Detection of new epitopes formed upon oxidation of low-density lipoprotein, lipoprotein (a) and very-low-density lipoprotein. Use of an antiserum against 4-hydroxynonenal-modified low-density lipoprotein.
4-Hydroxynonenal (HNE) is a major aldehydic propagation product formed during peroxidation of unsaturated fatty acids. The aldehyde was used to modify freshly prepared human low-density lipoprotein (LDL). A polyclonal antiserum was raised in the rabbit and absorbed with freshly prepared LDL. The antiserum did not react with human LDL, but reacted with CuCl2-oxidized LDL and in a dose-dependent manner with LDL, modified with 1, 2 and 3 mM-HNE, in the double-diffusion analysis. LDL treated with 4 mM of hexanal or hepta-2,4-dienal or 4-hydroxyhexenal or malonaldehyde (4 or 20 mM) did not react with the antiserum. However, LDL modified with 4 mM-4-hydroxyoctenal showed a very weak reaction. Lipoprotein (a) and very-low-density lipoprotein were revealed for the first time to undergo oxidative modification initiated by CuCl2. This was evidenced by the generation of lipid hydroperoxides and thiobarbituric acid-reactive substances, as well as by a marked increase in the electrophoretic mobility. After oxidation these two lipoproteins also reacted positively with the antiserum against HNE-modified LDL.
Institut für Medizinische Biochemie, Karl-Franzens Universität Graz, Austria.
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Jürgens
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Ashy
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Esterbauer
D000328:Adult; D000447:Aldehydes; D003300:Copper / Q000494:pharmacology; D000939:Epitopes / Q000032:analysis*; D005260:Female; D006801:Humans; D007106:Immune Sera; D005779:Immunodiffusion; D017270:Lipoprotein(a); D008074:Lipoproteins / Q000097:blood* / Q000276:immunology*; D008077:Lipoproteins, LDL / Q000097:blood* / Q000276:immunology*; D008079:Lipoproteins, VLDL / Q000097:blood* / Q000276:immunology*; D008297:Male; D010084:Oxidation-Reduction
D000447:Aldehydes; D000939:Epitopes; D007106:Immune Sera; D017270:Lipoprotein(a); D008074:Lipoproteins; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D003300:Copper; C027576:4-hydroxy-2-nonenal; C029892:cupric chloride