Fat ingestion is associated with increased levels of apoC-III- and apoE-B-containing lipoprotein particles in humans.

Apolipoprotein (apo) C-III and apoE have a major influence on post-prandial apoB-containing lipoprotein metabolism. The goal of the present study was to compare the post-prandial changes in particles containing apoB and apoC-III and those containing apoB and apoE. Twenty subjects consumed a fatty meal (1 g of fat kg-1). Human lipoprotein particles were measured by enzyme-linked immunosorbent assay (ELISA) using combinations of anti-apoC-III, -apoE and -apoB. Post-prandial lipaemia was associated with an increase in LpC-III:B (+100%) and LpE:B (+55%; P < 0.05), which occurred 4.07 +/- 1.2 and 4.7 +/- 0.8 h after the meal respectively (P < 0.05). Gel filtration chromatography showed that fasting plasma LpC-III:B and LpE:B eluted in two fractions consisting of large and smaller sized particles; 3 h after the meal, LpC-III:B and LpE:B increased in the very low-density lipoprotein (VLDL) + intermediate-density lipoprotein (IDL) fraction; at 6 h, LpC-III:B and LpE:B decreased in VLDL and LpE:B increased moderately in the low-density lipoprotein (LDL) size range; at 10 h, both concentrations of lipoprotein particles returned to fasting levels. In conclusion, apoC-III-B-containing and apoE-B-containing lipoproteins have different post-prandial metabolic fates. These differences may result in different atherogenic potential.