Remnant Indices for Estimating Postprandial Lipidemia in Young Women

: Postprandial hyperglycemia is well established as a major risk factor for prediabetes and type 2 diabetes. However, for postprandial hyperlipidemia, no definitive criteria exist, and fasting values of lipids and lipoproteins had limited efficacy for estimating postprandial lipidemia. In the present study, we performed a fat-ingestion test and aimed to propose indices for estimating postprandial lipoprotein metabolism. Methods: Healthy young Japanese women (n=54, age 21.1 ± 1.0 y) with apolipoprotein E phenotype 3/3 were enrolled. They ingested fat cream (OFTT cream™, Jomo, Japan; 1 g/kg as cream, 0.35 g/kg as fat). Venous blood samples were taken before (0 h) and at 0.5, 1, 2, 4, and 6 h after ingestion. Results: The serum triglyceride (TG) level peaked at 2 h and returned to below baseline at 6 h. The remnant-like particle-TG (RP-TG) level increased at 1 h, peaked at 2 h, and returned to baseline at 6 h. The remnant lipoprotein-cholesterol (RLP-C) level increased at 2 h, peaked at 4 h, and returned to baseline at 6 h. The apolipoprotein B48 level increased at 1 h, peaked at 4 h, and did not return to baseline at 6 h. The apolipoprotein B100 concentration slightly decreased at 2 h and increased at 6 h. TG−RP-TG did not change during 6 h, but RP-TG/TG rose at 2–6 h compared to the fasting value. RP-TG/RLP-C increased at 2–4 h and returned to baseline at 6 h. Conclusion: After fat ingestion, while the concentration of non-remnant TG was stable, remnant TG increased. The content of TG per remnant particle increased up to 2 h and decreased from 2 h to 6 h, and the size became smaller. The remnant indices, RP-TG/TG and RP-TG/RLP-C, may be useful for estimating postprandial lipidemia.