Section showing the interaction of the intestinal microbiota and epithelium at the level of the colon. In blue, the mucus secreted by the intestinal epithelium to protect itself from the microbiota. In pink, the nuclei of the epithelial cells. © Noemie Daniel/Inserm
Emulsifiers are food additives used to improve the texture and extend the shelf life of foods. We found in many processed foods (ice cream, packaged cakes, sauces, etc.), even if their harmful effects on intestinal balance have been demonstrated. In a new study, scientists from Inserm, CNRS and the Université Paris Cité of the Institut Cochin in Paris aspired to counteract the deleterious effects induced by the consumption of emulsifiers by fortifying the intestinal epithelium through its repopulation by a bacterium naturally present in the intestine: Akkermania muciniphila. The addition of this bacterium to the intestinal microbiota would avoid the damage caused by the consumption of emulsifying agents. These are the data, published in the magazine intestineconfirm the growing potential from Akkermansia muciniphila as a probiotic.
Millions of people consume emulsifying agents daily. These products are on the list of the most used food additives in the food industry. And for good reason, they improve the texture of foods and extend their shelf life. For example, emulsifiers such as lecithin and polysorbates guarantee the creamy consistency of industrial ice cream and prevent it from melting too quickly once served.
Previous work carried out by the team of Benoît Chassaing, Inserm researcher at the Cochin Institute (Inserm/CNRS/Université Paris Cité), has shown that the consumption of some emulsifying agents leads to an alteration of the intestinal microbiota. and its interaction with the digestive tract. These alterations in the microbiota lead to chronic intestinal inflammation and metabolic dysregulation. Specifically, this research has shown that the consumption of food emulsifiers induces the ability of some elements of the microbiota to come into close contact with the epithelium, the first line of defense of the normally sterile digestive tract.
In this new study, the researchers wanted to counteract the deleterious effects induced by the consumption of emulsifiers by fortifying the intestinal epithelium. For this, they were more specifically interested in the bacterium Akkermansia muciniphilawhich, naturally present in the intestine, has already been shown to have an impact on the interactions of the microbiota with the rest of the body.
We also know that the quantity of this bacterium is reduced following the consumption of emulsifiers.
Groups of mice then received emulsifying agents through their diets, whether or not supplemented with a daily dose ofAkkermansia muciniphila. The scientists observed that while consumption of dietary emulsifying agents was sufficient to induce chronic inflammation associated with metabolic derangements and hyperglycemia, mice receiving Akkermansia muciniphila they were fully protected against such effects. The administration ofAkkermansia muciniphila it was also sufficient to prevent all the molecular alterations normally induced by the consumption of emulsifying agents, and in particular the approach of bacteria from the wall of the epithelium.
“This work supports the idea that the use ofAkkermansia muciniphila as a probiotic it could be one approach to maintain metabolic and intestinal health against modern stresses such as emulsifying agents promoting chronic intestinal inflammation and its adverse consequences. Furthermore, this suggests that intestinal colonization by Akkermansia muciniphila could predict the individual propensity to develop intestinal and metabolic disorders following the consumption of emulsifiers: the greater the presence of the bacterium, the more the individual would be protected from the harmful effects of food additives on the microbiota”explains Benoît Chassaing, the last author of the study.
 All microorganisms – bacteria, viruses, parasites and non-pathogenic fungi, called commensals – that live in the intestine.