While the research involved only 18 patients and was designed primarily to look at the safety of such a procedure and not its effectiveness, it is creating significant buzz in the neuroscience community because the results appear to contradict a core belief about brain damage — that it is permanent and irreversible.
The results, published in the journal Stroke, could have implications for our understanding of an array of disorders including traumatic brain injury, spinal cord injury and Alzheimer’s if confirmed in larger-scale testing.
The work involved patients who had passed the critical six-month mark when recoveries generally plateau and there are rarely further improvements. [...]
The one-time therapy involved surgeons drilling a hole into the study participants’ skulls and injecting stem cells in several locations around the area damaged by the stroke. These stem cells were harvested from the bone marrow of adult donors. While the procedure sounds dramatic, it is considered relatively simple as far as brain surgery goes. The patients were conscious the whole time and went home the same day.
“Their recovery was not just a minimal recovery like someone who couldn’t move a thumb now being able to wiggle it. It was much more meaningful. One 71-year-old wheelchair-bound patient was walking again,” said [Gary] Steinberg [the study’s lead author and chair of neurosurgery at Stanford] who personally performed most of the surgeries.
Steinberg said that the study does not support the idea that the injected stem cells become neurons, as has been previously thought. Instead, it suggests that they seem to trigger some kind of biochemical process that enhances the brain’s ability to repair itself.
“A theory is that they turn the adult brain into the neonatal brain that recovers well,” he explained.
Nicholas Boulis, a neurosurgeon and researcher at Emory University, said the study appears to support the idea that there may be latent pathways in the brain that can be reactivated — a theory that has been “working its way to the surface” over the past few years.