Is the Gut Microbiota a New Factor Contributing to Obesity and Its Metabolic Disorders?

Figure 4

New and old models describing the factors that contribute to the development of metabolic diseases. An old model is based on direct interactions between the environmental factors and genetic variations of individuals (nutrigenomic interactions). A new model includes the emerging discoveries related to the gut microbiota and the host. Environmental factors such as dietary fats affect the composition of the gut microbiota. Conversely, different profiles of gut microbiota regulate the production of short-chain fatty acids. Thus, the two way interactions can be described as nutri-metagenomic interactions. Crosstalks between the host and gut microbiota can also happen (host-metagenome interactions). Evidence that mutations of a host gene lead to alterations of gut microbiota profile and that mice colonized with different gut microbiota have different metabolic phenotype s supports the host-metagenome interactions.