Motor neurone disease – helping nerves to fight back

About 1,500 people are diagnosed with motor neurone disease each year in the UK.(1,2) Many die within just five years, after progressively losing control of their movement, speech, swallowing and breathing. There is no cure. Researchers are investigating how nerve cells try to recover from the destruction caused by this cruel disease, in the hope of identifying possible future treatments.

What's the problem and who does it affect?

A relentless deterioration

Every day, around four people in the UK are diagnosed with motor neurone disease.(1) This incurable illness can strike anyone, of any age, though most sufferers are over 50. The initial symptoms are mild – including stumbling, a poor grip, difficulties swallowing or slurred speech. But the diagnosis brings shocking news.

Most sufferers die within two to five years, after experiencing an unremitting deterioration in their state of health. They gradually become paralysed, losing control of their arms and legs, and have to use a wheelchair. Many have difficulties swallowing and have to be fed through a tube. They are also likely to need help with breathing.

Everyday activities, such as bathing and communicating, can be made easier by help from specialists, like occupational therapists, and equipment, such as hoists and computer-based aids. But sufferers become increasingly dependent on carers – often partners or children. While this can be traumatic, it can also strengthen the bonds between family members, as they make the most of precious time together

What is the project trying to achieve?

Nerves fight back

The symptoms of motor neurone disease result from the death of certain nerve cells in the brain and spinal cord. These nerve cells, called motor neurones, send messages from the brain to the muscles, telling muscles what to do.

In most cases, the cause of the motor neurone damage remains a mystery. Degeneration within a group of motor neurones is progressive, so that while some cells may be dying, others survive, remaining, as yet, unaffected. Researchers are helping to increase our understanding of the disease process, by studying two opposing phemonena:

1. They are investigating how surviving motor neurones attempt to compensate for the death of neighbouring motor neurones. Mounting evidence suggests surviving nerve cells try to re-establish the lines of communication by forming new connections, called synapses, with other nerve cells and with muscles. Researchers are investigating this process in more detail, and hope to find ways to encourage it using drug therapy.
   
2. The team is also studying how the disease process leads to the production of substances that discourage surviving nerve cells from making new connections. Researchers are trying to find ways to block the action of these substances using drugs that are already undergoing laboratory tests for potential use in spinal cord injury and multiple sclerosis.

What are the researchers' credentials?

The project leader, Dr Anthony Pullen, has recently led studies, funded by charities including Action Medical Research, that revealed the toxic properties of antibodies and enzymes in the blood of people with motor neurone disease. He has also led successful investigations into the reorganisation of nerve cells following spinal cord injury, and has an excellent reputation in this field.

The studies will take place in a laboratory within the Sobell Department of Motor Neuroscience and Movement Disorders, which specialises in both basic and clinical research into a variety of movement disorders, including motor neurone disease. The department has an international standing for excellence in research.

Who stands to benefit from this research and how?

Gathering vital new information

The researchers stress that their work is in its early stages. But they are gathering vital new information, which they hope will be of key use to the research community as they strive to find new treatments for motor neurone disease.

The team hopes to find out more about the natural processes that nerve cells use as they try to overcome the damage caused by motor neurone disease. They hope to identify potential new treatments that might encourage these processes.

In the future, it’s possible these treatments could be used, alongside others, to slow the progression of motor neurone disease or reduce the damage it causes. The ultimate goal is to reduce the suffering of people with this distressing illness, and increase their life expectancy, allowing them to retain their independence and their quality of life for longer.

For people with motor neurone disease, and their families, who must currently face up to the illness with no available cure, any progress in treatment would be very welcome indeed.

References

1. Bruijn LI, Miller TM, Cleveland DW. Unraveling the mechanisms involved in Motor Neuron Degeneration in ALS. Annual Review Neuroscience 2004;27:723-749.
2. Leigh PN, Swash M. Motor Neurone Disease: Biology and Management. London, Springer-Verlag, 1995, 1st Edition, ISBN: 3 540 19685 4; 0 387 19685 4.