Ultraviolet-treated lipoproteins as a model system for the study of the biological effects of lipid peroxides on cultured cell. I. Chemical modifications of ultraviolet-treated low-density lipoproteins.

  title={Ultraviolet-treated lipoproteins as a model system for the study of the biological effects of lipid peroxides on cultured cell. I. Chemical modifications of ultraviolet-treated low-density lipoproteins.},
  author={Nicole Dousset and Anne N{\`e}gre-Salvayre and M L{\'o}pez and Robert Salvayre and Louis Douste‐Blazy},
  journal={Biochimica et biophysica acta},
  volume={1045 3},


Under all the conditions used, apoB was not affected by the UV radiations as shown by the stability of amino acid composition and of trinitrobenzenesulfonic acid reactive amino group content, and the low density lipoprotein size was not altered.

Subcellular Alterations Induced by UV-Oxidized Low-Density Lipoproteins in Epithelial Cells Can Be Counteracted by α-Tocopherol

The results presented here could be of relevance for a better comprehension of the pathogenic mechanisms of several human diseases, including dermatological pathologies, and could indicate that antioxidants such as α-tocopherol could represent an important therapeutic challenge in the maintenance of cell and tissue homeostasis in the long run.

Recycling of vitamin E in human low density lipoproteins.

It is suggested that the recycling of vitamin E and other phenolic antioxidants by plasma reductants may be an important mechanism for the enhanced antioxidant protection of LDL.

In vitro cell injury by oxidized low density lipoprotein involves lipid hydroperoxide-induced formation of alkoxyl, lipid, and peroxyl radicals.

Cell death was postulated to occur due to lipid peroxidation via a sequence involving lipid hydroperoxide-induced, iron-mediated formation of alkoxyl, lipid, and peroxyl radicals, consistent with current theories linking lipoprotein oxidation to atherosclerosis.

Oxidized Low Density Lipoprotein Reduces Thrombomodulin Transcription in Cultured Human Endothelial Cells through Degradation of the Lipoprotein in Lysosomes (*)

Results suggested that down-regulation of TM on endothelial cells exposed to oxidized LDL resulted from inhibition of its transcription mediated by lysosomal degradation of oxidization LDL and that a lipid component in the LDL could be an active species.



Enzymatic modification of low density lipoprotein by purified lipoxygenase plus phospholipase A2 mimics cell-mediated oxidative modification.

It is shown that incubation of LDL with purified soybean lipoxygenase, in the presence of pure phospholipase A2, can mimic endothelial cell-induced oxidative modification, and represents the first example of oxidative modification of LDL by specific enzymes leading to enhanced recognition by macrophages.

Studies on oxidized low density lipoproteins. Controlled oxidation and a prostaglandin artifact.

Low density lipoproteins (LDL), isolated by ultracentrifugal flotation, were oxidized slowly during dialysis against 0.15 M NaCl and subsequent incubation in 96% air-4% CO2 at 37 degrees C and cross-reacting material in LDLOXID preparations was evidently formed from the oxidation of free fatty acids released from LDL.

Autoxidation of human low density lipoprotein: loss of polyunsaturated fatty acids and vitamin E and generation of aldehydes.

The rate and extent of the change of LDL constituents occurring during lipid peroxidation is reported for the first time, and 4-hydroxynonenal was most effective, followed by 2,4-heptadienal, hexanal, and malonaldehyde.

Macrophage Oxidation of Low Density Lipoprotein Generates a Modified Form Recognized by the Scavenger Receptor

The degradation of 125l-labeled macrophage-modified LDL by macrophages was competitively inhibited by unlabeled acetyl LDL or unlabeling endothelial cell-modified HDL but not by native LDL, indicating that the degradation was mediated by the acetyl HDL receptor.

The scavenger cell pathway for lipoprotein degradation: specificity of the binding site that mediates the uptake of negatively-charged LDL by macrophages.

It is possible that the site that binds negatively-charged LDL may be responsible for the massive accumulation of cholesteryl esters that occurs in vivo in macrophages and other scavenger cells in patients with high levels of circulating plasma LDL.

Probucol inhibits oxidative modification of low density lipoprotein.

The findings suggest the hypothetical but intriguing possibility that probucol, in addition to its recognized effects on plasma LDL levels, may inhibit atherogenesis by limiting oxidative LDL modification and thus foam cell formation and/or EC injury.

Lipoprotein Oxidation and Lipoprotein‐lnduced Cytotoxicity

It is indicated that when human VLDL or LDL Is prepared under conditions allowing oxidation, such oxidation renders the molecular complexes highly toxic to human skin flbroblasta growing In culture.