Bugs found in the guts of humans, which play an important part in peoples metabolic makeup, have been transplanted into mice to further understanding of the human and animal metabolic system, reveals a new study in the journal Molecular Systems Biology.
Bugs in the gut are known as gut microbes and they live symbiotically in human and animal bodies. The new study involved understanding the major role that gut microbes have in determining how the body absorbs fat and digests fibre, and their effects on metabolic pathways in the body. The researchers, from Imperial College London and Nestl Research Center, Lausanne, Switzerland, found that microbes affect the way fats are absorbed and metabolised, by affecting bile acids. Bile acids are made by the liver to allow emulsification of fats in the upper gut. The researchers found that gut microbes can change how effective this emulsification process is because they metabolise bile acids.
The bile acids are also hormonal regulators which change the way fat is processed in the liver, so changes made by gut microbes to bile acid metabolism can affect this internal process.
The scientists also explored how microbes break down fibre in the lower gut. Certain microbes allow dietary fibre to be digested and the more effective these microbes are, the more calories are absorbed from the diet.
Different people have different types of gut microbes living inside them and abnormalities in some types have recently been linked to diseases such as diabetes and obesity. The scientists believe that transplanting the bugs found in humans into mice will enable better understanding of gut microbes effects, good and bad, and help them to develop better treatments (including probiotics and functional foods) for a wide range of conditions.
Professor Jeremy Nicholson, one of the lead authors of the paper from the Department of Biomolecular Medicine at Imperial College London, said: "Humans
Contact: Laura Gallagher
Imperial College London