Obesity, diabetes and other metabolic complications are all pathologies that have become public health issues today, although we do not know how to explain their prevalence. A team of researchers from INRA, Danone, AP-HP, Inserm and Sorbonne University has just highlighted in a preclinical study in vivo, that the metabolic disorders associated with a diet high in fat are aggravated by the proliferation of a pro-inflammatory bowel bacteria, Bilophila wadsworthia which helps to damage the intestinal barrier. These effects are mitigated by a probiotic bacterium, Lactobacillus rhamnosus CNCM I-3690. These results pave the way for the development of nutritional approaches and probiotics that target the microbiota. They are published on July 18, 2018 in the journal Nature Communications.
Bilophila wadsworthiahis little name probably does not tell you anything. It is true that, in a healthy individual, it represents less than 0.1% of gut microbiota bacteria. In contrast, in individuals whose diet is high in fat, it is significantly more abundant. However, changes in the composition of the microbiota are commonly associated with metabolic dysfunctions without the mechanisms underlying this relationship being well understood.
In a preclinical study in vivo, researchers from INRA, Danone, AP-HP, Inserm, Sorbonne University and their colleagues have shown that a diet high in fat creates conditions conducive to the proliferation of intestinal bacteria, such B. wadsworthia. This multiplication is accompanied by a worsening of the various parameters that characterize the metabolic syndrome (eg, impaired glycemic tolerance, decreased insulin sensitivity, or increased blood and liver lipids). It is also associated with intestinal inflammation and dysfunction of the intestinal barrier and disorders of bile salt metabolism, favorable to the development of this bacterium.
The scientists then explored the therapeutic potential of a probiotic bacterium, Lactobacillus rhamnosus, revealing the interest of a specific strain, CNCM I-3690. This limits the proliferation of B. wadsworthia, protects the intestinal barrier from its pro-inflammatory effects and improves glucose regulation parameters.
This work highlights the role of an intestinal bacteria, B. wadsworthia, in worsening metabolic effects of a high-fat diet. These results, if confirmed in humans, pave the way for the preventive and therapeutic use of probiotic strains that can reduce the spectrum of inflammatory and metabolic diseases, such as diabetes and obesity, by restoring functions provided by a balanced intestinal microbiota and by helping to improve the quality of diets.