A probiotic for Parkinson’s?

Researchers at the International Parkinson’s Centre of Excellence at King’s College Hospital NHS Foundation Trust, led by Prof K. R. Chaudhuri, are about to embark on a study that may potentially change the way we treat Parkinson’s.

Today, Parkinson’s is treated using medications that mask the problems happening in the brain. These medications — which aim to replace or mimic the effect of the chemical messenger dopamine — can be very effective at addressing some of the motor symptoms of Parkinson’s, particularly in the early stages. But they are often less effective for the non-motor symptoms like pain, anxiety, and constipation.

Now, a world-first UK-led clinical trial is due to begin to test if a probiotic drink could help improve both the motor and non-motor symptoms of Parkinson’s by improving gut health.

A problem with the gut

New research is helping us to better understand what causes these symptoms and moving towards new and better treatments. Some of the latest research has focused on the role of the gut in Parkinson’s (indeed, this budding area of research has recently been featured in another blog post — “Could your gut be affecting your health?”). And recent studies have shown that the microbes that live in our guts, called the gut microbiota, can be altered in people with Parkinson’s.

Much of the research into what constitutes a healthy gut microbiota has focused on bacteria. And we still don’t fully understand which species of bacteria are good (or bad), which is why researcher Dr Doitsidou and her team are systematically studying the various types of bacteria to identify those key few that play an important role in Parkinson’s. But evidence is pointing towards several species of potentially protective bacteria being missing in people with Parkinson’s.

A healthy gut and Parkinson’s

Our guts play an important role in absorbing nutrients while keeping out nasty pathogens and protecting us from absorbing other toxins. Good bacteria are important for maintaining the effectiveness of this barrier and our overall gut health. But changes in the types of bacteria living in our gut could lead to a syndrome known as ‘leaky-gut’ — where tiny holes form that may allow material, and potential toxins, to leak through the gut wall into the blood.

So why is this important in Parkinson’s? Well, gut problems are common in Parkinson’s and researchers have recently discovered that in abnormal clumps of protein, called Lewy bodies, that can be found in gut nervous system and are believed to spread from there to the brain via the vagus nerve. Exactly how and why the clumps start to form is still much of a mystery, but some of the latest research is highlighting the importance of a healthy gut. So rebuilding a healthy community of bacteria in the gut, in theory, may help to protect against Parkinson’s and help to combat symptoms.

The pros of probiotics

One strategy to try and reintroduce good bacteria is to use a treatment called faecal transplantation. This involves collecting bacteria that live in the gut of a healthy donor from a stool sample, and preparing and transplanting them via a tube directly into the gut of the recipient. But while this may work for some conditions where the gut microbiota is abnormal, the process is difficult and still needs regulatory approval and safety checks before it could be made available more widely. So, researchers have been investigating other ways to get good bacteria back into the gut.

A faecal transplant may provide a more direct route for live bacteria to reach the gut but what about oral probiotics? Unfortunately, the bacteria in many commercial probiotics are unlikely to reach the lower gut, where they are needed, as most types of bacteria are wiped out on route by the acidic environment in the stomach. However, with the right combination of good bacteria and delivery mechanism, this may not be inevitable.

A new type of probiotic

Symprove is an oral drinkable probiotic that claims to be able to deliver live bacteria to the lower gut and it has a rather interesting backstory with roots in the farmyard.

Back in 1986, Barry Smith, an ex-military nurse, was concerned about what might be in the food he was giving his animals, and how antibiotics might be wiping out good bacteria and affecting their health. His solution was to developed a clean food of germinated grain that he laced with live bacteria to help support a balanced and healthy gut in his animals.

While initially, people were skeptical about his practices, in time they drew the attention of local vets who noticed Barry’s livestock were healthier and less prone to infection. Interested in if this bacteria-rich food could have wider applications, vets carried out early studies with 100 cats and dogs diagnosed with colitis, a condition where parts of the gut become inflammed. When the food achieved a 95% clear up rate, it encouraged Barry to take his probiotic forward to see if it could also benefit people.

Today, the solution has been refined greatly since those early days and Symprove is now a unique multi-strain liquid probiotic that aims to get beneficial bacteria through the acidic stomach intact so they can reach and thrive in the gut and so help improve gut health. It does this as it is mostly water, which the Symprove team says avoids triggering digestion that could kill the bacteria in other types of probiotic.

Results from placebo-controlled clinical trials carried out at King’s College Hospital have suggested the probiotic may have beneficial properties for both irritable bowel syndrome and diverticular disease — a condition that causes abdominal pain. And now researchers want to test if it could be beneficial for people with Parkinson’s with gastrointestinal problems in a pilot trial.

However, this won’t be the first probiotic study for people with Parkinson’s as one previous study has demonstrated daily probiotics may improve in bowel movements after 4 weeks. But what is different is that it may help with more than just gut problems.

Professor K Ray Chaudhuri explains more about this new study:

“From our experience at the Parkinson’s Centre at King’s College Hospital some people with Parkinson’s have shown a considerable improvement in motor and non-motor aspects after taking Symprove for extended periods.

“The rationale behind this observation may rest with Symprove induced improvement in gut microbiota. However, there are no studies which have addressed a possible beneficial effect of Symprove in a controlled study.

“If successful, this simple management strategy may have a major impact for people with Parkinson’s.”

Gold standard clinical trial

The team have designed a randomised, double-blind, placebo-controlled trial — the gold standard for testing if treatments actually work. Neither the participants or the researchers will know who will be taking the real Symprove treatment and who will be in the placebo group, which is important to avoid any subconscious bias. And, as there is a placebo group in the study, the results should be able to show if the treatment has a greater effect than the placebo effect.

You can read more about the placebo effect in Parkinson’s here.

The study, which will be taking place at a single center in London is part- funded by Parkinson’s UK and is due to begin in February 2019. It will recruit 60 people with Parkinson’s taking either oral probiotic or placebo for 3 months.

Your questions answered

Will I be able to take part in this study?

If you are interested, please contact Dr Valentina Leta (email address kch-tr.PDresearch@nhs.net), who will run the study at the Parkinson centre of Excellence King’s College Hospital NHS Foundation Trust led by Prof K. R. Chaudhuri.

Should the study be a success, it will hopefully lead to further research and larger scale clinical trials of the benefits of improving the gut microbiotia in Parkinson’s.

Should I start using probiotics to improve my Parkinson’s?

This study is a world-first, which means we really don’t know if probiotics can improve the symptoms of Parkinson’s. And while Symprove has shown benefit for other conditions, there is no guarantee it will work for people with Parkinson’s.

Can I take part in other research?

Yes, there are many research studies looking for people both with and without Parkinson’s to take part. You can find out about them on our Take Part Hub.