Peroxidation-induced perturbations of erythrocyte lipid organization.
Peroxidation of erythrocyte membrane lipids by hydrogen peroxide perturbs the lipid bilayer and increases phagocytosis by macrophages. This study addresses the underlying mechanism of these processes, and in particular the role of malondialdehyde, a major byproduct of lipid peroxidation. When erythrocytes were treated with hydrogen peroxide or ascorbate/iron to generate malondialdehyde, or with malondialdehyde itself, only those cells treated with hydrogen peroxide showed increased phospholipid spacing and enhanced phagocytosis. This result indicates that the alterations observed are unique to hydrogen peroxide treatment, and that malondialdehyde does not play a role in inducing these changes in surface properties. Comparison of adherence to human umbilical vein endothelial cells and phagocytosis showed that increased phagocytosis was not mirrored by enhanced adherence. This result suggests that two different signals may mediate recognition of erythrocytes by macrophages and by endothelial cells.
Pradhan
D
D
Department of Molecular and Cell Biology, Pennsylvania State University, University Park 16802.
Weiser
M
M
Lumley-Sapanski
K
K
Frazier
D
D
Kemper
S
S
Williamson
P
P
Schlegel
R A
RA
D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D004910:Erythrocyte Membrane / Q000187:drug effects*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008051:Lipid Bilayers; D015227:Lipid Peroxidation; D008264:Macrophages / Q000187:drug effects; D008314:Malonates / Q000494:pharmacology*; D008315:Malondialdehyde / Q000494:pharmacology*; D008563:Membrane Lipids / Q000502:physiology*; D010587:Phagocytosis / Q000187:drug effects; D010743:Phospholipids / Q000378:metabolism; D011744:Pyrimidinones; D013050:Spectrometry, Fluorescence
D008051:Lipid Bilayers; D008314:Malonates; D008563:Membrane Lipids; D010743:Phospholipids; D011744:Pyrimidinones; D008315:Malondialdehyde; C003954:merocyanine dye; D006861:Hydrogen Peroxide