As an audiologist, Kathleen Campbell grew frustrated with the lack of treatments for people with hearing loss caused by excessive and loud noise.
“You can put hearing aids on but it is not the same,” she said. “You can’t fully correct them.”
After more than 25 years in a clinic, Campbell moved into audiology research full time at the Southern Illinois University School of Medicine in Springfield. She was recently awarded a $ 1.2 million, three-year grant from the U.S. Department of Defense for her team’s work on drug therapies to prevent and treat noise-induced hearing loss, particularly in military settings.
More than one-third of service men and women have some degree of hearing loss when they retire from the military. In addition to disadvantages in the field caused by hearing loss, it can also lead to post-traumatic stress disorder, anxiety and depression.
Campbell’s work involves the use of an antioxidant called D-methionine, a component of fermented protein that is found in yogurt and cheese. The antioxidant, in concentrated doses, has been found to improve some forms of hearing loss and even prevent hearing loss before the exposure to noise.
“We’ve been able to show in animal studies that if we give it before and after noise exposure, that we can get pretty full protection from noise-induced hearing loss,” Campbell said.
Campbell and her colleagues will continue their studies by looking at the effects of varying dosages of D-methionine on animal subjects exposed to different noises. They have already found that the drug can be given up to seven hours after the noise is experienced and still be effective.
“It doesn’t mean it’s going to work for long-standing hearing loss, but it does mean that in the early stages, you could intervene and keep it from becoming permanent,” she said.
The research will then move into determining if even more time can elapse before the drug is given and the hearing loss becomes permanent.
Human clinical trials with the U.S. Army are in the early planning stages, Campbell said.
Campbell’s father lost some hearing while serving on a Navy carrier during World War II. Other members of her family are disabled Army veterans.
“My heart is in getting something to prevent noise-induced hearing loss in our troops,” she said. “It makes them more vulnerable in the battlefield if they can’t detect the enemy.”