title: Hypertriglyceridemic subjects exhibit an accumulation of small dense chylomicron particles in the fasting state.
abstract: OBJECTIVE
  Normocholesterolemic subjects with elevated fasting plasma triglycerides are at increased risk of atherosclerosis through mechanisms that are not yet delineated. We hypothesized that elevated plasma triglyceride is associated with increased vascular exposure to pro-atherogenic lipoprotein remnants. To test this hypothesis, the abundance, and size distribution of chylomicron particles were determined in individuals with and without hypertriglyceridemia.
  
  
  METHODS
  Twelve hypertriglyceridemic subjects (HTG group, triglyceride concentration ≥1.7 mmol/L) and twelve normotriglyceridemic subjects (NTG group) matched for age and gender were studied. The distribution of chylomicron particles was assessed by determining the fasting concentration of apo B-48 in serum lipoprotein fractions with Svedberg flotation rates of (Sf) > 400, Sf 20-400 and Sf < 20.
  
  
  RESULTS
  The total concentration of apo B-48 in subjects with HTG was almost twice that observed in NTG controls with ∼80% of the increase residing in the Sf < 20 fraction (HTG: 8.7 ± 1.0 μg/mL vs NTG: 5.0 ± 0.6 μg/mL; P = 0.016). Significantly greater concentrations of apo B-48 were also observed in the less dense Sf 20-400 (HTG: 1.1 ± 0.2 μg/mL vs NTG: 0.4 ± 0.07 μg/mL; P < 0.001) and the Sf > 400 (HTG: 1.1 ± 0.3 μg/mL vs NTG: 0.3 ± 0.04 μg/mL; P < 0.001) fractions. An accumulation of triglyceride was also observed across all lipoprotein fractions in HTG subjects compared to NTG (Sf 400 & Sf 20-400: P < 0.001 and Sf < 20: P = 0.013).
  
  
  CONCLUSIONS
  Normocholesterolemic, moderately hypertriglyceridemic subjects are at increased atherogenic risk due to greater apo B-48 concentration in the small, dense lipoprotein fraction.
authors.affiliation: School of Public Health, Faculty of Health Sciences, Curtin University, Bentley, GPO Box U1987, Perth, WA 6845, Australia; Faculty of Medicine, Mataram University, West Nusa Tenggara, Indonesia.
authors.forename: Deasy
authors.initials: D
authors.lastname: Irawati
authors.affiliation: School of Public Health, Faculty of Health Sciences, Curtin University, Bentley, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: John C L
authors.initials: JC
authors.lastname: Mamo
authors.affiliation: School of Public Health, Faculty of Health Sciences, Curtin University, Bentley, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: Mario J
authors.initials: MJ
authors.lastname: Soares
authors.affiliation: School of Public Health, Faculty of Health Sciences, Curtin University, Bentley, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: Karin M
authors.initials: KM
authors.lastname: Slivkoff-Clark
authors.affiliation: School of Public Health, Faculty of Health Sciences, Curtin University, Bentley, GPO Box U1987, Perth, WA 6845, Australia. Electronic address: T.P.James@curtin.edu.au.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: James
mesh_terms: D000368:Aged; D000886:Anthropometry; D053299:Apolipoprotein B-100 / Q000097:blood; D053283:Apolipoprotein B-48 / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D002914:Chylomicrons / Q000097:blood*; D003430:Cross-Sectional Studies; D005215:Fasting; D005260:Female; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood*; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008075:Lipoproteins, HDL / Q000097:blood; D008079:Lipoproteins, VLDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D010316:Particle Size; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D053299:Apolipoprotein B-100; D053283:Apolipoprotein B-48; D001786:Blood Glucose; D002914:Chylomicrons; D007328:Insulin; D008055:Lipids; D008075:Lipoproteins, HDL; D008079:Lipoproteins, VLDL; D014280:Triglycerides
keywords: Apolipoprotein B-48; Chylomicron; Hypertriglyceridemia; Lipoprotein fraction