Factors influencing Lp[a]- particle size as determined by gradient gel electrophoresis.
This study examined factors influencing the particle diameter of Lp[a]-, the low density lipoprotein (LDL)-like moiety of Lp[a], in 26 subjects chosen to provide a range of Lp[a] and triglyceride levels. Lp[a] and LDL fractions were isolated by vertical density ultracentrifugation. Lp[a] was further purified using a lysine-Sepharose affinity column and Lp[a]- obtained by incubating Lp[a] with dithiothreitol. Lp[a], LDL, and Lp[a]- fractions were run on 3-13% gradient gels to determine particle diameter. Lp[a] size correlated positively with LDL size (r = 0.62; P < 0.001), but the association between Lp[a]- size and LDL size was stronger (r = 0.82; P < 0.0001). Log triglyceride level correlated inversely with Lp[a]- size (r = -0.72; P < 0.0001) and LDL size (r = 0.69; P < 0.0001). HDL cholesterol level correlated positively with Lp[a]- size (r = 0.67; P < 0.0005) and LDL size (r = 0.64; P < 0.0005). The strong correlation between LDL size and Lp[a]- size may be due to extracellular utilization of circulating LDL in the production of Lp[a] or may reflect the same metabolic processes influencing both these particles once Lp[a] has been formed.
O'Neal
D
D
Department of Medicine, University of Melbourne, Australia.
Grieve
G
G
Rae
D
D
Dragicevic
G
G
Best
J D
JD
D001054:Apolipoproteins A / Q000032:analysis* / Q000097:blood / Q000276:immunology; D008078:Cholesterol, LDL / Q000032:analysis / Q000097:blood / Q000737:chemistry*; D002846:Chromatography, Affinity; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D004229:Dithiothreitol / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D015151:Immunoblotting; D017270:Lipoprotein(a) / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D008239:Lysine / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D010316:Particle Size; D013439:Sulfhydryl Reagents / Q000737:chemistry; D014461:Ultracentrifugation
D001054:Apolipoproteins A; D008078:Cholesterol, LDL; D017270:Lipoprotein(a); D013439:Sulfhydryl Reagents; D008239:Lysine; D004229:Dithiothreitol