Biomaterial Database

Impaired cellular cholesterol efflux by oxysterol-enriched high density lipoproteins. 1997

L Gesquière, and N Loreau, and D Blache

INSERM CJF 93-10, Laboratoire de Biochimie des Lipoprotéines, Université de Bourgogne, Dijon, France.

One of the proposed antiatherogenicity role of high-density lipoproteins (HDL) is believed to stimulate removal of cholesterol from the peripheral cells back to the liver for excretion. We have investigated the effects of oxidation-related modifications of HDL on their ability to stimulate cholesterol efflux from cultured cells. Human HDL (HDL3, 1.13 < d < 1.21 g/ml) have been modified either by malondialdehyde or by copper-mediated oxidation (Ox-HDL3). Compared with native HDL3, the modified HDL3 resulted in a significantly reduced efflux of labeled cholesterol from preloaded macrophages (P388D1 cell line). Analysis of lipid composition of Ox-HDL3 by gas chromatography revealed the presence of oxysterols (OS). Enrichment of native HDL3 with oxysterols resulted in a reduced capacity to stimulate cholesterol efflux. The reduced ability of OS-enriched HDL3 to elicit cholesterol efflux may contribute to cellular cholesterol accumulation and subsequently to atherosclerosis.

UI	MeSH Term	Description	Entries
D007653	Ketocholesterols	Cholesterol substituted in any position by a keto moiety. The 7-keto isomer inhibits cholesterol uptake in the coronary arteries and aorta by blocking 3-hydroxy-3-methylglutaryl-CoA reductase activity.	Oxocholesterols
D008075	Lipoproteins, HDL	A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.	High Density Lipoprotein,High-Density Lipoprotein,High-Density Lipoproteins,alpha-Lipoprotein,alpha-Lipoproteins,Heavy Lipoproteins,alpha-1 Lipoprotein,Density Lipoprotein, High,HDL Lipoproteins,High Density Lipoproteins,Lipoprotein, High Density,Lipoprotein, High-Density,Lipoproteins, Heavy,Lipoproteins, High-Density,alpha Lipoprotein,alpha Lipoproteins
D008264	Macrophages	The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)	Bone Marrow-Derived Macrophages,Monocyte-Derived Macrophages,Macrophage,Macrophages, Monocyte-Derived,Bone Marrow Derived Macrophages,Bone Marrow-Derived Macrophage,Macrophage, Bone Marrow-Derived,Macrophage, Monocyte-Derived,Macrophages, Bone Marrow-Derived,Macrophages, Monocyte Derived,Monocyte Derived Macrophages,Monocyte-Derived Macrophage
D008315	Malondialdehyde	The dialdehyde of malonic acid.	Malonaldehyde,Propanedial,Malonylaldehyde,Malonyldialdehyde,Sodium Malondialdehyde,Malondialdehyde, Sodium
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D002849	Chromatography, Gas	Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.	Chromatography, Gas-Liquid,Gas Chromatography,Chromatographies, Gas,Chromatographies, Gas-Liquid,Chromatography, Gas Liquid,Gas Chromatographies,Gas-Liquid Chromatographies,Gas-Liquid Chromatography
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man