Discovery by Johns Hopkins scientists provides insight into onset of ALS

Researchers at Johns Hopkins say a recent discovery about central nervous system cells holds promise for interrupting the progress of ALS (amyotrophic lateral sclerosis), also known as Lou Gehrig's Disease.

In a study described online in Nature Neuroscience, the scientists found that, in mice bred with a gene mutation that causes human ALS, dramatic changes occurred in cells that create insulation for the nerves of the central nervous system—called oligodendrocytes—long before the first physical symptoms of the disease appeared. The Oligodendrocytes located near cells that govern movement died off at very high rates, and new ones regenerated in their place were inferior and unhealthy.

Researchers believe this regeneration of inferior cells plays a fundamental role in the early stages of the development of the fatal degenerative disease. They found that suppressing and ALS-causing gene in the oligodendrocytes significantly delayed the onset of ALS and prolonged survival of the mice by more than three months, a long time in the life span of a mouse.

"The abnormalities in oligodendrocytes appear to be having a negative impact on the survival of motor neurons," says Dwight E. Bergles, a co-author and a professor of neuroscience at the Johns Hopkins University School of Medicine. "The motor neurons seem to be dependent on healthy oligodendrocytes for survival, something we didn't appreciate before."

Added co-author Jeffrey D. Rothstein, a professor of neurology at Johns Hopkins and director of the Johns Hopkins Medicine Brain Science Institute. "These findings teach us that cells we never thought had a role in ALS not only are involved but also clearly contribute to the onset of the disease."