Does gut microbiota play a role in the development of type 1 diabetes?

Investigators in the DIABIMMUNE project are deciphering the mechanisms behind the development of type 1 diabetes. Collaboration between Finnish, Estonian and American researchers has generated observations depicting significant diabetes-associated changes in the maturation of the gut microbiota in young children developing type 1 diabetes.

The dynamics of the developing gut microbiota was observed based on monthly stool samples from birth until the age of 3 years in the DIABIMMUNE birth cohort. During the follow-up, the metabolism of the gut microbiome remained stable in healthy children even though the species of the microbiome delivering these metabolites were highly variable. In healthy children, the most abundant microbial species observed at birth remained abundant throughout the follow-up, although the diversity of the microbiome increased by age.

Children, who developed disease-associated autoantibodies and were later diagnosed with clinical diabetes, differed from healthy children regarding the composition and metabolism of their gut microbiota. The appearance of autoantibodies was accompanied by a decrease in the microbial diversity, and in this impoverished microbiome, microbial species and metabolites associated with inflammatory processes were increased. Diabetes-associated autoantibodies represent the first detectable sign of the initiation of the disease process resulting in clinical type 1 diabetes.

These observations imply that the gut microbiota hardly play any role in the initiation of the disease process resulting in diabetes but it may have an important role in the progression of the disease process from autoantibody positivity to clinical symptoms. These findings generate a need for further investigations aimed at finding out whether the prediabetic disease process could be delayed or even prevented by modulating the gut microbiota in individuals at increased risk for type 1 diabetes.

These results will be published in the February issue of the journal Cell Host & Microbe.

In addition to the University of Helsinki, there are several partners involved in the DIABIMMUNE study: the Universities of Tampere and Turku, the Finnish National Institute of Health and Welfare, as well as researchers from Estonia, Russian Karelia, Germany, the Netherlands, Denmark, and USA.

Article: A. D. Kostic, D. Gevers, H. Siljander, T. Vatanen, T. Hyötyläinen, A.-M. Hämäläinen, A. Peet, V. Tillmann, P. Pöho, I. Mattila, H. Lähdesmäki, E. A. Franzosa, O. Vaarala, M. de Goffau, H. Harmsen, J. Ilonen, S. M. Virtanen, C. B. Clish, M. Orešič, C. Huttenhower, M. Knip, R. J. Xavier. The Dynamics of the Human Infant Gut Microbiome in Development and in Progression towards Type 1 Diabetes. Cell Host Microbe 2015. doi: 10.1016/j.chom.2015.01.001

Further information can be requested from:
Professor Mikael Knip
Principal Investigator of the DIABIMMUNE Study
E-mail: mikael.knip@helsinki.fi
Tel.: +358 50 448 7722

Dr. Heli Siljander
Senior Researcher
E-mail: heli.siljander@helsinki.fi
Tel.: +358 50 319 9364