University of Pittsburgh researchers close to preventing tinnitus

University of Pittsburgh researchers say they are close to finding a way to prevent tinnitus, a debilitating condition that affects hearing.

Associate professor Thanos Tzounopoulos of the Pitt School of Medicine said he and his team treated mice with a federally approved epilepsy drug while exposing them to loud noises. The treated mice did not develop tinnitus, he said; half of the untreated mice did.

“That was quite exciting and still is,” Tzounopoulos said. “It opens up a lot of interesting possibilities. Millions of people are disabled by tinnitus. They cannot work, they cannot sleep. It's a very important problem.”

Tzounopoulos said his team will work with researchers from Pitt's School of Chemistry to develop a drug that specifically targets tinnitus. Human trials could start soon, he said.

“Such a medication could be a very helpful preventive strategy for soldiers and other people who work in situations where exposure to very loud noise is likely,” Tzounopoulos said. “It might also be useful for other conditions of phantom perceptions, such as pain in a limb that has been amputated.”

Five to 15 percent of Americans suffer from tinnitus, which has no cure. They hear phantom sounds, including whistling, clicking and roaring.

During research that spanned more than three years, Tzounopoulos and his team sedated mice and exposed them to a 116-decibel noise — the equivalent of an ambulance siren — for 45 minutes. Thirty minutes into the test and twice daily for the next five days, the team injected half of the mice with the epilepsy drug retigabine. The mice treated with retigabine did not develop tinnitus.

The team's findings were published online Monday in Proceedings of the National Academy of Sciences. Tzounopoulos worked with co-authors Shuang Li and Veronica Choi of Pitt's Department of Otolaryngology.

“We worked day and night for 3½ years,” Tzounopoulos said. “It's a slow, systematic approach of constant trial and error. I am always trying to prove myself wrong. If I reach a point where I cannot prove myself wrong, I go on with it.”

Chris Togneri is a staff writer for Trib Total Media. He can be reached at 412-380-5632 or ctogneri@tribweb.com.