"There is a high diversity among the bacteria of the microbiota. While humans have a genome with approximately 23,000 different genes, the human microbiota has more than two million different genes", said de Vadder. This diversity is subject of numerous scientific investigations. For example, a different composition of bacteria could be found in obese people than in non-obese people. This observation brought scientists to the idea that microbiota could play a role in regulating the energy homeostasis.
In obesity research, dietary fiber from fruit and vegetables have been shown to be beneficial for metabolism and weight regulation. They serve as food for the bacteria in the intestine, especially in the colon. During the digestion of these oligosaccharides by the bacteria, new compounds are generated in the metabolism such as the short-chain fatty acids acetate, butyrate and propionate. “Currently it is assumed that these short-chain fatty acids activate gluconeogenesis in the cells of the intestinal wall, which leads to a glucose release into the portal vein. This sends a signal to the brain that can regulate hunger and saturation and thus influence the energy metabolism." De Vadder recently demonstrated in the mouse model that the precursor of propionate, succinate, possesses this quality. The extent to which these results from basic research can be transferred to humans must now be further investigated in clinical intervention studies. However, research is just beginning to understand the mechanisms and complex relationships between the microbiota and the brain (central nervous system)
Text: TA6, Dr. Maike Gutmann, DGE