Huntington’s Disease: Scientists Hope Their Success in Improving Survival in Mice Will Extend to Humans

For years, scientists have been working on a completely new concept that generates new neurons in mice with Huntington’s disease. They were able to demonstrate that the new cells could integrate into the brain’s existing neural networks replacing cells that were lost in HD, thus improving overall survival in the mouse models.

According to a study published in Nature Biotechnology, Rochester University Medical Center’s Steve Goldman, M.D., senior author of the study, stated that the recruiting of endogenous stem cells, those that participate in repairing the cells that have been lost through HD, is a new and entirely feasible concept for treating the disease.

The findings strongly suggest that glia reside in the adult brain and whether diseased or old, glia may be replaced by healthier and younger cells. Neurons activate chemical signals and glia modulate neuron signaling.

The researchers suggested that using healthy human glial cells may be a viable alternative to treating neurological disorders, including HD, that are characterized by troublesome glia cells.

About Huntington’s Disease (HD)

HD is a rare, genetic disorder, causing progressive degeneration of the nerve cells in the brain. HD currently affects over 30,000 people in the United States.

The disease usually appears between the ages of 35 through 55 or later.

It is characterized by a reduction in a type of neuron that is vital to motor control. HD causes involuntary movements, difficulty with coordination, and eventually cognitive decline followed by depression and death.

Currently there are no approved treatments to either modify or slow the fatal disease.

The Origin of the Study

For several decades, Dr. Goldman had studied neural plasticity which is a reorganization of the nervous system’s structure and function after injuries.

Canaries and other songbirds have captured the attention of Dr. Goldman and his associate Fernando Nottebohm since the 1980s. The process is called adult neurogenesis.

The scientists observed that when learning new songs, new neurons were added to areas of the brain that were responsible for the bird’s vocal control. The name of this process is adult neurogenesis.

Dr. Goldman further explained that the work they performed provided the team with the instructions they needed to understand how to add new neurons to adult brain tissue.

The ability to create new neurons already exists. However, although the ability to produce neurons continues into early development, the neural stem cells no longer generate neurons. Instead, they turn their attention to the production of glia in the central nervous system.

There are certain parts of the human brain that continue to produce neurons well into adulthood, such as the hippocampus.

Conversely that capability is turned off in the striatum, which is a region in the brain that is ravaged by HD.

Trading Sickness for Health

For the past ten years Dr. Goldman and his associates searched for the chemical signaling that could instruct neural stem cells to differentiate between creating glia cells versus creating neurons. At one point, they reverted back to their earlier research with canaries and found the answer.
Their findings indicate that glia cells residing in the human brain may be replaced whether they are aged or diseased following the introduction of younger, healthier cells. The University’s recent press release was entitled: “Trading Sickness for Health.”