In motorneuron disease (known as amyotrophic lateral sclerosis in the USA, sometimes also called Lou Gehrig’s disease) nerve cells that control movement, located both in the spinal cord and in the brain, degenerate and die. As a result, the muscles to which those nerve cells were connected eventually weaken and waste away. Patients lose their strength and the ability to move their arms, legs and body. Eventually the muscles in the diaphragm and chest wall fail, and the patient becomes unable to breathe without support.

Because nerve cells in both the spinal cord and the brain are affected in motorneuron disease, the prospect of treatment through replacement of these cells seems a distant goal. Any effective cell-replacement therapy would have to restore the function of both groups of nerve cells, and, as with other neurological disorders, ensure that the new cells become integrated into the existing circuits, so that the brain and spinal cord are able to function appropriately. For all these reasons, scientists feel that a great deal of laboratory research should be done before moving into clinical trials involving motorneuron disease patients.

Scientists believe that a more realistic approach is to use stem cells to alleviate the symptoms and even revert progression of the disease. When transplanted into the spinal cords of animals with motorneuron disease, stem cells appear to nurse the sick and injured nerve cells, preventing them from dying and improving their function. Scientists are hopeful that within the next few years they will know enough to test these treatments in patients, which they expect to be most helpful if administered shortly after diagnosis, when a patient begins to lose limb function but before paralysis sets in.

Relevant links:
The National Institute of Neurological Disorders and Stroke
Motor Neuron Disease (MND) Association
Scottish Motor Neuron Disease Association