Childhood gut bacteria key to happy hormone

Irish scientists have found that the happy hormone — serotonin — is regulated by the amount of gut bacteria in childhood.

The study has implications for young children given antibiotics that wipe out gut bacteria, and suggests that taking probiotics with the medication might be useful.

Scientists at the Alimentary Pharmabiotic Centre in University College Cork used a bacteria-free mouse model to prove their point.

Lead author Gerard Clarke said the research showed the effect of anti-biotics, diet, or infection on gut microbiota could have a profound knock-on effects on brain function.

Of particular concern is that many of the central nervous system changes, especially those related to serotonin, could not be reversed.

Serotonin is a major chemical involved in the regulation of mood and emotion, and is altered in times of stress, anxiety and depression. Most clinically effective anti-depressant drugs work by targeting the neurochemical.

“We’re really excited by these findings,” said Mr Clarke. “Although we always believed that the microbiota was essential for our general health, our results also highlight how important our tiny friends are for our mental well being.”

The research, published in the leading international journal Molecular Psychiatry, also found there was a more marked effect on males.

Scientists found many of the central nervous system changes could not be rev-ersed when they colonised the animals with bacteria prior to adulthood.

Senior author and head of the Department of Anatomy and Neuroscience at UCC, Prof John F Cryan, said the research opened up the “intriguing opportunity” of developing unique microbial- based strategies to treat brain disorders.

Prof Cryan said future research would try and determine the good bacteria that regulates serotonin.

Meanwhile, researchers at University College Dublin have found that simply going out for a coffee or chatting to a friend can alleviate symptoms of depression.

More than 100 adults, who were already receiving conventional treatment for mental health problems, were given additional supports to increase their social activities over a nine-month period.

All of the participants in the study, funded by the Health Research Board, were encouraged to take part in a social activity for at least two hours every week.

At the beginning of the study, 20% of participants had no contact with friends, 33% never had contact with neighbours, 50% never attended social groups, and 35% were living alone.

When the study concluded, all of the particip-ants reported feeling better about themselves and having more confidence to socialise in their community.


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