Epoxidation of plasmalogens: source for long-chain alpha-hydroxyaldehydes in subcellular fractions of bovine liver.
1. Masked long-chain alpha-hydroxyaldehydes were trapped in all subcellular fractions of bovine liver by application of pentafluorbenzyloxime derivatization [van Kuijk, Thomas, Stephens and Dratz (1986) Biochem. Biophys. Res. Commun. 139, 144-149] and quantified via GLC/MS using characteristic ion traces. 2. The chain-length profile of long-chain 2-hydroxyalkanales clearly indicates their relationship to plasmalogens as precursor molecules. 3. The previously postulated existence of alpha-acyloxyplasmalogens as precursor molecules of masked long-chain alpha-hydroxyaldehydes in bovine tissue lipids [Lutz and Spiteller (1991) Liebigs Ann. Chem. 1991, 563-567] was excluded. 4. The constant oxidation rate of plasmalogens in all subcellular fractions provides conclusive evidence for a non-enzymic plasmalogen epoxidation process (probably via hydroperoxy radicals). 5. The high reactivity of alpha-hydroxyaldehydes sheds some doubt on the postulation that plasmalogens protect mammalian cells against oxidative stress as postulated previously [Morand, Zoeller and Raetz (1988) J. Biol. Chem. 263, 11590-11596; Morand, Zoeller and Raetz (1988) J. Biol. Chem. 263, 11597-11606].
Loidl-Stahlhofen
A
A
Lehrstuhl Organische Chemie I, Universität Bayreuth, NW I, Germany.
Hannemann
K
K
Felde
R
R
Spiteller
G
G
D000447:Aldehydes / Q000032:analysis*; D000818:Animals; D002417:Cattle; D004852:Epoxy Compounds / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D008099:Liver / Q000737:chemistry*; D010955:Plasmalogens / Q000737:chemistry*; D013347:Subcellular Fractions / Q000737:chemistry
D000447:Aldehydes; D004852:Epoxy Compounds; D010955:Plasmalogens