Zebrafish show that ‘connector neurons’ are the key in early stages of MND

A recent study by Motor Neurone Disease Association-funded researcher Dr Tennore Ramesh from the Sheffield Institute for Translational Neuroscience (SITraN) has shown that even before the symptoms of MND occur, at the earliest stages of the disease, ‘connector neurones’ known as interneurons are already becoming damaged in the zebrafish.

Dr Tennore Ramesh
Dr Tennore Ramesh

Zebrafish are ideal models for helping scientists understand what happens in MND. Unlike mice and fly models, zebrafish have transparent embryos which enable scientists to get a unique view of the developing neurones under a microscope! Scientists can also look at disease progression in adult zebrafish by looking at muscle strength and measuring their progress swimming against a current.

Not only are zebrafish useful for helping scientists understand what happens in MND, they are also an ideal drug screening model. Zebrafish and humans are more similar than you may think (see Kelly’s post) and potential new MND drugs can be screened quickly. Looking at how MND progresses in the zebrafish, before symptoms appear, can help us gain a better understanding of what causes the disease.

Motorways, dual carriage ways and slip roads

No, I’m not writing about travel alerts or the latest road disruptions due to flooding or snow. In fact, these road systems happen to be a perfect example of what interneurons are, how they relate to motor neurones and what goes wrong in MND.

Our body consists of two types of motor neurones, which are known as upper and lower motor neurones. The upper motor neurones are found in the motor region of our brain and connect to the spinal cord. The lower motor neurones are found between the upper motor neurones in the spinal cord and connect to the muscles (e.g. in the arms and legs). Interneurons are the vital connections between the upper and lower motor neurones.

Interneurons are the 'slip roads' between upper and lower motor neurons
Interneurons are the ‘slip roads’ between upper and lower motor neurons

When a signal is sent from our brain to bend an arm it starts by travelling down an upper motor neurone. The signal then travels to a lower motor neurone via an interneuron. When the signal from the lower motor neurone reaches the muscle in our arm it causes the muscle to contract and bend.

In MND these upper and lower motor neurones become damaged and they are unable to transport the nerve signal from the brain to the muscle in our arm. This means we are unable to contract and bend, even though the brain is telling it to.

­­­In our road system scenario the upper motor neurones are the motorways (e.g. the M1), and the lower motor neurones are the dual carriageways that link the motorways to nearby towns (e.g. the A38). In order for an upper motor neurone to send a signal (e.g. a car) to a lower motor neurone it needs to go via an interneuron, which in our road system scenario is a ‘slip road’ – making these interneurons vital connections between motor neurones.

This study has given us a better understanding of what happens in MND at the early stages of the disease (before symptoms occur). The researchers found that interneurons became damaged before the motor neurones themselves. Therefore this shows that interneurons are important in the early stages of the disease and scientists can begin to look at ways of preventing interneuron damage to see whether this has an effect on MND.

Adding more evidence to the puzzle

This study showed that, in zebrafish, interneurons are involved in the early stages of MND, which adds further evidence to previous work by another MND Association-funded researcher. Dr. Martin Turner (Oxford) also found damaged interneurons at the early stages of the disease before symptoms of MND occur in humans, with other studies showing interneuron damage in SOD1 mice models.

The next step would be to look at ways of preventing these interneurons from becoming damaged, to see whether this has any effect on the progression of MND.

This research is the first article we have paid to be made available Open Access, so that it is freely accessible to all. The article was published online in the prestigious journal ANNALS of Neurology on the 31 December 2012.

Paper reference:

McGown, A. et al. Early Interneuron Dysfunction in ALS: Insights from a mutant sod1 Zebrafish Model. ANNALS of Neurology 2012 DOI: 10.1002/ana.23780 http://onlinelibrary.wiley.com/doi/10.1002/ana.23780/abstract

Vive la difference!

It could be easy to assume that one motor neurone is pretty much like another, but a series of presentations on Thursday clearly showed that we need to be a little more sophisticated in our thinking.

