An international research team has uncovered compelling evidence that gut-microbe-derived molecules may play an important role in shaping the developing immune system during early childhood. The findings provide a new perspective into how early gut microbiome development may contribute to the risk of autoimmune diseases, including type 1 diabetes. 

The study analysed more than 300 stool samples collected from children between 3 and 36 months of age. These children carried a genetic risk for type 1 diabetes, and some went on to develop islet autoantibodies, early markers of the disease. Researchers tracked over 100 microbially conjugated bile acids, a class of compounds that were only recently discovered and remain poorly understood.

Bile acids are made from cholesterol in liver and secreted after every meal in the intestine to help digest fat. Scientists have only recently learned that bacteria in our intestine can recombine them with different amino acids as well as other molecules, producing a vast range of new bile acid structures. These microbially produced molecules were long overlooked and were discovered only within the past few years.

“This is the first study to show how these gut-microbe-derived bile acids develop during the first years of life,” notes Professor and principal investigator Matej Orešič from Örebro University in Sweden and the University of Turku in Finland.

The research indicates that as children grew, liver-derived primary bile acid conjugates declined, while gut-microbe-derived secondary bile acid conjugates steadily increased.

The researchers also identified specific gut bacteria whose abundance was strongly linked with these bile acid patterns.

“This fits with currently emerging evidence that bile acids are key to gut microbiome and immune maturation during early life,” points Academy Research Fellow Santosh Lamichhane from the University of Turku.

Original research article: Microbiome-derived bile acid signatures in early life and their association with islet autoimmunity

Read full press release here: in English I in Finnish

For more information please contact:

Matej Oresic

Group Leader, Professor

Oresic Lab | Systems Medicine | Metabolomics Core

matej.oresic@utu.fi

Santosh Lamichhane

Academy Research Fellow, Docent

Oresic Lab | Systems Medicine

santosh.lamichhane@utu.fi