| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Received on December 20, 2004
Accepted on May 6, 2005
Automation and Analytical Techniques |
1 Laboratory of Pediatrics and Neurology (424), Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
2 Metabolic Unit, Department of Clinical Chemistry, VU University Medical Centre Amsterdam, Amsterdam, The Netherlands
3 Departments of Endocrinology (531) and Epidemiology and Biostatistics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
* To whom correspondence should be addressed. E-mail: h.blom{at}cukz.umcn.nl.
Background: It has been postulated that changes in S-adenosylhomocysteine (AdoHcy), a potent inhibitor of transmethylation, provide a mechanism by which increased homocysteine causes its detrimental effects. We aimed to develop a rapid and sensitive method to measure AdoHcy and its precursor S-adenosylmethionine (AdoMet).
Methods: We used stable-isotope dilution liquid chromatography-electrospray injection tandem mass spectrometry (LC-ESI-MS/MS) to measure AdoMet and AdoHcy in plasma. Acetic acid was added to prevent AdoMet degradation. Solid-phase extraction (SPE) columns containing phenylboronic acid were used to bind AdoMet, AdoHcy, and their internal standards and for sample cleanup. An HPLC C18 column directly coupled to the LC-MS/MS was used for separation and detection.
Results: In plasma samples, the interassay CVs for AdoMet and AdoHcy were 3.9% and 8.3%, and the intraassay CVs were 4.2% and 6.7%, respectively. Mean recoveries were 94.5% for AdoMet and 96.8% for AdoHcy. The quantification limits were 2.0 and 1.0 nmol/L for AdoMet and AdoHcy, respectively. Immediate acidification of the plasma samples with acetic acid prevented the observed AdoMet degradation. In a group of controls (mean plasma total Hcy, 11.2 µmol/L), plasma AdoMet and AdoHcy were 94.5 and 12.3 nmol/L, respectively.
Conclusions: Stable-isotope dilution LC-ESI-MS/MS allows sensitive and rapid measurement of AdoMet and AdoHcy. The SPE columns enable simple cleanup, and no metabolite derivatization is needed. The instability of AdoMet is a serious problem and can be prevented easily by immediate acidification of samples.
The following articles in journals at HighWire Press have cited this article:
|
|
 |
|
  R. Obeid, A. Schadt, U. Dillmann, P. Kostopoulos, K. Fassbender, and W. Herrmann Methylation Status and Neurodegenerative Markers in Parkinson Disease Clin. Chem., October 1, 2009; 55(10): 1852 - 1860. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Malanovic, I. Streith, H. Wolinski, G. Rechberger, S. D. Kohlwein, and O. Tehlivets S-Adenosyl-L-homocysteine Hydrolase, Key Enzyme of Methylation Metabolism, Regulates Phosphatidylcholine Synthesis and Triacylglycerol Homeostasis in Yeast: IMPLICATIONS FOR HOMOCYSTEINE AS A RISK FACTOR OF ATHEROSCLEROSIS J. Biol. Chem., August 29, 2008; 283(35): 23989 - 23999. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. -G. Debray, Y. Boulanger, A. Khiat, J. -C. Decarie, J. Orquin, M. -S. Roy, A. Lortie, F. Ramos, N. M. Verhoeven, E. Struys, et al. Reduced brain choline in homocystinuria due to remethylation defects Neurology, July 1, 2008; 71(1): 44 - 49. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Wagner and M. J Koury S-Adenosylhomocysteine a better indicator of vascular disease than homocysteine? Am. J. Clinical Nutrition, December 1, 2007; 86(6): 1581 - 1585. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
U. Hubner, H. Schorr, R. Eckert, J. Geisel, and W. Herrmann Stability of Plasma Homocysteine, S-Adenosylmethionine, and S-Adenosylhomocysteine in EDTA, Acidic Citrate, and PrimavetteTM Collection Tubes Clin. Chem., December 1, 2007; 53(12): 2217 - 2218. [Full Text] [PDF]
|
|
|
|
|
|
R. Obeid, M. Kasoha, J.-P. Knapp, P. Kostopoulos, G. Becker, K. Fassbender, and W. Herrmann Folate and Methylation Status in Relation to Phosphorylated Tau Protein(181P) and {beta}-Amyloid(1-42) in Cerebrospinal Fluid Clin. Chem., June 1, 2007; 53(6): 1129 - 1136. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Obeid, P. Kostopoulos, J.-P. Knapp, M. Kasoha, G. Becker, K. Fassbender, and W. Herrmann Biomarkers of Folate and Vitamin B12 Are Related in Blood and Cerebrospinal Fluid Clin. Chem., February 1, 2007; 53(2): 326 - 333. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C.-W. Hu, C.-J. Wang, L. W. Chang, and M.-R. Chao Clinical-Scale High-Throughput Analysis of Urinary 8-Oxo-7,8-Dihydro-2'-Deoxyguanosine by Isotope-Dilution Liquid Chromatography-Tandem Mass Spectrometry with On-Line Solid-Phase Extraction Clin. Chem., July 1, 2006; 52(7): 1381 - 1388. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
