A new mathematical model for the interaction of bacteria in the gut could help design new probiotics and specially tailored diets to prevent disease. The research, from Chalmers University of Technology in Sweden, was recently published in the journal PNAS.
“Gut bacteria have an important role to play in health and disease development, and our new mathematical model could be extremely useful in these areas,” says Jens Nielsen, professor of systems biology at Chalmers, who led the research .
The new paper describes how the mathematical model performed when making predictions for two previous clinical studies, one involving Swedish infants and the other with obese adults in Finland.
The studies involved regular measurements of health indicators, which the researchers compared to predictions made from their mathematical model – the model was found to be very accurate in predicting several variables, including how the liquid diet shifted. to solid food in Swedish infants affected their intestinal bacterial composition.
They also measured how the gut bacteria of obese adults changed after switching to a more restricted diet. Again, the model’s predictions have proven to be reliable.
“These are very encouraging results, which could allow the computerized design of a very complex system. So our model could be used to create personalized healthy diets, with the ability to predict how the addition of specific bacteria as new probiotics could have an impact on a patient’s health, ”says Jens Nielsen.
Many factors at play
There are a lot of different things that affect the way different bacteria grow and work in the intestinal system. For example, what other bacteria are already present and how they interact with each other, as well as how they interact with the host – i.e. us. Bacteria are also affected by their environmental factors, such as the diet we eat.
All of these variables predict the effect of adding bacteria or changing the diet. One must first understand how these bacteria are likely to act when they enter the gut or how a change in diet will affect the composition of the gut. Will they be able to grow there or not? How will they interact and possibly affect the bacteria already present in the gut? How do different diets affect the gut microbiome?
“The model we have developed is unique because it takes all these variables into account. It combines data on individual bacteria as well as how they interact. It also includes data on how food moves through the gastrointestinal tract and affects bacteria along the way. These can be measured by looking at blood samples and looking at metabolites, the end products that form when bacteria break down different types of food, ”explains Jens Nielsen.
The data to build the model was gathered from many years of pre-existing clinical studies. As more data becomes available in the future, the model may be updated with new features, such as descriptions of hormonal responses to food intake.
A huge potential asset for future healthcare
Research on diet and the human microbiome, or gut bacterial composition, is an area of research of great interest, both among researchers and the general public. Jens Nielsen explains why:
“Changes in bacterial makeup can be associated with or signify a large number of ailments, such as obesity, diabetes or cardiovascular disease. They can also affect how the body responds to certain types of cancer treatments or on specially developed diets. “
Working with the bacterial composition therefore offers the potential to influence disease progression and overall health. This can be done through treatment with probiotics – carefully selected bacteria that are believed to help improve health.
In future work, Jens Nielsen and his research group will use the model directly in clinical studies. They are already participating in a study with Sahlgrenska University Hospital in Sweden, where older women are being treated for osteoporosis with the bacteria. Lactobacillus reuteri. It has been seen that some patients respond better to treatment than others, and the new model could be used as part of the analysis to understand why this is so.
Treating cancer with antibodies is another area where the model could be used to analyze the microbiome, helping to understand its role in why some patients respond well to immunotherapy, and others not.
“It would be an incredible asset if our model could begin to identify bacteria that could improve the treatment of cancer patients. We think it could really make a big difference here, ”says Jens Nielsen.