Dr Hynek Wichterle (Columbia University) discussed how in the developing embryo, there are distinct regional subtypes of motor neurones in the spinal cord. For example, the motor neurones at the bottom of the spine can be easily distinguished from those at the top of the spine by the pattern of genes that are switched on and off – in a nutshell, different motor neurones have their own regional ‘postcode’.

Dr Wichterle went on to show that you can generate motor neurones with specific postcodes  in the lab, from embryonic stem cells . Having motor neurones  that  hopefully reflect different aspects of MND will allow researchers to better understand the subtleties of motor neurone function and develop more relevant treatment approaches.

It’s well known that some motor neurones are particularly resistant to the disease, such as the so called ‘oculomotor neurones’ that control eye movements. By looking at  the pattern of genes  being switched on and off in early mouse embryonic development, Dr Wichterle was able to induce the same pattern in mouse stem cells to create what look very much like oculomotor neurones in the dish. There is some further work to be done to check that they are indeed what he thinks they are, but they could be a very important tool in helping to understand why some motor neurones are tougher than others.

Continuing the theme, Dr Georg Haase  (Marseille) introduced an elegant way of separating different populations of motor neurones from mouse spinal cord. He focused on two subtypes of motor neurone – those that connect to the limb muscles  and those that connect to the main trunk of the body. After they are separated out, they can be grown in culture (in a dish in the lab) . He then showed that these two different subtypes of motor neurone acted very differently in their response to chemicals known as neurotrophic factors . The word neurotrophic can be literally translated as ‘nerve nourishing’ and these chemical compounds have attracted a lot of attention in the past as possible therapies for MND, with a couple being tested in large clinical trials . Unfortunately these trials have not shown any effect, but this could be because  – as Dr Haase showed in his lab studies – each neurotrophic factor only acts on a proportion of motor neurones. He suggested that the different ‘survival profiles’ he sees in his cellular studies  provide a rationale for selecting combinations of different neurotrophic factors for further testing in mice – and hopefully in man.

Prof Pam Shaw (University of Sheffield) also asked the question of what makes  oculomotor neurones  different, but her presentation took us from mouse to man. Using a technique called laser capture microdissection, which allows individual motor neurones to be removed from post mortem spinal cord tissue form MND patients, she and her colleagues are able to examine which genes  were switched on and off in the cells. Research like this requires very high quality tissue, removed shortly after death, but Sheffield happens to host one of the best MND tissue banks in the country.

She compared these ‘gene expression patterns’ in the disease-resistant oculomotor neurones with the more vulnerable motor neurones  from the lower spinal cord. There were  considerable differences in the patterns, with a much larger number of genes being switched on in the oculomotor neruones. Many of these genes could be dividied into functional families, which act on a similar biological pathway. Key protective processes activated included neurotransmission, mitochondrial function and proteasomal function – all of which are strongly implicated in MND. If human oculomotor neurones  survive by gearing up these  protective pathways, it provides possibilities that drugs can be found which act in the same way.

Our International Symposium website news stories:

International Symposium closes in Chicago

International Symposium focuses on clinical trials

International Symposium focuses on carer and family support

International Symposium begins in Chicago

Researchers unite at our International Symposium on MND

After you’ve finished reading the symposium articles that interest you, we’d be grateful if you could spare a few minutes to fill in our short online survey on our symposium reporting. Your comments really are useful and allow us to continually improve our symposium reporting. surveymonkey.com/s/alssymp 

University of Bath research shows how angiogenin affects motor neurone survival

Published in the prestigious journal Nature Communications and funded by the Wellcome Trust, University of Bath researchers looked closely at the structure of 11 mutated angiogenin proteins, and how changes in their structure influenced activity, function and survival in motor neurones.

Dr Brian Dickie, Director of Research at the Association, said “The researchers at the University of Bath have skilfully combined aspects of biology, chemistry and physics to answer some fundamental questions on how angiogenin can damage motor neurones. It not only advances our understanding of the disease, but may also give rise to new ideas on treatment development.”

Mutated forms of the gene editing protein, angiogenin, are known to cause MND in some families affected by the inherited form of the disease. This is due to a mutation in the normal angiogenin gene (a mistake in the instructions for making the protein) that leads to the production of a faulty/mutated angiogenin protein.

