First gut bacteria may affect future ability to fight chronic diseases

Sept. 18 (UPI) -- Differences in the first microorganisms that arrive in the gut after birth, and their order of arrival, have a lasting impact on how gastrointestinal system looks later in life, according to a study.

Researchers at the University of Alberta believe serious chronic diseases can be warded off by adjusting the microbiome of gastrointestinal tract, which is unique to the body -- like fingerprints. Their findings were published Tuesday in the journal eLife.

"Each of us harbors a microbiome that is vastly distinct, even for identical twins," microbial ecologist Dr. Jens Walter said in a University of Alberta press release. "Microbiomes are important for our health, but they appear to be shaped by many unknown factors, so it's hugely important to understand why we are all different."

Problems with the gastrointestinal system have been linked to obesity, Type 2 diabetes, heart disease, inflammatory bowel disease, colon cancer, neurological disorders, autism and allergies.

"If we know what drives specific microbiomes in specific people, we can have a much more rational approach to potentially altering the microbiome, and developing strategies to address those diseases," Walter said.

Walter said studies have already shown that a person's genetics, diet, environment, lifestyle and physiological state account for less than 30 percent of the variation of the gut microbiome.

Researchers introduced distinct microbial communities from adult mice into the gastrointestinal tracts of young, genetically identical mice. Microbiomes in the adults were more similar to the microbiome first introduced into the mice. Despite using a cocktail of four different bacteria, the researchers repeatedly found that the first microbes showed the highest level of persistence and the strongest influence on the gut microbiome's development.

This research allows scientists to better understand how microbiomes might become disrupted, including through a caesarean section birth or antibiotic use.

"Having long-term persistence of microbes when they colonize in the gut early in life means that a health-promoting biome could potentially be established by introducing beneficial bacteria straight after birth," Walter said.