Macrophages actively accumulate malonyldialdehyde-modified but not enzymatically oxidized low density lipoprotein.

Russian Cardiology Research Complex, 3rd Cherepkovskaya street, 15a, Moscow, Russia 121552.
Molecular and Cellular Biochemistry (Impact Factor: 2.39). 02/2012; 365(1-2):93-8. DOI: 10.1007/s11010-012-1247-5
Source: PubMed

ABSTRACT In this study, we show that low density lipoproteins (LDL) from human blood plasma which was oxidized by animal C-15 lipoxygenase is taken up by cultivated human macrophages with the same effectiveness as with non-oxidized (native) LDL. At the same time malonyldialdehyde-modified LDL is captured by cultivated macrophages very actively. Based on differences in catabolism of LDL with various levels of primary and secondary products of free-radical oxidation, it was offered to discriminate between the oxidized LDL itself (lipohydroperoxide-rich LDL) and the LDL that was chemically modified by free-radical oxidation secondary products of aldehyde nature. In this respect, aldehyde-modified but not oxidized (lipohydroperoxide-containing) LDL is atherogenic.

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