This new research expands on our knowledge of angiogenin, as back in June this year angiogenin, was identified by Irish researchers as playing a vital role in motor neurones with the effects tested in a mouse model of MND.

Creating images with x-rays

University of Bath researchers used a technique known as x-ray crystallography (a method that uses x-ray light to produce highly detailed images of the structure of a protein). Using this technique they were able to view the structure of angiogenin, and 11 angiogenin MND mutants, in exquisite detail. Specifically the researchers looked at the active site (where all the action happens) for changes that may affect the function and activity of the mutated proteins.

These x-ray crystallography images show stunning structural differences in the angiogenin MND mutant proteins, particularly around the active site, and the researchers found that these structural changes caused the mutated angiogenin proteins to have varying levels of activity.

Dr Vasanta Subramanian, who was involved in the research, said: “We hope that the scientific community can use this knowledge to help design more drugs that will bind selectively to the defective protein to protect the body from its damaging effects.”

An MND Association funded study has also used this technique of x-ray crystallography to look at the structure of mutant SOD1 proteins, which are another cause of inherited MND. Under the leadership of Prof Samar Hasnain, Dr Neil Kershaw is also one step ahead and is examining potential drugs to ‘mend’ these abnormal SOD1 proteins. This shows how this type of research, investigating structure and activity of the mutated proteins, can influence the development of new drugs.

What happens to angiogenin in the cell?

As well as changes in the activity of the protein the structural changes cause the angiogenin MND mutants to lose their function, leaving a protein sitting around in the cell, unable to do anything! The researchers found that it is essential that angiogenin is transported from the cytoplasm to the nucleus of the cell in order for the protein to function properly. This is an important step during the process in which proteins are made, if this does not occur then the protein will not function properly. In the angiogenin MND mutant proteins this does not occur correctly with either none, or very little, angiogenin being transported to the cell nucleus. This means that the angiogenin MND mutant proteins do not function properly compared to the normal angiogenin protein.

Stress Granules

The University of Bath researchers also found that the angiogenin MND mutant proteins prevented the motor neurones from producing ‘stress granules’. These are little packages that appear when a neurone is under stress, such as when low oxygen levels occur. When this stress factor occurs they release their contents to protect the motor neurone from damage.

These stress granules are the motor neurones natural defence mechanism. Without these granules the cell’s natural defences are lost and this influences the survival of the cell.

In Summary

This research gives us an important insight into how MND mutations affect the normal structure and function of angiogenin in motor neurones in some inherited forms of the disease. This not only advances our understanding of the disease, but may give rise to new ideas on treatment development in the future.

University of Bath press release

Journal article

Research we fund

Attracting Promising Research – Calling for Project Grant Applications

Autumn is fast approaching which means it’s time to open our online summary application form for our next round of research grant applications.

This round is for project grant applications. The deadline for summary applications is Friday 2 November 2012.

Reaching out for researchers

We currently fund ground breaking projects in a number of would class research institutes in Edinburgh, London, Oxford, Sheffield, Cardiff and New York, among others. This flexible approach allows us to fund the best and most promising research regardless of geographical location.

Good researchers are fundamental to good research and developing the MND research workforce, nationally and internationally, is a key element of our Research Strategy.

Getting the best of the best

As with all of the research projects funded by the MND Association, our rigorous application process allows us to ensure we only fund projects of the highest quality and of direct relevance to MND.

The way that we fund research starts with a summary application, which is a concise outline of the proposed project. After the deadline date has passed a decision is made as to whether the summary is relevant to MND and that the project will help us to move toward the aims set out in our Research Strategy. If the summary doesn’t fit, it’s rejected. If all criteria are met, the summary is reviewed by our Biomedical Research Advisory Panel (BRAP).

The reviewer’s comments and scores are then assessed using a two thirds majority rule. Each reviewer scores the summary application. A score under 50 is classed as unsuitable for funding, if it’s over 50 then the applicant is invited to submit a full application.

We hope this year holds yet another exciting round of project grant applications!

More information:

Apply now for an MND Association research project grant.

