Public Release: 

Unwanted impact of antibiotics broader, more complex than previously known

Oregon State University

CORVALLIS, Ore. - Researchers at Oregon State University have discovered that antibiotics have an impact on the microorganisms that live in an animal's gut that's more broad and complex than previously known.






"Just in the past decade a whole new universe has opened up about the far-reaching effects of antibiotic use, and now we're exploring it," said Andrey Morgun, an assistant professor in the OSU College of Pharmacy. "The study of microbiota is just exploding. Nothing we find would surprise me at this point."

This research used a "cocktail" of four antibiotics frequently given to laboratory animals, and studied the impacts.

"Prior to this most people thought antibiotics only depleted microbiota and diminished several important immune functions that take place in the gut," Morgun said. "Actually that's only about one-third of the picture. They also kill intestinal epithelium. Destruction of the intestinal epithelium is important because this is the site of nutrient absorption, part of our immune system and it has other biological functions that play a role in human health."




Morgun and Schulzhenko's research group also found that one of the genes affected by antibiotic treatment is critical to the communication between the host and microbe.

"When the host microbe communication system gets out of balance it can lead to a chain of seemingly unrelated problems," Morgun said.


This research also developed a new bioinformatics approach named "transkingdom network interrogation" to studying microbiota, which could help further speed the study of any alterations of host microbiota interactions and antibiotic impact. This could aid the search for new probiotics to help offset antibiotic effects, and conceivably lead to systems that would diagnose a person's microbiome, identify deficiencies and then address them in a precise and individual way.

Healthy microbiota may also be another way to address growing problems with antibiotic resistance, Morgun said. Instead of trying to kill the "bad" bacteria causing an illness, a healthy and functioning microbiota may be able to outcompete the unwanted microbes and improve immune function.


Collaborators on this research were from the OSU College of Pharmacy; OSU College of Veterinary Medicine; OSU College of Science; the National Cancer Institute; University of British Columbia; University of Maryland School of Medicine; and the National Institutes of Health.
