Next Article in Journal
Separation Technique for the Determination of Highly Polar Metabolites in Biological Samples
Next Article in Special Issue
Polyamines under Abiotic Stress: Metabolic Crossroads and Hormonal Crosstalks in Plants
Previous Article in Journal
Development of Metabolic Indicators of Burn Injury: Very Low Density Lipoprotein (VLDL) and Acetoacetate Are Highly Correlated to Severity of Burn Injury in Rats
Previous Article in Special Issue
5-Aminoimidazole-4-carboxamide-1-beta-D-ribofuranosyl 5'-Monophosphate (AICAR), a Highly Conserved Purine Intermediate with Multiple Effects
Metabolites 2012, 2(3), 479-495; doi:10.3390/metabo2030479

1H Nuclear Magnetic Resonance (NMR) Metabolomic Study of Chronic Organophosphate Exposure in Rats

1,* , 2,†
2 and 2
1 Department of Electronic and Nanostructured Materials, Sandia National Laboratories, Albuquerque, NM 87185, USA 2 Department of Biochemistry and Molecular Biology, School of Medicine, University of Texas Medical Branch, Galveston, TX, 77555, USA 3 Energetics Characterization Department, Sandia National Laboratories, Albuquerque, NM 87185, USA 4 Institute for Molecular Medicine for the Prevention of Human Diseases, Centers for Proteomics & System Biology, University of Texas Health Science Center Houston, 1825 Pressler, Houston, TX 77555, USA 5 Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA Present address: Center of Cellular Molecular Platforms, National Center for Biological Sciences, GKVK, Bellary Road, Bangalore -65, India
* Author to whom correspondence should be addressed.
Received: 18 April 2012 / Revised: 26 June 2012 / Accepted: 5 July 2012 / Published: 24 July 2012
(This article belongs to the Special Issue Feature Papers)
View Full-Text   |   Download PDF [769 KB, uploaded 24 July 2012]   |  


1H NMR spectroscopy and chemometric analysis were used to characterize rat urine obtained after chronic exposure to either tributyl phosphate (TBP) or triphenyl phosphate (TPP). In this study, the daily dose exposure was 1.5 mg/kg body weight for TBP, or 2.0 mg/kg body weight for TPP, administered over a 15-week period. Orthogonal signal correction (OSC) -filtered partial least square discriminant analysis (OSC-PLSDA) was used to predict and classify exposure to these organophosphates. During the development of the model, the classification error was evaluated as a function of the number of latent variables. NMR spectral regions and corresponding metabolites important for determination of exposure type were identified using variable importance in projection (VIP) coefficients obtained from the OSC-PLSDA analysis. As expected, the model for classification of chronic (1.5–2.0 mg/kg body weight daily) TBP or TPP exposure was not as strong as the previously reported model developed for identifying acute (15–20 mg/kg body weight) exposure. The set of majorly impacted metabolites identified for chronic TBP or TPP exposure was slightly different than those metabolites previously identified for acute exposure. These metabolites were then mapped to different metabolite pathways and ranked, allowing the metabolic response to chronic organophosphate exposure to be addressed.
Keywords: NMR; metabolomics; tributyl phosphate, triphenyl phosphate, chemometrics NMR; metabolomics; tributyl phosphate, triphenyl phosphate, chemometrics
This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Supplementary material


Share & Cite This Article

Further Mendeley | CiteULike
Export to BibTeX |
EndNote |
MDPI and ACS Style

Alam, T.M.; Neerathilingam, M.; Alam, M.K.; Volk, D.E.; Ansari, G.A.S.; Sarkar, S.; Luxon, B.A. 1H Nuclear Magnetic Resonance (NMR) Metabolomic Study of Chronic Organophosphate Exposure in Rats. Metabolites 2012, 2, 479-495.

View more citation formats

Related Articles

Article Metrics

For more information on the journal, click here


[Return to top]
Metabolites EISSN 2218-1989 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert