A new study suggests that repeated head injuries like concussions, may reactivate a dormant virus in the brain, increasing the risk of Alzheimer’s disease (AD). Researchers found that even mild brain trauma can trigger a chain reaction, leading to memory loss and cognitive decline.
In previous studies, researchers showed that common viruses like herpes simplex virus type 1 (HSV-1) and varicella zoster virus (VZV) play a role in AD development. HSV-1 is known as the cold sore virus. VZV causes chickenpox and shingles. These viruses can remain dormant in the brain for years, only to reactivate under certain conditions associated with Alzheimer’s.
HOW HEAD INJURIES REACTIVATE DORMANT VIRUSES
The latest research, published in Science Signaling, used a 3D bioengineered human brain tissue model to examine the effects of physical trauma on brain cells. The team exposed the brain tissues to mild blows, mimicking concussions. This triggered the reactivation of HSV-1, causing inflammation. This led to the build up of beta-amyloid plaques. It also led to formation of tau proteins, all of which are linked to Alzheimer’s.
THE DISCOVERY OF POTENTIAL TREATMENT
One key finding from the study is that blocking an inflammatory molecule, Interleukin-1 beta (IL-1β), helped prevent many of the harmful effects caused by the reactivation of HSV-1. This discovery introduces potential new treatments for people at high risk of Alzheimer’s. Repeated head injuries put these individuals at risk of developing Alzheimer’s.
INSIGHTS FROM A LEADING EXPERT
Professor Ruth Itzhaki led the research. She has been studying the potential link between HSV-1 and Alzheimer’s for over 30 years. She noted that head injuries have long been recognized as a risk factor for Alzheimer’s and dementia. This study is the first to show a clear mechanism behind that process.
“We have shown that head injuries can reactivate the HSV-1 virus. This reactivation leads to the very changes we see in Alzheimer’s patients,” said Professor Itzhaki. “Understanding the risk factors and mechanisms behind dementia is crucial for developing early treatments and preventative measures to combat Alzheimer’s.”
A STEP TOWARD NEW TREATMENTS
This groundbreaking research paves the way for new treatments. These treatments aim to protect against neurodegeneration. This is especially important for those at high risk due to repeated concussions linked to Alzheimer’s. The team hopes their findings will contribute to the development of targeted therapies that can intervene before the disease progresses.
The full study, Repetitive Injury Induces Phenotypes Associated with Alzheimer’s Disease by Reactivating HSV-1 in a Human Brain Tissue Model, is available in Science Signaling.
