title: Unusually high reactivity of apolipoprotein B-100 among proteins to radical reactions induced in human plasma.
abstract: Relative reactivities of proteins to radical reactions caused in human plasma were studied for the first time utilizing an immunoblotting assay. When radical reactions were caused by Cu(2+), apolipoprotein B-100 (apoB) underwent extensive fragmentation concurrently with the decrease in alpha-tocopherol, while human serum albumin (HSA) and transferrin (TF) were not decreased at all. When radical reactions were initiated by Cu(2+) with hydrogen peroxide or 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), alpha-tocopherol and apoB were also decreased steadily but HSA and TF were not decreased. These observations indicate that apoB is extremely reactive, even comparable to alpha-tocopherol, towards radical reactions. These results also suggest that the radical reaction of apoB is a possible process in vivo and it is involved in atherogenesis along with low density lipoprotein lipid peroxidation, which has been studied extensively.
authors.affiliation: Department of Food Science and Nutrition, Nara Women's University, Nara, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Hashimoto
authors.forename: S
authors.initials: S
authors.lastname: Narita
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Kojo
mesh_terms: D000578:Amidines / Q000494:pharmacology; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B / Q000097:blood* / Q000737:chemistry; D002413:Cations, Divalent; D003300:Copper / Q000494:pharmacology; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D015151:Immunoblotting; D015227:Lipid Peroxidation; D016877:Oxidants / Q000494:pharmacology; D011506:Proteins / Q000737:chemistry*; D012709:Serum Albumin / Q000032:analysis; D013997:Time Factors; D014168:Transferrin / Q000032:analysis; D014810:Vitamin E / Q000097:blood
chemical_list: D000578:Amidines; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B; D002413:Cations, Divalent; D016877:Oxidants; D011506:Proteins; D012709:Serum Albumin; D014168:Transferrin; D014810:Vitamin E; C046728:2,2'-azobis(2-amidinopropane); D003300:Copper; D006861:Hydrogen Peroxide