Early exposure to antibiotics kills healthy bacteria within the digestive tract and may cause asthma and allergies, a latest study demonstrates.

The study, published in Mucosal Immunology, has provided the strongest evidence up to now that the long-observed connection between antibiotic exposure in early childhood and later development of asthma and allergies is causal.

The sensible implication is easy: Avoid antibiotic use in young children each time you’ll be able to because it could elevate the chance of great, long-term problems with allergy and/or asthma.”

Martin Blaser, senior creator, director of the Center for Advanced Biotechnology and Medicine at Rutgers

Within the study, the researchers, who got here from Rutgers, Latest York University and the University of Zurich, noted that antibiotics, “amongst probably the most used medications in children, affect gut microbiome communities and metabolic functions. These changes in microbiota structure can impact host immunity.”

In the primary a part of the experiment, five-day-old mice received water, azithromycin or amoxicillin. After the mice matured, researchers exposed them to a standard allergen derived from house dust mites. Mice that had received either of the antibiotics, especially azithromycin, exhibited elevated rates of immune responses -; i.e., allergies.

The second and third parts of the experiment tested the hypothesis that early exposure to antibiotics (but not later exposure) causes allergies and asthma by killing some healthy gut bacteria that support proper immune system development.

Lead creator Timothy Borbet first transferred bacteria-rich fecal samples from the primary set of mice to a second set of adult mice with no previous exposure to any bacteria or germs. Some received samples from mice given azithromycin or amoxicillin in infancy. Others received normal samples from mice that had received water.

Mice that received antibiotic-altered samples were no more likely than other mice to develop immune responses to accommodate dust mites, just as individuals who receive antibiotics in maturity are not any more more likely to develop asthma or allergies than those that don’t.

Things were different, nonetheless, for the following generation. Offspring of mice that received antibiotic-altered samples reacted more to accommodate dust mites than those whose parents received samples unaltered by antibiotics, just as mice that originally received antibiotics as babies reacted more to the allergen than people who received water.

“This was a rigorously controlled experiment,” said Blaser. “The one variable in the primary part was antibiotic exposure. The one variable within the second two parts was whether the mixture of gut bacteria had been affected by antibiotics. All the things else concerning the mice was an identical.

Blaser added that “these experiments provide strong evidence that antibiotics cause unwanted immune responses to develop via their effect on gut bacteria, but provided that gut bacteria are altered in early childhood.”

Source:

Journal reference:

Borbet, T.C., et al. (2022) Influence of the early-life gut microbiota on the immune responses to an inhaled allergen. Mucosal Immunology. doi.org/10.1038/s41385-022-00544-5.