Gut-brain axis takes center stage at Microbiome & Probiotic R&D and Business Collaboration Forum Europe

24 May 2023 --- The latest findings in gut health were unveiled yesterday and today at the Microbiome & Probiotic R&D and Business Collaboration Forum Europe in Rotterdam, the Netherlands. The forum, attended by NutritionInsight, explored several different studies focused on gut health and its connection to anxiety, depression, bipolar disorder and other brain-related health conditions.

One study is Netherlands-based research that investigated 150 people diagnosed with bipolar disorder or schizophrenia to find a correlation between psychiatric symptoms and gastronomical issues.

“At least in theory, food can do a lot of good, not only for the inflammatory response, but also for the brain,” Iris Sommer, psychiatrist and professor in neurosciences at the University Medical Center Groningen, the Netherlands, said in her presentation during the forum, “An apple a day keeps the psychiatrist away.”

“So, this is a questionnaire of several commonly observed customer intestinal complaints, and we are correlating them to the items of the brief psychiatric rating scale. We found that it’s especially the affective symptoms, quite specifically, those that are correlated to intestinal complaints.” 

“That’s interesting because these are not the most debilitating symptoms. So usually, if you look at, for example, schizophrenia, then one debilitating symptom is apathy. People that are not motivated, they will not go shopping, they will not cook, they will not take good care of themselves and their nutritional habits are typically very poor.”

She detailed that the research team were expecting the worst gastrointestinal symptoms among the people with less debilitating affective symptoms, and they were the ones that experienced abdominal issues.Iris Sommer, psychiatrist and professor in neurosciences at the University Medical Center Groningen, the Netherlands.

Nutrition for the brain
Furthermore, the researchers also study how fiber intake affects the brain. They expect a prevalence of Rotella DeCarli to see improved function in the gut, a lower immune activation and increased butyrate production, GABA metabolism and tryptophan metabolism – all important for the brain. 

“All these processes would be fabulous for people with severe psychiatric disorders,” Sommer highlighted. “You can use probiotics, but why not use some decent foods, as food has several other important advantages and can directly modulate immune cells in the gut.”

“About 80% of T cells are prevalent in the gut, so that they can be affected directly with food. And this is not some soft activation – these are actually from a pharmacological modulation.”

She exemplified polyphenols from fruits and vegetables as they increase anti-inflammatory T helper cells, arguing that healthy foods can directly induce an anti-inflammatory response in the gut. 

Additionally, foods high in saturated fatty acids from meat, dairy and sugar signal danger to the brain, which was shown in a study with mice to have a pro-inflammatory impact and induce sickness behavior in the brain.

Nutrition and neurotransmitters
Meanwhile, Simone Pyle, science and technology manager, gut microbiome at Unilever, detailed that GABA stands for GABA amino butyric acid, “so it’s a major inhibitory neurotransmitter within the brain. But it’s been found [in invitro studies] that you can produce this in the gut. Bifidobacteria lactobacillus bacteroides can also produce GABA in the gut.”Foods high in saturated fatty acids from meat, dairy and sugar signal danger to the brain, explained Sommer.

“An animal study showed how GABA receptor A and GABA receptor B can play into this. GABA receptor B is reduced within the brain’s frontal cortex when you have anxiety symptoms and all kinds of mood and behavior,” she continued.

She further detailed the study findings: “If you add probiotics, it can increase the amount of GABA receptors within the frontal cortex of the brain and other parts of the brain.” 

“So the amygdala and the hippocampus both live in GABA receptor B. But this has shown that it can kind of have that antidepressant started, as behavior is carried out and especially in GABA receptor A, which is often a target for some drug interventions that the lactobacillus strain naturally found the similar and present behavior as well.”

Mental health
Robert Brummer, a gastroenterology and clinical nutrition professor and director of the nutrition-gut-brain interactions research center in Örebro, Sweden, talked about probiotics and their potential to improve mental health.

Brummer detailed that in patients with diarrhea-predominant irritable bowel syndrome (IBS), over 80% suffer depression or anxiety disorder and IBS, which is also under-diagnosed because “gastroenterologists are not interested in that; they are more interested in providing biologicals.”

He further exemplified Parkinson’s disease as an example of a disease that originates in the gut. “Apparent barrier function in some way is involved in this building of aberrant Alpha-synuclein proteins, which are traveling from the gut to the brain and causing Parkinson’s disease.”

Brummer went on to share his perspective on probiotics for mental health, saying that nutritional and lifestyle interventions are changes that can be made throughout the whole life span. Even though direct changes are minor compared to medication or surgery, “the effect at the end is much larger,” he said.Robert Brummer, a gastroenterology and clinical nutrition professor and director of the nutrition-gut-brain interactions research center in Örebro, Sweden.

Prior and future research
A recent study from researchers at Harvard Medical School found a link between suppressing emotions and gut health among women. Additionally, China-based research found a link between Western diets and Crohn’s disease – a chronic inflammatory bowel disease in the gastrointestinal tract.

Pyle at Unilever noted that, based on a survey, 77% of people in the US have regular stress-related symptoms and the UK has a similar percentage.

“So 74% of people found themselves unable to cope due to stress. We see it is a big consumer area, and we think the gut microbiome could be the key to unlocking some of these problems,” she underscored.

“But, talking about probiotics, don’t forget the importance of the diet because the diet works in a much broader way than only probiotics. So I would not only advocate using probiotics, but of course, you must have a healthy diet,” Brummer at the Örebro research center concluded.

By Beatrice Wihlander, reporting from the 11th Microbiome & Probiotic R&D and Business Collaboration Forum Europe