title: Significance of amino groups of phosphatidylethanolamine in phospholipid peroxidation of mixed liposomes.
abstract: The effect of distribution of phosphatidylethanolamine (PE) in multilamellar vesicles (MLV) on their peroxidative susceptibility was studied. Liposomes containing various ratios of L-alpha-dilinoleoyl phosphatidylcholine (DiLinPC) and L-alpha-dilinoleoyl phosphatidylethanolamine (DiLinPE) were peroxidized by ferrous ion or a water-soluble radical initiator 2,2'-azobis (2-amidino-propane) dihydrochloride (AAPH). The oxygen consumption rate was compared with the formation kinetics of fluorescent products. Inclusion of PE in liposomes was found to accelerate the Fe(2+)-dependent peroxidation. Modification of the amino group of PE with 2,4,6-trinitrobenzenesulfonic acid (TNBS) inhibited Fe(2+)-induced oxygen consumption in the late stage where fluorescent substances formed. A possible role of the amino group of PE on lipid peroxidation is discussed, especially in terms of its reactivity with oxidation products and subsequent formation of fluorescent substances.
authors.affiliation: Biophysics Laboratory, Institute of Physical and Chemical Research, Saitama, Japan.
authors.forename: J Y
authors.initials: JY
authors.lastname: Wang
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Wang
authors.forename: T
authors.initials: T
authors.lastname: Kouyama
authors.forename: T
authors.initials: T
authors.lastname: Shibata
authors.forename: T
authors.initials: T
authors.lastname: Ueki
mesh_terms: D000578:Amidines / Q000737:chemistry; D000818:Animals; D005296:Ferrous Compounds / Q000737:chemistry; D007700:Kinetics; D015227:Lipid Peroxidation; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D010101:Oxygen Consumption; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014302:Trinitrobenzenesulfonic Acid / Q000737:chemistry
chemical_list: D000578:Amidines; D005296:Ferrous Compounds; D008081:Liposomes; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; C038191:1,2-dilinoleoyl-3-phosphatidylethanolamine; C046728:2,2'-azobis(2-amidinopropane); D014302:Trinitrobenzenesulfonic Acid