Queensland research holds promise for those stricken with Parkinson's
disease
Bernadette Condren
22oct05(The Courier Mall) - TREMORS, depression, incontinence,
incapacity and dementia – there is little to look forward to with a
diagnosis of Parkinson's disease.
In most people with the disease, their vulnerable outward appearance
belies a steely resolve to live life to the full while they can still
remember there's a life worth living.

Parkinson's disease was first described as "shaking palsy" and was
discovered in 1817 by James Parkinson – a social reformer and
physician born in London in 1755.

Since then, there has been little progress in understanding the
disease, but two Queensland research groups are making significant
advances in not only finding the cause of the disease, but also in
how to tackle its debilitating symptoms.

Griffith University professor Alan Mackay-Sim is continuing his work
on developing adult stem cell therapy for Parkinson's disease.

Although the research is still in its early days, Professor Mackay-
Sim's team is taking a two-pronged approach.

They are studying brain cells from people with the disease to see
what the biological cause of the disease is, and they are working on
transplanting stem cells to replace those cells that have died.

University of Queensland medical lecturer and head of the Parkinson's
Disease Research Group George Mellick is also making inroads into
understanding the disease. Dr Mellick's team is focusing mainly on
the cause of Parkinson's and its risk factors, including
environmental and genetic factors.

Parkinson's is in the media spotlight right now as the fifth
international symposium of the Asian and Pacific Parkinson's Disease
Association gets under way in Melbourne.

The disease is a neuro-degenerative disorder that affects between
7000 and 8000 Queenslanders and about 30,000 Australia-wide. It
involves the deterioration or death of dopamine-producing cells in a
part of the brain called the substantia niagra, which is found in the
brain stem between the main part of the brain and the spinal cord.

Dopamine is a chemical messenger, and it is the lack of dopamine that
is largely responsible for the symptoms of Parkinson's.

Neurologist and head of Parkinson's Queensland John O'Sullivan says
symptoms vary between people with the disease but,
characteristically, patients experience tremors, a lack of co-
ordination – known as bradykinesia – rigidity and, as the disease
progresses, lose their balance more readily.

"It really affects a broad spectrum of brain function, and is
responsible for quite a degree of disability," Dr O'Sullivan said.

"We don't really know what causes it. We understand that for some
reason, these cells in particular seem to be vulnerable, and we don't
know exactly why that is.

"There's evidence emerging that the normal repair mechanisms, the
housekeeping role, of parts of the cell that stop the cell dying and
keep them working normally seems to stop functioning."

Parkinson's is not a pretty disease. People diagnosed with it will
see their handwriting deteriorate, their gait reduced to a shuffle,
their ability to wash and dress themselves eroded to complete
incapacitation, their speech soften to the point of not being able to
be heard, and independent eating will become a thing of the past.

"It is a slowly progressing disease, so people have it for years and
years rather than a rapid deterioration from weeks to months," he
said.

"That all sounds pretty dismal, but because it's a relatively select
group of cells that are involved, we can replace the chemical
dopamine in a variety of ways with pharmacological drugs, which are
really quite effective in the majority of cases – at least for some
time."

Thanks to publicity the disease has received – through the work and
the profiles of US actor Michael J. Fox, diagnosed in 1991 with young-
onset Parkinson's, and boxer Muhammad Ali, who was diagnosed in the
early 1980s – many millions of dollars have been channelled into
research at different centres across the world.

Professor Mackay-Sim said Parkinson's was a good candidate for stem
cell therapy because one cell type has been identified as being
chiefly responsible.

"We know where the loss is and we just have to get those cells back
in," he said. "We do that by injecting the cells directly into the
brain to see if they are therapeutic."

The professor and his team are also investigating the biology of the
dopamine-producing cells by comparing those in people with
Parkinson's to those in non-sufferers.

Dr Mellick sums up his research thus:

"It's a complex disease and probably results, in most people, from a
complex interaction between inherited factors and environmental
factors."