Document Detail


A rapid oxygen exchange on prostaglandins in plasma represents plasma esterase activity that is inhibited by diethylumbelliferyl phosphate with high affinity.
MedLine Citation:
PMID:  22976214     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
RATIONALE: Fatty acids (FA) labeled with (18) O at the carboxyl group, including oxidized species (FA(18) O), are a useful, low-cost, and easy to prepare tool for quantitative and qualitative mass spectrometry (MS) analysis in biological systems. In addition, they are used to trace the fate of FAs in metabolic pathways including FA re-esterification and lipid remodeling pathways. Although a rapid (18) O exchange on FA(18) O in biological systems has been reported, the mechanism contributing to (18) O exchange has not been fully evaluated. This gap in knowledge limits the use of FA(18) O as a standard for MS and complicates data interpretation for FA metabolism in biological systems.
METHODS: In the present study we have addressed a number of possible mechanisms for a rapid (18) O exchange on prostaglandin E(2) (PGE(2) ) using rat plasma as a model. High-performance liquid chromatography coupled with electrospray ionization triple quadrupole MS in the multiple reaction monitoring mode was used for quantification.
RESULTS: The major mechanism for a rapid (18) O exchange on PGE(2) (18) O in rat plasma is PGE(2) processing with esterases, while FA re-esterification and non-enzymatic mechanisms do not significantly contribute to this phenomenon. In addition, we report a highly effective inhibition of (18) O exchange with diethylumbelliferyl phosphate that can be used to stabilize FA(18) O in biological samples.
CONCLUSIONS: These data indicate the necessity to consider esterase activity when FA(18) O are used to study FA metabolism, and the importance of esterase activity inhibition when FA(18) O are used as internal standards for MS analysis in biological systems. In addition, the results provide a rational for the development of new approaches to study esterase activities and affinity towards modified FA.
Authors:
Stephen A Brose; Mikhail Y Golovko
Related Documents :
22593694 - Phenolic compounds analysis of root, stalk, and leaves of nettle.
22589114 - Ionic liquid-based dispersive liquid-liquid microextraction with back-extraction couple...
18597314 - Characterization of a pilot plant airlift tower loop bioreactor: ii. evaluation of glob...
7161374 - Determination of cellular fatty acid compositions of various yeasts by gas-liquid chrom...
23216124 - Development and validation of an ultra-sensitive method for the measurement of plasma r...
21175364 - Determination of free and deconjugated testosterone and epitestosterone in urine using ...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural    
Journal Detail:
Title:  Rapid communications in mass spectrometry : RCM     Volume:  26     ISSN:  1097-0231     ISO Abbreviation:  Rapid Commun. Mass Spectrom.     Publication Date:  2012 Oct 
Date Detail:
Created Date:  2012-09-14     Completed Date:  2013-02-05     Revised Date:  2013-04-16    
Medline Journal Info:
Nlm Unique ID:  8802365     Medline TA:  Rapid Commun Mass Spectrom     Country:  England    
Other Details:
Languages:  eng     Pagination:  2472-6     Citation Subset:  IM    
Copyright Information:
Copyright © 2012 John Wiley & Sons, Ltd.
Affiliation:
Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota, Grand Forks, ND 58202-9037, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Chromatography, High Pressure Liquid
Dinoprostone / blood*,  metabolism*
Esterases / antagonists & inhibitors*,  metabolism
Fatty Acids / metabolism
Organophosphorus Compounds / pharmacology*
Oxygen / metabolism*
Plasma / enzymology*
Rats
Rats, Sprague-Dawley
Spectrometry, Mass, Electrospray Ionization
Umbelliferones / pharmacology*
Grant Support
ID/Acronym/Agency:
5P20RR017699/RR/NCRR NIH HHS; 5R21NS064480-02/NS/NINDS NIH HHS; P20 RR017699/RR/NCRR NIH HHS; R21 NS064480/NS/NINDS NIH HHS
Chemical
Reg. No./Substance:
0/Fatty Acids; 0/Organophosphorus Compounds; 0/Umbelliferones; 363-24-6/Dinoprostone; 7782-44-7/Oxygen; 897-83-6/diethylumbelliferyl phosphate; EC 3.1.-/Esterases

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


Previous Document:  Substructure-based annotation of high-resolution multistage MS(n) spectral trees.
Next Document:  Direct mass spectrometric screening of antibiotics from bacterial surfaces using liquid extraction s...