Image shows an intestine cell under a microscope

MS and the brain-gut connection

Dr Peter Connick is a neurologist at Edinburgh University. Our Research Network member Pam Ward spoke to him about why a hidden community of bacteria living in our gut may hold the key to treating MS.

Why is a neurologist interested in the digestive system?

Over the past decade or so, we've begun to appreciate how much communication there is between the brain and the gut. They're in contact all the time.

On top of this, there's the gut microbiome, which is what we call all the bacteria, fungi and other microbes that live in our digestive system.

It's strange to think about, but there are actually more bacterial cells inside the human body than human cells! These bacteria can change how our bodies work, including our immune systems and brains.

What has microbiome research told us about MS?

To prevent MS, we need to understand what causes it. 50 years of research has taught us that genes and environment and lifestyle factors like vitamin D, smoking and infections are important, but not the whole story.

We think the gut microbiome might have a role by triggering or ramping up the immune system's faulty response in MS.

Recent experiments suggest that this is an important area to explore. An important study from 2017 found that mice who received gut bacteria from people with MS were more likely to develop an MS-like condition than mice given bacteria from people who don’t have MS. You can read the full paper about MS and microbiomes in mice on the National Academy of Sciences USA website.

What's the International MS Microbiome Study?

We're now looking at how the bacteria inside us influence the development of conditions like MS. We don’t know if it’s one or two bacteria causing the problem in MS, or whether it's the balance of types of bacteria that’s important. We hope to answer this by looking at the diet, genetic makeup and microbiomes of a large number of people.

The International MS Microbiome Study is recruiting 4,000 people with or without MS from across the world. We're looking for pairs of people who live together - one with MS and one who doesn't have MS.

If you’re interested in taking part, download our information leaflet from the Anne Rowling Clinic website.

Or find out more about the International MS Microbiome Study on their website

Could microbiome research lead to MS treatments?

The next challenge we’ll have is working out how to fix any imbalance of bacteria. We all change our bacteria populations when we switch diet or take antibiotics. But these changes are not precise. So if our studies identify bacteria that might be important, we'll probably need to go back to animal research to confirm exactly what that bacteria does.

I’m often asked whether a specific diet could help. But testing diets is complicated and most studies so far have been quite small, so we don’t have a clear answer yet. While we don’t know if there's an ideal MS diet, we know you don’t want to have another condition on top of your MS. So a healthy diet that looks after your heart and the rest of your body is definitely important.

This blog first appeared as an article in Research Matters magazine. To get Research Matters by post please contact supportercare@mssociety.org.uk about subscription. You can also download the full issue for free.