Parkinson’s could be treated by zapping brain with electricity

By Mark Waghorn via SWNS

Scientists have found a way to make DBS (deep brain stimulation) more precise - improving effectiveness of the therapy for people with Parkinson's disease.

Electrodes deliver high frequency jolts to a targeted area - changing signals that cause symptoms of tremor and slow movement.

A pulse generator - similar to a heart pacemaker - is placed under the skin around the chest or stomach area.

It is connected to one or two fine wires inserted into specific areas of the brain.

Currently, if the stimulator is turned off symptoms return immediately. The new technique could change that.

"By finding a way to intervene that has long-lasting effects, our hope is to greatly reduce stimulation time, therefore minimizing side effects and prolonging battery life of implants," said Study leader Professor Aryn Gittis, of Carnegie Mellon University, Pittsburgh.

The key lies in specific classes of neurons within the brain's motor circuitry identified by the US team four years ago.

Targeting them provide long-lasting relief of symptoms in rodent forms of Parkinson's models.

The researchers used optogenetics that controls genetically modified neurons with light. But the technique is not suitable for humans.

Gittis and colleagues have since been seeking an alternative strategy for patients.

Experiments on mice using the new DBS protocol of short electrical bursts were equally successful.

"This is a big advance over other existing treatments. In other DBS protocols, as soon as you turn the stimulation off, the symptoms come back," said Gittis.

"This seems to provide longer lasting benefits - at least four times longer than conventional DBS."

Quick jolts are delivered to neurons in the globus pallidus - an area of the brain in the basal ganglia which controls movement.

Gittis said researchers have been trying for years to find ways to stimulate specific types of cells.

"That concept is not new," she said. "We used a 'bottom up' approach to drive cell type specificity.

"We studied the biology of these cells and identified the inputs that drive them. We found a sweet spot that allowed us to utilise the underlying biology."

First author Dr. Teresa Spix, from the same lab, said scientists do not yet fully understand why DBS works.

"We're sort of playing with the black box," said Spix. "We don't yet understand every single piece of what's going on in there, but our short burst approach seems to provide greater symptom relief."

"The change in pattern lets us differentially affect the cell types."

Spix is excited about the direct connection the finding in Science has to clinical studies.

"A lot of times those of us that work in basic science research labs don't necessarily have a lot of contact with actual patients," she said.

"This research started with very basic circuitry questions but led to something that could help patients in the near future."

Neurosurgeons at Pittsburgh's Allegheny Health Network (AHN) are now set to carry out a safety and tolerability study in Parkinson's patients.

They will be followed for 12 months to assess improvements in motor symptoms and frequency of adverse events.

"Aryn Gittis continues to do spectacular research which is elucidating our understanding of basal ganglia pathology in movement disorders," said Dr. Nestor Tomycz, of AHN.

"We are excited her research on burst stimulation shows a potential to improve upon DBS which is already a well-established and effective therapy for Parkinson's disease."

Dr. Don Whiting, chief medical officer at AHN and one of foremost experts in DBS, said the new protocol opens doors for experimental treatments.

"Aryn is helping us highlight in the animal model things that are going to change the future of what we do for our patients," said Whiting.

"She's actually helping evolve the care treatment of Parkinson's patients for decades to come with her research."

Famous sufferers include comedian Sir Billy Connolly, actor Michael J. Fox and Sweet Caroline singer Neil Diamond.

"This work is really going to help design the future technology we're using in the brain and will help us to get better outcomes for these patients," said Tomycz.

The UK has around 145,000 sufferers - with cases set to almost triple over the next two decades. There is no cure.

Parkinson's UK says the main treatment is medication - with DBS provided when drugs no longer control symptoms.

It says: "Deep brain stimulation for Parkinson's may be an option for people whose symptoms are no longer controlled well by the best available medication for their condition.

"It is not a cure and does not stop Parkinson's from progressing. But in many cases it has given people with the condition better control of their motor symptoms including tremor, speed of movements and involuntary movements.

"Like all types of surgery, there are risks involved with deep brain stimulation.

"Make sure you have spoken to your specialist and understand what complications there could be before going ahead. Ask them to write anything down that you are unsure about."