Condition: Replacing nerve cells in the central nervous system (the brain and spinal cord) that have been destroyed by brain diseases or injury could possibly help people recover and regain function.
Background: The process of growing or re-growing nerve cells is called neurogenesis. It is most active before birth but continues even in adults. Scientists are now figuring out how to stimulate neurogenesis to treat patients with diseases such as Parkinson’s disease, stroke, traumatic brain injury, spinal cord injury, and cerebral palsy. For example, exercise seems to stimulate neurogenesis. Other treatment approaches start in the laboratory with immature cells from the bone marrow, called stem cells. These stem cells can be treated so they will mature into nerve cells, which can then be put back into the brain or spinal cord to replace damaged cells. Each of these steps – retrieving the stem cells, treating them so they become the right type of cells, and then delivering them to the patient – is complicated and there is still a lot to learn.
Risk Factors: Studies of this type of treatment are just beginning, so not much is known about whether some patients would be more likely to benefit than others. For example, there may be differences based on the patient’s age or the stage of the disease. Scientists also want to know if growing new nerve cells improves a person’s ability to move or do other activities. And they are also studying if these treatments might have bad side effects.