Compound in plastics can worsen migraines

Researchers at the University of Kansas Medical Center have shown that a compound frequently found in plastics, Bisphenol A (BPA), can worsen migraine headache-related symptoms. The findings suggest that migraine sufferers might be able to reduce the frequency and severity of their headaches by changing their diets.

Nancy Berman, Ph.D., a professor of anatomy and cell biology at KU Medical Center, is one of the country's leading experts on migraine. Building on her previous research showing a connection between migraines and the hormone estrogen, Berman developed a way to test potential headache drugs in laboratory rats. The discovery was significant because, while potential treatments are frequently tested first in animals, there had been no definitive test to determine whether a rat had a headache.

"Currently, migraine has no specific biomarker test, and analysis of symptoms is the only way to diagnose this disorder," Berman says. In conjunction with Kenneth E. McCarson, Ph.D., and the staff of the KU Medical Center's Rodent Behavior Facility, she discovered that rodents with headaches behave much the same as humans: they avoid light, sound, grooming, and routine movements. These studies open the door for testing new treatments for migraine, and for identifying factors that may worsen it.

BPA is considered an "environmental estrogen" because it mimics the hormone estrogen in the body. It is estimated that greater than 90 percent of the U.S. population has BPA in their bodies. The effect of BPA exposure on cancer has been widely studied, but little is known about the role of BPA in worsening migraine and other pain syndromes.

Berman and Lydia Vermeer, Ph.D., a postdoctoral fellow in Berman's lab, studied the behavior of rats after they were exposed to BPA. "We hypothesized that BPA exposure would activate estrogen receptors, exacerbating migraine symptoms," says Vermeer, lead author on the study, which was recently published in the journal Toxicological Sciences. In a group of rodents with migraines, those that had been exposed to BPA showed significantly worsened migraine symptoms than those that had not.

"This is an entirely new direction for the field of migraine," says Berman. The scientists now believe that a change in diet might provide some relief for migraine sufferers, who make more than 68 million visits to physicians' offices or emergency rooms in the United States each year.

The authors note that a small clinical study conducted by Ruthann A. Rudel and colleagues at the Silent Spring Institute in Newton, Mass., in 2011, used a "fresh foods" diet that eliminated all plastic and canned packaging. It demonstrated a 66 percent decrease in urinary BPA in patients after just three days. "These findings, combined with our results, suggest that a clinical trial to decrease BPA exposure and levels in migraine sufferers may reduce the frequency and severity of headaches and may increase the quality of life for migraine sufferers," Vermeer says.

"There are no new drugs in the pipeline, and you don't need Food and Drug Administration approval to change your diet, so this could be really helpful to a lot of migraine sufferers," Berman says. 

This work was supported by the National Institute of Environmental Health Sciences (NIEHS), a division of the NIH, grant number 2T32ES007079-31, and by the Kansas IDeA Network of Biomedical Research Excellence (K-INBRE) which is funded by the National Institute of General Medical Sciences, a division of the NIH, grant number P20GM103418.