Animal research published in the journal Science showed that exposure during childhood to normal bacteria found in the gastrointestinal (GI) tract may protect against developing autoimmune diseases such as diabetes, multiple sclerosis and lupus. The study also provides theories on why certain autoimmune diseases, including lupus, are more common among females.
Researchers from The Hospital for Sick Children (SickKids) found that when female mice at high risk for developing the autoimmune disease, type 1 diabetes were exposed to normal bacteria taken from the gut of adult male mice, they were strongly protected against the disease. Only 25% of those female mice given the gut bacteria developed diabetes.
A second unexpected finding was the effects of these treatments on sex hormones. Levels of the male sex hormone testosterone increased among the young female mice given the bacteria from adult male mice. Researchers found that this hormone was necessary for the bacteria to protect against diabetes. But how the bacteria affects the levels of testosterone or how the hormone protects against autoimmunity is not clear. Lead researcher Dr. Jayne Danska, Senior Scientist in Genetics & Genome Biology at SickKids noted the study may lead to exploration of how altering this bacteria might prevent or treat autoimmune disease.