Exchange Paves the Way for New Probiotic Applications
New and exciting data were shared, contributing to establishing the interactions between this “brain-gut” axis and the gut microflora, and the potential of probiotic use.
25/11/08 Over 40 scientists and experts from different universities and research centres across North America and Europe gathered this month in Quebec City to participate in Institut Rosell-Lallemand’s Scientific Exchange. With varying though complementary backgrounds ranging from neuroscience to gastroenterology through animal behaviour, all shared a common interest in probiotics research and applications. The meeting focused on the intricate and complex relationship between the brain and the gut. New and exciting data were shared, contributing to establishing the interactions between this “brain-gut” axis and the gut microflora, and the potential of probiotic use. Fascinating behavioural studies in animal models showed that probiotics can help to manage stress and anxiety and influence behaviour, which helps to explain observations in human clinical trials. Moreover, complex diseases known to involve the brain-gut axis, such as Irritable Bowel Syndrome (IBS), can be targeted with probiotics. This unique interdisciplinary meeting was a real platform for exchanging ideas and methodological approaches. It allowed the participants to set new directions for future probiotics research and paved the way for new applications.
The idea of a brain–gut axis is not a new concept, the first scientific studies of the subject dating back to the 1960s. The fact that communication works both ways and that the gut can talk to the brain is a more innovative approach. Even more novel is the idea of looking at the role of the intestinal microflora, or microbiota, with the addition of probiotics, in this brain-gut cross-talk.
As explained by Professor Stephen Collins of McMaster University Medical Centre (Canada): “The intestinal microbiota has profound effects on host function and should be incorporated into a modern conceptualization of the gut-brain axis.” He added: “In this model, changes in brain responses, such as stress or anxiety, influence the physiology of the gut, altering the habitat for the microbiota. The microbiota, in turn, influences gut physiology and immunity at the gut mucosa level. Our recent data indicate that perturbation of the microbiota also influences behaviour. These findings raise the possibility that the microbiota plays a pivotal role in functional gastro-intestinal disorders such as Irritable Bowel Syndrome, where the perturbation of the microbiota not only induces gut dysfunction, but may also contribute to the psychiatric co-morbidity that exists in up to 60% of these patients.”
Until now, probiotics had mostly been documented for their role in digestive health and functions (prevention of diarrhoea or bloating, transit regulation, lactose intolerance…). Recently, scientists have also studied their interactions with the immune system, either to stimulate the body’s defences or prevent allergies. With their action on the gut microflora balance, probiotics could also affect the brain-gut axis, as confirmed during the seminar.
More than ten different scientific studies were presented, showing how specific probiotic preparations play a role in animal behaviour, their reaction to stress, anxiety, or memory formation post-infection. For example, Didier Desor, Professor of Behavioural and Cognitive Neurosciences at University Henri Poincaré in Nancy (France), presented a pre-clinical study with a probiotic preparation (Probio’Stick from Institut Rosell-Lallemand) which has already been shown to be effective in humans in reducing the gastro-intestinal symptoms linked to stress. Using a mouse model validated with Diazepam, it was shown that the probiotic was able to reduce signs of anxiety, displaying an “anxiolytic-like” effect. Such effect had not been previously described with probiotics.
For animals raised with modern production methods, stress is a recurrent issue, making them a good model for researching the effects of probiotics on well-being and stress. Several significant studies were presented showing how probiotics, which are increasingly used in animal nutrition, can impact stress and behaviour. For instance, a ruminant-specific probiotic yeast can help regularize feeding patterns in dairy cows. Other probiotics help reduce stress in sows around parturition, an extremely critical step of the pig production cycle.
All these fascinating results open the way to a new area of probiotic applications in human health. Probiotics could improve quality of life for chronic stress or anxiety sufferers, for example.
One of the evident conclusions that came from the numerous discussions during the seminar was the renewed certitude that all strains are different. The benefits exerted by a particular microbial strain or blend of strains cannot be extended to others. Some of the studies presented were conducted on different probiotic preparations and the outcomes were diverging. We are just beginning to comprehend the necessity of matching a probiotic with a state of health.
During the round-table discussion, it came out loud and clear that experts from different disciplines in both human and animal health have a lot to learn from each other. Professor Phil Sherman, from the Hospital for Sick Children, University of Toronto (Canada), who chaired the discussion, concluded that: “the seminar was a great opportunity to build bridges, not only between the industry and academia but also between the different disciplines.” We are learning that nutrition, gut health and psychological health need, more and more, to be linked together. All the participants left with new ideas and concepts which will be exchanged through new collaborations and interactions.
