A study led by an Indian-origin researcher from the Baylor College of Medicine has found that levels of cholesterol in the membranes of hair cells in the inner ear may affect hearing.
Dr Lavanya Rajagopalan, a postdoctoral fellow in otolaryngology at BCM, carried out this study in collaboration with Rice University and Purdue University. “We’ve known for a long time that cholesterol is lower in the outer hair cell membranes than in the other cells of the body,” said Dr William Brownell, professor of otolaryngology at BCM, who is the senior author of the report.
“What we didn’t know was the relationship it had to hearing,” he added.
The inner ear comprises of two types of sensory hair cells, called the inner and outer hair cells. It is the outer hair cells that are affected by cholesterol levels, and produce the inaudible sounds.
Researchers measured the mice’s hearing ability and manipulated the cholesterol levels in the outer hair cells. “Depleting the cholesterol resulted in a hearing loss. Adding cholesterol initially increased hearing but later resulted in a hearing loss. So you can change an animals hearing just by adding or subtracting cholesterol,” Brownell said.
“Will our hearing be affected if we continually eat greasy meals? Right now, we don’t see a connection between the two,” he said.
“The study helps us understand the cellular mechanisms for regulating hearing and give us another way to potentially help those with hearing loss,” he added.