Drug Used to Treat Malaria Could Lessen Hearing Loss Impacts
Celebrating 35 years of Caring for Your Hearing
|Meredy Hase tests a child, 1987||Kupperman and Hase work to license audiologists in Wisconsin, 1989|
Hearing Loss UNDER Age 65
We used to think of hearing loss as something that only happened to our grandparents' generation. But you'd be surprised at how many people your age, and even younger, have a hearing problem.
According to a study recently published by the Better Hearing Institute, two-thirds of Americans with hearing loss are under the age of 65 and still in the work force. That includes one of every six "Baby Boomers" (ages 41 to 59) and one of every 14 "Generation X'ers" (age 29-40).
According to Meredy Hase, Doctor of Audiology, "Hearing loss is by no means an 'old person's disease' any longer. Each day, we see people of all ages come into our offices concerned they may have a hearing problem.
"There's even solid evidence to support the fact that for working Americans, hearing loss impacts their ability to make a living, up to $12,000 in lost income per year." (See related article)
Dr. Hase urges anyone who thinks they, or a loved one, may have a hearing loss to contact The Doctors of Audiology at Hearing Services without delay.
Auditory Deprivation refers to the fact that even though we "hear" with our ears, it's our brain that's the true organ of hearing.
When hearing loss is left untreated, the brain's ability to distinguish various sounds becomes less and less. Try to think of Auditory Deprivation as similar, in a sense, to muscles that atrophy when not used over a long period of time.
The reason Auditory Deprivation is important is that we have ample evidence proving how long people will wait before seeking help for a suspected hearing loss. Up to ten years, by some estimates.
In other words, the longer you wait to get help for your hearing loss, the less even the most advanced hearing instruments will be able to help you hear better. That's one more reason physicians recommend annual hearing checks as part of an overall health assessment.
The Doctors of Audiology at Hearing Services can perform hearing screenings that take only a few minutes. Concerned individuals are urged to contact them at the first signs of hearing loss, such as an inability to understand conversations in a crowded room or having to turn up the TV volume in order to hear.
Hearing & Income Loss
After years of research, there is new evidence that links hearing loss and loss of income. A study released by the Better Hearing Institute in Alexandria, VA, proves that untreated hearing loss may impact household income by as much as $12,000 per year.
The study also shows that hearing loss, which affects more than 28 million Americans, two thirds of whom are still in the work force, results in an annual loss of more than $100 billion in wages and worker productivity. The good news is people who find help for their hearing loss can regain up to 50% of that lost income.
According to Meredy Hase, Doctor of Audiology, "One of the misconceptions about hearing loss is that it's 'an old person's ailment'. But we know that hearing loss crosses all income lines and impacts people of all ages".
The new "Open Ear" Digital hearing instruments are especially designed to help Baby Boomers feel more comfortable about wearing hearing instruments.
Anyone interested in receiving a FREE Demonstration of Open Fit hearing technology are urged to contact the Doctors of Audiology at Hearing Services.
Hearing Loss & the Family
For years, both researchers and hearing healthcare professionals have known much about the causes of hearing loss and how it affects the person who suffers from it.
But not until recently has attention been paid as to the devastating effects hearing loss has on family members and friends as well. This past year alone, several organizations have weighed in with their findings on this often overlooked medical problem that by current estimates, affects the lives and families of more than 30 million Americans.
For example, the National Council on Aging (NCOA), a government agency whose task it is to research the lives of older Americans, released a study that confirms how often a person with hearing loss begins to feel isolated, eventually withdrawing from normal everyday activities and even from family and friends.
None of this is news, however, to Dr. Meredy Hase, who says, "I realized just how much hearing loss also affected family members when we''d spend so much time counseling them when we''d fit their loved one with hearing instruments".
The benefits of better hearing were the subject of an NBC report that aired on an installment of the NBC Nightly News. In that report, the testimonials of several patients and their families provided evidence of how lives can be changed for the good, once the decision has been made to seek help for a hearing problem.
Those interviewed talked about how experiences such as watching TV or enjoying conversations with loved ones - things that were not possible with hearing loss - were once again part of the everyday enjoyment of life. Social activities like dining at restaurants of going to the movies were also among the range of family life experienced through better hearing.
Thanks to recent advances in technology more help is available than ever before for those whose lives are affected by hearing loss. If left untreated, hearing loss will almost always become worse over time, another reason Dr. Hase urges people to contact the Doctors of Audiology at Hearing Services if a hearing loss is thought to exist.
