Biomaterial Database

Formation of high density lipoprotein2-like particles during lipolysis of very low density lipoproteins in vitro. 1978

J R Patsch, and A M Gotto, and T Olivercrona, and S Eisenberg

The effects of lipolysis of human plasma very low density lipoprotein (VLDL) on the structure and composition of high density lipoproteins (HDL) have been investigated. Lipolysis was performed in a controlled system in vitro containing VLDL (d less than 1.006 g/ml) and HDL3 (d = 1.125-1.210 g/ml) from human plasma and lipoprotein lipase (EC 3.1.1.34) purified from bovine milk. Lipolysis of VLDL caused profound changes in HDL3. Protein, phospholipid, and cholesterol liberated from VLDL during its lipolysis were transferred to the HDL3 particles. As a consequence of this in vitro transfer, the chemical composition and biophysical properties of HDL3 were substantially altered. The newly formed particles exhibited a flotation rate (F01.20) of 6.7 and a hydrated density of 1.110 g/ml. The chemical composition closely resembled that of native HDL2, and their size was slightly larger than that of the precursor HDL3. When HDL3 and postlipolysis HDL2 were subjected to ultracentrifugation under flotation velocity and equilibrium conditions, both proved to be stable particles. These results, when extrapolated to in vivo conditions, suggest an important metabolic relationship between the levels of circulating VLDL and HDL2 in plasma. This relationship now permits a reasonable explanation for numerous in vivo observations in which the levels of VLDL and HDL2 change reciprocally.

UI	MeSH Term	Description	Entries
D008071	Lipoprotein Lipase	An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. The enzyme hydrolyzes triacylglycerols in chylomicrons, very-low-density lipoproteins, low-density lipoproteins, and diacylglycerols. It occurs on capillary endothelial surfaces, especially in mammary, muscle, and adipose tissue. Genetic deficiency of the enzyme causes familial hyperlipoproteinemia Type I. (Dorland, 27th ed) EC 3.1.1.34.	Heparin-Clearing Factor,Lipemia-Clearing Factor,Diacylglycerol Lipase,Diglyceride Lipase,Post-Heparin Lipase,Postheparin Lipase,Postheparin Lipoprotein Lipase,Factor, Heparin-Clearing,Factor, Lipemia-Clearing,Heparin Clearing Factor,Lipase, Diacylglycerol,Lipase, Diglyceride,Lipase, Lipoprotein,Lipase, Post-Heparin,Lipase, Postheparin,Lipase, Postheparin Lipoprotein,Lipemia Clearing Factor,Lipoprotein Lipase, Postheparin,Post Heparin Lipase
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
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
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001053	Apolipoproteins	Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.	Apolipoprotein