Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET

User menu

  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
Drug Metabolism & Disposition
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET
  • My alerts
  • Log in
  • My Cart
Drug Metabolism & Disposition

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Visit dmd on Facebook
  • Follow dmd on Twitter
  • Follow ASPET on LinkedIn
Research ArticleArticle

DETECTION OF A NOVEL REACTIVE METABOLITE OF DICLOFENAC: EVIDENCE FOR CYP2C9-MEDIATED BIOACTIVATION VIA ARENE OXIDES

Zhengyin Yan, Jian Li, Norman Huebert, Gary W. Caldwell, Yanming Du and Hua Zhong
Drug Metabolism and Disposition June 2005, 33 (6) 706-713; DOI: https://doi.org/10.1124/dmd.104.003095
Zhengyin Yan
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Jian Li
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Norman Huebert
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Gary W. Caldwell
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Yanming Du
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Hua Zhong
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF
Loading

Abstract

A new glutathione adduct (M4) was tentatively identified, likely as 2′-hydroxy-3′-(glutathione-S-yl)-monoclofenac, using liquid chromatography-tandem mass spectrometry analysis of incubations of diclofenac with human liver microsomes. The same conjugate was not detected in incubations with either rat or monkey liver microsomes. Formation of M4 was mediated specifically by CYP2C9 in human liver microsomes, as evidenced by the following observations: 1) cDNA-expressed CYP2C9-catalyzing formation of M4; 2) inhibition of M4 formation by sulfaphenazole, a CYP2C9-selective inhibitor; and 3) strong correlation between the production of M4 and CYP2C9-mediated tolbutamide 4-hydroxylase activities in a panel of human liver microsome samples. Formation of M4 suggests the existence of a new reactive intermediate as diclofenac-2′,3′-oxide. A tentative pathway states that diclofenac is oxidized to diclofenac-2′,3′-oxide that reacts with glutathione (GSH) to form a thioether conjugate at the C-3′ position, followed by a concomitant loss of chlorine to give rise to M4. Furthermore, a likely mechanism leading to the formation of diclofenac oxides is rationalized: CYP2C9-catalyzed oxidation at the C-3′ position of the dichlorophenyl ring to form a cationic σ-complex that subsequently results in diclofenac-3′,4′-oxide and diclofenac-2′,3′-oxide; the former oxide is converted to 4′-hydroxy-diclofenac as a major metabolite and can be trapped by GSH to produce 4′-hydroxy-3′-glutathione-S-yl diclofenac (M2), whereas the latter oxide forms 3′-hydroxy-diclofenac and can be trapped by GSH to produce M4. This mechanism is consistent with the structural modeling of the CYP2C9-diclofenac complex, which reveals that both the C-3′ and C-4′ of the dichlorophenyl ring are proximate to the heme group.

Footnotes

  • Article, publication date, and citation information can be found at http://dmd.aspetjournals.org.

  • doi:10.1124/dmd.104.003095.

  • ABBREVIATIONS: P450, cytochrome P450; GSX, isotope-labeled glutathione; GSH, glutathione; LC, liquid chromatography; HLM, human liver microsome; MS, mass spectrometry; MS/MS, tandem MS; CID, collision-induced dissociation.

    • Received November 22, 2004.
    • Accepted March 3, 2005.
  • The American Society for Pharmacology and Experimental Therapeutics
View Full Text

 

DMD articles become freely available 12 months after publication, and remain freely available for 5 years. 

Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page. 

 

  • Click here for information on institutional subscriptions.
  • Click here for information on individual ASPET membership.

 

Log in using your username and password

Forgot your user name or password?

Purchase access

You may purchase access to this article. This will require you to create an account if you don't already have one.
PreviousNext
Back to top

In this issue

Drug Metabolism and Disposition: 33 (6)
Drug Metabolism and Disposition
Vol. 33, Issue 6
1 Jun 2005
  • Table of Contents
  • About the Cover
  • Index by author
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Drug Metabolism & Disposition article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
DETECTION OF A NOVEL REACTIVE METABOLITE OF DICLOFENAC: EVIDENCE FOR CYP2C9-MEDIATED BIOACTIVATION VIA ARENE OXIDES
(Your Name) has forwarded a page to you from Drug Metabolism & Disposition
(Your Name) thought you would be interested in this article in Drug Metabolism & Disposition.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Research ArticleArticle

DETECTION OF A NOVEL REACTIVE METABOLITE OF DICLOFENAC: EVIDENCE FOR CYP2C9-MEDIATED BIOACTIVATION VIA ARENE OXIDES

Zhengyin Yan, Jian Li, Norman Huebert, Gary W. Caldwell, Yanming Du and Hua Zhong
Drug Metabolism and Disposition June 1, 2005, 33 (6) 706-713; DOI: https://doi.org/10.1124/dmd.104.003095

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Research ArticleArticle

DETECTION OF A NOVEL REACTIVE METABOLITE OF DICLOFENAC: EVIDENCE FOR CYP2C9-MEDIATED BIOACTIVATION VIA ARENE OXIDES

Zhengyin Yan, Jian Li, Norman Huebert, Gary W. Caldwell, Yanming Du and Hua Zhong
Drug Metabolism and Disposition June 1, 2005, 33 (6) 706-713; DOI: https://doi.org/10.1124/dmd.104.003095
Reddit logo Twitter logo Facebook logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Materials and Methods
    • Results
    • Discussion
    • Footnotes
    • References
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF

Related Articles

Cited By...

More in this TOC Section

  • A PBPK model for CBD in adults and children
  • Olanzapine Glucuronidation in Humanized Mice
  • rs2242480 Regulates the Expression of CYP3A4 and CYP3A5
Show more Articles

Similar Articles

Advertisement
  • Home
  • Alerts
Facebook   Twitter   LinkedIn   RSS

Navigate

  • Current Issue
  • Fast Forward by date
  • Fast Forward by section
  • Latest Articles
  • Archive
  • Search for Articles
  • Feedback
  • ASPET

More Information

  • About DMD
  • Editorial Board
  • Instructions to Authors
  • Submit a Manuscript
  • Customized Alerts
  • RSS Feeds
  • Subscriptions
  • Permissions
  • Terms & Conditions of Use

ASPET's Other Journals

  • Journal of Pharmacology and Experimental Therapeutics
  • Molecular Pharmacology
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-009X (Online)

Copyright © 2023 by the American Society for Pharmacology and Experimental Therapeutics