Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1990-3-23
pubmed:abstractText
We investigated the roles of lipoprotein lipase and apolipoprotein E (apoE) secreted from human monocyte-derived macrophages in the uptake of very low density lipoproteins (VLDL). ApoCII-deficient VLDL were isolated from a patient with apoCII deficiency. The lipolytic conversion to higher density and the degradation of the apoCII-deficient VLDL by macrophages were very slight, whereas the addition of apoCII enhanced both their conversion and degradation. This suggests that the lipolysis and subsequent conversion of VLDL to lipoproteins of higher density are essential for the VLDL uptake by macrophages. VLDL incubated with macrophages obtained from subjects with E3/3 phenotype (E3/3-macrophages) showed a 17-fold greater affinity in inhibiting the binding of 2 micrograms/ml 125I-low density lipoprotein (LDL) to fibroblasts than native VLDL, whereas the incubation of VLDL with macrophages obtained from a subject with E2/2 phenotype (E2/2-macrophages) did not cause any increase in their affinity. Furthermore, 3 micrograms/ml 125I-VLDL obtained from a subject with E3/3 phenotype were degraded by E3/3-macrophages to a greater extent than by E2/2-macrophages (2-fold), indicating that VLDL uptake is influenced by the phenotype of apoE secreted by macrophages. From these results, we conclude that both lipolysis by lipoprotein lipase and incorporation of apoE secreted from macrophages alter the affinity of VLDL for the LDL receptors on the cells, resulting in facilitation of their receptor-mediated endocytosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3040-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:2303437-Apolipoprotein C-II, pubmed-meshheading:2303437-Apolipoproteins C, pubmed-meshheading:2303437-Apolipoproteins E, pubmed-meshheading:2303437-Biological Transport, pubmed-meshheading:2303437-Cells, Cultured, pubmed-meshheading:2303437-Female, pubmed-meshheading:2303437-Fibroblasts, pubmed-meshheading:2303437-Humans, pubmed-meshheading:2303437-Hyperlipoproteinemia Type III, pubmed-meshheading:2303437-Infant, pubmed-meshheading:2303437-Kinetics, pubmed-meshheading:2303437-Lipoprotein Lipase, pubmed-meshheading:2303437-Lipoproteins, pubmed-meshheading:2303437-Lipoproteins, VLDL, pubmed-meshheading:2303437-Macrophages, pubmed-meshheading:2303437-Male, pubmed-meshheading:2303437-Middle Aged, pubmed-meshheading:2303437-Monocytes, pubmed-meshheading:2303437-Phenotype, pubmed-meshheading:2303437-Reference Values, pubmed-meshheading:2303437-Skin
pubmed:year
1990
pubmed:articleTitle
Apolipoprotein E and lipoprotein lipase secreted from human monocyte-derived macrophages modulate very low density lipoprotein uptake.
pubmed:affiliation
Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
pubmed:publicationType
Journal Article