4. Metabonomics & Metabolomics
• Metabonomics:The quantitative measurement
of the time-related “total” metabolic response
of vertebrates to pathophysiological
(nutritional, xenobiotic, surgical or toxic
stimuli)
• Metabolomics:The quantitative measurement
of the metabolic profiles of model organisms
to characterize their phenotype or phenotypic
response to genetic or nutritional
perturbations
5. Metabolomics Is GrowingGrowth in Metabolomics
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6. What is a Metabolite?
• Any organic molecule detectable in the
body with a MW < 1000 Da
• Includes peptides, oligonucleotides,
sugars, nucelosides, organic acids,
ketones, aldehydes, amines, amino
acids, lipids, steroids, alkaloids and
drugs (xenobiotics)
• Includes human & microbial products
• Concentration > 1µM
7. Why 1 µM?
• Equals ~200 ng/mL
• Limit of detection by NMR
• Limit of facile isolation/separation by
many analytical methods
• Excludes environmental pollutants
• Most IEM indicators and other disease
indicators have concentrations >1 µM
• Need to draw the line somewhere
10. Medical Metabolomics
• Generate metabolic “signatures” for
disease states or host responses
• Obtain a more “holistic” view of
metabolism (and treatment)
• Accelerate assessment & diagnosis
• More rapidly and accurately (and cheaply)
assess/identify disease phenotypes
• Monitor gene/environment interactions
• Rapidly track effects from drugs/surgery
12. Problems with Traditional
Methods
• Requires separation followed by
identification (coupled methodology)
• Requires optimization of separation
conditions each time
• Often requires multiple separations
• Slow (up to 72 hours per sample)
• Manually intensive (constant
supervision, high skill, tedious)
13. What’s the Difference
Between Metabolomics and
Traditional Clinical
Chemistry?
Throughput
(more metabolites, greater
accuracy, higher speed)
15. Advantages
• Measure multiple (10’s to 100’s) of
metabolites at once – no separation!!
• Allows metabolic profiles or
“fingerprints” to be generated
• Mostly automated, relatively little
sample preparation or derivitization
• Can be quantitative (esp. NMR)
• Analysis & results in < 60 s
16. NMR versus MS
• Quantitative, fast
• Requires no work
up or separation
• Allows ID of 300+
cmpds at once
• Good for CHO’s
• Not sensitive
• Needs MS or 2D
NMR for positive ID
• Very fast
• Very sensitive
• Allows analysis or
ID of 3000+ cmpds
at once
• Not quantitative
• Not good for CHOs
• Requires work-up
• Needs NMR for ID
18. Quantitative vs. Chemometric
• Identifies compounds
• Quantifies compds
• Concentration range
of 1 µM to 1 M
• Handles wide range of
samples/conditions
• Allows identification of
diagnostic patterns
• Limited by DB size
• No compound ID
• No compound conc.
• No compound
concentration range
• Requires strict sample
uniformity
• Allows identification
of diagnostic patterns
• Limited by training set
29. Why Metabolomics For
Transplants?
• Relatively non-invasive (no need for
biopsy, just collect urine, blood or bile)
• Can be quite organ specific
• Very fast (<60 s for an answer) & cheap
• Metabolic changes happen in seconds,
gene, protein and tissue changes
happen in minutes, hours or days
• Allows easy longitudinal monitoring of
patient (or organ) function (pre&post op)
33. Why NOT Metabolomics For
Transplants?
• Still an early stage technology – not
“ready for prime time”
• Metabolites are not always organ
specific and not always as informative
as protein or gene measures
• Still defining signature metabolites and
their meaning
• Still don’t have a complete list of
human metabolites
34. Human Metabolome Project
• Purpose is to facilitate Metabolomics
• Objective is to improve
– Disease identification
– Disease prognosis & prediction
– Disease monitoring
– Drug metabolism and toxicology
– Linkage between metabolome & genome
– Development of software for metabolomics
35. Concluding Comments
• Metabolomics is rapidly becoming the
“new clinical chemistry”
• Metabolomics complements genomics,
proteomics and histology
• Metabolomics allows probing of rapid
physiological changes or events that
are not as easily detected by
microarrays or histological methods
• Canada is actually leading the way (at
least for now) in this field