With Type 1 diabetes the beta cells in the pancreas stop making insulin. The illness and develops quickly because the level of insulin in the bloodstream becomes very low. Type 1 diabetes is treated with insulin injections and diet.
Although connections between the bacteria that reside in the human gut (the microbiome) and health have been shown before, including correlations between the microbial flora and diabetes, the new study is the most comprehensive to date. The study followed infants who were genetically predisposed to diabetes over a long time period.
The study concluded that the onset of type I diabetes was preceded by a drop in microbial diversity (the range of different microbial species that are commonly found inside the gut.)
In total 33 infants were tracked. The children were drawn from Finland and Estonia. With the children, as they developed diabetes their gut bacterial diversity fell by one quarter. The bacteria that were lost tended to be those species classed as either harmless or beneficial. Consequently, the loss of these competing microbes led to an increase in organisms considered to be harmful. With the growing dominance of these species, there was a tendency towards inflammation of the gut. Previously, diabetes has been linked with inflammation.
The pattern with the children affirmed some data previously gathered from animal studies. Here, when microbiota from mice that were predisposed to autoimmune diabetes (like diabetes) was transferred to mice that did not have the condition, the mice went onto develop autoimmune diabetes.
Further research is needed and there are other factors, such as environment, that need to be accounted for. Nonetheless, the results are of sufficient interest to warrant further study.
The study was conducted by researchers based at the Broad Institute of MIT and Harvard, Massachusetts General Hospital. The research has been written up in the journal Cell Host & Microbe, with the paper titled “The Dynamics of the Human Infant Gut Microbiome in Development and in Progression toward Type 1 Diabetes.”
