Human stem cells help ease Parkinsons in primates

A cutting-edge research study of human stem cells in primates with Parkinsons disease has shown that cell transplantation may ease the symptoms of the disease.

Washington, July 11 : A cutting-edge research study of human stem cells in primates with Parkinson's disease has shown that cell transplantation may ease the symptoms of the disease.

Dr. Paul R. Sanberg, Professor of Neurosurgery at the University of South Florida, says that the NIH-funded study showed that some stem cells turned into astrocytes, a supportive brain cell that produces neuron-nourishing chemicals.

In the course of study, only a small number of stem cells turned into dopamine-producing cells-not enough to improve the primates' function by replacing missing neurons.

The researchers also identified in the brains of the primate recipients a significant amount of dopamine-producing neurons that were not derived from stem cells.

According to them, the results suggest that stem cells may actually trigger the brain's own self-repair mechanisms by pumping out molecules that boost nerve survival and blood vessel development and decrease neural degeneration.

"We at the Center for Aging and Brain Repair at USF Health have been arguing, for some time now, that stem cells are important for brain repair because they provide growth factors and because they send signals to the brain to help it repair itself," said Dr. Sanberg, whose expert commentary 'Neural Stem Cells for Parkinson's Disease: To Protect and Repair' has been published online in the Proceedings of the National Academy of Sciences of the United States of America (PNAS).

"This study in primates showed the same effects - that the stem cells are there to act as facilators of repair versus the original hypothesis that stem cells are transplanted to merely replace an injured cell," Dr. Sanberg added.

The study, conducted by Gene Redmond and colleagues at Yale and Harvard Universities and the Burnham Institute, has relevance to all audiences because it is the first to look at stem cells in primates with Parkinson's disease.

"This was one of the first studies to look at stem cells in primates with Parkinson's disease. It's the first step in translating that research," Dr. Sanberg said.

"We hear about new sources of stem cells monthly, but how we take those cells and treat disease is going to be a significant amount of translational work. This is one of the first studies that starts that process - looking at primates before going into people with Parkinson's disease," he added.

He, however, conceded that the translational research in primates raised questions that needed to be addressed before moving to human trials, including determining the most effective cell dosing and brain sites to target.

"Pending further pre-clinical studies, the results so far from the current study are supportive for developing a safe and effective stem cell treatment for Parkinson's disease," he writes in the commentary, which will also be published in the magazine edition of PNAS.

ANI