Formation of N-(hexanoyl)ethanolamine, a novel phosphatidylethanolamine adduct, during the oxidation of erythrocyte membrane and low-density lipoprotein.
The primary amino groups of biomolecules such as aminophospholipids, as well as proteins, are the potential targets of covalent modifications by lipid peroxidation products; however, little attention has been paid to the modification of aminophospholipids such as phosphatidylethanolamine (PE). The purpose of this study was to characterize the formation of a novel modified phospholipid, N-(hexanoyl)phosphatidylethanolamine (HEPE), in the reaction of PE with lipid hydroperoxides using mass spectrometric analyses. Upon reaction of egg PE with 13-hydroperoxyoctadecadienoic acid or other oxidized polyunsaturated fatty acids followed by phospholipase D-mediated hydrolysis, the formation of N-(hexanoyl)ethanolamine (HEEA), a head group of HEPE, was confirmed by isotope dilution liquid chromatography/tandem mass spectrometry. Moreover, increasing HEEA was detected in the hydrolysates of oxidized erythrocyte ghosts and low-density lipoprotein with their increasing lipid peroxidation levels. Collectively, these results suggest that the N-hexanoylated product of phospholipid, HEPE, can be generated during lipid peroxidation and may serve as one mechanism for the covalent modification of aminophospholipids in vivo.
Tsuji
Kentaro
K
Laboratory of Food and Biodynamics, Graduate School of Bioagricultural Sciences, Nagoya University, 464-8601, Nagoya, Japan.
Kawai
Yoshichika
Y
Kato
Yoji
Y
Osawa
Toshihiko
T
D000818:Animals; D004910:Erythrocyte Membrane / Q000737:chemistry / Q000378:metabolism*; D004983:Ethanolamines; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D008054:Lipid Peroxides / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010714:Phosphatidylethanolamines / Q000737:chemistry / Q000378:metabolism*; D010739:Phospholipase D / Q000378:metabolism
D004983:Ethanolamines; D005227:Fatty Acids; D008054:Lipid Peroxides; D008077:Lipoproteins, LDL; D010714:Phosphatidylethanolamines; D010739:Phospholipase D