Biomaterial Database

Dietary fish oil increases conversion of very low density lipoprotein apoprotein B to low density lipoprotein. 1989

M W Huff, and D E Telford

Department of Medicine, University Hospital, London, Ontario, Canada.

Dietary fish oils, which are rich in omega-3 fatty acids, are known to produce a marked lowering of very low density lipoprotein (VLDL) triglyceride concentrations, but they have a less marked effect on low density lipoprotein (LDL) cholesterol. Our previous apolipoprotein (apo) B kinetic studies in miniature pigs demonstrated that conversion of VLDL apo B to LDL apo B accounted for 15% to 20% of total VLDL apo B catabolism. In addition, 75% to 80% of LDL apo B was derived independent of plasma VLDL or intermediate density lipoprotein (IDL) apo B catabolism. The present studies were carried out to determine if fish-oil diets influenced: 1) the conversion of VLDL to LDL, and 2) the pathways of LDL apo B synthesis. Autologous 125I-VLDL and 131I-LDL were injected into four pigs after both a corn-oil (30 g/day for 18 days) and a Maxepa (30 g/day for 18 days) dietary period. Analysis of apo B specific activity curves demonstrated that fish oil reduced the VLDL pool size by 38% (p less than 0.05) due to an increase in fractional catabolic rate (0.83 +/- 0.13 vs. 0.48 +/- 0.03 hr-1), as the synthesis rate was unaffected. However, the proportion of VLDL apo B converted to LDL increased significantly (56 +/- 7% vs. 17 +/- 3%, p less than 0.01) whereas the proportion cleared directly decreased (46 +/- 5% vs. 83 +/- 3%, p less than 0.005). Fish oil reduced total LDL apo B synthesis (0.6 +/- 0.1 vs. 1.1 +/- 0.2 mg/hr/kg, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
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
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
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
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
D003314	Corn Oil	Oil from ZEA MAYS or corn plant.	Maize Oil,Lipomul,Corn Oils,Lipomuls,Maize Oils,Oil, Corn,Oil, Maize,Oils, Corn,Oils, Maize
D004041	Dietary Fats	Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.	Fats, Dietary,Dietary Fat,Fat, Dietary
D005395	Fish Oils	Oils high in unsaturated fats extracted from the bodies of fish or fish parts, especially the LIVER. Those from the liver are usually high in VITAMIN A. The oils are used as DIETARY SUPPLEMENTS. They are also used in soaps and detergents and as protective coatings.	Fish Liver Oils,Fish Oil,Liver Oils, Fish,Oil, Fish,Oils, Fish,Oils, Fish Liver
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001055	Apolipoproteins B	Major structural proteins of triacylglycerol-rich LIPOPROTEINS. There are two forms, apolipoprotein B-100 and apolipoprotein B-48, both derived from a single gene. ApoB-100 expressed in the liver is found in low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). ApoB-48 expressed in the intestine is found in CHYLOMICRONS. They are important in the biosynthesis, transport, and metabolism of triacylglycerol-rich lipoproteins. Plasma Apo-B levels are high in atherosclerotic patients but non-detectable in ABETALIPOPROTEINEMIA.	Apo-B,Apo B,ApoB,Apoprotein (B),Apoproteins B