एंटीबायोटिक्स : मस्तिष्क विकास को प्रभावित करती हैं !
Dark- side of Antibiotics : Influence Brain Development

Author : Dr. P. D.GUPTA

(Former Director Grade Scientist, Centre for Cellular and Molecular Biology, Hyderabad, India)


About 50 years back in the United States, most antibiotics are used not in humans, but in farm animals. Low doses of antibiotics helped animals, including cows, pigs, sheep, and chickens, grow bigger, faster. New research from Blaser, a microbiologist and infectious disease expert at Rutgers University, and his colleagues reveals that changes to the gut-brain axis from exposure to antibiotics early in life potentially play a role in brain development. 

In recent work published in iScience,( research journal of repute) Martin Blaser and his team showed that low doses of penicillin led to substantial changes to the intestinal microbiota in newborn mice, as well as gene expression changes in two key brain areas affecting    neurodevelopment. 

 Exposure to antibiotics early in life affects brain development in mice.

In the US, most children have received about three courses of antibiotic treatment by the time they turn 2 years old. In research published earlier this year with colleagues at the Mayo Clinic, Blaser showed that kids exposed to antibiotics have higher rates of asthma, obesity, type I diabetes, and celiac disease, among other chronic conditions. 

In the new research, Blaser and his colleagues used mice to find out whether antibiotics affected the early-life microbiota and gene expression in the amygdala or/and frontal cortex ( two key brain areas for emotional and cognitive function).

The researchers administered sub-therapeutic doses of penicillin to pregnant dams or to mouse pups from birth, while another group of mice did not receive any antibiotics. When the researchers assessed the microbiota of the pups at two weeks of age, they saw substantial differences between the pups that received antibiotics and those that did not. Mice treated with antibiotics lacked some microbial species that were dominant in the guts of mice that did not receive antibiotics. 

Blaser and his team then compared gene expression changes in the brain between the groups of pups. Pathway analysis revealed that pathways related to neuronal development and neuron fate commitment were upregulated in the mice that received antibiotics.  

“The differences in gene expression are very interesting and definitely worth further in-depth studies,”  

 . “I want to emphasize that this is very preliminary data,” Blaser said. “But it provides evidence that exposing young animals to antibiotics could have a direct effect on how their brains develop.”  Blaser noted that it is also possible that the antibiotic could have had a direct effect on the brain. They plan to dive into the mechanistic details with future experiments. 

“There are some kids who have ear infections that are terrible and should get antibiotics,” Blaser said. “And there are some kids who have extremely mild infections, and they should never get an antibiotic. Then there’s a big gray area in the middle.”

Take home lesson

Since the following recent observations were made

Low doses of continuous penicillin exposure altered mouse pups’ gene expression in brain areas associated with emotional and cognitive function.

Changes the composition of microbiota

Make certain bacteria resistant to all sorts of drugs and so cannot be killed.

Therefore one should be little coucious about antibiotics and “Antibiotics are wonderful drugs,” but we have to use them better because everyone’s using them as if there was no cost. (The author has his own study and views)