The absence of any excess remnant accumulation in FHH subjects with varying 'impairment' of LDL receptor-mediated degradation of apo E-containing lipoproteins, permits the conclusion that chylomicron remnants are initially cleared from the plasma by apo E-recognizing receptors which are genetically distinct from LDL receptors. chylomicron remnants is mediated at the surfaces ofparen- chymal liver cells by apolipoprotein B, E (LDL) receptors coded for by a single allelic pair of genes on chromosome 19 Uptake . due, at least in part, to a loss of receptors which can recognize chylomicron remnants. Chylomicron Remnant: When the triglyceride reserve consumes (distributed), it converts APOC2 back to HDL (which APOE retains), leaving chylomicrons remnants of only 20-50 nm. Chylomicron: A lipoprotein rich in triglyceride and common in the blood during fat digestion and assimilation. Keywords: chylomicron remnants; dietary fat; LDL recep- Very low-density lipoprotein, or VLDL: Produced primarily by the liver, with smaller amounts contributed by the intestine. Lipoprotein-receptor related protein (LRP) requires apoE to facilitates the binding of the sequestered remnants to this receptor. fats; fatty acid metabolism; Share It On Facebook Twitter Email. Impaired clearance of chylomicron remnants correlates with increased vascular disease risk in FH. A. Apo A specific . This suggested the receptors were distinct. Information and translations of chylomicron remnants in the most comprehensive dictionary definitions resource on the web. Both apolipoprotein E and lipoprotein lipase are constituents of chylomicron remnants, another triglyceride-rich lipoprotein which has been proposed as a physiological ligand for the VLDL receptor. J. Lipid &S. 1997. 1982 Jan; 23 (1):42–52. Both type 1 and type 2 diabetes increase the risk of atherosclerotic cardiovascular disease (CVD). 1 Answer +1 vote . Several putative hepatic Moreover, it is impractical to use proper amounts of the tracer, because its tracee, chylomicron remnants, is virtually absent in the plasma of fasted mice (1, 34). Less clear the signifi- cance of the LDL receptor in clearance chylo- micron remnants. Moreover, a large number of people with prediabetes are at risk for developing frank diabetes worldwide. Supplementary key words chylomicron remnants chylomicron LDL receptor LDL receptor-related protein hepatic lipase heparan sulfate proteoglycan Consideration of lipoprotein metabolism has often been divided into endogenous and exogenous path- ways. Chylomicron remnants are enriched with endogenous TG fatty acids, compared with their parent chylomicrons, which consist primarily of exogenous TG fatty acids. Let’s compare Chylomicrons with other terms. The present studies of chylomicron metabolism were conducted in rabbits, since this species has been used extensively in lipoprotein studies. Definition of chylomicron remnants in the Definitions.net dictionary. In rabbits, the VLDL receptor has been found predomi-nantly in heart, skeletal muscle, and adipose tissue, but not in the liver [14]. 2 years ago | 08/07/2018 14:10:21 | gknowledge. What does chylomicron remnants mean? chylomicron remnants is influenced both by the fatty acid composition of the particles, and by longer-term adaptive changes in liver tissue, and suggest that the former effects are mediated mainly by the LDL receptor, while the latter may involve both the LDL receptor and the LRP. Evidence that chylomicron remnants and 6-VLDL are transported by the same receptor pathway in J774 murine macrophage-derived cells Jeff L. Ellsworth, Allen D. Cooper, and Fredric B. Kraemer' The concentration of chylomicron remnants used for This latter process allows the remnant to be taken up via the chylomicron remnant receptor. Science 264:1471–1474 CAS During glyceryl trioleate absorption in the rat, mucosal triacylglycerol (TG) fatty acids have been shown to consist of only 71% exogenous oleate. THE low-density-lipoprotein (LDL) receptor is a cell-surface pro-tein that plays an important part in the metabolism of cholesterol by mediating the uptake of LDL from plasma into cells1. D. Apo E specific. The two substances did not compete with each other for removal by the isolated perfused rat liver. Therefore, it was suggested that the VLDL receptor may play a role in the uptake of chylomicron remnants in non-hepatic tissues [13]. C. Apo C specific . The binding of chylomicron remnants was competitively inhibited in the presence of unlabeled remnants and to a lesser extent by unlabeled low-density lipoproteins. Previous. There are two types of receptors located in the hepatocyte membrane. Unlabeled chylomicron remnants did not reduce the binding of 125 I-asiaglycoprotein to plasma membranes, but did compete for 125 I-chylomicron remanant binding. Chylomicron remnants can then be taken up by hepatocytes via interaction with the LDL receptor which requires apoE. receptor is able to bind chylomicron remnants that are formed during the two-step pathway for