The human body contains ten times more bacteria than human cells. Most of these bacteria comprise the normal gut microbiota. Our bodies thus contain a vast number of bacterial genes in addition to the genes in our own cells, and are collectively known as the metagenome.
Three Swedish, Gothenburg-based research groups led by Jens Nielsen at Chalmers, and Fredrik Bäckhed and Björn Fagergberg at the Sahlgrenska Academy, compared the metagenome of 145 women with diabetes, impaired glucose tolerance and healthy controls. They showed that women with type 2 diabetes have an altered gut microbiota.
Furthermore, healthy women have higher numbers of gut bacteria known to be producers of butyrate, a fatty acid that has previously been linked to beneficial health effects.
On the basis of these findings, the researchers developed a new model that can distinguish between patients with type 2 diabetes and healthy women by analysis of the metagenome. This model has better predictive value than the classical predictive markers used today, such as body-mass index and waist-hip ratio.
“By examining the patient’s gut microbiota, we could predict which patients are at risk of developing diabetes. The big challenge is to find out whether the composition of the gut microbiota promotes the onset of age-related diabetes. If this is the case, this would indicate new opportunities to prevent the disease,” says Professor Fredrik Bäckhed.
“In this study, we have developed new methods to analyze the metagenomic data and have been able to exploit much more of the ‘unknown’ metagenome, that is, the bacteria that have not been previously mapped,” continues Jens Nielsen, Professor of Systems Biology at Chalmers University of Technology. “The study is an excellent example of how novel technologies, developed in connection with Chalmers’ initiative in life science, can assist in analyzing large amounts of data from the clinic.”
Last year, the researchers demonstrated that an altered gut microbiota in humans is associated with symptomatic atherosclerosis and stroke. Read about it here
Caption, top picture: Bacteria (orange) on gut mucus layer in a mouse. Photo: Mattias Bergentall.
Caption, lower picture: Jens Nielsen. Photo: Jan-Olof Yxell.
Jens Nielsen, Professor of Systems Biology at Chalmers University of Technology, +46 702-436 618,firstname.lastname@example.org
Fredrik Bäckhed, Professor of Molecular Medicine at the Sahlgrenska Academy, University of Gothenburg, +46 31 3427833, +46 70-2182355, fredrik.backhed @ wlab.gu.se
Swedish research on gut microbiota
Several internationally recognized research groups in the Gothenburg region of Sweden are studying the metagenome and how variations in the gut microbiota are linked to various diseases.
Jens Nielsen's research group at Chalmers University of Technology has developed several analytical platforms for metagenomic data and computer models to predict how the metagenome responds to different diets.
Read more here
Fredrik Bäckhed’s research group at the Sahlgrenska Academy maps how bacteria contribute to diabetes and cardiovascular disease by combining patient-oriented research with advanced animal models.
Read more here
Björn Fagerberg together with Göran Bergström at the Sahlgrenska Academy have led several population-based studies and are now a driving force in several major studies to examine interactions between the metagenome and diabetes and cardiovascular disease.