Possible cure for noise-induced hearing loss found
For many, hearing loss is a fact of life. The idea of a cure, especially for noise-induced hearing loss (NIHL), is one that probably hasn’t crossed a lot of people’s minds. Luckily for us, there are scientists who do think of this and the best part is that they’re making major progress.
Researchers at Weill Cornell Medical College and the Gladstone Institutes announced a major breakthrough last month in the search for a cure for NIHL. In experiments with lab mice, the researchers discovered that giving the mice doses of nicotinamide riboside (NR), or the “precursor to vitamin B3,” protected the nerves around the cochlea from damaging sound waves. The cochlea transmits sound information through nerves to the brain. Exposure to noises louder than 85 decibels (dB) damages the synapses connecting the nerves and the hair cells in the cochlea, resulting in NIHL.
NR successfully wards off this damage by increasing activity of the protein sirtuin 3 (SIRT3), which, according to the study, is crucial in the performance of the body’s mitochondria, or the cell’s “powerhouse.” Levels of the SIRT3 protein naturally decrease as you get older, which creates a number of health issues associated with aging.
"The success of this study suggests that targeting SIRT3 using NR could be a viable target for treating all sorts of aging-related disorders—not only hearing loss but also metabolic syndromes like obesity, pulmonary hypertension, and even diabetes," said Eric M. Verdin, M.D., of Gladstone Institutes, in a press release.
While the discovery is exciting, that doesn’t mean you should continue engaging in the lifestyle habits known to bring on these conditions. Watching calorie intake and exercising are still important to your overall health, not just preventing obesity. Watching sugar intake is still the healthiest way to avoid complications with diabetes. And watching your noise level exposure is still the best way to prevent hearing loss.
But the breakthrough is particularly encouraging for those who work in noisy environments, such as musicians or construction workers. While people in these professions should still wear earplugs and take care to insulate their hearing as much as possible, a future supplement of NR or SIRT3 — perhaps in a form of vitamin B3, also known as niacin — presents an opportunity to greatly reduce their chances of permanent hearing damage. Scientists are still in the preliminary stages of this research, however, and have yet to study the effects of elevated NR or SIRT3 in humans.
A safe supplement is still at least several years off, but the fact that noise-induced hearing loss can be prevented by a naturally occurring chemical compound is groundbreaking, and inspires a lot of hope for those living with noise-induced or some other form of hearing loss.
"One of the major limitations in managing disorders of the inner ear, including hearing loss, is there are a very limited number of treatments options. This discovery identifies a unique pathway and a potential drug therapy to treat noise-induced hearing loss," Dr. Kevin Brown, University of North Carolina associate professor of otolaryngology, said in the release.
In the meantime, visit your audiologist or hearing health practitioner at least once a year for a yearly ear check-up. Hearing tests are often not administered as often as they should be once you age out of elementary school. While you visit the doctor regularly for your annual physical, many physicians don’t include a hearing test in their check-up routine.