Effect of bilayer charge on lipoprotein lipid exchange

Research output: Contribution to journalArticle

Abstract

Lipoproteins play a key role in the onset and development of atherosclerosis, the formation of lipid plaques at blood vessel walls. The plaque formation, as well as subsequent calcification, involves not only endothelial cells but also connective tissue, and is closely related to a wide range of cardiovascular syndromes, that together constitute the number one cause of death in the Western World. High (HDL) and low (LDL) density lipoproteins are of particular interest in relation to atherosclerosis, due to their protective and harmful effects, respectively. In an effort to elucidate the molecular mechanisms underlying this, and to identify factors determining lipid deposition and exchange at lipid membranes, we here employ neutron reflection (NR) and quartz crystal microbalance with dissipation (QCM-D) to study the effect of membrane charge on lipoprotein deposition and lipid exchange. Dimyristoylphosphatidylcholine (DMPC) bilayers containing varying amounts of negatively charged dimyristoylphosphatidylserine (DMPS) were used to vary membrane charge. It was found that the amount of hydrogenous material deposited from either HDL or LDL to the bilayer depends only weakly on membrane charge density. In contrast, increasing membrane charge resulted in an increase in the amount of lipids removed from the supported lipid bilayer, an effect particularly pronounced for LDL. The latter effects are in line with previously reported observations on atherosclerotic plaque prone regions of long-term hyperlipidaemia and type 2 diabetic patients, and may also provide some molecular clues into the relation between oxidative stress and atherosclerosis.

Details

Authors
  • Kathryn Louise Browning
  • Tania Kjellerup Lind
  • Selma Maric
  • Robert David Barker
  • Marité Cárdenas
  • Martin Malmsten
External organisations
  • Malmö University
  • Institut Laue Langevin
  • Uppsala University
  • University of Copenhagen
Original languageEnglish
Pages (from-to)117-125
Number of pages9
JournalColloids and Surfaces. B, Biointerfaces
Volume168
Publication statusPublished - 2018 Aug 1
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes