Antibiotics may aid TBI recovery, study suggests

Short-term antibiotic treatment reduced brain inflammation after traumatic brain injury by altering gut bacteria in animal models, a recent study suggests.

Two beneficial bacteria, Parasutterella excrementihominis and Lactobacillus johnsonii, were identified as drivers of cell repair and may also help regulate inflammation in other parts of the body.

Researchers found that administering antibiotics after injury reduced lesion size, meaning areas of damaged brain tissue, and limited cell death.

The work was led by Sonia Villapol, associate professor in the department of neurosurgery at Houston Methodist.

She said: “We found that antibiotic treatment following TBI can reduce harmful gut bacteria, decrease lesion size and limit cell death.

“Our results support a gut–brain mechanism in which microbiome changes influence peripheral immunity and, in turn, neuroinflammation after TBI.”

Around 70 per cent of immune system regulation is linked to the gut microbiome, the community of bacteria living in the digestive system.

When this balance is disrupted, communication between the brain and gut can affect other organs.

“Our brains are constantly sending signals to the rest of our bodies. Following a traumatic brain event, those signals can get scrambled and disrupt other organs, including our digestive system,” Villapol said.

“If the gut stays out of balance, the brain may have a harder time healing.”

There are an estimated 4m traumatic brain injuries each year in the US.

Research suggests that gut microbiome imbalance after TBI may contribute to neurodegenerative diseases such as Parkinson’s, Alzheimer’s and dementia.

Villapol’s lab is investigating neuroprotective treatments designed to reduce inflammation linked to neurodegenerative disease.

Neuroprotection refers to approaches intended to prevent damage to brain cells.

“If we can break neuroinflammation in the acute or chronic stage, we can reduce the risk of developing Alzheimer’s or dementia,” Villapol said.

The next phase of the research will focus on bioengineering Parasutterella excrementihominis and Lactobacillus johnsonii to develop targeted therapies aimed at reducing neuroinflammation, which refers to inflammation affecting the brain and spinal cord.