Pitt researcher studying how blue light can reduce inflammation
Exposing mice to 24 consecutive hours of bright blue light before surgery reduced inflammation that can lead to organ damage, according to findings released Monday by the University of Pittsburgh School of Medicine.
What the research means for humans remains to be seen.
Dr. Matthew Rosengart, a Pitt associate professor, hopes to find out. He recently received approval from the university's institutional review board to study light exposure in humans as a pretreatment form of therapy. Rosengart plans to study patients willing to bathe in blue light before undergoing liver resections and treatment for sepsis, a severe bodily reaction to an infection.
During the recent study, Rosengart and a team exposed more than 100 mice to red light, white fluorescent light and high-intensity blue light for 24 hours before kidney or liver surgery. The results, described by Rosengart as “surprising,” showed that blue light reduced a type of white blood cell involved in inflammation.
The blue light additionally prevented dying cells from releasing a protein that can trigger organ-damaging inflammation. The technique did not work on blind mice, proving that blue light entered the eye pathways instead of through the skin.
Rosengart explained that blue light is similar to daylight, and daytime is when the body is most primed to respond to harm.
The National Institutes of Health funded the research, which lasted five years.
“In animals and humans, light enters through the eye and impinges upon cells that are particularly sensitive to light rich in blue spectrum,” Rosengart wrote in the scientific journal, Proceedings of the National Academy of Sciences. “Thus, we believe that modulating the spectrum of light will enable us to regulate these protective mechanisms, and thereby, treat certain diseases. Our current data supports this hypothesis.”
The study points out that mice are nocturnal creatures, so there's potential that people won't react in the same manner.
“There's long been evidence suggesting that light and circadian rhythms profoundly influence our biology, and specifically the physiological response to stress,” Rosengart said. “So while we were expecting to find some correlation with light spectrum and the immune response, we were not expecting results quite so striking.”
In studying people, he said, he'll search for the ideal spectrum; maybe 24 hours is too much exposure, or not enough. He initially hopes to enroll 10 participants.
“I'm very passionate about this,” he said. “The data is compelling, and I look forward to trying it in humans.”
Ben Schmitt is a Tribune-Review staff writer. Reach him at 412-320-7991 or bschmitt@tribweb.com.
