WKU News

Congratulations to Dr. Michael Smith, Professor of Biological Sciences, for receiving a KY INBRE Student Development Research Award (SDRA) for his project: The otoprotective role of melanin in the teleost inner ear.

The KY INBRE Student Development Research Award supports Dr. Smith’s mentorship of pre-med WKU undergraduate student Lily Newton. Lily’s training in biomedical research will help prepare her for medical school. This award funds Lily's involvement plus research animals and supplies – directly advancing student training and discovery.

Dr. Smith’s research explores why African Americans have a lower prevalence of hearing loss than Caucasians – potentially due to melanin's protective role in the ear. Using black and white koi fish as models, Dr. Smith examines auditory sensory hair cells after noise exposure, predicting less hair cell loss in black koi. Insights could inform therapeutics to prevent hearing loss in humans.

Dr. Smith elaborated on the potential protective role of melanin in hearing:

“Since I have been studying hearing loss for 25 years, I have read papers that found that a lack of the pigment melanin is often associated with deafness in mammals.  For example, white cats with blue eyes are generally deaf, one-fourth of Dalmatian dogs are born deaf, and fully albino cats occasionally exhibit deafness.  This also extends to humans, in which disorders affecting melanin are associated with hearing loss. For example, vitiligo, a common depigmenting disorder caused by the autoimmune destruction of melanocytes, is associated with hearing loss. Race also plays a role in hearing loss, with blacks exhibiting less hearing loss than white individuals. This seems to indicate that the pigment melanin may play a role in hearing ability or protection against deafness.”

Previous studies in Dr. Smith’s lab have reinforced this hypothesis, demonstrating that darkly pigmented fish experience less noise-induced hearing loss than white-pigmented fish, indicating that fish with varying pigmentation levels could serve as valuable models for investigating melanin’s protective effects against hearing loss. Dr. Smith further explained: 

“If melanin does exhibit otoprotective effects, then future studies will examine the molecular mechanisms of this protection and how clinicians would treat patients to get melanin into the inner ear, especially since melanin is very insoluble.  First of all, the treatment would need to be given before exposure to loud sounds (for individuals working in environments with potentially dangerous noise levels such as the military or factories).  Secondly, because of its insolubility, the treatment would optimally promote the body’s natural melanin production.  One potential therapeutic would be melanocyte-stimulating hormone.  This could be tested in fish models first and then applied to mammalian models of hearing loss.”

Outside the lab, Dr. Smith enjoys kayaking and fly-fishing in South-central Kentucky's rivers.

See the KY INBRE feature here.