Three things that occur in early childhood were recently discovered: the development of the immune system, the maturation of the gut microbiome and the appearance of the first T1D-associated autoantibodies. Weird, huh?
The gastrointestinal microbiota has been described as a ‘hidden organ’ based on its ability to perform diverse physiological functions such as protecting against pathogens, producing energy, maintaining intestinal epithelial integrity and controlling immunological activities.
Research has shown many notable differences in the intestinal microbial profile between T1D patients and controls, indicating a close interaction between T1D development and gut microbiota.
Attention New Moms!
Here is some evidence supporting the causal role of the gut microbiota in the pathogenesis of T1D in human studies:
- Breast milk may decrease the risk of T1D onset because the microbial composition of breast-fed infants was characterized by a more stable gut microbiome compared to non-breast-fed infants.
- The use of probiotics during the first four weeks after birth reduced the risk of beta cell autoimmunity in infants genetically susceptible to T1D compared to those with no supplementation.
- A placebo-controlled pilot study in children with T1D showed that consumption of prebiotics could alter the gut microbiota composition and decrease intestinal permeability, leading to improved beta cell function.
A Little Dirt Won’t Hurt You
The maturation of the gut microbiome is also closely linked to the development of the immune system.
- The intestinal microbiome may influence the pathogenesis of T1D by affecting the immune system and/or gut permeability.
- It has been hypothesized that due to the interaction between bacterial composition and the innate immune system, infants with early exposure to specific microorganisms, may be much less likely to develop autoimmune diseases, like T1D, later in life.
- In one study, it was found that NOD mice living in a clean environment were more likely to develop diabetes and infection than NOD mice exposed to various bacteria early in life.
Lessons learned: Based on current knowledge, it is likely that the intestinal microbiota may contribute to the development of T1D. Additional research needs to be done, however, in order to identify the mechanisms leading to these causal relationships.