Evidence for in situ ethanolamine phospholipid adducts with hydroxy-alkenals.
Hydroxy-alkenals, such as 4-hydroxy-2(E)-nonenal (4-HNE; from n-6 fatty acids), are degradation products of fatty acid hydroperoxides, including those generated by free radical attack of membrane polyunsaturated fatty acyl moieties. The cytotoxic effects of hydroxy-alkenals are well known and are mainly attributable to their interaction with different molecules to form covalent adducts. Indeed, ethanolamine phospholipids (PEs) can be covalently modified in a cellular system by hydroxy-alkenals, such as 4-HNE, 4-hydroxy-2(E)-hexenal (4-HHE; from n-3 fatty acids), and 4-hydroxy-dodecadienal (4-HDDE; from the 12-lipoxygenase product of arachidonic acid), to form mainly Michael adducts. In this study, we describe the formation of PE Michael adducts in human blood platelets in response to oxidative stress and in retinas of streptozotocin-induced diabetic rats. We have successfully characterized and evaluated, for the first time, PEs coupled with 4-HHE, 4-HNE, and 4-HDDE by gas chromatography-mass spectrometry measurement of their ethanolamine moieties. We also report that aggregation of isolated human blood platelets enriched with PE-4-hydroxy-alkenal Michael adducts was altered. These data suggest that these adducts could be used as specific markers of membrane disorders occurring in pathophysiological states with associated oxidative stress and might affect cell function.
Bacot
Sandrine
S
Institut National de la Santé et de la Recherche Médicale U585, Institut National des Sciences Appliquées de Lyon, Lyon, France.
Bernoud-Hubac
Nathalie
N
Chantegrel
Bernard
B
Deshayes
Christian
C
Doutheau
Alain
A
Ponsin
Gabriel
G
Lagarde
Michel
M
Guichardant
Michel
M
D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D001792:Blood Platelets / Q000378:metabolism / Q000473:pathology; D002849:Chromatography, Gas; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide; D013058:Mass Spectrometry; D018384:Oxidative Stress; D010714:Phosphatidylethanolamines / Q000378:metabolism*; D051381:Rats; D012160:Retina / Q000378:metabolism / Q000473:pathology; D013311:Streptozocin
D000447:Aldehydes; D005231:Fatty Acids, Unsaturated; D010714:Phosphatidylethanolamines; D013311:Streptozocin; D006861:Hydrogen Peroxide