Stem Cell Researchers Reveal Possible Breakthrough Towards Treating Neurodegenerative Diseases

Treating Neurodegenerative Diseases

Scientists from the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, at the UCLA (University of California, Los Angeles) managed to create a laboratory model of the disorder named ataxia telangiectasia, a very rare genetic disease, through the use of induced pluripotent stem cells (iPSC). Their results show that several new drugs have positive effects, thus opening new doors for future treatment plans against neurodegenerative disorders. The induce pluripotent stem cells were derived from the skin of the patient, rather than from embryos. The study was published in the online journal Nature Communications, prior to its publication in the printed version of the journal.

Doctors Richard Gatti & Peiyee Lee are the leaders of the study. Their team managed to harvest iPSCs and use them to create the disease-in-a-dish model of the disorder known as ataxia telangiectasia. This technique uses the ability of the stem cells to regenerate and differentiate in a Petri dish. Basically, this allows researchers to study the disease in the laboratory, being able to test various drugs on the cells.

Ataxia telangiectasia (A-T), a disease also known as the Louis-Bar syndrome, is a neurodegenerative disease that  causes severe disability for patients. The word “ataxia” refers to the poor muscular coordination, whilst the word “telangiectasia” refers to the small dilated blood vessels found near the mucous membranes or the skin of the patient. Both of these symptoms are pathognomonic signs for the disease. The parts of the organism that are most likely to be affected are the brain and the immune system. Ataxia telangiectasia also affects the DNA, inhibiting its repairing capability, thus increasing the risk for the onset of cancer. The loss of function in the cerebellum leads to the difficulties in muscular coordination and movement. Due to their weakened immune system, patients with A-T are most likely to suffer from frequent infections.

Neurodegeneration

The gene responsible for the disease, named ATM (ataxia telangiectasia mutated), is found on the long arm of chromosome 11 and is responsible for the repairing of damaged DNA. The development of a disease-in-a-dish model of the disease was critical due to the fact that the disease is different in laboratory animals and humans. The animal models of the disease do not suffer from cerebellum damage, thus the coordination and movement difficulties cannot be studied. The newly developed model also allows researchers to test new drugs.

Professor Lee and his colleagues used the iPSCs to create neural cells that were developed from the skin cells of patients with specific types of genetic mutations. In their lab tests, scientists managed to model the cell’s incapability to repair the damaged DNA due to the absence of the ATM proteins. The disease-in-a-dish model also allowed the research team to test SMRT (small molecule read-through), a new drug that would increase the activity of the ATM protein. According to professor Lee, patients who show even the slightest activity of the ATM protein suffer from a less severe form of the disease. “This makes our discovery promising, because even a small increase in the ATM activity induced by the SMRT drug can potentially translate to positive effects for patients, slowing disease progression and hopefully improving their quality of life”, Lee added.

The results of the study reveal that the tested SMRT drug could have a beneficial effect on A-T patients, through the improvement of the function of their immune system. Moreover, the iPSCs that were combined with the SMRT drug might be invaluable for identifying and understanding the onset and progression of A-T. The research team suggests that the SMRT drug could be effective against other neurodegenerative disorders as well.