NMR and Mass Spectrometry approaches to metabolomics in man and mouse Dr. Julian Griffin jlg40@mole.bio.cam.ac.uk Dept of Biochemistry, University of Cambridge Overview What is metabolomics and why do we need it? Type II diabetes CAD and cardiovascular disease Man, mouse and rat Markers of drug efficacy Type I diabetes Biomarker discovery The basis of metabolomics Metabolomics/metabonomics the quantitative measurement of metabolic responses to pathophysiological stimuli or genetic modification Measure small molecule concentrations through a global approach NMR spectroscopy Mass Spectrometry Use pattern recognition to define metabolism in a multidimensional space metabolic phenotype metabotype Type II diabetes Class 1 dbdb-0-4.24_ex_glucose_2.M1 (PCA-X), PCA all t[Comp. 1]/t[Comp. 2] Colored according to classes in M1 1.00 Rat 0.4 0.80 t[2] Metabolism is very easily compared across animal models and back to humans With Roger Cox, Michael Cheeseman and Tertius Hough looked at the effects of age and gender on the profile of diabetic urine Ignored glucose! Identified a number of novel perturbations E.g. NMN and nucleotide metabolism 0.6 PLS Component [2] Class 2 Class 1 Class 2 Class 3 Class 4 0.2 0.60 0.40 -0.0 0.20 -0.2 0.00 Mouse Human -0.20 -0.4 -0.40 -0.6 -0.60 -0.8 -0.80 -0.9 -0.8 -0.80 -0.7 -0.70 -0.6 -0.60 -0.5-0.50-0.4-0.40-0.3 -1.00 -0.90 -0.30 -0.2 -0.20 -0.1 -0.10 0.0 0.00 0.1 0.10 0.2 0.30 0.3 0.400.4 0.500.50.60 0.60.70 0.7 0.20 0.80 0.8 0.90 Beta-alanine metabolism Methane metabolism Nitrogen metabolism TCA cycle & Oxidative phosphorylation Pyrimidine, purine & nicotine/nicotinamide metabolism PCA of 160 urine samples from a diabetic mouse model (dbdb mouse maintained at MRC Harwell). Class 1 – Male Wild Type/Heterozygous; Class 2 - Male Homozygous; Class 3 - Female WT/Heterozygous; Class 4 - Female Homozygous. Ascorbate and aldarate metabolism Benzoate metabolism Amino acid metabolism Glyoxylate metabolism Urea cycle Salek RM, Physiol Genomics 2007 0.9 1.00 PLS Component [1] t[1] Biotin metabolism Styrene degradation pyruvate metabolism & glycolysis/ gluconeogenesis Taurine, bile acid & Sulfur metabolism Propanoate, C5 branched dibasic acid & Butanoate metabolism CAD and cardiovascular disease Predict the occurrence and severity of coronary artery disease using blood serum. Blood sera collected at Papworth hospital as part of trials concerning statins Such systems may produce significant financial savings angiography, currently the gold standard for diagnosis. Brindle JT et al., 2002. Nat Med. 8(12), 1439-45. However, on closer inspection: ‘Biomarkers’ are rather generic Gender and statin treatment effect the same ‘biomarkers’ of disease Groups must be stratified Over fitting of the pattern recognition models is a problem Kirschenlohr et al., Nature Medicine, 2006 Mouse models of atherosclerosis Mice - C57Bl/6, LDLR-/Diet - Control RM1 Diet (SDS), HFCC Diet (Hope Farms) Blood plasma (and urine) Class 2, Control High fat diet Class 2, Control Normal diet (Week 0) Class 1, Control Normal diet Class 4, LDLR-/Normal diet (Week 0) Class 3, LDLR-/Normal diet Class 4, LDLR -/High fat diet Cheng KK, Physiol Genomics, 2010 ANOVA-PCA Source: Analytica Chimica Acta 629 (2008) 47-55 Diet effect RM1 diet RM1 diet HFCC diet HFCC diet ANOVA-PCA Diet + error Genotype effect LDLR -/LDLR -/- B6 B6 ANOVA-PCA Gen + error Variance components (case study) 60 52.65 Variance (%) 50 40 28.50 30 20 11.84 7.01 Gen DxG 10 0 Diet Component Within Discussion & Conclusion Metabolomics can now be used as a high throughput phenotyping tool in mice Metabolism is also very translatable across species Reduced variability in phenotype can simplify biomarker discovery Mass spectrometry is much more sensitive if you know what you are looking for Database tools are also in place to conduct this across multiple sites Acknowledgements JLG Group (present) Zsuszi Ament Michael Baker Cecilia Castro Martin Coleston Sue Connor Melanie Gulston Cheng Kian Kai Steve Murphitt Lee Roberts Reza Salek Ben Tucker Baljit Ubhi Xinzhu Wang James West Collaborators Roger Cox, Michael Cheeseman & Tertius Hough, MRC Harwell Anne Cooke & Paola Zaccone Andy Nicholls & John Haselden, GSK Funders: BBSRC, EU, BHF, GlaxoSmithKline, MRC, Syngenta, Unilever & Wellcome Trust.