An (1)O2 route to γ-hydroxyalkenal phospholipids by vitamin E-induced fragmentation of hydroperoxydiene-derived endoperoxides.

ABSTRACT: Biologically active phospholipids that incorporate an oxidatively truncated acyl chain terminated by a γ-hydroxyalkenal are generated in vivo. The γ-hydroxyalkenal moiety protrudes from lipid bilayers like whiskers that serve as ligands for the scavenger receptor CD36, fostering endocytosis, e.g., of oxidatively damaged photoreceptor cell outer segments by retinal pigmented endothelial cells. They also covalently modify proteins generating carboxyalkyl pyrroles incorporating the ε-amino group of protein lysyl residues. We postulated that γ-hydroxyalkenals could be generated, e.g., in the eye, through fragmentation of hydroperoxy endoperoxides produced in the retina through reactions of singlet molecular oxygen with polyunsaturated phospholipids. Since phospholipid esters are far more abund

SUBMITTER: Gu X 

PROVIDER: S-EPMC3141739 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature