TUCSON, Ariz. – As she jumped to head a soccer ball during her junior year of college, Kelly Farrell collided skulls with a teammate. She later was diagnosed with a concussion, which proved to be severely debilitating.
“I had a lot of trouble concentrating in school and class,” said Farrell, a physical therapist and Tucson native, who experienced a constant headache for two days after her concussion. Even after the initial pain subsided, her headache was reactivated by noise, bright light and studying on her computer.
Each year, traumatic brain injuries such as concussions cause nearly 2.5 million visits to an emergency room. The most common problem associated with concussions is headache. In an effort to develop a treatment, researchers at the University of Arizona College of Medicine – Tucson collaborated in a preclinical study with scientists at Teva Biologics and the Mayo Clinic to identify the cause of post-concussion headaches and a possible therapy for the millions of patients who experience this pain each year.
With Edita Navratilova, PhD, assistant professor in the Department of Pharmacology, as lead author and Frank Porreca, PhD, associate head of the department, as a co-author, the group published its findings in Cephalalgia in September 2019.
The scientists investigated whether a drug that blocks a substance elevated in migraine patients, calcitonin gene-related peptide (CGRP), would alleviate the headache pain by modeling human concussion in mice and assessing post-injury pain sensitivity. Researchers administered the anti-CGRP treatment twice – two hours and then seven days after the injury – and found the two doses significantly reduced pain responses.
In addition to immediate or acute headaches, long-lasting or persistent post-traumatic headaches affect injured patients, Dr. Porreca said.
Researchers assessed persistent post-traumatic headaches in their mouse model. Bright light reactivated headaches in injured mice 14 days after injury but caused no headaches in healthy mice.
To prevent stress-induced headaches, scientists administered an additional drug dose before the bright-light stress. When administered before the stress, in addition to after the injury, the drug not only prevented the immediate headache but also prevented bright light from reactivating the headache.
Researchers concluded that CGRP may be the link between traumatic brain injuries and post-injury headaches.
“The sustained prevention of the actions of CGRP with an antibody treatment administered early after a mild traumatic brain injury prevents post-traumatic headache in our preclinical model, as well as the vulnerability for development of persistent post-traumatic headache,” Dr. Porreca said.
“The encouraging aspect is that we do have a mechanism which seems to be driving some aspect of the pain, and if treated at the right time in this preclinical model, it seems to be effective,” Dr. Porreca said. Although the timing and dosage of the drug would need to be adapted to humans in future clinical trials, he added, it appears immediate treatment is critical to the therapy’s success.
Story Submission by Brittany Uhlorn
214-783-7397 | Bforte2012@email.arizona.edu
NOTE: Photos available upon request.
About the University of Arizona College of Medicine – Tucson
The University of Arizona College of Medicine – Tucson is shaping the future of medicine through state-of-the-art medical education programs, groundbreaking research and advancements in patient care in Arizona and beyond. Founded in 1967, the college boasts more than 50 years of innovation, ranking among the top medical schools in the nation for research and primary care. Through the university's partnership with Banner Health, one of the largest nonprofit health care systems in the country, the college is leading the way in academic medicine. For more information, visit medicine.arizona.edu (Follow us: Facebook | Twitter | Instagram | LinkedIn).
About the University of Arizona Health Sciences
The University of Arizona Health Sciences is the statewide leader in biomedical research and health professions training. The UArizona Health Sciences includes the Colleges of Medicine (Tucson and Phoenix), Nursing, Pharmacy, and the Mel and Enid Zuckerman College of Public Health, with main campus locations in Tucson and the growing Phoenix Biomedical Campus in downtown Phoenix. From these vantage points, the Health Sciences reaches across the state of Arizona and the greater Southwest to provide cutting-edge health education, research and community outreach services. A major economic engine, the Health Sciences employs nearly 5,000 people, has approximately 900 faculty members and garners $200 million in research grants and contracts annually. For more information: uahs.arizona.edu (Follow us: Facebook | Twitter | YouTube | LinkedIn | Instagram).