Innovative concept may give hope to Parkinson's sufferers

A team of University of Otago neuroscientists led by Dr Louise Parr-Brownie are breaking ground in a new treatment for Parkinson's disease that could offer sufferers much better quality of life. Photo / Supplied

Otago team leads research which could offer sufferers of disease a better quality of life

An innovative concept which would override the damaging brain patterns of Parkinson's disease could give new hope to sufferers.

While there is no cure for the neuro-degenerative condition, a team of University of Otago neuroscientists are breaking ground in a new treatment that centres on the little-understood approach of optogenetics - something which could offer sufferers much better quality of life.

Preliminary findings, published in the Journal of Neuroscience, have shown its application on rats has led to an improved ability to recover movements.

Fundamental to the approach was the understanding that the movement deficits of Parkinson's disease were caused by abnormal activity in the brain which changed the way cells fired, study leader Dr Louise Parr-Brownlie explained.

"But if we could override a Parkinsonian brain by putting in actual neural coding and replaying activity from a normal brain, does that restore movement?"

The concept involved inserting into the brain a specially-coded viral vector which introduced a light-responsive protein into cells.

By shining blue light on the proteins, they could be stimulated and used to influence neurons to behave normally. "With this technology, we can do all sorts of things - in our case, we can over-ride an abnormal pattern and put in a normal one," she said.

"We recorded activity from a control rat brain, and we've then replayed that into our Parkinsonian one - it worked, and movements were improved significantly."

The approach, however, could never cure Parkinson's, as sufferers typically showed symptoms when around 70 per cent of the dopamine-producing cells had already been lost.

While viral vectors are being used in Parkinson's patients in overseas trials, none of these studies are being undertaken in New Zealand.

Dr Parr-Brownlie and her team are leading the world in their specific approach.

"If we take this basic knowledge and apply it to the brain continuously, how good could the improvement be?

"We don't know that, though I would predict it would be better than what we've already shown."

Parkinson's New Zealand chief executive Deirdre O'Sullivan was "delighted" a New Zealand team was playing such a leading role in the field.

Thinking around the problem

What is Parkinson's disease?

It is the progressive degeneration of the dopamine-producing cells in the brain leading to symptoms that include tremors, stiffness and rigidity, and slowness of movement. It affects 1-2 per cent of Kiwis over 60 -- about 10,000 people -- and that rate is expected to double over the next 20 years.

Is there a cure?
No - and symptoms typically only become clear after the sufferer has already lost 70 per cent of the dopamine-producing cells. The best-known treatments include drugs and "deep brain" stimulation, where a stopwatch-sized device is implanted in the chest and a wire inserted into the brain to electrically stimulate the areas that control movement.

What are the NZ researchers exploring?
A new approach known as optogenetics. They first introduce a specially-coded viral vector into the brain, which later produces a light-responsive protein. Shining a blue light on these proteins can stimulate and influence the protein ultimately allowing scientists to over-ride the abnormal patterns of a Parkinsonian brain with the "replayed" patterns of normal brain circuitry. It's hoped this might help restore movement deficits in the brain.