The elevation of apoB in hypercholesterolemic patients is primarily attributed to the relative increase of apoB/Lp-PLA

• Published in: Journal of lipid research Vol. 54; no. 12; pp. 3394 - 3402
• Main Authors: Tellis, Constantinos C, Moutzouri, Eliza, Elisaf, Moses, Wolfert, Robert L, Tselepis, Alexandros D
• Format: Journal Article
• Language: English
• Published: United States 01-12-2013
• Subjects: 1-Alkyl-2-acetylglycerophosphocholine Esterase - blood; Adult; Aged; Apolipoproteins B - blood; Calibration; Female; Humans; Hypercholesterolemia - blood; Hypercholesterolemia - drug therapy; Hypercholesterolemia - enzymology; Male; Middle Aged; Simvastatin - therapeutic use; Young Adult; simvastatin; low density lipoprotein; lipoprotein-associated phospholipase A2-bound apolipoprotein B; hypercholesterolemia
• ISSN: 1539-7262
• DOI: 10.1194/jlr.M041806

Lipoprotein-associated phospholipase A₂ (Lp-PLA₂) is a risk factor of cardiovascular disease. Plasma Lp-PLA₂ is mainly associated with apolipoprotein (apo)B-containing lipoproteins, primarily with low density lipoproteins (LDLs). Importantly, only a proportion of circulating lipoproteins contain Lp-PLA₂. We determined the plasma levels of Lp-PLA₂-bound apoB (apoB/Lp-PLA₂) in patients with primary hypercholesterolemia. The effect of simvastatin therapy was also addressed. The plasma apoB/Lp-PLA₂ concentration in 50 normolipidemic controls and 53 patients with primary hypercholesterolemia at baseline and at 3 months posttreatment with simvastatin (40 mg/day) was determined by an enzyme-linked immunosorbent assay. The concentration of the apoB-containing lipoproteins that do not bind Lp-PLA₂ [apoB/Lp-PLA₂⁻] was calculated by subtracting the apoB/Lp-PLA₂ from total apoB. The apoB/Lp-PLA₂ levels were 3.6-fold higher, while apoB/Lp-PLA₂⁻ were 1.3-fold higher in patients compared with controls. After 3 months of simvastatin treatment apoB/Lp-PLA₂ and apoB/Lp-PLA₂⁻ levels were reduced by 52% and 33%, respectively. The elevation in apoB-containing lipoproteins in hypercholesterolemic patients is mainly attributed to the relative increase in the proatherogenic apoB/Lp-PLA₂, while simvastatin reduces these particles to a higher extent compared with apoB/Lp-PLA₂⁻. Considering that Lp-PLA₂ is proatherogenic, the predominance of apoB/Lp-PLA₂ particles in hypercholesterolemic patients may contribute to their higher atherogenicity and incidence of cardiovascular disease.