Over the last 10–15 years, our understanding of the composition and functions of the human gut microbiota has increased exponentially. To a large extent, this has been due to new ‘omic’ technologies that have facilitated large-scale analysis of the genetic and metabolic profile of this microbial community, revealing it to be comparable in influence to a new organ in the body and offering the possibility of a new route for therapeutic intervention. The good news: the potential of modulating the gut microbiota offers new options in therapy.
A delicate balance
There is growing evidence that dysbiosis or microbial disbalance of the gut microbiota is associated with the pathogenesis of both intestinal and extra-intestinal disorders. Intestinal disorders include inflammatory bowel disease, irritable bowel syndrome (IBS), and coeliac disease, while extra-intestinal disorders include allergy, asthma, metabolic syndrome, cardiovascular disease, and obesity. Today, data, coming from animal and human models, suggest that obesity and T2D are associated with a profound dysbiosis. Specifically, patients with T2D have reported alterations in the composition and function of their gut microbiota. This suggests a microbe-mediated mechanism of disease.
The gut signature of Diabetes
Importantly, recent research unveiled that especially butyrate-producing bacteria (which are thus able to exert profound immunometabolic effects), such as Roseburia intestinalis and Faecalibacterium prausnitzii concentrations were lower in T2D subjects. Endotoxaemia, most likely gut-derived, has also been observed in patients with T2D and might play a key role in metabolic inflammation. Also, certain antidiabetic drugs, such as metformin can interfere with the intestinal microbiota. Finally, specific members of the microbiota, such as Akkermansia muciniphila, might be decreased in diabetes and, when administered to murines, exerted antidiabetic effects.
Therefore, as a ‘gut signature’ becomes more evident in T2D, a better understanding of the role of the microbiota in diabetes might pave the way for new therapeutic principles.
Our environment alters gut microbiota
Diet is one of the most important factors that has an influence on the gut microbiota. Animal studies have demonstrated that changes in diet may result in changes in the gut microbes, and human studies have confirmed these findings. A few studies have shown that human gut microbiota can adapt and shift within a few days of exposure to a yogurt diet. One study among healthy volonteers, which included yogurt in their diet, demonstrated the presence of food-borne bacteria in their faeces. This indicates that the consumption of yogurt may ensure some advantageous changes to the equilibrium and metabolic activities of the indigenous microbiota. However, recent data showed that long-term diet is particularly strongly associated with gut microbiota composition.
Key-learnings
- Gut microbiota is a complex community of bacteria in the intestine
- Genetic, diet and environmental factors can alter gut microbiota
- An altered gut signature promotes intestinal inflammation and subsequently low grade systemic inflammation in T2D
- The gut microbiota, influenced by DIET, may be linked to human T2D
- Few studies are related to yogurt and gut microbiota, but results confirm the impact of yogurt on keeping a healthy gut microbiota.
