Page 27 - EUREKA! Summer 2018

When Maria DeRosa and Matthew Holahan met,

they saw that biochemistry and neuroscience
could be combined with nanotechnology to

advance the frontiers of health research.

nybody who visits Carleton To date, most PD treatments have with nanotechnology to advance the
chemistry professor Maria focused on alleviating the disease’s frontiers of health research, and they
ADeRosa’s laboratory on the symptoms, not its cause. But DeRosa started working together in 2010,
third floor of the university’s Steacie and Holahan had another approach investigating connections between
Building will see a landscape of in mind. “This project was science dopamine and conditions such as
labelled bottles, Styrofoam coolers, fiction at the beginning,” says DeRosa. schizophrenia and addiction.
refrigerators and long black counters “Finding the right aptamer was like Dopamine, which plays a role in
covered with beakers, computers and looking for a needle in a haystack. But both human pleasure and mobility, is
microscopes. In one corner, dozens we wanted to do something big.” as essential to bodily movement as
of thin plastic tubes fan out from In November 2016, after sifting motor oil is to an engine. Low levels
a machine the size of a bar fridge, through countless haystacks, of the neurotransmitter are linked
connecting amber bottles of clear, DeRosa and graduate students Erin to both addictive behaviour and
purple and golden liquids to a nozzle McConnell and Josh Callahan watched neurodegenerative disorders such as
inside a metal box. To an outsider, the expectantly as their synthesizer PD, which scientists believe may be
lab may look cluttered, but it’s ground made a new aptamer they had tied to alpha-synuclein accumulation.
zero for a meticulous research project named A-syn-1. Two months later, Together, DeRosa and Holahan had
that has the potential to help spark a test tubes containing A-syn-1 were identified an aptamer that binds to
medical breakthrough. sent to Holahan’s lab, where he was dopamine, but it proved difficult to
In 2016, for nine months, that conducting studies exploring levels of target dopamine in the brain, and
mechanical nozzle rhythmically dopamine — a “chemical messenger” they couldn’t secure the funding they
whizzed and clicked as it squirted that is responsible for transmitting needed for exploratory studies, so
droplets from the amber bottles into signals within the brain — in mice that they had to come up with a more
rows of tiny test tubes. Those bottles had been bred to develop PD-like focused research project. “It didn’t
contained a diverse set of reagents symptoms such as slow movements, help that this was something new, that
— compounds that cause chemical tremors and rigidity. These symptoms we had an untested idea,” DeRosa
reactions — which the machine, a are associated with the clumping of a says about shifting their investigation
MerMade synthesizer, used to create brain protein called alpha-synuclein. to alpha-synuclein. “Most people
billions of single-stranded DNA Holahan and PhD student Katelyn in neuroscience haven’t heard of
molecules. Suspended in drops of Ventura gave mice nine doses of researchers using aptamers in this
colourless liquid, these microscopic A-syn-1 over three months, but before way, so we couldn’t go to traditional
strands of DNA are called aptamers, they could even determine how funding sources.”
which bind to a variety of target much of the aptamer had made it It’s estimated that more than six
molecules and have a long list of into the rodents’ brains, they noticed million people around the world are
environmental, agricultural and health something incredible. The amount of affected by the mobility disorder
applications. alpha-synuclein had been cut in half. first characterized by English doctor
DeRosa’s research group, the James Parkinson 200 years ago. The
Laboratory for Aptamer Discovery After completing her PhD in number of Canadians diagnosed with
and Development of Emerging chemistry at Carleton in 2003 and PD is expected to exceed 164,000 by
Research (LADDER), wants to develop a postdoctoral fellowship at the 2031, according to Parkinson Canada.
aptamers for use in fertilizers that California Institute of Technology in After epilepsy and Alzheimer’s
seek out specific plants, for instance, 2004, DeRosa returned to Carleton as disease, PD is responsible for the
or to detect toxins in food and a faculty member in 2005. Holahan, third-highest healthcare costs in the
airborne chemicals. And through a who earned his master’s degree and country, and the debilitating and
series of collaborations with Carleton PhD in psychology at Montreal’s degenerative disease will only become
Neuroscience professor Matthew McGill University, arrived at Carleton more prevalent and more expensive
Holahan, she has also started a year later. His research focused on as baby boomers age. Parkinson’s
hunting for aptamers that may help memory, Alzheimer’s disease and predominantly affects people who
stop the second most common neural development. When the two are older than 60, although about 10
neurodegenerative brain disorder: met, they saw that biochemistry and percent of people with PD are younger
Parkinson’s disease (PD). neuroscience could be combined than 50, and it can start at a much

26 science.carleton.ca science.carleton.ca 27