chylomicron catabolism (1, 7). The VLDL receptor has been described as a new member of the LDL receptor supergene family that specifically binds VLDL in vitro via apolipoprotein E and lipoprotein lipase. Although both the LDL receptor and the LRP have been implicated in the uptake of chylomicron remnants, it has been difficult to determine which, if either, plays the dominant role in this process. VLDL contains relatively large amounts of triglycerides compared to protein. Cooper, A. D. Hepatic uptake of chylomicron remnants. Even with statin treatment to lower LDL cholesterol, patients with diabetes have a high residual CVD risk. The loss of regulation of cholesterol synthesis by die- tary cholesterol (1) has been well documented in trans- plantable hepatomas (2), in primary hepatomas from several species including man (3,4) and in premalignant liver (5, 6). Chylomicron remnants appear in the plasma only after fat ingestion, and never reach a steady state. Chylomicron remnants require four receptors for binding compared with one receptor per LDL particle [16], suggesting that with LDL receptor-deï¬ cient states, chylomicron remnant clearance may be more signiï¬ cantly compromised than LDL. In previous studies, chylomicron remnants or chylomicron remnant‐like particles (CRLPs) have been shown to induce extensive lipid accumulation in a variety of macrophage types, including the murine macrophage cell line J774 [], mouse peritoneal macrophages [], primary human monocyte‐derived macrophages [[3, 4]] and macrophages derived from the human monocyte cell line THP‐1 [[4, 5, 19, 20]]. The role of the LDL receptor in clearance of LDL is well established. [Google Scholar] Hui DY, Innerarity TL, Milne RW, Marcel YL, Mahley RW. J Lipid Res. Fats and Fatty Acid Metabolism. Chylomicron remnants bound to rabbit alveolar macrophages with high-affinity (Kd = 3.3 ± 0.71 μg of protein/mL). Diabetes is now a pandemic disease. Chylomicron remnants were degraded by alveolar macrophages from Watanabe heritable hyperlipidemic (WHHL) rabbits, which are devoid of LDL receptor activity. 38 2173-2192. Receptors for chylomicron remnants are (A) Apo A specific (B) Apo B-48 specific (C) Apo C specific (D) Apo E specific . Chylomicron Remnants Chylomicrons Apolipoprotein B-48 Lipoproteins, VLDL Receptors, LDL Lipoproteins Vitamin A Triglycerides Lymph Apolipoproteins E Liver Low Density Lipoprotein Receptor-Related Protein-1 Fetuins Apolipoproteins Corn Oil Cholesterol Emulsions Lipase Apolipoproteins B Cholesterol Esters Gold Colloid Lipoprotein Lipase Receptors, Lipoprotein Lactoferrin alpha … "Chylomicron Remnants" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings).Descriptors are arranged in a hierarchical structure, which enables searching at various levels of specificity. chylomicron remnants might provide a useful means of detecting subtle changes in LDL receptor expression. The publication costs of this article were defrayed in part by page charge payment. ical receptor for chylomicron remnants [13]. Meaning of chylomicron remnants. Because enterocytes have the apolipoprotein B-100/E receptor, this study was directed at determining whether the cells can take up and metabolize chylomicron remnants and, if so, whether this was receptor mediated. APOB48 and APOE are important for the identification of chylomicron remnants in the liver due to endocytosis and degradation. This article must therefore be hereby marked "advertise- B. Apo B-48 specific. Characterization of chylomicron remnant binding to rat liver membranes. These data demonstrate that in the perfused livers of normal mice at physiological concentrations, remnants are effi-ciently internalized by receptor-mediated endocytosis. Chylomicron remnants are the post-hydrolytic product of intestinally derived chylo- microns, which are responsible for the transport of dietary lipid [2]. In addition, while in the space of Disse chylomicron remnants can accumulate additional apoE that is secreted free into the space. When the lipoprotein remnants contact them they become bound and sequester (confined) against the hepatic cell membrane. Receptors for chylomicron remnants are? Moreover, colchicine and monensin which are endocytotic and lysozomal inhibitors, respectively, did not have any effect on the degradation of chylomicron remnants by macrophages from normal rabbits. Next . The converse also was true. remnants moved from the cell surface to the perinu-clear regions over this period (data not shown). Willnow TE, Sheng Z, Ishibashi S, Herz J (1994) Inhibition of hepatic chylomicron remnant uptake by gene transfer of a receptor antagonist. Binding of chylomicron remnants and beta-very low density lipoproteins to hepatic and extrahepatic lipoprotein receptors. The liver is the primary organ responsible for the clearance of pro-atherogeniclipoproteins, which include intermediate-density and low-density lipoproteins (IDL and LDL, respectively) and chylomicron remnants. 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