Site-specific trapping of reactive species in low-density lipoprotein oxidation: biological implications. Biochim Biophys Acta 1993 Jun 12;1168(2):220-7
Date
06/12/1993Pubmed ID
8389205DOI
10.1016/0005-2760(93)90128-vScopus ID
2-s2.0-0027294970 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
Abundant data suggest that the oxidative modification of low-density lipoprotein is mediated by lipid-derived free radicals and aldehydes derived from them. In this report we have addressed the site-specific aspects of low-density lipoprotein modification. To this end, both water-soluble and lipid-soluble spin traps (i.e., diamagnetic organic molecules containing nitroso or nitrone functional groups) were used. Radical adducts were detected by electron spin resonance-spin trapping technique. Biochemical indices of low-density lipoprotein modification were thiobarbituric acid reactive substances formation, electrophoretic mobility and macrophage-mediated uptake of oxidized low-density lipoprotein. Results from this study have shown that the lipophilic spin trap, alpha-phenyl-tert-butyl-N-nitrone, traps a primary low-density lipoprotein lipid-derived radical, while also inhibiting the total oxidative modification in a dose-dependent manner. The more hydrophilic analog, i.e., alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone, appeared to trap the secondary alkyl radicals and did not exert any inhibitory effect on oxidative modification of low-density lipoprotein. The lipophilic nitroso spin trap, 2-methyl-2-nitroso propane, which traps a lipid-derived radical, inhibited the low-density lipoprotein modification as did the water-soluble nitroso analog, 2-hydroxymethyl-2-nitroso propane. However, the water-soluble nitroso analog did not trap the lipid radical. The inhibitory effect of 2-hydroxymethyl-2-nitroso propane was tentatively attributed to trapping of aldehydes. It is conceivable that spin traps can inhibit the oxidative modification of low-density lipoprotein by trapping of the lipid radicals as well as trapping aldehydes formed from lipid peroxidation.
Author List
Kalyanaraman B, Joseph J, Parthasarathy SAuthor
Balaraman Kalyanaraman PhD Professor in the Biophysics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsApolipoproteins B
Cell Line
Cyclic N-Oxides
Electron Spin Resonance Spectroscopy
Free Radicals
Humans
Lipid Peroxidation
Lipoproteins, LDL
Macrophages
Models, Chemical
Nitrogen Oxides
Nitroso Compounds
Oxidation-Reduction
Pyridines
Rabbits
Spin Labels
Thiobarbituric Acid Reactive Substances