title: Degradation of phospholipids by oxidative stress--exceptional significance of cardiolipin.
abstract: The aim of this study was to investigate the effect of oxidative stress on mitochondrial phospholipids. In this context, this study investigated (i) the content of phosphatidylethanolamine (PE), phosphatidylcholine (PC) and cardiolipin (CL), (ii) the correlation of CL degradation with mitochondrial function and (iii) the correlation of CL degradation and CL oxidation. Oxidative stress induced by iron/ascorbate caused a dramatic decrease of these phospholipids, in which CL was the most sensitive phospholipid. Even moderate oxidative stress by hypoxia/reoxygenation caused a decrease in CL that was parallelled by a decrease in active respiration of isolated rat heart mitochondria. The relation between oxidative stress, CL degradation and CL oxidation was studied by in vitro treatment of commercially available CL with superoxide anion radicals and H2O2. The degradation of CL was mediated by H2O2 and required the presence of cytochrome c. Other peroxidases such as horse radish peroxidase and glutathione peroxidase had no effect. Cytochrome c in the presence of H2O2 caused CL oxidation. The data demonstrate that oxidative stress may cause degradation of phospholipids by oxidation, in particular CL; resulting in mitochondrial dysfunction.
authors.affiliation: Department of Pathological Biochemistry, Medical Faculty, Otto-von-Guericke-University Magdeburg, 39120 Magdeburg, Germany.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Wiswedel
authors.forename: Andreas
authors.initials: A
authors.lastname: Gardemann
authors.forename: Andreas
authors.initials: A
authors.lastname: Storch
authors.forename: Daniela
authors.initials: D
authors.lastname: Peter
authors.forename: Lorenz
authors.initials: L
authors.lastname: Schild
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D001921:Brain / Q000378:metabolism; D002308:Cardiolipins / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007501:Iron / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000494:pharmacology
chemical_list: D002308:Cardiolipins; D010743:Phospholipids; D013481:Superoxides; D006861:Hydrogen Peroxide; D007501:Iron; D001205:Ascorbic Acid