Development and application of a comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry method for the analysis of L-beta-methylamino-alanine in human tissue.

L-Beta-methylamino-alanine (BMAA) has been proposed as a worldwide contributor to neurodegenerative diseases, including Parkinson dementia complex (PDC) of Guam and Alzheimer's disease (AD). Recent conflicting reports of the presence of this amino acid in human brain from patients affected by these diseases have made it necessary to develop methods that provide unambiguous detection in complex samples. Comprehensive two-dimensional gas chromatography coupled with time-of-flight-mass-spectrometry analysis (GCxGC-TOFMS) followed by a targeted Parallel Factor Analysis (PARAFAC) deconvolution method has been used recently in metabolomic investigations to separate, identify, and quantify components of complex biological specimens. We have extended and applied this methodology to the toxicological problem of detecting BMAA in extracts of brain tissue. Our results show that BMAA can be isolated from closely eluting compounds and detected in trace amounts in extracts of brain tissue spiked with low levels of this analyte, ranging from 2.5ppb to 50ppb, with a limit of detection (LOD) of 0.7ppb. This new method was sufficiently sensitive to detect BMAA in cerebral extracts of mice fed BMAA. This optimized approach was then applied to analyze tissue from humans; however, no BMAA was detected in the brain extracts from controls or patients with PDC or AD. Our results demonstrate the application of multidimensional chromatography-mass spectrometry methods and computational deconvolution analysis to the problem of detecting trace amounts of a potential toxin in brain extracts from mice and humans.

[1]  U. Brinkman,et al.  Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection applied to the determination of pesticides in food extracts. , 2002, Journal of chromatography. A.

[2]  P. Marriott,et al.  Characterisation of lavender essential oils by using gas chromatography-mass spectrometry with correlation of linear retention indices and comparison with comprehensive two-dimensional gas chromatography. , 2002, Journal of chromatography. A.

[3]  M. Lidstrom,et al.  Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection: analysis of amino acid and organic acid trimethylsilyl derivatives, with application to the analysis of metabolites in rye grass samples. , 2005, Talanta.

[4]  John B. Phillips,et al.  Comprehensive Two-Dimensional Gas Chromatography using an On-Column Thermal Modulator Interface , 1991 .

[5]  J. Seeley,et al.  Comprehensive two-dimensional gas chromatography via differential flow modulation , 2000, Analytical chemistry.

[6]  W. Bradley,et al.  Cyanobacteria and BMAA exposure from desert dust: A possible link to sporadic ALS among Gulf War veterans , 2009, Amyotrophic lateral sclerosis : official publication of the World Federation of Neurology Research Group on Motor Neuron Diseases.

[7]  Jamin C. Hoggard,et al.  Comprehensive analysis of yeast metabolite GC x GC-TOFMS data: combining discovery-mode and deconvolution chemometric software. , 2007, The Analyst.

[8]  Paul Alan Cox,et al.  A mechanism for slow release of biomagnified cyanobacterial neurotoxins and neurodegenerative disease in Guam. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[9]  M. Lidstrom,et al.  Liquid chromatography-tandem quadrupole mass spectrometry and comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry measurement of targeted metabolites of Methylobacterium extorquens AM1 grown on two different carbon sources. , 2009, Journal of chromatography. A.

[10]  Jamin C. Hoggard,et al.  Identification and evaluation of cycling yeast metabolites in two-dimensional comprehensive gas chromatography-time-of-flight-mass spectrometry data. , 2008, Journal of chromatography. A.

[11]  J. Hardy,et al.  Genome-wide analysis of the parkinsonism-dementia complex of Guam. , 2004, Archives of neurology.

[12]  Sanford P. Markey,et al.  2‐Amino‐3‐(methylamino)‐propanoic acid (BMAA) in cycad flour , 1990, Neurology.

[13]  R. Synovec,et al.  Trends in chemometric analysis of comprehensive two-dimensional separations , 2004, Analytical and bioanalytical chemistry.

[14]  Jamin C. Hoggard,et al.  Time-dependent profiling of metabolites from Snf1 mutant and wild type yeast cells. , 2008, Analytical chemistry.

[15]  Mohamed Adahchour,et al.  Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection for the trace analysis of flavour compounds in food. , 2003, Journal of chromatography. A.

