Summary: A new study reports penicillin, when administered during pregnancy or during early years of life, can result in long-term behavioral changes.
Source: McMaster University.
In a landmark study, researchers at St. Joseph’s Healthcare Hamilton and McMaster University have found that providing clinical (low) doses of penicillin to pregnant mice and their offspring results in long-term behavioural changes.
These changes include elevated levels of aggression and lower levels of anxiety, accompanied by characteristic neurochemical changes in the brain and an imbalance in their gut microbes. Giving these mice a lactobacillus strain of bacteria helped to prevent these effects.
The study was published in Nature Communications and was funded by the United States Office of Naval Research.
“In this paper, we report that low-dose penicillin taken late in pregnancy and in early life of mice offspring, changes behaviour and the balance of microbes in the gut. While these studies have been performed in mice, they point to popular increasing concerns about the long-term effects of antibiotics,” says Dr. John Bienenstock, Director of the Brain-Body Institute at St. Joseph’s Healthcare Hamilton and Distinguished Professor at McMaster University.
“Furthermore, our results suggest that a probiotic might be effective in preventing the detrimental effects of the penicillin.”
Other studies have shown that large doses of broad-spectrum antibiotics in adult animals can affect behaviour. But there haven’t been previous studies that have tested the effects of clinical doses of a commonly-used, narrow-spectrum antibiotic such as penicillin on gut bacteria and behaviour.
“There are almost no babies in North America that haven’t received a course of antibiotics in their first year of life,” says Dr. Bienenstock. “Antibiotics aren’t only prescribed, but they’re also found in meat and dairy products. If mothers are passing along the effects of these drugs to their as yet unborn children or children after birth, this raises further questions about the long-term effects of our society’s consumption of antibiotics.”
A previous study in 2014 raised similar concerns after finding that giving clinical doses of penicillin to mice in late pregnancy and early life led to a state of vulnerability to dietary induction of obesity.
The research team will follow up their studies by analyzing the effects of penicillin on the offspring, if given only to the pregnant mothers. They also plan on investigating the efficacy of different types of potentially-beneficial bacteria in protecting offspring against the behavioural changes that result from antibiotic usage.
Funding: The research was funded by United States Office of Naval Research.
Source: Veronica McGuire – McMaster University
Image Source: NeuroscienceNews.com image is in the public domain.
Original Research: Full open access research for “Low-dose penicillin in early life induces long-term changes in murine gut microbiota, brain cytokines and behavior” by Sophie Leclercq, Firoz M. Mian, Andrew M. Stanisz, Laure B. Bindels, Emmanuel Cambier, Hila Ben-Amram, Omry Koren, Paul Forsythe & John Bienenstock Nature Communications. Published online April 4 2017 doi:10.1038/ncomms15062
Low-dose penicillin in early life induces long-term changes in murine gut microbiota, brain cytokines and behavior
There is increasing concern about potential long-term effects of antibiotics on children’s health. Epidemiological studies have revealed that early-life antibiotic exposure can increase the risk of developing immune and metabolic diseases, and rodent studies have shown that administration of high doses of antibiotics has long-term effects on brain neurochemistry and behaviour. Here we investigate whether low-dose penicillin in late pregnancy and early postnatal life induces long-term effects in the offspring of mice. We find that penicillin has lasting effects in both sexes on gut microbiota, increases cytokine expression in frontal cortex, modifies blood–brain barrier integrity and alters behaviour. The antibiotic-treated mice exhibit impaired anxiety-like and social behaviours, and display aggression. Concurrent supplementation with Lactobacillus rhamnosus JB-1 prevents some of these alterations. These results warrant further studies on the potential role of early-life antibiotic use in the development of neuropsychiatric disorders, and the possible attenuation of these by beneficial bacteria.
“Low-dose penicillin in early life induces long-term changes in murine gut microbiota, brain cytokines and behavior” by Sophie Leclercq, Firoz M. Mian, Andrew M. Stanisz, Laure B. Bindels, Emmanuel Cambier, Hila Ben-Amram, Omry Koren, Paul Forsythe & John Bienenstock Nature Communications. Published online April 4 2017 doi:10.1038/ncomms15062