Detection of dihydroxycholesterols in human plasma using HPLC-ESI-MS/MS.
Ratna Karuna, Isabelle Christen, Andreas W Sailer, Francis Bitsch, Juan Zhang
Index: Steroids 99 , 131-8, (2015)
Full Text: HTML
Abstract
We report a straightforward sample preparation procedure and a direct liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method for the analysis of 7alpha,25-dihydroxycholesterol (7α25-OHC) and 7alpha,27-dihydroxycholesterol (7α27-OHC). By applying a slow protein precipitation approach using cold ethanol, we were able to detect and quantify 7α25-OHC and 7α27-OHC in a fast and reliable manner. The average concentrations from 20 healthy individuals were determined to be 0.21±0.05nM for 7α25-OHC and 3.4±0.1nM for 7α27-OHC. In addition, we are the first to report the average degrees of esterification (n=8) to be 73.8% and 82% for 7α25-OHC and 7α27-OHC, respectively. Using the established method, we achieved the sensitivity sufficient for detecting low abundant dihydroxylated oxysterols in healthy individuals. This result should enable extension of these studies towards a comprehensive analysis of oxysterol levels under disease conditions. Copyright © 2015 Elsevier Inc. All rights reserved.
Related Compounds
Related Articles:
BBS4 directly affects proliferation and differentiation of adipocytes.
2014-09-01
[Cell. Mol. Life Sci. 71(17) , 3381-92, (2014)]
2014-09-26
[J. Chromatogr. A. 1361 , 265-76, (2014)]
2014-11-01
[J. Am. Soc. Mass Spectrom. 25(11) , 1897-907, (2014)]
2014-10-01
[Eur. J. Pharm. Biopharm. 88(2) , 406-14, (2014)]
2014-01-01
[PLoS ONE 9(10) , e109201, (2014)]