<?xml version="1.0" encoding="UTF-8"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-10-19T01:09:22Z</responseDate><request verb="GetRecord" identifier="oai:ebyu-rdlopen.rawdatalibrary.net:ebyu/13303" metadataPrefix="oai_dc">https://ebyu-rdlopen.rawdatalibrary.net/oai/request</request><GetRecord><record><header><identifier>oai:ebyu-rdlopen.rawdatalibrary.net:ebyu/13303</identifier><datestamp>2026-10-18T21:13:30Z</datestamp><setSpec>openaire</setSpec><setSpec>driver</setSpec><setSpec>com_ebyu_10000</setSpec><setSpec>col_ebyu_10001</setSpec></header><metadata><oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"><dc:title>Gadolinium-based contrast agents: in vitro paraoxonase 1 inhibition, in silico studies</dc:title><dc:creator>Beydemir, Şükrü</dc:creator><dc:creator>Türkeş, Cüneyt</dc:creator><dc:creator>Yalçın, Ahmet</dc:creator><dc:subject>chromatography</dc:subject><dc:subject>gadolinium-based contrast agents</dc:subject><dc:subject>HDL</dc:subject><dc:subject>inhibition</dc:subject><dc:subject>molecular docking</dc:subject><dc:subject>Paraoxonase</dc:subject><dc:subject>Aryldialkylphosphatase</dc:subject><dc:subject>Computer Simulation</dc:subject><dc:subject>Contrast Media</dc:subject><dc:subject>Drug Design</dc:subject><dc:subject>Enzyme Inhibitors</dc:subject><dc:subject>Gadolinium DTPA</dc:subject><dc:subject>Humans</dc:subject><dc:subject>Inhibitory Concentration 50</dc:subject><dc:subject>Molecular Docking Simulation</dc:subject><dc:subject>Structure-Activity Relationship</dc:subject><dc:subject>aryldialkylphosphatase 1</dc:subject><dc:subject>contrast medium</dc:subject><dc:subject>gadodiamide</dc:subject><dc:subject>gadolinium</dc:subject><dc:subject>gadopentetic acid</dc:subject><dc:subject>gadoteric acid</dc:subject><dc:subject>gadoxetic acid</dc:subject><dc:subject>unclassified drug</dc:subject><dc:subject>enzyme inhibitor</dc:subject><dc:subject>gadolinium pentetate</dc:subject><dc:subject>PON1 protein, human</dc:subject><dc:subject>Article</dc:subject><dc:subject>binding site</dc:subject><dc:subject>competitive inhibition</dc:subject><dc:description>Medications show their biological effects by interaction with enzymes, which have been known to play an essential role in the pathogenesis of many diseases. Inhibition or induction of drug metabolizing enzymes has an essential place in the drug design for many kinds of diseases including cardiovascular, neurological, metabolic, and cancer. The main goal of the current study is to contribute to this growing drug design field by observing PON1–drug interactions. In recent years, the safety of gadolinium-based contrast agents (GBCAs) used in magnetic resonance imaging (MRI) has discussed. In the present study, paraoxonase 1 (PON1) enzyme was purified from human serum by simple chromatographic methods with 4095.24 EU mg−1 protein specific activity. The inhibitory activities of gadoteric acid, gadopentetic acid, gadoxetate disodium, and gadodiamide were investigated on PON1 activity of the enzyme. IC50 values were found in the range of 51.28 ± 0.14 to 285.80 ± 0.96 mM. Ki constants were found as 67.95 ± 0.60 mM, 104.97 ± 0.96 mM, 202.33 ± 1.75 mM, and 299.43 ± 2.64 mM for gadoteric acid, gadopentetic acid, gadoxetate disodium, and gadodiamide, respectively. While the inhibition types are determined as competitive of gadoxetate disodium and gadodiamide by the Lineweaver–Burk curves, it was noncompetitive for other compounds. In addition, the molecular docking analyses of gadoxetate disodium and gadodiamide were carried out to understand the binding interactions on the active site of the PON1 enzyme. The structure–activity relationship (SAR) of the drugs was established on the basis of different substituents and their positions in the compounds. © 2019 Informa UK Limited, trading as Taylor &amp; Francis Group.</dc:description><dc:publisher>Taylor and Francis Ltd.</dc:publisher><dc:date>2021</dc:date><dc:type>Article</dc:type><dc:identifier>https://rdlopen.rawdatalibrary.net/r/ebyu/13303</dc:identifier><dc:identifier>https://doi.org/10.1080/01480545.2019.1620266</dc:identifier><dc:identifier>0148-0545</dc:identifier><dc:language>en</dc:language><dc:relation>Drug and Chemical Toxicology</dc:relation><dc:rights>info:eu-repo/semantics/openAccess</dc:rights><dc:type>info:eu-repo/semantics/article</dc:type><dc:identifier>https://ebyu-rdlopen.rawdatalibrary.net/tr/items/ebyu/13303</dc:identifier></oai_dc:dc></metadata></record></GetRecord></OAI-PMH>