How can a blow to the head wake up dormant viruses in our body?

Some discoveries of science are so hard to believe that they seem like lies. This is the situation that emerged in the research Severe head trauma can reactivate dormant viruses in our bodycauses serious consequences.

This finding came from a study conducted by researchers at Tufts University and the University of Oxford, which found that: Repeated head trauma may reactivate herpes virus simplex type 1 (HSV-1) remains dormant in the brain and causes a range of damage associated with Alzheimer’s disease.

The relationship between trauma and virus

The study used stem cell “mini-brains” and found that herpes simplex virus 1 (HSV-1) infection, which had already been “turned off” by the immune system, could be reactivated when there was unexpected disruption of brain tissue. . The research was published in the scientific journal January 2025. Science Signal.

The goal was to test what would happen if a model of brain tissue was subjected to some type of physical disturbance, such as a concussion, according to Dana Cairns, a biomedical engineer at Tufts University. The question to be investigated was: In case of any trauma, does HSV-1 “wake up” and initiate the process of neurodegeneration?

Surprisingly, scientists discovered that the answer is yes. Although the minibrains are not perfect representations of a real brain, they served as models for observing how brain tissue typically responds when repeated pulses of light come to the head.

Research findings

One week after performing the experiment with the lesion, Researchers began to notice the formation of protein clumps and tangles in brain tissue that are a hallmark of neurodegenerative diseases such as Alzheimer’s disease. Other cells showed damage linked to neuroinflammation, which is also linked to the condition.

In recent years, scientists in the field of neuroscience have begun to see that traumatic brain injuries, including chronic traumatic encephalopathy (a degenerative brain disease caused by repeated blows to the head or blast injuries), are important factors in the development of the following brain injuries. neurodegenerative diseases. Additionally, chronic inflammation, which can result from even mild head trauma, may also play a role in cumulative brain damage.

Researchers still don’t know exactly how this whole process happens, but there are new studies that observe an association with viruses such as herpes simplex virus (HSV), which can trigger neurodegeneration processes and double a person’s chances of developing dementia. future.

A 2008 study found that HSV-1 was present in 90% of the protein plaques found in the brains of people who died of Alzheimer’s. Viral DNA was found precisely within these plaques.

To deepen this knowledge, researchers at Tufts and Oxford analyzed isolated brain slices. They observed that those infected with latent HSV-1 began secreting less of the excitatory neurotransmitter glutamate after sustaining a physical injury.

“Our results showed that trauma caused reactivation of latent HSV-1 in our 3D brain model, and if the injury was repeated, the damage was much greater than that occurring after a single blow,” the team said. Therefore, researchers’ current hypothesis is that this virus, which is very common among humans, is a contributing factor to the development of dementia.

Dangers of head trauma

The relationship between head trauma and dementia is still not entirely clear, but recently published study may shed new light on the effects of head trauma. It is worth remembering that repeated blows to the head are very common in contact sports such as American football, rugby and boxing.

Therefore, scientists noticed a high incidence of neurodegenerative diseases in former athletes. The effects of traumatic brain injuries (TBIs) can include behavioral problems, mood problems, and impairments in cognitive function. Typically these diseases tend to worsen over time.

There is now a possibility of better understanding the relationship of these problems with the presence of hidden viruses in the brain. In previous research, Carns found evidence that activation of HSV-1 from dormancy triggers the characteristic symptoms of Alzheimer’s disease. “In this study, another virus (chickenpox) created the inflammatory conditions that activated HSV-1,” he said.

HSV-1 is a very common virus found in the bodies of a large proportion of the global population. It is known as the cause of herpes and can cause lifelong latency in the body. HSV-1 is estimated to infect more than 64% of people, while the varicella-zoster virus responsible for chickenpox and shingles is present in 95%. These viruses can settle in the brain and remain dormant in neurons, only to become active again when a situation arises for this to occur.

“Understanding the risk factors for dementia and Alzheimer’s and the mechanism by which they develop is important so that we can target treatment and prevention as early as possible,” said researcher Ruth Itzhaki from the University of Oxford.

In fact, our organism works in ways we could never imagine. Want to learn more about scientific discoveries in healthcare? So keep following TecMundo To always be informed about the latest news!