A billion reasons to attend Biotech Day


A possible connection between Parkinson’s disease and bacteria in the digestive system is just one of the fascinating stories from VIB’s Biotech Day

Invisible but unmissable

The billions of bacteria and other microbes that live around us, and inside us, are the stars of this year’s Biotech Day. The aim of the free event next Sunday is to showcase research underway at VIB, the Flemish life sciences research institute, and to give the public a peek inside its laboratories in Leuven.

Some of the themes in the programme, in Dutch and English, will already be familiar. These range from the use of microbes in food production and environmental clean-up, to the challenge of antibiotic resistance.

But there are also more surprising ideas that will make anyone interested in science sit up and take notice. For example, could there be a connection between the bacteria that live in our intestines and a nervous disorder such as Parkinson’s disease?

At first sight this seems unlikely, but it is proving a fascinating area of enquiry for Roosmarijn Vandenbroucke, who leads a research group at the VIB-UGent Centre for Inflammation Research. Her broad area of interest is sepsis, which occurs when the immune system over-reacts to an infection, triggering inflammation throughout the body.

Septic shock can have an effect on the brain, even a long time after sepsis is experienced

- Roosmarijn Vandenbroucke

This can have a significant impact on the brain. “If people survive systemic inflammation, or septic shock,” says Vandenbroucke, “they often suffer from some cognitive or other brain effects, sometimes even a long time after they experienced the sepsis.”

Exploring this further means thinking about how the effects of inflammation might reach the brain. When it comes to the blood, there is a filter known as the blood-brain barrier that should protect the brain from most effects of inflammation.

But then there are other possible routes, such as the vagus nerve, which connects the brain with the heart, lungs and digestive system. “There you don’t have a barrier at all.”

This is where Parkinson’s comes in. Back in the 1980s, patients with certain kinds of stomach complaint were treated by having part of their vagus nerve cut. Following up decades later, it appears that they have a much reduced chance of developing Parkinson’s disease.

There are also other reasons for thinking that Parkinson’s disease might be connected to the digestive system. For example, constipation as a common early symptom, appearing long before hand tremors or problems with balance and movement. So perhaps the disease starts there.

The current thinking is that Parkinson’s disease is caused by an accumulation in the brain of a protein called alpha-synuclein. Inflammation appears to encourage the protein to collect together in this way, and more recently it has been found that certain components derived from bacteria have a similar effect.

“Together with other research, this makes us think that alpha-synuclein may start out in the gut and is then able to travel via the vagus nerve into the brain,” explains Vandenbroucke.

This is not a hypothesis that can be tested in people. “So in our lab we use mice to do that. We add the alpha-synuclein to the gut or the gut wall, and then see whether or not it is able to travel via the vagus nerve to the brain. We are also looking at whether changes in the microbiome – the bacteria living in the gut – or changes in systemic inflammation might have an effect on the movement of alpha-synuclein from the gut to the brain.”

A clinical trial will assess whether having healthy gut bacteria affects the progression of Parkinson’s disease

One thing that can be tested in humans is whether having healthy gut bacteria in a more general sense affects the progression of Parkinson’s disease. A clinical trial is currently being set up at Ghent University Hospital to do just that, with volunteers in the middle stages of Parkinson’s disease.

Half will be given a “transplant” of gut microbes from someone with a particularly diverse and healthy microbiome, while half will simply receive a sample of their own gut microbes. The progress of the disease will then be followed for a year to see if there is any difference between the two groups.

None of this would be possible without the support of patient groups, and her colleagues: Arnout Bruggeman (UGent, UZ Gent Neurology) and Jeroen Raes (KU Leuven), both of whom are also speaking during Biotech Day; Debby Laukens and Danny De Looze (both UGent, UZ Gent Gastroenterology); and Patrick Santens (UGent, UZ Gent Neurology).

“Doing a clinical trial is not easy, particularly when you are combining two different fields, in this case gastroenterology and neurology. So the collaboration is essential to make this clinical trial possible.”

Biotech Day, 20 October 12.30-17.30, Campus Arenberg, Kasteelpark Arenberg 10, Heverlee (Leuven)

Photo top: Biotech Day offers talks and demonstration to young and old ©Ine Dehandschutter/VIB
Photo above: professor Roosmarijn Vandenbroucke (right) receives the 2017 Baillet Latour grant for medical research from Queen Mathilde of Belgium ©Thierry Roge/BELGA