A new study from the University of Minnesota, which was published in Cell Host & Microbe, has found that antibiotic use in infants changes the gut bacteria, and this leads to various diseases in adulthood. The gut microbes, which are called dysbiosis, are actually related to allergies, infectious diseases, and various autoimmune disorders that appear in adulthood. The changes in the gut bacteria can even lead to obesity later in life according to the new study.
Pajau Vangay, a student fellow from the Biomedical Informatics and Computational Biology program lead the study. Vangay also put together a model with how to measure healthy bacterial development in the guts of infants and younger children. The senior author of the study, Dan Knights, said that “Diseases related to metabolism and the immune system are increasing dramatically, and in many cases we don’t know why.” Knights is a computational biologist and assistant professor at the University of Minnesota’s Department of Computer Science and Engineering and Biotechnology Institute. There have been previous studies that have shown linked between antibiotic use and an unbalanced gut bacteria, with other studies showing how unbalanced gut bacteria is linked to diseases in adults. However, this is the first study to put all three of these things together, including how antibiotic use as an infant contributes to the changing gut bacteria, and this leads to the imbalances which lead to disease.
In terms of antibiotics, they are one of the most common types of medications given out to children, and end up being 25 percent of all medications prescribed to children. About one-third of these prescribed antibiotics are considered not needed, which is part of a bigger problem of over prescribing medications to people of all ages. There are all types of long-term and short-term effects from antibiotic use, including how it changes the bacteria in our bodies, and also changes the composition of the bacteria.
In this study, Knights and his colleagues put together a framework which showed how antibiotics could be interacting in the gut, which is how disease happens later in life. Antibiotics can eradicate a gut bacteria which helps the immune cells mature, which is how allergies occur later in life. We need these immune cells to be mature because it will help keep the allergies from turning into a problem, but because they are immature, the body cannot fight off the allergens. The immune system ends up staying messed up even when the bacteria returns to normal, which means there is long-term damage to these cells from the antibiotic use. When talking about obesity, the changes that occur in the gut as a result of antibiotics end up increasing the levels of a fatty acid that impacts metabolism.
Researchers were also able to examine how the gut bacteria develops, by being able to get within 1.3 months of an infant’s age just by looking at the maturity of the gut bacteria. This means that there could be a clinical test for children that would show if a microbiome is delayed due to antibiotic use or other medical conditions that could affect the gut bacteria. If doctors could perform this type of test, then they could intervene early before the changes in the gut lead to long-term health consequences, such as obesity or an autoimmune disease. This could also lead to a better way to treat changes to the gut bacteria, especially in the younger population which usually can bounce back quicker from negative changes in the body. More research will need to be done in order to determine just how much antibiotic use in infants is considered safe and how much it will take to negatively impact the gut bacteria.