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Title: Effect of proteolysis of low-density serum lipoproteins on their interaction with macrophages

Abstract

The authors previously postulated, on the basis of changes observed in the structural stability of low-density lipoproteins during treatment with pepsin or aortic cathepsin, that enzymatic modifications may lead to potentiation of the atherogenic properties of the lipoproteins. They also reported that treatment of lipoproteins with trypsin causes an increase in their binding with aortic glycosaminoglycans and to increased degradation by fibroblasts of patients with hereditary hypercholesterolemia. Limited proteolysis of lipoproteins with pepsin facilitated their binding with fibronectin. In this paper the authors investigate the uptake and degradation of low-density lipoproteins by macrophages after their limited hydrolysis by pepsin, an analog of tissue cathepsin D. The lipoproteins were isolated from the serum of healthy blood donors by ultracentrifugation. Iodination of the proteins with I 125 was carried out by the iodine monochloride method. Uptake and retention of the labelled lipoprotein were measured with a gamma counter. The increased uptake of the proteins, partially hydrolized by pepsin, was accompanied by their more intense degradation by macrophages.

Authors:
; ; ;
Publication Date:
Research Org.:
Institute of Biological and Medical Chemistry, Moscow, USSR
OSTI Identifier:
6438344
Resource Type:
Journal Article
Resource Relation:
Journal Name: Bull. Exp. Biol. Med. (Engl. Transl.); (United States); Journal Volume: 102:8; Other Information: Translated from Byulleten' Eksperimental'noi Biologii Meditsiny; 102: No. 8, 148-150(Aug 1986)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; LIPOPROTEINS; PROTEOLYSIS; UPTAKE; MACROPHAGES; RADIOASSAY; PEPSIN; ENZYME ACTIVITY; BLOOD CELLS; BLOOD CHEMISTRY; BLOOD SERUM; CATABOLISM; CELL CULTURES; ENZYMATIC HYDROLYSIS; IODINE 125; LABELLED COMPOUNDS; LABELLING; RETENTION; ACID PROTEINASES; ANIMAL CELLS; BETA DECAY RADIOISOTOPES; BIOLOGICAL MATERIALS; BLOOD; BODY FLUIDS; CHEMICAL REACTIONS; CONNECTIVE TISSUE CELLS; DAYS LIVING RADIOISOTOPES; DECOMPOSITION; ELECTRON CAPTURE RADIOISOTOPES; ENZYMES; HYDROLASES; HYDROLYSIS; INTERMEDIATE MASS NUCLEI; IODINE ISOTOPES; ISOTOPES; LIPIDS; LYSIS; MATERIALS; METABOLISM; NUCLEI; ODD-EVEN NUCLEI; ORGANIC COMPOUNDS; PEPTIDE HYDROLASES; PHAGOCYTES; PROTEINS; RADIOISOTOPES; SOLVOLYSIS; SOMATIC CELLS; 550501* - Metabolism- Tracer Techniques; 550201 - Biochemistry- Tracer Techniques

Citation Formats

Karmanskii, I.M., Kovaleva, G.G., Viktorova, L.N., and Shpikiter, V.O. Effect of proteolysis of low-density serum lipoproteins on their interaction with macrophages. United States: N. p., 1987. Web.
Karmanskii, I.M., Kovaleva, G.G., Viktorova, L.N., & Shpikiter, V.O. Effect of proteolysis of low-density serum lipoproteins on their interaction with macrophages. United States.
Karmanskii, I.M., Kovaleva, G.G., Viktorova, L.N., and Shpikiter, V.O. 1987. "Effect of proteolysis of low-density serum lipoproteins on their interaction with macrophages". United States. doi:.
@article{osti_6438344,
title = {Effect of proteolysis of low-density serum lipoproteins on their interaction with macrophages},
author = {Karmanskii, I.M. and Kovaleva, G.G. and Viktorova, L.N. and Shpikiter, V.O.},
abstractNote = {The authors previously postulated, on the basis of changes observed in the structural stability of low-density lipoproteins during treatment with pepsin or aortic cathepsin, that enzymatic modifications may lead to potentiation of the atherogenic properties of the lipoproteins. They also reported that treatment of lipoproteins with trypsin causes an increase in their binding with aortic glycosaminoglycans and to increased degradation by fibroblasts of patients with hereditary hypercholesterolemia. Limited proteolysis of lipoproteins with pepsin facilitated their binding with fibronectin. In this paper the authors investigate the uptake and degradation of low-density lipoproteins by macrophages after their limited hydrolysis by pepsin, an analog of tissue cathepsin D. The lipoproteins were isolated from the serum of healthy blood donors by ultracentrifugation. Iodination of the proteins with I 125 was carried out by the iodine monochloride method. Uptake and retention of the labelled lipoprotein were measured with a gamma counter. The increased uptake of the proteins, partially hydrolized by pepsin, was accompanied by their more intense degradation by macrophages.},
doi = {},
journal = {Bull. Exp. Biol. Med. (Engl. Transl.); (United States)},
number = ,
volume = 102:8,
place = {United States},
year = 1987,
month = 1
}
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