Influence of remnant accumulation markers on plasma concentrations of two lipoprotein(a) subspecies (containing or free of apoE).
Lipoprotein(a) [Lp(a)], an atherosclerosis marker, has 2 subspecies differing in structure and composition that can easily be distinguished by the presence or absence of apolipoprotein E (apoE). The subspecies containing apo E [Lp(a):B:E] is found mainly in the very-low-density lipoprotein (VLDL) size range, while that free of apoE [Lp(a):B] is found mainly in the LDL size range. As little is known about the physiologic function of these subspecies, this study investigated Lp(a):B and Lp(a):B:E concentrations in a population of normotriglyceridemic and moderately hypertriglyceridemic subjects in fasting state and attempted to determine the parameters influencing their plasma concentrations. The subjects studied (n = 98) had a mean total Lp(a) concentration of 108 mg/dL (28 to 252, minimum to maximum), a mean Lp(a):B concentration of 92.6 mg/dL (5 to 254), and a mean Lp(a):B:E concentration of 15.6 mg/dL (0 to 137). These results indicate that Lp(a):B:E, even in normolipidemic subjects, constitutes a detectable part of total Lp(a), ie, a mean percentage of 16.2% (0% to 96%). Multiple stepwise regression analyses showed that triacylglycerol has no independent effect on the concentration of Lp(a) subspecies, and that remnant accumulation markers, such as the E/LpB:E molar ratio (number of apoE per particle containing both apoB and apoE) and apoE-LpB (mass of apoE bound to particles containing both apoB and apoE), have a strong independent effect on this concentration. A strong positive influence of E/LpB:E on Lp(a):B:E subspecies was noted, as well as a negative influence of apo E-LpB on Lp(a):B subspecies. Taken together, these results suggest that the apoE bound to LpB:E particles plays a dominant role in the concentration of Lp(a) subspecies and that a redistribution of Lp(a) subspecies occurs under the influence of the apoE content of triacylglycerol-rich lipoprotein particles.
Bach-Ngohou
K
K
Laboratoire de Biochimie fondamentale et appliquée, UFR de Pharmacie, Nantes, France.
Giraud
F
F
Krempf
M
M
Bard
J M
JM
D000328:Adult; D001057:Apolipoproteins E / Q000097:blood*; D015415:Biomarkers; D005215:Fasting / Q000097:blood; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood*; D008055:Lipids / Q000097:blood; D017270:Lipoprotein(a) / Q000097:blood; D008074:Lipoproteins / Q000097:blood; D008297:Male; D009994:Osmolar Concentration; D020033:Protein Isoforms / Q000097:blood; D012016:Reference Values
D001057:Apolipoproteins E; D015415:Biomarkers; D008055:Lipids; D017270:Lipoprotein(a); D008074:Lipoproteins; D020033:Protein Isoforms