A research project that includes work done by 11 different institutions has tested the ability of neural stem cells to treat Lou Gehrig’s disease, which is also known as amyotrophic lateral sclerosis or ALS. ALS affects neurons in the central nervous system, particular in those cells in the spinal cord that allow voluntary movement (motor neurons). These neurons die off, and the patient loses the ability to move and, eventually, to breath. There is no presently no cure for this catastrophic and horrific disease.
Stem cell treatments have shown some success in laboratory animals, and this recent study examined the ability of neural stem cells, which have the ability to form neurons or those cells that support neurons, glial cells, to treat mice with a form of ALS that seems to closely resemble the disease presented by human ALS patients.
The combined work of these 11 different institutions showed that when these cells were transplanted into the spinal cords of laboratory mice afflicted with a form of ALS, symptoms of the disease decreased and the progression of the disease was greatly altered. When treated mice were compared with untreated mice, their movement ability and breathing were much better. Even more remarkable was the ability of these stem cells to slow the progression of ALS. Twenty-five percent of the treated mice survived for one year or more, which is three-four times longer than the untreated mice.
Even though neural stem cells can form neurons and other types of nervous system-specific cells, the neural stem cells in this experiments did not benefit mice by differentiating into new neurons. Instead, the transplanted stem cells prolonged the life of the troubled tissues by secreting molecules that are beneficial to the health of neurons and other cells in the nervous system. This menagerie of helpful molecules made by neural stem cells also stimulates other native cells in the nervous system to make their own fair share of protective molecules.
The transplanted neural stem cells also decreased the production of toxins by the diseased tissues and also diminished inflammation in the spinal cord.
In the words of the senior author of this study, Evan Y. Snyder, the director of Sanford-Burnham‘s Stem Cell and Regenerative Biology Program: “We discovered that cell replacement plays a surprisingly small role in these impressive clinical benefits. Rather the stem cells change the host environment for the better and protect the endangered verve cells. This realization is important because most diseases are now being recognized as multifaceted in their cause and their symptoms – they don’t involve just one cell type or one malfunctioning process. We are coming to recognize that the multifaceted actions of the stem cell may address a number of these disease processes.”
These studies demonstrate the potential neural stem cells hold for treating ALS and other nervous system disorders. However, Snyder tempered these results with this measured optimism: “While not a cure for human ALS, we believe that the careful transplantation of neural stem cells, particularly into areas that can best sustain life – respiratory control centers, for example – may be ready for clinical trials.”