Linked Life Data

11855794

Source:http://linkedlifedata.com/resource/pubmed/id/11855794

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-2-21
pubmed:abstractText
We investigated the effect of incubation of high density lipoprotein (HDL) under hyperglycaemic conditions on lipid composition, physicochemical properties and activity of paraoxonase (PON), a calcium-dependent enzyme associated with HDL that contributes to the antiatherogenicity of this lipoprotein. HDL incubated for three days with various glucose concentrations (0-100 mM) had significant increases in thiobarbituric acid-reactive substances (TBARS) and conjugated dienes with respect to control HDL. These results suggest that lipid peroxidation accompanies HDL glycation in vitro. The susceptibility to lipid peroxidation was higher in HDL isolated from subjects with low HDL-paraxonase activity with respect to subjects with higher HDL-PON activity. The lipid compositional changes were associated with modifications of apoprotein conformation as shown by the red-shifted position of the maximum emission of tryptophan in treated HDL. The decrease in the Gp (generalized polarization) value and the red-shifted position of the maximum emission of Laurdan incorporated in treated HDL demonstrate modifications of order and polarity with respect to control HDL. The negative correlation established between the Gp value and TBARS demonstrates that the modifications in molecular order are likely related to the increase in lipid peroxidation products. The activity of paraoxonase was significantly decreased in HDL incubated at 37 degrees C; a greater decrease occurred in the presence of 50 mM and 100 mM glucose. This study demonstrates modifications of lipid composition, apoprotein conformation and physicochemical properties of HDL incubated in the presence of glucose. These modifications affect the activity of HDL-associated paraoxonase. The physicochemical properties of lipoproteins play a regulatory role in lipoprotein function. The modification of order and polarity of glycated HDL and the alterations in paraoxonase activity could potentially contribute to the accelerated atherosclerosis in diabetic patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0940-5429
pubmed:author
pubmed:issnType
Print
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
163-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Effect of glycation of high density lipoproteins on their physicochemical properties and on paraoxonase activity.
pubmed:affiliation
Institute of Biochemistry, Faculty of Medicine, University of Ancona, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't