What is MND?
Motor neuron disease (MND) is a progressive neurological disorder which causes muscle weakness and wasting. MND is an umbrella term which encapsulates a few different diseases, but the most common type of MND is ‘Amyotrophic lateral sclerosis’ (ALS). The exact cause of ALS is unknown, however it is understood that genetics and environment play a role in the development of the disease. ALS occurs when the cells which are mainly responsible for movement, known as ‘motor neurons’, dysfunction and begin to weaken or die away. This may not initially strike you as disastrous, but unfortunately, ALS causes the muscles responsible for breathing and swallowing to also weaken, and this is why ALS is usually a terminal disease. Why these cells dysfunction has yet to be fully elucidated, however, research has shown that these cells exhibit altered metabolism (the way in which these cells use energy), increased excitation (this means that the cells are ‘turned on’ too much or too quickly relative to a healthy individual) and increased cellular toxins (these are not the same toxins available in the external environment, they are a build-up of the natural by-products produced by the cells), as well as many other reasons. About 10% of cases are associated with genetic mutations.
What do we do?
We provide the only specialist multidisciplinary clinic for motor neurone disease in Ireland. Patients who are referred to the clinic are seen within 2 weeks of receipt of referral. Over the past 27 years, we have cared for over 2800 people with MND, and have been actively engaged in research into identifying the causes and finding effective treatments for this condition. Our clinic offers a well-rounded approach for care including physiotherapy, nutritional advice and occupational therapy. We offer voice banking for MND patients who begin to find speaking difficult, genetic screening, and support for carers, as well as opportunities to partake in clinical trials for suitable patients. Our team is also on the forefront of MND research, and are actively investigating several areas associated with the condition, including motor network dysfunction, respiratory function, neuropharmacology, neuropsychology and genetics.
What is the prevalence of MND?
The incidence of MND is 1 in 30,000. We established a database of people with MND in the Republic of Ireland in 1994 with the aim is to capture everybody with the condition, to learn about how frequently the condition occurs in Ireland, and to identify people with other conditions who were misdiagnosed with ALS. We have found that approximately 140 people in the Republic of Ireland develop MND annually, and that there are around 400 people affected by the condition at any time.
What causes MND?
There are probably a variety of different causes of MND. It is likely that some people have a genetic susceptibility to developing the condition, and that environmental factors can interact with these genetic risks. These factors combine to affect the function of motor neurones. Although there has been a lot of research into possible environmental factors, no conclusive causes have been identified.
Many groups around the world are investigating the potential causes of MND. Once this is well established, it will be easier to find treatments and cures. This is why research is such a big part of our groups work.
Sometimes, scientific findings may seem counterintuitive. For example, our group has recently found a link between MND and individuals who are more inclined to participate in sporting activities. It is this counterintuitively that highlights the importance of research.
Now, we and other groups are interested in exercise as a risk-factor for developing MND, and we suspect that a lifetime background of intense exercise may slightly increase the risk of developing MND in some individuals. Our preliminary findings support this hypothesis, and a large European study is planned to establish whether this is truly the case.
Does MND run in families?
MND can run in some families, but this happens only in approximately 10% of patients. In the remaining 90% of cases, the disease occurs sporadically. Many groups have looked for genes causing familial MND, and so far we know of at least 5 genes that can cause MND. The commonest by far is the gene SOD1, which accounts for 20% of familial MND in the United States. Despite this however, SOD1 mutations are rare in the Irish population. We have been looking for genes that might increase the risk of developing MND in non-familial MND, and our group has successfully found another important gene in about 1% of the population that can cause both familial and non-familial MND. This gene is called ANG, and makes a protein called angiogenin which is responsible for aiding in the formation of vasculature in the brain. Mutations in ANG seem to be most common in Irish and Scottish populations, but are still quite rare even in these populations. However, our discovery has shown that angiogenin is an important protein within the nervous system, and this has opened up a new direction in research that is likely to lead to the development of new approaches towards treatment.
Is dementia a feature of MND?
