New research raises possibility of treating trauma by manipulating gut bacteria

Studies at University College Cork have shown that trillions of bacteria within the gastrointestinal tract regulate fear responses and modifies the brain function of adult mice

Studies carried out with mice show their gut bacteria trigger fear via a region of the brain known as the amygdala – and it is believed this may also happen in humans. Photograph: Istock

Studies carried out with mice show their gut bacteria trigger fear via a region of the brain known as the amygdala – and it is believed this may also happen in humans. Photograph: Istock

 

 

We may soon be able to control fear by manipulating the mix of bacteria in our gut, new research suggests. It raises the possibility of successfully treating conditions such as Post Traumatic Stress Disorder (PTSD) by controlling the type of bacteria in a patient’s gastro-intestinal tract.

Studies carried out with mice show their gut bacteria trigger fear via a region of the brain known as the amygdala – and it is believed this may also happen in humans. It is hoped that scientists will be able to manipulate gut bacteria to control the fear response in humans.

Research at University College Cork (UCC) has shown that the microbiome – trillions of bacteria within the gastrointestinal tract – regulates fear responses and modifies the brain function of adult mice.

“The amygdala is a part of the brain shown to be important for the expression of fear and anxiety in both mice and men,” explained Dr Gerard Clarke of the APC Microbiome Institute at UCC. The research findings are published in Nature Journal Molecular Psychiatry. The institute is funded by Science Foundation Ireland.

Fear response

“The fact that we can pinpoint this to the amygdala in these animals is very important,” he added. “What we did not know is that we could target the gut bacteria to control the brain response in a mouse.

“Our next step is to see if we can control the fear response by manipulating the bacteria in the gut of the mouse,” he said. “We are at a very early stage in animal testing, but down the road the hope is that we would be able to manipulate the gut bacteria to try to control excessive fear such as in the case of PTSD.

Understanding the factors that regulate fear and fear-associated memories was “an important step towards developing therapies for disorders where excessive brain responses to fear memories are manifested, such as PTSD”, Dr Clarke added.

The role gut bacteria play in our health and wellbeing is increasingly the focus of research. “Perhaps most surprising of all is the realisation that gut bacteria influence brain function and behaviour,” Dr Clarke said.