Men as Mice

The outlook for those who’ve endured numerous sports-related concussions is getting brighter as researchers continue to probe the brains of former professional football players to learn the full extent of damage from repeated head trauma. 

The lasting effects of head trauma came to light with the recent suicide of San Diego Chargers legend Junior Seau. Earlier this month, researchers from the National Institutes of Health released their findings after examining Seau’s brain tissue. They discovered that he'd had chronic traumatic encephalopathy (CTE)—a condition seen in many retired NFL players—which has been linked to memory loss, depression, personality changes, progressive dementia, and other serious disorders.

While many athletes in contact sports—namely football and women’s soccer—are at a high risk of developing CTE, until recently there was no way to determine how the brain handled these injuries in the long term.

Now, a research team at UCLA has used a common brain-imaging tool to identify abnormal proteins in the brains of five retired NFL players. These living legends helped researchers discover proteins associated with Alzheimer’s disease that in the past could only detected during an autopsy. The research was released Tuesday in the American Journal of Geriatric Psychiatry.

Searching for "Tangles" in the Brain

Previous research has linked CTE to the accumulation of tau proteins, which are believed to cause the “tangles” in brain fiber associated with progressive dementia and Alzheimer’s disease.

“Early detection of tau proteins may help us to understand what is happening sooner in the brains of these injured athletes,” lead study author Dr. Gary Small, UCLA's Parlow–Solomon Professor on Aging and a professor of psychiatry and biobehavioral sciences at the Semel Institute for Neuroscience and Human Behavior at UCLA, said in a news release. “Our findings may also guide us in developing strategies and interventions to protect those with early symptoms, rather than try to repair damage once it becomes extensive.” 

For this study, UCLA researchers recruited five retired NFL players 45 years old or older. All had a history of concussions and were experiencing some type of cognitive or mood disorder.

The players were tested using an imaging tool typically used to monitor changes in Alzheimer’s patients. The players were injected with a marker known as FDDNP that attaches to abnormalities in the brain, such as tau proteins. When the players’ brains were viewed during a positron emission tomography (PET) scan, researchers were able to see where tau proteins had accumulated.

The scientists found that the NFL players had elevated levels of FDDNP in the amygdala and subcortical regions of the brain when compared with healthy men of a similar age and education level. Players who experienced more concussions had higher FDDNP levels in those regions, which control learning, memory, behavior, emotions, and other mental and physical functions, researchers said.

Besides the brain scan, the former players were given tests to rate their cognitive function and overall mental health. Three players had mild cognitive impairment, one had dementia, and another had normal mental function. 

Wayne Clark, a quarterback with the San Diego Chargers and Kansas City Chiefs in the 1970s, was the player studied with normal brain function.

“I hope that my participation in these kinds of studies will lead to a better understanding of the consequences of repeated head injury and new standards to protect players from sports concussions,” he said.

The "Holy Grail" of CTE Research

This window into the brains of living legends could prove extremely beneficial for screening those at the highest risk of CTE and other traumatic brain injuries. 

Earlier research of 3,400 retired football players showed that they have a slightly greater risk of developing Alzheimer’s. Numerous cross-studies are currently delving into this connection, as well as the practical implications these findings hold for the treatment of progressive brain trauma.

“It is the holy grail of CTE research to be able to identify those who are suffering from the syndrome early, while they're still alive. Discovering the effects of prior brain trauma earlier opens up possibilities for symptom treatment and prevention,” said study author Dr. Julian Bailes, chair of the department of neurosurgery at NorthShore University HealthSystem in Evanston, Ill. 

Besides retired professional football players, researchers hope this kind of testing could prove beneficial for others at risk of traumatic brain injury: military personnel, auto accident victims, etc.

This could also prove vital as more children become involved in high-risk sports—skateboarding, BMX biking, and the like—besides football and other traditional sports. The Institute of Medicine announced earlier this month that it will be launching the largest study to date on the impact of sports-related injuries in young people.

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