Document Detail

Effect of St. John's wort on free radical production.
MedLine Citation:
PMID:  11441908     Owner:  NLM     Status:  MEDLINE    
St. John's wort (Hypericum perforatum) is an herbal compound used in the treatment of burns, bruises, swelling, anxiety, and most recently, mild to moderate depression. The present study was designed to evaluate the antioxidant properties of St. John's wort in both cell-free and human vascular tissue. The experiment was performed initially in a cell-free system using Krebs buffer and a combination of xanthine/xanthine oxidase to initiate the production of the superoxide radical. Additionally, human placental vein was incubated in Krebs buffer without xanthine or xanthine oxidase to study the effects of St. John's wort on human tissue in vitro. Commercially available formulations of St. John's wort, standardized to either hypericin or hyperforin, were dissolved in an alkaline solution, and the following dilutions were made: 1:1, 1:2.5, 1:5, 1:7.5, 1:10, and 1:20. Lucigenin chemiluminescence was used to measure free radical production in both systems. A pro-oxidant effect was seen at the highest concentration, 1:1. Lower concentrations revealed antioxidant properties of the compound. All dilutions below 1:1 in both systems showed a dose-related inverse relationship of superoxide inhibition. The largest suppression was seen at the most dilute concentration, 1:20. The addition of 10(-3) M tiron inhibited the chemiluminescence signal, thereby confirming the production of superoxide. The results of this study suggest that St. John's wort inhibits free radical production in both cell-free and human vascular tissue.
E J Hunt; C E Lester; E A Lester; R L Tackett
Related Documents :
14870858 - Microwaves in drug discovery and multi-step synthesis.
20347528 - Hydrogen as a novel and effective treatment of acute carbon monoxide poisoning.
20443568 - Epr studies of o(2)(*-), oh, and (1)o(2) scavenging and prevention of glutathione deple...
18642758 - Does selenium exert cardioprotective effects against oxidative stress in myocardial isc...
18584068 - Improved synthesis of dcdhf fluorophores with maleimide functional groups.
20715868 - Oxidation reactions mediated by single-walled carbon nanotubes in aqueous solution.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Life sciences     Volume:  69     ISSN:  0024-3205     ISO Abbreviation:  Life Sci.     Publication Date:  2001 Jun 
Date Detail:
Created Date:  2001-07-09     Completed Date:  2001-07-26     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0375521     Medline TA:  Life Sci     Country:  England    
Other Details:
Languages:  eng     Pagination:  181-90     Citation Subset:  IM    
University of Georgia College of Pharmacy, Department of Clinical and Administrative Sciences, Athens 30602, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt / metabolism
Antioxidants / chemistry,  pharmacology*
Bicyclo Compounds
Cell-Free System
Dose-Response Relationship, Drug
Enzyme Inhibitors / chemistry,  pharmacology
Free Radicals / metabolism
Hypericum* / chemistry
Indicators and Reagents / metabolism
Perylene / analogs & derivatives*,  chemistry,  pharmacology
Phloroglucinol / analogs & derivatives
Placenta / blood supply
Plant Extracts / pharmacology*
Plants, Medicinal*
Superoxides / metabolism*
Terpenes / chemistry,  pharmacology
Veins / drug effects,  metabolism*
Reg. No./Substance:
0/Antioxidants; 0/Bicyclo Compounds; 0/Enzyme Inhibitors; 0/Free Radicals; 0/Indicators and Reagents; 0/Plant Extracts; 0/Terpenes; 108-73-6/Phloroglucinol; 11062-77-4/Superoxides; 11079-53-1/hyperforin; 149-45-1/1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt; 198-55-0/Perylene; 548-04-9/hypericin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Human urotensin II increases coronary perfusion pressure in the isolated rat heart: potentiation by ...
Next Document:  Effect of cyclosporine, a P-glycoprotein inhibitor, on the pharmacokinetics of cefepime in rat blood...