Enrichment with apolipoprotein E characterizes postprandial TG-rich lipoproteins in patients with non-insulin-dependent diabetes mellitus and coronary artery disease: a preliminary report.
An oral fat-load test was carried out in patients with non-insulin-dependent diabetes mellitus (NIDDM) and angiographically verified coronary artery disease (CAD; group 1, n = 6); in patients with CAD but no diabetes (group 2, n = 6); in patients with NIDDM but no CAD (group 3, n = 4); and in healthy control subjects (group 4, n = 4). Concentrations of apolipoprotein (apo) E, apo C-II, triglyceride (TG), retinyl palmitate, and cholesterol were measured in fasting plasma and in plasma obtained after 2, 4, 6, 9, and 24 h after a meal containing 78 g of fat and 345,000 IU of vitamin A. The same measurements were carried out in the lipoprotein fractions with Svedberg flotation rates Sf 400-1100, 60-400, 20-60 and 12-20, obtained by density gradient ultracentrifugation. The postprandial apo E concentrations were highest in group 1 (NIDDM and CAD) in plasma and in the TG-rich lipoprotein fractions, with significant differences in comparison with the healthy subjects. As shown by apo E to TG ratios, the postprandial lipoproteins were enriched with apo E in the patients with NIDDM and CAD. The largest excesses of apo E in group 1 patients were observed in the atherogenic Sf 12-60 lipoproteins. Across the entire study population, there was a significant inverse correlation between the postprandial apo E responses and the postheparin lipoprotein lipase activity. The results suggest that enrichment of the remnant lipoproteins with apo E may have a role in the increased risk of CAD among patients with NIDDM.
Syvänne
M
M
First Department of Medicine, University of Helsinki, Finland.
Rosseneu
M
M
Labeur
C
C
Hilden
H
H
Taskinen
M R
MR
D053304:Apolipoprotein C-II; D001056:Apolipoproteins C / Q000378:metabolism; D001057:Apolipoproteins E / Q000378:metabolism*; D002914:Chylomicrons / Q000097:blood; D003327:Coronary Disease / Q000097:blood* / Q000150:complications; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications; D004435:Eating; D005260:Female; D006801:Humans; D008049:Lipase / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D008079:Lipoproteins, VLDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood*; D014461:Ultracentrifugation
D053304:Apolipoprotein C-II; D001056:Apolipoproteins C; D001057:Apolipoproteins E; D002914:Chylomicrons; D008074:Lipoproteins; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C030106:very low density lipoprotein triglyceride; D008049:Lipase