BALTIMORE — Jonathan Martin believes he does most things right.
He was a former offensive tackle with the Miami Dolphins and San Francisco 49ers, but he retired at age 26 before the subconcussive headbutts typical of his position could do more damage. He lost 50 pounds, took up yoga and meditation and, after jumping from job to job, enrolled in an MBA program at the University of Pennsylvania.
But Martin, now 32, thinks he may have suffered dozens of concussions playing football and has had bouts of anxiety and depression, all symptoms linked to chronic traumatic encephalopathy, the degenerative brain disease that plagues football players and was found posthumously in a former teammate who died. died on 26.
Martin’s concerns led him to participate in a study at Johns Hopkins University in 2019 that could help scientists develop treatments for the symptoms and diseases associated with brain trauma and CTE.
“I wanted to be at the forefront of a solution,” said Martin, who was the target of a teammate’s bullying that made headlines in 2013. “There should be more focus on head injuries. I want to know how to keep my mind lubricated.”
The study, now completing its second phase, examines why the brains of former footballers years after the athletes stopped playing, continue to work overtime to repair themselves. Using PET scans, researchers track brain cells known as microglia, which remove and repair damaged neurons. Those cells are usually active after trauma, including concussion, and diminish as the brain heals.
“The microglia and the molecule they work with are basically the sanitation workers of the brain,” said Jonathan Lifshitz, the director of the Translational Neurotrauma Research Program at Phoenix Children’s Hospital, who is not involved in the research at Johns Hopkins. “They’re like FEMA: they’re very alert and when they’re needed, they come in and act.”
Head Injury and CTE in Sports
The permanent damage caused by brain injuries in athletes can have devastating consequences.
Active microglia are normally welcomed because they help the brain repair itself, but if they remain active so long after the trauma has ended, it could mean that other problems arise.
While the activity of those microglia has been found in others who have suffered brain trauma — people in car accidents, for example — those groups can be difficult to find and track for the duration of a time-consuming study. However, NFL players are a discreet group that is easy to identify and, like Martin, eager to participate.
dr. Jennifer Coughlin, an associate professor at Johns Hopkins University School of Medicine and the study’s principal investigator, first observed the overwork of the regenerating brain cells in a pilot of the study that began in 2015. Testing four active NFL players and 10 former professionals whose careers ended within 12 years, Coughlin’s team found higher levels of a biomarker that increases as microglia activity increases.
That chronic activity, she said, could be a sign that players are at risk for developing other problems associated with brain trauma, such as impaired memory, mood disorders or Alzheimer’s disease.
“We want to know whose brain is healing and why,” Coughlin said. “That could inform new treatments.”
To gain clarity, Coughlin and the researchers focused the second phase of the study on younger former players, who were less likely to have vascular disease or other indications that could independently cloud the interpretation.
Martin, who had battled depression since the plague scandal that got worse after leaving the NFL, wondered if football played a part. He contacted the Concussion Legacy Foundation to learn more about possible ties, and the group referred him to the Johns Hopkins study.
“Based on some of my behavior, the question occurred to me, is there something wrong with me other than just normal depression?” said Martin. “Anyone who plays football knows that hitting your head is not good for you.”
He was first examined in late 2019 and, after the investigation was delayed due to the coronavirus pandemic, returned to Baltimore in March for two days of follow-up testing.
On the first day, Martin answered questions about changes in his cognitive abilities and mental health since his first visit. The next morning, he returned for a PET scan, an imaging test that would track his brain activity by following a chemical injected into his arm.
During the 90-minute scan, Martin meditated to get over the claustrophobia that his head was in a tight-fitting metal cylinder for so long. Karen Edmonds, a nuclear medicine doctor, provided him with a wet fungus that, once cured, would keep Martin’s head still.
“Once it’s molded, it fits like a glove,” she said.
An anesthesiologist then placed a catheter in Martin’s left arm for the approximately 35 blood samples that would be collected during the scan.
Once in the PET scan room, Martin lay on his back on a table with a blanket draped over him and was shoved backwards until his head was inside the scan tube. Then the tracer was injected into his right arm and Edmonds saw the progress on a monitor.
“The goal is to see how much of the radiotracer lights up in the brain,” Edmonds said. “There’s only one dose at the beginning and then we check how quickly it deteriorates.”
After the test ended, Edmonds pulled the table with Martin out of the tube. “I have claustrophobia, but I just breathed through it,” Martin said. “You’re definitely bored, but it’s finite.”
Coughlin arrived to remove the arterial catheter, which took about 15 minutes.
She has tested 22 former NFL players and 25 other athletes so far, and she hopes to test a total of 70 participants, better to isolate possible factors that trigger brain activity. Genetics, other medical conditions, the player’s position on the field and when he started playing football can all contribute, Coughlin said.
“This will allow us to analyze what factors there are for people with persistent brain injuries,” she said.
Even with the participation of Martin and other players, Johns Hopkins’ research is still relatively small and only beginning to understand how traumatized brains behave. But it has the potential to identify the early onset of diseases and symptoms associated with head trauma, not only in football players, but also in people who have previously been involved in bicycle accidents, car crashes and other collisions.
“Right now, there’s no really good way to diagnose Alzheimer’s or Parkinson’s disease early,” said Jay Alberts, a neuroscientist at the Cleveland Clinic’s Center for Neurological Restoration. “It’s so important to be able to raise a yellow flag or a red flag.”
The study is blind, which means that Martin and the other participants are not told the results of their individual tests. But Martin said getting involved was as much about helping others as it was themselves.
“It’s all part of the research I’m passionate about to make the game better,” he said.