Scientists probe how traumatic brain injury might lead to dementia.
The anesthetic drug xenon increases life expectancy and prevents long-term cognitive impairment following a traumatic brain injury (TBI) in mice, according to a new study out of Imperial College London.
“The finding that only a short treatment with xenon can have beneficial effects on cognition, survival, and brain damage almost two years later suggests that xenon might in future prevent cognitive decline and improve survival in human TBI patients,” said lead researcher Dr. Robert Dickinson.
How traumatic brain injury leads to dementia
Traumatic brain injuries are the leading cause of death and disability in people under 45. The primary injury, caused by the force of impact to the brain (from a fall or car accident, for example), is followed by a secondary injury that occurs in the minutes, hours or days after the accident. This secondary injury is what leads to the mental and physical disabilities associated with brain trauma.
People who go on to survive the initial injury have an increased risk of Alzheimer’s disease and other types of dementia later in life. TBI patients also have a lower life expectancy.
Related: How Does Traumatic Brain Injury Affect Dementia Risk?
Brain-Injured Mice Treated With Xenon Gas Show Few Signs of Brain Damage
Now, researchers have found evidence that administering xenon gas shortly after a traumatic brain injury prevents early death and long-term cognitive issues and protects against brain tissue degeneration in mice.
This is the first study to track the life-long effects of xenon in mice with TBIs. Previous shorter studies by the same researchers showed that xenon curbed early brain damage and improved long-term motor skills, but hadn’t looked into long-term cognitive function.
This most recent study, published in the British Journal of Anaesthesia found that the TBI xenon group of mice had the same life expectancy as the control group that didn’t suffer any traumatic brain injuries.
Mice with traumatic brain injuries that didn’t receive xenon gas developed late-onset cognitive damage, whereas those that were treated with xenon did not.
Xenon treatment prevented the loss of brain cells in the hippocampus, where learning and memory occur, and reduced brain inflammation believed to be involved in Alzheimer’s disease and other dementias.
Related: How Many Hits to the Head Before Dementia-Like Damage Occurs?
More Research Needed on Neuroprotective Benefits of Xenon
Xenon is currently used as a human anesthetic; it has very few side effects. The gas can be easily administered via inhalation in emergency room settings, note the researchers.
A 2016 review in the journal Cell Death and Disease backs up xenon’s neuroprotective claims. Animal studies have shown that it protects and restores the brain after events such as brain ischemia (lack of blood flow to the brain) and traumatic brain injuries. Researchers suspect xenon works by limiting the stimulation of glutamate receptors (NMDA) after a traumatic event.
Studies in humans are needed to see if the protective effects of xenon can be replicated in people with a traumatic brain injury.
Read Next: Decades Later, Traumatic Brain Injury Still Heightens Chance of Dementia
