High binding affinity of electronegative LDL to human aortic proteoglycans depends on its aggregation level

Cristina Bancells, Sònia Benítez, Matti Jauhiainen, Jordi Ordóñez-Llanos, Petri T. Kovanen, Sandra Villegas, José Luis Sánchez-Quesada, Katariina Öörni

Research output: Contribution to journalArticleResearchpeer-review

25 Citations (Scopus)

Abstract

Electronegative LDL [LDL(-)] is an atherogenic subfraction of plasma LDL that has increased apolipoprotein E (apoE) and apoC-III content, high density, and increased susceptibility to aggregation. These characteristics suggest that LDL(-) could bind to proteoglycans (PGs); therefore, our aim was to evaluate its affinity to PGs. Binding of LDL(-) and native LDL [LDL(+)] to human aortic PGs was determined by precipitation of LDL-glycosaminoglycan complexes, LDL incubation in PG-coated microtiter wells, and affinity chromatography on PG column. All methods showed that LDL(-) had higher binding affinity to PGs than did LDL(+). PG capacity to bind LDL(-) was increased approximately 4-fold compared with LDL(+) in precipitation and microtiter assays. Chromatography on PG column showed LDL(-) to consist of two subpopulations, one with higher and one with lower PG binding affinity than LDL(+). Unexpectedly, the lower PG affinity subpopulation had increased apoE and apoC-III content. In contrast, the high PG affinity subpopulation presented phospholipase C (PLC)-like activity and increased aggregation. These results suggest that PLC-like activity could alter LDL lipid composition, thereby promoting particle aggregation and binding to PGs. This propensity of a subpopulation of LDL(-) to bind to PGs could facilitate its retention in the extracellular matrix of arterial intima and contribute to atherosclerosis progression. Copyright © 2009 by the American Society for Biochemistry and Molecular Biology, Inc.
Original languageEnglish
Pages (from-to)446-455
JournalJournal of Lipid Research
Volume50
DOIs
Publication statusPublished - 1 Apr 2009

Keywords

  • Glycosaminoglycans
  • Lipoprotein aggregation
  • Phospholipase C
  • Sphingomyelinase

Fingerprint Dive into the research topics of 'High binding affinity of electronegative LDL to human aortic proteoglycans depends on its aggregation level'. Together they form a unique fingerprint.

Cite this