Investigation of lipid peroxidation in human low density lipoprotein.
Human plasma low density lipoprotein (LDL) exposed to oxygen saturated buffer becomes depleted of alpha-tocopherol within 3 to 6 hours. Thereafter, lipid peroxidation commences as evidenced by the loss of 18:2 (67 nmol/mg LDL) and 20:4 (12 nmol/mg LDL) and the concomitant formation of 4-hydroxynonenal (0.28 nmol/mg LDL) and fluorescent compounds. The major fluorophor in apo B of oxidized LDL has an excitation maximum at 355 nm and an emission maximum at 430 nm. A fluorophor with the same spectral properties is produced in apo B, if LDL is incubated with 4-hydroxynonenal, whereas malonaldehyde gives a fluorophor with excitation and emission maxima at 400/470 nm. Three-dimensional fluorescence spectroscopy proved to be an useful tool in analysing the complex fluorescence of apo B.
D000447:Aldehydes / Q000378:metabolism; D001055:Apolipoproteins B / Q000097:blood; D002021:Buffers; D006801:Humans; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014810:Vitamin E / Q000378:metabolism
D000447:Aldehydes; D001055:Apolipoproteins B; D002021:Buffers; D008077:Lipoproteins, LDL; D014810:Vitamin E; C027576:4-hydroxy-2-nonenal