TY - JOUR
T1 - Effect of bilayer charge on lipoprotein lipid exchange
AU - Browning, Kathryn
AU - Lind, Tania Kjellerup
AU - Maric, Selma
AU - Barker, Robert David
AU - Cárdenas, Marité
AU - Malmsten, Martin
PY - 2018
Y1 - 2018
N2 - 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.
AB - 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.
KW - Atherosclerosis
KW - HDL
KW - LDL
KW - Lipid exchange
KW - Lipoprotein
KW - Neutron reflection
U2 - 10.1016/j.colsurfb.2018.01.043
DO - 10.1016/j.colsurfb.2018.01.043
M3 - Journal article
C2 - 29422308
AN - SCOPUS:85041618999
SN - 0927-7765
VL - 168
SP - 117
EP - 125
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
ER -
