An experimental study funded by Parkinson’s UK has demonstrated promising results for infusion of a naturally-occurring protein called GDNF directly into the brain, offering hope that damaged brain cells in Parkinson’s disease patients could be restored.

GDNF, also known as glial cell-line derived neurotrophic factor, was developed by Canadian biopharmaceutical firm MedGenesis Therapeutix .

The study was carried out with support from The Cure Parkinson’s Trust and in collaboration with the North Bristol NHS Trust.

Although the trial did not show significant difference between the treatment group and placebo arm, the researchers found signs of improvements in participants who received GDNF.

Trial principal investigator Alan Whone said: “The spatial and relative magnitude of the improvement in the brain scans is beyond anything seen previously in trials of surgically delivered growth-factor treatments for Parkinson’s.”

A total of 41 participants were enrolled into the study and underwent robot-assisted surgery to have tubes placed into their brains. This allowed direct infusion of GDNF to the affected brain areas.

Of the total participants, 50% of the patients were given monthly GDNF infusions and the remaining half received monthly placebo infusions. After nine months, all patients were offered the GDNF infusions for an additional nine months.

Brain scans after nine months showed no changes in placebo arm but revealed improvement in a key brain area affected due to Parkinson’s in patients who received GDNF. The researchers believe that this could indicate reawakening and restoring of damaged brain cells.

“The spatial and relative magnitude of the improvement in the brain scans is beyond anything seen previously in trials of surgically delivered growth-factor treatments for Parkinson’s.”

At 18 months, both groups demonstrated moderate to large improvements in symptoms compared to their scores prior to the study.

Whone added: “This represents some of the most compelling evidence yet that we may have a means to possibly reawaken and restore the dopamine brain cells that are gradually destroyed in Parkinson’s.”

The team is currently working on exploring possible approaches for further studies of the protein.