Millions of Parkinson’s sufferers have been given hope of of a cure after tests showed how human stem cells can be used to reverse the effects of the disease.
Scientists converted human embryonic stem cells into nerve cells that produce the brain chemical dopamine, which is known to play a role in the development of Parkinson’s.
When these nerve cells were transplanted into the brains of mice, they released dopamine which gradually eradicated the Parkinson’s symptoms.
Any symptoms of the illness in the animals were eliminated over a three to five-month period, the team from the Sloan-Kettering Institute in New York found.
The researchers hope a similar solution can be developed for humans and trials are already planned.
Until now a similar approach in mice using human embryonic cells hasn’t worked well, triggering the formation of tumor-like structures.
But Lorenz Studer’s team developed a new method for creating cells, closer to the way they naturally form.
Their findings have now been published in the journal Nature.
Lead researcher Dr Studer said: ‘We see a real opportunity to develop this into an actual cell therapy for patients.
‘It is now more of an “engineering problem” than a scientific one.’
The cells were also successfully transplanted into rhesus monkeys, whose biology is closer to that of humans, but results are still being monitored.
Currently there is no cure for Parkinson’s, which causes the deterioration of the brain’s dopamine-producing cells.
This affects the brain’s ability to send messages, leading to loss of muscle function, reduced movement and tremors.
There are drugs that increase dopamine levels in the brain and help control symptoms, but they can cause side-effects, such as involuntary movements.
Dr Studer’s team now plans to create the new cells on a larger scale over a 12-month period, providing enough to graft 100 human patients after extensive safety testing.
Tilo Kunath, a stem-cell scientist at the University of Edinburgh, who wasn’t involved in the study, told Fox News: ‘This is a big leap. To see a complete rescue, and a lasting rescue, is unheard of in these animal models.’
Parkinson’s disease affects around 120,000 people in the UK and men are statistically slightly more likely to develop it than women.
Symptoms usually appear in people who are over the age of 50, however, younger people can also be diagnosed with the neurological condition.