Biomaterial Database

[Metabolism and possible mechanisms of atherogenesis induced by lipoprotein (a)]. 1984

F Krempler

The mechanisms of atherogenesis are under intensive clinical and experimental investigation. It is commonly accepted that lipoproteins play a major role in atherogenesis. The results of several clinical studies suggest that lipoprotein (a) [Lp(a)] represents an independent risk factor for atherosclerosis. In order to obtain information on the physiological and pathological role of Lp(a), studies were undertaken to investigate the metabolism, removal sites, and possible atherogenic mechanisms of Lp(a). It was found that Lp(a) is not a metabolic product of other apoprotein B containing lipoproteins, but appears to be synthesized as a separate lipoprotein. The turnover parameters of Lp(a) resemble those of LDL. Binding studies of Lp(a) with cultured human fibroblasts demonstrated that Lp(a) is bound by the B-E receptor. After binding, Lp(a) is internalized and inhibits cellular cholesterol synthesis. In the presence of dextran sulfate or antibodies to the specific Lp(a) apoprotein or apoprotein B, Lp(a) is avidly taken up by macrophages. A similar mechanism might be responsible for the atherogenic effect of Lp(a).

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008074	Lipoproteins	Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.	Circulating Lipoproteins,Lipoprotein,Lipoproteins, Circulating
D008077	Lipoproteins, LDL	A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.	Low-Density Lipoprotein,Low-Density Lipoproteins,beta-Lipoprotein,beta-Lipoproteins,LDL(1),LDL(2),LDL-1,LDL-2,LDL1,LDL2,Low-Density Lipoprotein 1,Low-Density Lipoprotein 2,LDL Lipoproteins,Lipoprotein, Low-Density,Lipoproteins, Low-Density,Low Density Lipoprotein,Low Density Lipoprotein 1,Low Density Lipoprotein 2,Low Density Lipoproteins,beta Lipoprotein,beta Lipoproteins
D008079	Lipoproteins, VLDL	A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.	Pre-beta-Lipoprotein,Prebeta-Lipoprotein,Prebeta-Lipoproteins,Very Low Density Lipoprotein,Very-Low-Density Lipoprotein,Very-Low-Density Lipoproteins,Lipoprotein VLDL II,Lipoproteins, VLDL I,Lipoproteins, VLDL III,Lipoproteins, VLDL1,Lipoproteins, VLDL2,Lipoproteins, VLDL3,Pre-beta-Lipoproteins,Lipoprotein, Very-Low-Density,Lipoproteins, Very-Low-Density,Pre beta Lipoprotein,Pre beta Lipoproteins,Prebeta Lipoprotein,Prebeta Lipoproteins,VLDL Lipoproteins,VLDL1 Lipoproteins,VLDL2 Lipoproteins,VLDL3 Lipoproteins,Very Low Density 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
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D003327	Coronary Disease	An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.	Coronary Heart Disease,Coronary Diseases,Coronary Heart Diseases,Disease, Coronary,Disease, Coronary Heart,Diseases, Coronary,Diseases, Coronary Heart,Heart Disease, Coronary,Heart Diseases, Coronary
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
D006207	Half-Life	The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.	Halflife,Half Life,Half-Lifes,Halflifes
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man