Please use this identifier to cite or link to this item: https://hdl.handle.net/20.500.11851/1847
Title: The effect of HDL-bound and free PON1 on copper-induced LDL oxidation
Authors: Bayrak, A.
Bayrak, T.
Bodur, E.
Kılınç, Kamer
Demirpençe, Ediz
31728
7031
Keywords: Paraoxonase
PON1 polymorphism
High density lipoprotein
Purification
Low-density lipoprotein oxidation
Issue Date: Sep-2016
Publisher: Elsevier
Source: Bayrak, A., Bayrak, T., Bodur, E., Kılınç, K., & Demirpençe, E. (2016). The effect of HDL-bound and free PON1 on copper-induced LDL oxidation. Chemico-biological interactions, 257, 141-146.
Abstract: Oxidative modification of LDL plays an important role in the development of atherosclerosis. High density lipoprotein (HDL) confers protection against atherosclerosis and the antioxidative properties of paraoxonase 1 (PON1) has been suggested to contribute to this effect of HDL. The PON1 exist in two major polymorphic forms (Q and R), which regulate the concentration and activity of the enzyme and alter its ability to prevent lipid oxidation. However, the association of Q192R polymorphism with PON1's capacity to protect against LDL lipoperoxidation is controversial. The aim of this study was to evaluate the effects of the purified PON1 Q192R and the partially purified HDL-bound PON1 Q192R isoenzymes (HDL-PON1 Q192R) on LDL oxidation, with respect to their arylesterase/homocysteine thiolactonase (HTLase) activities. Cupric ion-induced LDL oxidation was reduced up to 48% by purified PON1 Q192, but only 33% by an equivalent activity of PON1 R192. HDL-PON1 Q192 isoenzyme caused a 65% reduction, whereas HDL-PON1 R192 isoenzyme caused only 46% reduction in copper ion-induced LDL oxidation. These findings reflect the fact that PON1 Q and PON1 R allozymes may have different protective characteristics against LDL oxidation. The protection against LDL oxidation provided by HDL-PON1 Q192R isoenzymes is more prominent than the purified soluble enzymes. Inhibition of the Ca+2-dependent PON1 Q192R arylesterase/HTLase by the metal chelator EDTA, did not alter PON1's ability to inhibit LDL oxidation. These studies indicate that the active site involvement of the purified enzyme is not similar to the HDL-bound one, in terms of both PON1 arylesterase/HTLase activity and the protection of LDL from copper ion-induced oxidation. Moreover, PON1's ability to protect LDL from oxidation does not seem to require calcium. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
URI: https://hdl.handle.net/20.500.11851/1847
ISSN: 0009-2797
Appears in Collections:PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Temel Tıp Bilimleri Bölümü / Department of Basic Medical Sciences
WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Show full item record

CORE Recommender

SCOPUSTM   
Citations

7
checked on Dec 29, 2022

WEB OF SCIENCETM
Citations

8
checked on Sep 24, 2022

Page view(s)

20
checked on Dec 26, 2022

Google ScholarTM

Check

Altmetric


Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.