[16]  Robert E. Synovec,et al.  Comprehensive Two-Dimensional High-Speed Gas Chromatography with Chemometric Analysis , 1998 .

[17]  U. Brinkman,et al.  Simple, non-moving modulation interface for comprehensive two-dimensional gas chromatography. , 2001, Journal of chromatography. A.

[18]  P. Nunn,et al.  The preparation of l- and d-α-amino-β-methylaminopropionic acids and the identification of the compound isolated from Cycas circinalis as the l-isomer , 1968 .

[19]  D. Galasko,et al.  ALS and PDC of Guam: Forty-year follow-up , 2002, Neurology.

[20]  C. Shaw,et al.  Chronic Exposure to Dietary Sterol Glucosides is Neurotoxic to Motor Neurons and Induces an ALS–PDC Phenotype , 2008, NeuroMolecular Medicine.

[21]  R. Speth,et al.  Animal models of BMAA neurotoxicity: a critical review. , 2008, Life sciences.

[22]  T. Montine,et al.  Parkinson-dementia complex and development of a new stable isotope dilution assay for BMAA detection in tissue. , 2009, Toxicology and applied pharmacology.

[23]  P. Marriott,et al.  Comprehensive two-dimensional gas chromatography using a modulating cryogenic trap , 1998 .

[24]  Jamin C. Hoggard,et al.  Parallel factor analysis (PARAFAC) of target analytes in GC x GC-TOFMS data: automated selection of a model with an appropriate number of factors. , 2007, Analytical chemistry.

[25]  A. Vega,et al.  α-Amino-β-methylaminopropionic acid, a new amino acid from seeds of Cycas circinalis , 1967 .

[26]  D. Mash,et al.  Cyanobacterial neurotoxin BMAA in ALS and Alzheimer’s disease , 2009, Acta neurologica Scandinavica.

[27]  M. Duncan.  Role of the cycad neurotoxin BMAA in the amyotrophic lateral sclerosis-parkinsonism dementia complex of the western Pacific. , 1991, Advances in neurology.

[28]  T. Krüger,et al.  LC-MS/MS determination of the isomeric neurotoxins BMAA (beta-N-methylamino-L-alanine) and DAB (2,4-diaminobutyric acid) in cyanobacteria and seeds of Cycas revoluta and Lathyrus latifolius. , 2010, Toxicon : official journal of the International Society on Toxinology.

[29]  Paul Alan Cox,et al.  Cycad neurotoxins, consumption of flying foxes, and ALS-PDC disease in Guam. , 2002, Neurology.

[30]  R. Bidigare,et al.  Diverse taxa of cyanobacteria produce beta-N-methylamino-L-alanine, a neurotoxic amino acid. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[31]  J. Bergquist,et al.  Beta-Methylamino-L-Alanine Analysis by Liquid Chromatography Tandem Mass Spectrometry with iTRAQ as the Derivative , 2009, European journal of mass spectrometry.

[32]  R. Cruz-Aguado,et al.  Lack of behavioral and neuropathological effects of dietary β-methylamino-l-alanine (BMAA) in mice , 2006, Pharmacology Biochemistry and Behavior.

[33]  G. Schellenberg,et al.  Clinical features and changing patterns of neurodegenerative disorders on Guam, 1997–2000 , 2002, Neurology.

[34]  K. Hellenäs,et al.  Determination of the neurotoxin BMAA (beta-N-methylamino-L-alanine) in cycad seed and cyanobacteria by LC-MS/MS (liquid chromatography tandem mass spectrometry). , 2008, The Analyst.

[35]  Jean P O'Malley,et al.  Selective vulnerability of preterm white matter to oxidative damage defined by F2‐isoprostanes , 2005, Annals of neurology.

[36]  Jamin C. Hoggard,et al.  Automated resolution of nontarget analyte signals in GC x GC-TOFMS data using parallel factor analysis. , 2008, Analytical chemistry.

[37]  D. Williams,et al.  Isolation of various forms of sterol β‐d‐glucoside from the seed of Cycas circinalis: neurotoxicity and implications for ALS‐parkinsonism dementia complex , 2002, Journal of neurochemistry.