Find out  how we fund research.

Find out what research we fund.

Tuesday evening – the night before Symposium

At 6pm this evening, there was a real air of anticipation at the conference hotel. On level 2 the poster presenters were gradually finding their allocated slots and gaps were being filled. Up the escalator on level 3, the registration desk has now closed for the night. It will open again at 6am in the morning, ready to register another few hundred delegates. The lanyards are neatly rolled, the bags stacked tidy and ready for their eager recipients. A snake of coffee cups is ready for that all-important mid-morning energy boost.

Getting into the lift is like entering a who’s who of the MND world, international scientists and clinicians greeting each other and exchanging stories on jet lag, holiday plans and of course the results from their lab or scientific gossip.

As well as soaking up this atmosphere, today I’ve been busy putting Kate and Kelly’s plans for the poster session into action. The poster session is arguably the most interactive part of the meeting, an opportunity to share a hard copy of your presentation with a (possible) 600 people is valuable. They may pass on the next tips to helping get that experiment to work or you may set up a new collaboration or redirect your research. However, in order for this all to happen, 300-ish 2m high and 1m wide boards, need to be individually assigned to specific posters, in an order that (I hope) the delegates will follow. Thanks to Harriet for all her help with sorting this out.

Across the road from the hotel is the Queen Victoria Building shopping arcade. It is beautifully decorated for Christmas – there are only a few weeks to go. But for Symposium delegates it is only one more sleep before our excitement begins!

X-cell stem cell centre has been investigated by ALS Untangled

With the internet providing an expanse of ‘quackery’ jumbled up with facts, it’s becoming increasingly difficult for anybody to know what source of information can be trusted. This issue is especially apparent to us when we add unproven treatments into the mix. An unproven treatment is, quite literally, a treatment that has no reliable proof for its benefit as a treatment.

As a bit of background, the only way that a treatment can be moved from being ‘unproven’ to ‘proven’ is by conducting a series of controlled clinical trials that can confirm that it is more effective at treating something than a ‘dummy drug’ – called a placebo. This may seem a bit bureaucratic and time consuming but it is a necessary step in finding a truly beneficial treatment for any disease or ailment. Until a treatment has proven itself to be effective, it remains unproven.

So, to shine some light on the clouded situation of where the facts lie within unproven treatments advertised over the internet, a group of international researchers, collectively known as ALSUntangled (ALSU) was set up. ALSU’s most recent investigation was into a stem cell treatment that is provided by a German clinic called ‘X-Cell Stem Cell Centre’.

The X-cell centre is a clinic based in Germany that injects a person’s own stem cells – extracted from their bone marrow, back into them and claims that it can treat MND (as well as a large number of other conditions). To-date, no such stem cell treatment has undergone any clinical trials that have demonstrated their safety and effectiveness. The use of stem cells as a treatment is therefore regarded as an unproven.

ALSU therefore set out to find out if there was any truth behind the X-Cell Centre by investigating:

  •  The procedure that they adopt is scientifically sound
  • The progression and opinions of three people who went to the X-Cell Centre.

From this, ALSU concluded that the data provided on the X-cell website is flawed and suggest either its removal, or for them to add a disclaimer to alert readers to its flaws. From the small number of people they followed, none showed signs of improvement. ALSU therefore concluded that until they demonstrate the safety and effectiveness through a rigorous clinical trial that they would not condone X-Cell centre’s protocol for people living with MND.

ALSU have published these results in a free to read article in the Journal ‘ALS’, which is written in an accessible way. ALSU also have a twitter page where people can suggest unproven treatments that they should investigate. More information on stem cells as a treatment for MND can be found on the stem cell pages of our website.

ALSU are not alone in their endeavour, as within the research development team a number of us (Brian, Belinda, Kate and I) are able to make sense of the claims of unproven treatments for MND. We provide people with the facts so that people affected by MND can make up their own minds about whether it’s an option they would like to consider.

If you are considering an unproven treatment and would like to know the facts about the information they provide, please contact us at research@mndassociation.org.

*update – The X-Cell centre has now been closed down by the German Government due to a loophole in law being tightened.