U of A's 800 MHz nuclear
magnetic resonance spectrometer
Photo credit: Courtesy of:
University of Alberta |
Breakthrough research at the University
of Alberta should soon lead to quicker and better detection
of diseases, even those that are rare and difficult
to diagnose.
The U of A research, which vastly
expands the identification of chemicals in the human
body, should help doctors within three to five years
to more routinely determine which diseases their patients
have.
Abnormal levels or combinations
of certain metabolites — chemicals such as cholesterol,
blood glucose or testosterone — may signal a patient
has diabetes, Alzheimer's or a particular cancer.
While the technology needs to be
developed, doctors or even the general public could
eventually carry hand-held devices that could test their
blood or urine for the 2,500 chemicals or metabolites
now identified through the Human Metabolome Project.
"I would go so far as to say that
Star Trek medicine is upon us today," said Bill McBlain,
senior vice-president of research at the U of A. "This
project has — and I'm not exaggerating — the
potential to totally revolutionize the diagnosis, the
understanding and the treatment of disease and other
related health issues."
David Wishart, the leader of the
$7.5 million Human Metabolome Project, began the undertaking
in 2004 and has since detected 2,500 metabolites in
the human body — more than three times the 700
previously identified.
Using huge machines called nuclear
magnetic resonance spectrometers (the chemical equivalent
to an MRI machine for humans), Wishart and his team
also found 1,200 drugs and 3,500 food components that
appear in humans naturally and from the food they eat,
the drugs they take or the air they breathe. Salt, vitamins
and steroids are all metabolites.
"Knowing this information, we can
start associating different diseases with different
combinations or concentrations of metabolites," said
Wishart, a biological sciences and computing science
professor at the U of A. "This could increase the speed,
the sensitivity, the specificity of medical diagnosis
by 100-fold. It could also allow many new or hard-to-diagnose
diseases to be detected far earlier and at significantly
reduced costs."
Currently, common urine or blood
tests test for between eight and 20 different metabolites
in the blood, Wishart said. A person with diabetes may
be identified by sugar in the urine, yet many other
metabolite markers may also help the doctor determine
what's going on. Without seeing all the ingredients,
those tests will miss a lot and proper diagnoses won't
be made, Wishart said.
He became interested in figuring
out the body's metabolite soup after a relative of his
went undiagnosed with Fanconi syndrome for 15 years.
The syndrome made it difficult for her kidneys to properly
absorb and distribute sugars, amino acids and other
compounds to the blood.
When Wishart analyzed the metabolite
recipe in her body, he discovered extremely high concentrations
of some chemicals. "If we had the way of identifying
that particular pattern, my relative would have been
diagnosed within minutes instead of 15 years," he said,
noting that companies in Canada, the United States,
the Netherlands and Germany are already using the information
in Wishart's metabolome database to develop diagnostic
tests.
Wishart and his research team have
laid out the chemical recipes for 150 diseases, including
rare ones such as cystinuria, which creates kidney and
bladder stones, or glycerol kinase deficiency, which
causes bone fractures and physical and mental retardation.
Now, he said, it's up to physicians
to determine the metabolite recipes of other diseases.
The dean of medicine at the U of
A is testing blood from patients with pneumonia, hop-ing
to determine how meta-bolite signatures can quickly
alert doctors to viral versus bacterial pneumonia. Such
a distinction is difficult to make, Wishart said, so
patient conditions sometimes worsen while they wait
for a clear diagnosis.
"It's not only diagnostic, it could
be prognostic," said Wishart, noting that a certain
blood cocktail or spike in metabolites could predict
the later onset of a disease. "It's also very useful
for monitoring."
Martin Godbout, president and chief
executive officer of Genome Canada, said Wishart's metabolome
project is key in understanding the human body. "It
is as important as the genome project," Godbout said,
referring to the mapping of the human gene first announced
in 2000.
He said humans are made of four
main components: genes, proteins, metabolites and regulatory
elements such as puberty. Scientists have yet to fully
map the human protein as they first did the gene and
now the metabolome. "You need the four legs of the stool
to see how it works. Every leg is as important as the
other."
Material reprinted with the
express permission of the Edmonton Journal.
|
