Biomaterial Database

Lipid peroxidation increases the molecular order of microsomal membranes. 1984

M T Curtis, and D Gilfor, and J L Farber

The effect of enzymatic lipid peroxidation on the molecular order of microsomal membranes was evaluated by ESR spectroscopy using the spin probes 5-, 12-, and 16-doxyl-stearic acid. Rat liver microsomal membranes were peroxidized by the NADPH-dependent reaction in the presence of the chelate ADP-Fe3+. Peroxidation resulted in a preferential depletion of polyenoic fatty acids and an increase in the percentage composition of shorter fatty acyl chains. There was no change in the cholesterol/phospholipid ratio of the peroxidized microsomes. The molecular order of both control and peroxidized membranes decreased toward the central region of the bilayer, and the order parameter (S) of each probe was temperature dependent. Peroxidation of the microsomal membrane lipids resulted in an increase in the order parameter determined with the three stearic acid spin probes. Of the three probes, 12-doxylstearic acid was the most sensitive to the changes in membrane organization caused by peroxidation. These data indicate that ESR spectroscopy is a sensitive method of detecting changes in membrane order accompanying peroxidation of membrane lipids.

UI	MeSH Term	Description	Entries
D008054	Lipid Peroxides	Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.	Fatty Acid Hydroperoxide,Lipid Peroxide,Lipoperoxide,Fatty Acid Hydroperoxides,Lipid Hydroperoxide,Lipoperoxides,Acid Hydroperoxide, Fatty,Acid Hydroperoxides, Fatty,Hydroperoxide, Fatty Acid,Hydroperoxide, Lipid,Hydroperoxides, Fatty Acid,Peroxide, Lipid,Peroxides, Lipid
D008563	Membrane Lipids	Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.	Cell Membrane Lipid,Cell Membrane Lipids,Membrane Lipid,Lipid, Cell Membrane,Lipid, Membrane,Lipids, Cell Membrane,Lipids, Membrane,Membrane Lipid, Cell,Membrane Lipids, Cell
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D008968	Molecular Conformation	The characteristic three-dimensional shape of a molecule.	Molecular Configuration,3D Molecular Structure,Configuration, Molecular,Molecular Structure, Three Dimensional,Three Dimensional Molecular Structure,3D Molecular Structures,Configurations, Molecular,Conformation, Molecular,Conformations, Molecular,Molecular Configurations,Molecular Conformations,Molecular Structure, 3D,Molecular Structures, 3D,Structure, 3D Molecular,Structures, 3D Molecular
D009249	NADP	Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)	Coenzyme II,Nicotinamide-Adenine Dinucleotide Phosphate,Triphosphopyridine Nucleotide,NADPH,Dinucleotide Phosphate, Nicotinamide-Adenine,Nicotinamide Adenine Dinucleotide Phosphate,Nucleotide, Triphosphopyridine,Phosphate, Nicotinamide-Adenine Dinucleotide
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D002621	Chemistry	A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
D004578	Electron Spin Resonance Spectroscopy	A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.	ENDOR,Electron Nuclear Double Resonance,Electron Paramagnetic Resonance,Paramagnetic Resonance,Electron Spin Resonance,Paramagnetic Resonance, Electron,Resonance, Electron Paramagnetic,Resonance, Electron Spin,Resonance, Paramagnetic
D005227	Fatty Acids	Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)	Aliphatic Acid,Esterified Fatty Acid,Fatty Acid,Fatty Acids, Esterified,Fatty Acids, Saturated,Saturated Fatty Acid,Aliphatic Acids,Acid, Aliphatic,Acid, Esterified Fatty,Acid, Saturated Fatty,Esterified Fatty Acids,Fatty Acid, Esterified,Fatty Acid, Saturated,Saturated Fatty Acids
D005260	Female		Females