cholesterol synthesis in vivo) concentrations were significantly higher in the obese subjects than in control subjects (P = 0.02, P = 0.03, P = 0.04, respectively). VLDL apoB pool size and absolute secretion rate were significantly higher in the obese subjects than in control subjects (323.4 +/- 99.8 mg versus 53.6 +/- 17.1 mg, P = 0.004; and 42.3 +/- 13.8 mg kg fat-free mass-1 day-1 versus 10.7 +/- 0.4 mg kg fat-free mass-1 day-1, P = 0.01), but there was no significant difference in the fractional catabolic rate of VLDL apoB.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, St. Thomas' Hospital (UMDS), London, U.K.
authors.forename: M H
authors.initials: MH
authors.lastname: Cummings
authors.forename: G F
authors.initials: GF
authors.lastname: Watts
authors.forename: C
authors.initials: C
authors.lastname: Pal
authors.forename: M
authors.initials: M
authors.lastname: Umpleby
authors.forename: T R
authors.initials: TR
authors.lastname: Hennessy
authors.forename: R
authors.initials: R
authors.lastname: Naoumova
authors.forename: P H
authors.initials: PH
authors.lastname: Sönksen
mesh_terms: D000328:Adult; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B / Q000032:analysis / Q000378:metabolism*; D002096:C-Peptide / Q000097:blood; D002784:Cholesterol / Q000097:blood; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007328:Insulin / Q000097:blood; D008099:Liver / Q000378:metabolism*; D008297:Male; D008798:Mevalonic Acid / Q000097:blood; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000378:metabolism*; D014280:Triglycerides / Q000097:blood
chemical_list: D053299:Apolipoprotein B-100; D001055:Apolipoproteins B; D002096:C-Peptide; D007328:Insulin; D014280:Triglycerides; D002784:Cholesterol; D008798:Mevalonic Acid