Recent research has established that over 60% of people with ALS develop some changes in the way they think (cognition) or behave, with approximately 13% of people with ALS developing dementia. The type of dementia associated with ALS is called frontotemporal dementia, which affects the front parts of your brain and is often associated with behavioural changes. These changes can present challenges for both the patients and carers. To date, the Irish research group has worked on examining the nature and extent of these cognitive and behavioural changes, and has succeeded in identifying the subgroups of patients for whom they are an issue. Click here to read more about Neuropsychology in our current research section.
Does quality of life decline as MND progresses?
Our group believes that that a central tenet of managing MND is to preserve and enhance quality of life (Qol). Quality of life is difficult to measure, as most scales use “health” as one of the areas of measurement. We therefore measured individualized quality of life in MND, using the SEIQoL, designed by our collaborators at the Royal College of Surgeons in Dublin. In SEIQoL, patients nominate what is important to them. Our work has shown that although health related quality of life declines as the disease progresses, individualized quality of life, as measured by SEIQoL, does not. This is an important observation in assessing the impact of health care initiatives.
What is the standard of care for MND?
Our group was the first to conclusively demonstrate that multidisciplinary clinics for MND confer a survival advantage, independent of other factors. This is a very important finding for public health services and health planning. Our work has since been replicated in other countries.
The following are potential treatments you may come across for MND and the reasons why we currently don’t feel that they are beneficial. Further information on evidence for particular treatments can be found on the ALS Untangled website by clicking here.
CBD has become a popular alternative treatment in recent years. CBD, or cannabidiol, is one of the active compounds in cannabis. CBD is often touted as a treatment for many diseases, from cancer to arthritis and indeed, MND. There has been much anecdotal evidence for CBD improving symptoms of some inflammatory diseases like arthritis, but this has been on a case by case basis and there is little scientific evidence to support these anecdotes. Currently, there is no evidence that CBD improves MND symptoms. Furthermore, something patients should be aware of is that CBD is an unregulated substance in Europe, so there are no laws stating that suppliers must include a certain percentage of the pure substance in the product they are selling. This is a double-edged sword as it means that you could be receiving a product with very little or no CBD despite paying for it, or a product that has very high quantities of CBD which could potentially be dangerous. Some studies have reported that cannabis can improve spasticity in patients but the evidence for this is weak and our clinic offers approved treatments for spasticity, such as botox. Moreover, studies have reported that CDB can cause respiratory depression in populations with laboured breathing, so taking unregulated amounts of CBD can potentially be dangerous for MND patients.
Why is it unlikely that CBD can treat MND?
Many labs around the world are researching CBD and its effects. What is known so far is that CBD has two receptors in the body, CB1 and CB2. Receptors act like a lock on the surface of cells, and only the right key-CBD molecules in this case-can open the lock and allow the cell to react to the substance. These CBD receptors are present throughout the body, not just in brain cells, so taking CBD can affect multiple cell types in your body, from your kidney cells to your stomach cells. So far, research has shown that CBD has an effect on cells but usually, these effects are only minor and don’t have the capacity to improve the users’ overall health. However, these minor effects in conjunction with underlying pathology, such as the laboured breathing mentioned above, can have negative effects on the user.
Is stem cell therapy effective for MND?
Stem cells are undifferentiated cells. In other words, they are unspecialised cells, which means that they have yet to commit to a specific cell type. This allows scientists the opportunity to drive these cells to develop into any cell they desire by using ‘transcription factors’. Transcription factors are proteins which essentially ‘turn on’ the necessary genes to push the cells towards the desired cell type. Although stem cells harbour powerful potential for therapy in the future, they currently are not being used to treat MND as many aspects of stem cell therapy have yet to be fully understood. For example, scientists are able to grow motor neurones using stem cells, however, they are currently unable to differentiate the stem cells into upper and lower motor neurones. Seeing as both types of neurones are affected in ALS, and both types differ in their function, it is important to be able to manipulate stem cells with a high degree of precision prior to using them as therapy. Stem cells also have strong potential for modelling disease in the lab in order to further progress our understanding of ALS.
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