| Arthritis can be extremely debilitating,
especially for otherwise healthy and active individuals. An effective
treatment can help them maintain the quality of life they enjoyed
before the disease slowed them down.
For years, people with osteoarthritis, a very common degenerative
disease of ageing populations, have taken the popular over-the-counter
supplement glucosamine. This is because glucosamine, a chemically
simple sugar with a nitrogen atom, is an important component of the
supporting structure of joint cartilage.
| Glucosamine is a naturally occurring and very prevalent
compound. There are small amounts in the hard tissues
of the human body, where it is an important building
block of the complex carbohydrates that make up the
extra-cellular matrix of cartilage. In arthritis and
other rheumatic diseases, cartilage degenerates and
key molecules built from glucosamine are lost.
However, there are some deficiencies with this form
of glucosamine, cautions Dr. Anastassiades. "Glucosamine
is metabolized very rapidly, so in terms of over-the-counter
glucosamine, very little probably reaches your joints
as free glucosamine." In addition, while some studies
show that in certain concentrations it seems to inhibit
cell death, in other concentrations it seems to inhibit
cartilage cell growth. So it's a complex picture. On
the other hand, glucosamine is non-toxic and can be
used safely.
The source material for over-the-counter glucosamine
is chitin – a very abundant polymer in the animal
kingdom – from the shells of lobster and crab.
|
|
The rationale behind taking the supplement is that if you provide
one of the building blocks, perhaps you can help regenerate or repair
the cartilage. It's so popular, the market is estimated to be in the
billions of dollars.
Published studies into the effectiveness of taking glucosamine
(usually in the form of glucosamine sulfate, a salt of glucosamine)
have indicated that there is improvement in pain scores in osteoarthritis
sufferers. However, not all studies support this and the use of
glucosamine for osteoarthritis is still under active investigation.
Because of glucosamine's popularity and potential, scientists
and doctors who specialize in osteoarthritis have long felt that
the compound warranted a closer look. One of the research goals
was to discover if, by modifying the chemistry of glucosamine, its
properties could be enhanced.
Dr. Tassos Anastassiades, a researcher with the Canadian Arthritis
Network (CAN), recently discovered and patented a glucosamine derivative
called Anabu™ that does have different properties from glucosamine.
"It's expected that this derivative will have advantages over
the parent glucosamine," he says. That's great news for those
who suffer from the pain and stiffness of arthritis.
"We've taken the starting material, pure glucosamine, and
then chemically modified it. Specifically, the modification is on
the nitrogen atom of the sugar. This is the same atom that is naturally
modified by humans and other species, before glucosamine becomes
part of the structure of the cartilage of joints," explains
Dr. Anastassiades, who is based at Queen's University in Kingston.
"What we observed is that when we do these chemical modifications,
we come up with a class of compounds whose properties are quite
different from the parent compound. In particular, we don't find
some of the inhibitory effects that we see with higher concentrations"
(see sidebar).
CAN expertise advances commercialization
With the support of CAN, Dr. Anastassiades has patented Anabu™
and the Network is leading the licensing and commercialization process.
He's enthusiastic about what they've accomplished together. "It's
CAN's most advanced project from a commercialization point of view,
I believe. We have licensed the technology to a veterinary company
and we are looking, again through CAN, to licensing it for humans.
Several pharmaceutical firms have expressed an ongoing interest."
"The Network is tailor-made to do this kind of thing. They
offer an opportunity to work with the researcher and advance these
kinds of compounds in development before you seek a partnership
with a biotechnology or pharmaceutical company. The Networks of
Centres of Excellence play a very important role by providing a
much-needed addition in terms of technology transfer in Canada."
Anabu™ will likely be available for the veterinary market
within a couple of years. It is hoped that, not too long after that,
it will complete the rigorous testing and approval procedures required
for human use and be available to arthritis sufferers.
www.arthritisnetwork.ca
|
