Israeli researchers announced Tuesday that they have uncovered a key mechanism that causes the neurodegenerative disease ALS, which may unlock a way to delay or reverse the condition which affects thousands of people annually.
The team from Tel Aviv University, along with researchers from Sheba Medical Center and from institutes in Germany, France, the UK and US, found that a buildup of a protein called TDP-43 near neuromuscular junctions, which translates neural signals into motor activity, causes motor neurons to degenerate and die by inhibiting mitochondrial production.
This in turn leads to amyotrophic lateral sclerosis, also known as Lou Gehrig’s Disease, which causes sufferers to lose the ability to walk, talk or even breathe.
“The paralysis caused by the disease results from damage to the motor neurons, which leads to the degeneration nerve endings and to the loss of muscle innervation,” Prof. Eran Perlson, who led the study with doctoral students Topaz Altman and Ariel Ionescu, said in a news release.
“This consequently leads to the degeneration of the nerve and the death of motor neurons in the spinal cord, however until now we could not understand the basic biological mechanism causing the initial damage behind this vicious cascade.”
By using an experimental molecule to break down TDP-43 in animals, the scientists were able to restore motor neuron activity, opening the door for possible drugs that can cure ALS in humans if found before the damage becomes too severe, the researchers said.
“This discovery can lead to the development of new therapies that could either dissolve the TDP-43 protein condensates or increase the production of proteins essential to mitochondrial function, and thereby heal the nerve cells before the irreversible damage that occurs in the spinal cord,” Perlson said.
ALS, which famously afflicted Stephen Hawking and was the subject of the Ice Bucket Challenge, has no approved drug treatment.
“We are tackling the problem on the other end — in the neuromuscular junction. And if in the future we could diagnose and intervene early enough, maybe it will be possible to inhibit the destructive degeneration in ALS patients’ muscles,” he said.
The peer-reviewed study was published in the journal Nature Communications.