Home | About PM | Editorial board | Search | Ahead of print | Current Issue | Archives | Instructions | Subscribe | Advertise | Contact us |  Login 
Pharmacognosy Magazine
Search Article 
  
Advanced search 
 
ORIGINAL ARTICLE
Year : 2017  |  Volume : 13  |  Issue : 52  |  Page : 895-899

Studying the Inhibitory Effect of Quercetin and Thymoquinone on Human Cytochrome P450 Enzyme Activities


1 School of Pharmacy, Pacific University, Oregon, USA
2 College of Pharmacy, Kafr ElSheikh University, Kafr El Sheikh Governorate, Egypt

Correspondence Address:
Fawzy Elbarbry
Pacific University School of Pharmacy, 222 SE 8th Ave., Hillsboro, OR 97123,
USA
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-1296.224342

Rights and Permissions

Background: Quercetin (QR) and thymoquinone (TQ) are herbal remedies that are currently extensively used by the general population to prevent and treat various chronic conditions. Therefore, investigating the potential of pharmacokinetic interactions caused by the concomitant use of these herbal remedies and conventional medicine is warranted to ensure patient safety. Purpose of the Study: This study was conducted to determine the inhibitory effect of QR and TQ, two commonly used remedies, on the activities of selected cytochrome P450 (CYP) enzymes that play an important role in drug metabolism and/or toxicology. Materials and Methods: The in vitro studies were conducted using fluorescence-based high throughput assays using human c-DNA baculovirus expressed CYP enzymes. For measuring CYP2E1 activity, a validated High-performance liquid chromatography (HPLC) assay was utilized to measure the formation of 6-hydroxychlorzoxazone. Results: The obtained half-maximum inhibitory concentration values with known positive control inhibitors of this study were comparable to the published values indicating accurate experimental techniques. Although QR did not show any significant effect on CYP1A2 and CYP2E1, it exhibited a strong inhibitory effect against CYP2D6 and a moderate effect against CYP2C19 and CYP3A4. On the other hand, TQ demonstrated a strong and a moderate inhibitory effect against CYP3A4 and CYP2C19, respectively. Conclusions: The findings of this study may indicate that consumption of QR or TQ, in the form of food or dietary supplements, with drugs that are metabolized by CYP2C19, CYP2D6, or CYP3A4 may cause significant herb-drug interactions. Abbreviations used: ABT: Aminobenztriazole, BZF: 7,8 Benzoflavone, CYP: Cytochrome P450, GB: Gingko Biloba, IC50: Half-maximum inhibitory concentration, KTZ: Ketoconazole, QND: Quinidine, QR: Quercetin, TCP: Tranylcypromine, TQ: Thymoquinone.


[FULL TEXT] [PDF]*
Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed850    
    Printed26    
    Emailed0    
    PDF Downloaded25    
    Comments [Add]    

Recommend this journal