New research on obesity and diabetes led by Professor Patrice D. Cani, research associate of the FRS-FNRS at the Louvain Drug Research Institute (UCL) and investigator for WELBIO (UCL), has recently been published in the prestigious scientific journal PNAS (Proceedings of the National Academy of Sciences of the United States of America). 

Researchers from the UCL have just discovered that the presence of a particular intestinal bacterium plays an essential role in preserving the barrier function of the gut and protects against the development of obesity, and the storage of fats in type 2 diabetes and inflammation induced by a diet rich in fats. The intestinal bacterium, named Akkermansia muciniphila, was first discovered in 2004 by Prof. Willem de Vos and his team from the University of Wageningen (The Netherlands).

Professor Cani and his team discovered that the presence of Akkemansia muciniphila in the intestine of obese and type 2 diabetic mice was 100 times lower than that of healthy mice, revealing that this bacterium is more abundant among the healthy mice compared to that of the obese and type 2 diabetic counterparts. Coincidentally, Amandine Everard, PhD student of Patrice D. Cani’s team and first author of the publication, discovered that the thickness of the mucus layer covering the colon was also much finer in obese mice and subjects with type 2 diabetes. It is worth noting that the human gut shelters roughly 100 trillion bacteria, among which several have not yet been identified but, of those identified and contrary to the majority of the intestinal bacteria, Akkermansia muciniphila lives in the mucus layer which coats and protects the intestinal cells. As a matter of fact, it represents between 3 and 5% of the bacteria that colonize in the human colon however, its actual role up to this point still remained a mystery.

Furthermore, researchers were led to the conclusion that there was also an inverse relationship between the number of Akkermansia muciniphila in the intestine and the body weight of the subject. In other words, the more overweight the subject the lower the number of Akkermansia muciniphila present in the intestinal microbiota. Nevertheless, despite this research and discovery, the mechanisms explaining this potentially “fat-fighting” effect still remained unknown, until now!

Because Akkermansia muciniphila lives in the mucus covering and protecting the intestinal cells, its relative closeness with the cells of the intestinal lining led these researchers to believe that it could have an actual dialogue with the host (or body) which is exactly what has been demonstrated by Professor Patrice D. Cani and his team.

Thanks to the wonderful collaboration established between Prof. Cani, Prof. de Vos, and their respective researchers, results have demonstrated that the administration of live Akkermansia muciniphila into obese and diabetic mice allows the weakened or thinned mucus barrier in the intestine to be restored. As a result, there is a decrease in the storage of fats and a better oxidization of fats of the adipose tissues thereby protecting the animals from diabetes and inflammation.

Aside from highlighting new mechanisms, this discovery may provide further explanation as to how Akkermansia muciniphila and the cells of our intestine manage to establish a dialogue. Among the molecules involved in this possible dialogue, the researchers identified endocannabinoïd* type substances as well as an antimicrobial molecule (Reg3g) produced by our own intestinal cells.

Suggesting that this new bacterium Akkermansia muciniphila could play an important role in the function of our intestine and in the regulation of the storage of fats, this bacterium could quite possibly be the key to unlocking the door that leads to the prevention and treatment of obesity and type 2 diabetes.

* The endocannabinoid system is a group of bioactive lipids and their receptors that are involved in a variety of physiological processes including appetite, pain-sensation, gastro-intestinal functions, immune regulation, mood, and memory.

Sources:
http://www.uclouvain.be/442972.html
http://www.uclouvain.be/cps/ucl/doc/ac-arec/documents/13-05-2013_recherche_UCL_bacterie_intestinale.pdf
PNAS publication

Contacts:
Prof. Patrice Cani –

Isabelle Decoster