Enhanced Lipid Oxidation by Oxidatively Modified Myoglobin Role of Protein Bound Heme英文电子书.pdf

Biochemical and Biophysical Research Communications 269, 647–651 (2000) doi:10.1006/bbrc.2000.2349, available online at on Enhanced Lipid Oxidation by Oxidatively Modified Myoglobin: Role of Protein-Bound Heme Jennifer L. Vuletich,† Yoichi Osawa,†,1 and Michael Aviram* *Lipid Research Laboratory, Technion Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences and Rambam Medical Center, Haifa, Israel; and †Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan, 48109-0632 Received January 25, 2000 form Ox-LDL in the presence of hydrogen peroxide The formation of oxidized low density lipoprotein (7–12). The mechanisms proposed for this reaction in- (LDL) is believed to play a significant role in the clude the release of free heme, the formation of the pathogenesis of atherosclerosis. Myoglobin in the ferryl heme, and the formation of protein centered presence of H2O2 has been shown to catalyze LDL ox- radicals. Recent evidence with hemoglobin favors the idation in vitro. It is established that an oxidatively role of protein radicals in the formation of Ox-LDL (7). altered form of myoglobin (Mb-H), which contains a However, the role of oxidatively altered hemoprotein prosthetic heme covalently crosslinked to the apopro- products in the lipid peroxidation reaction has not been tein, is a major product in the reaction of native myo- addressed. globin with peroxides. In the current study, we have shown for the first time that Mb-H, in the absence of The reaction of hydrogen peroxide with myoglo