Parkinson's trial suggests growth factor has regenerative effects in brain

Date: Feb-19-2015The first trial to test the effect of a growth-factor compound in humans

with Parkinson's disease has shown promising results. A report in the Journal of

Clinical Investigation raises the hope that one day we will see regenerative

treatments for Parkinson's disease that use the brain's own protective mechanisms to

halt the loss of brain cells and restore dopamine levels.

PET scans show dopamine signaling activity before and after treatment - white areas signify more intense activity.
Image credit: Lund University

There are millions of people worldwide living with Parkinson's disease - a

progressive movement disorder that results from the loss of brain cells that produce

the chemical dopamine.

The symptoms of Parkinson's - which include tremor, stiffness, slowness and

impaired balance - gradually worsen and patients experience increasing difficulty

walking, talking and taking care of themselves.

Research into the effects of platelet-derived growth factor or PDGF started over

10 years ago with studies in animals. These found that the growth factor reduces

symptoms of Parkinson's, improves motor skills, and restores levels of dopamine in

the brain. They also suggest PDGF repairs neurons and nerve fibers.

PDGF is safe for Parkinson's patients and may have regenerative effects

In their double-blind, randomized, placebo-controlled trial - the first in human

patients - researchers at Lund University and Karolinska Institutet in Sweden tested

the safety and tolerability of PDGF in 12 patients with Parkinson's disease.

Fast facts about Parkinson's disease

Parkinson's disease arises through loss of dopamine-producing brain cells

It usually affects people over the age of 60

At present there is no cure, but there are drugs that provide dramatic relief

from the symptoms.

Find out more about Parkinson's

disease

The treatment - PDGF or placebo - was delivered via a pump surgically implanted in the abdomen, with an internal catheter that went up into the brain. The pump delivered the drug for 12 days, and patients were followed for another 73 days, during which the pump delivered an infusion of saline.

The results show that PDGF does not cause serious, unresolvable side effects. The

researchers were also encouraged by other results, which they discovered when they

examined PET scans of the patients' brains taken 4 months after treatment.

The PET scan images showed that in the patients who received the active

treatment - as opposed to placebo - levels of dopamine signaling were not only

maintained, but even increased.

First author Gesine Paul, research group leader and Associate Professor at Lund

University, explains that in Parkinson's disease, the brain is continuously losing

nerve cells, causing a gradual decline in dopamine levels. But:

"What we have seen is that the patients who received the highest dose did not

have the same decrease in these signals as the placebo-treated patients. Instead, we

have actually seen an increase in signaling here."

With PDGF it may be possible to stimulate brain to slow or halt Parkinson's

The team is very excited about the results because they indicate PDGF can restore

structures in the brain that are lost in Parkinson's disease - something current

treatments can't do. Prof. Paul notes:

"Although we still have a long way to go our study suggests that it

may be possible to stimulate the brain's built-in protective mechanisms in order to

slow or halt disease progression."

The team says clinical trials in larger groups of patients are now needed and

they hope that journey will be shorter than the one that has brought them to this

point. They anticipate these larger trials will take place in Sweden, Germany and

England.

They also want to examine and understand the detailed mechanisms responsible for

the repair and regeneration that PDGF seems to trigger in the brain.

The trial was carried out in collaboration with the Swedish biotech company Newron Sweden who will continue to partner the team in future trials. Funding came from Vinnova and the European Commission.

Meanwhile, Medical News Today has learned that difficult-to-treat

symptoms of Parkinson's appear to respond to low-

frequency deep brain stimulation. A study published recently in the journal

Neurology shows that patients with swallowing dysfunction and freezing of

gait experienced more significant improvement after low-frequency treatment compared

with the more usual high-frequency deep brain stimulation.

Written by Catharine Paddock PhD

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.