Scientists from Sweden say they have made significant progress in the search for a new treatment for Parkinson’s disease.
Though the research, published in Nature Biotechnology, is still preliminary and the therapy not yet ready to be tested in humans, experts say it could one day help the millions of people living with the neurodegenerative disease.
Researchers from the Karolinska Institute tested whether certain brain cells could be manipulated to take on the role of those destroyed by Parkinson’s.
They first showed in laboratory experiments that it was possible to convert non-neural human brain cells called astrocytes into dopamine neurons, which degenerate and die in the brains of people suffering from Parkinson’s disease.
“These are two specialized cells that do not spontaneously convert into one another,” study author Ernest Arenas, a professor at Karolinska Institute’s Department of medical biochemistry and biophysics, told CBS News. “However, when we used diverse chemicals and genes important for the development of immature brain cells into functional dopamine neurons, we found that it was possible to convert astrocytes into dopamine neurons.”
The researchers then tested whether this could be done in mice with Parkinson’s – and if the therapy would improve their condition.
After two weeks, they reported that astrocytes in the brains of the mice started to become dopamine neurons. At five weeks, the mice recovered some of their motor functions such as posture, motility and walking pattern.
Current treatments for Parkinson’s only address symptoms, not the cause of the disease itself.
While much more research is needed before the treatment can be tested in humans, Arenas says it could one day lead to an approach “to change the course of disease and halt or even reverse motor deficits in Parkinson’s disease patients.”
Aside from being in early stages, the research is limited in several ways, the study authors say.
First, Arenas notes that although dopamine neurons are the main cell type affected in Parkinson’s disease -- and those responsible for the characteristic motor symptoms -- other cell types are affected, particularly as the disease progresses. Therefore, additional strategies to treat these other cell types will be needed in the future.
Additionally, this type of therapy would involve surgery, and therefore could be riskier compared to other treatments on the market. However, with people living longer in most societies, more severe forms of disease are currently being seen, Arenas said, and people are suffering longer.
“We thus think that cell replacement therapies, because of its potential to change the course of disease, may become the method of choice in the future,” he said.
The authors say now that they know the treatment technique is possible, future research will concentrate on making it safer and developing it into a method that could be applied in a clinical setting.
“Our goal and hope is that all these studies will lead to the development of a safe and efficient cell replacement therapy for Parkinson’s disease in which no cell transplantation or immunosuppression is necessary,” Arenas said.