More Hearing Healthcare News
The ability to hear depends on proteins to reach the outer membrane of sensory cells in the inner ear. But in certain types of hereditary hearing loss, mutations in the protein prevent it from reaching these membranes. Using a zebrafish model, researchers at Case Western Reserve University School of Medicine have found that an anti-malarial drug called artemisinin may help prevent hearing loss associated with this genetic disorder.
In a recent study, published in the Proceedings of the National Academy of Sciences (PNAS), researchers found the classic anti-malarial drug can help sensory cells of the inner ear recognize and transport an essential protein to specialized membranes using established pathways within the cell.
The sensory cells of the inner ear are marked by hair-like projections on the surface, earning them the nickname "hair cells." Hair cells convert sound and movement-induced vibrations into electrical signals that are conveyed through nerves and translated in the brain as information used for hearing and balance.
The mutant form of the protein-clarin1-render hair cells unable to recognize and transport them to membranes essential for hearing using typical pathways within the cell. Instead, most mutant clarin1 proteins gets trapped inside hair cells, where they are ineffective and detrimental to cell survival. Faulty clarin1 secretion can occur in people with Usher syndrome, a common genetic cause of hearing and vision loss.
The study found artemisinin restores inner ear sensory cell function -- and thus hearing and balance -- in zebrafish genetically engineered to have human versions of an essential hearing protein.
Senior author on the study, Kumar N. Alagramam, PhD, The Anthony J. Maniglia Chair for Research and Education, and associate professor at Case Western Reserve University School of Medicine Department of Otolaryngology at University Hospitals Cleveland Medical Center, has been studying ways to get mutant clarin1 protein to reach cell membranes to improve hearing in people with Usher syndrome.
"We knew mutant protein largely fails to reach the cell membrane, except patients with this mutation are born hearing," Alagramam said. "This suggested to us that, somehow, at least a fraction of the mutant protein must get to cell membranes in the inner ear."
Alagramam's team searched for any unusual secretion pathways mutant clarin1 could take to get to hair cell membranes. "If we can understand how the human clarin1 mutant protein is transported to the membrane, then we can exploit that mechanism therapeutically," Alagramam said.
For the PNAS study, Alagramam's team created several new zebrafish models. They swapped the genes encoding zebrafish clarin1 with human versions -- either normal clarin1, or clarin1 containing mutations found in humans with a type of Usher syndrome, which can lead to profound hearing loss.
"Using these 'humanized' fish models," Alagramam said, "we were able to study the function of normal clarin1 and, more importantly, the functional consequences of its mutant counterpart. To our knowledge, this is the first time a human protein involved in hearing loss has been examined in this manner."
Zebrafish offer several advantages to study hearing. Their larvae are transparent, making it easy to monitor inner ear cell shape and function. Their genes are also nearly identical to humans -- particularly when it comes to genes that underlie hearing. Replacing zebrafish clarin1 with human clarin1 made an even more precise model.
The researchers found the unconventional cellular secretion pathway they were looking for by using florescent labels to track human clarin1 moving through zebrafish hair cells. The mutated clarin1 gets to the cell membrane using proteins and trafficking mechanisms within the cell, normally reserved for misfolded proteins "stuck" in certain cellular compartments.
"As far as we know, this is the first time a human mutant protein associated with hearing loss has been shown to be 'escorted' by the unconventional cellular secretion pathway," Alagramam said. "This mechanism may shed light on the process underlying hearing loss associated with other mutant membrane proteins."
The study showed the majority of mutant clarin1 gets trapped inside a network of tubules within the cell analogous to stairs and hallways helping proteins, including clarin1, get from place to place. Alagramam's team surmised that liberating the mutant protein from this tubular network would be therapeutic and tested two drugs that target it: thapsigargin (an anti-cancer drug) and artemisinin (an anti-malarial drug).
The drugs did enable zebrafish larvae to liberate the trapped proteins and have higher clarin1 levels in the membrane; but artemisinin was the more effective of the two. Not only did the drug help mutant clarin1 to reach the membrane, hearing and balance functions were better preserved in zebrafish treated with the anti-malarial drug than untreated fish.
In zebrafish, survival depends on normal swim behavior, which in turn depends on balance and the ability to detect water movement, both of which are tied to hair cell function. Survival rates in zebrafish expressing the mutant clarin1 jumped from 5% to 45% after artemisinin treatment.
"Our report highlights the potential of artemisinin to mitigate both hearing and vision loss caused by clarin1 mutations," Alagramam said. "This could be a re-purposable drug, with a safe profile, to treat Usher syndrome patients."
Alagramam added that the unconventional secretion mechanism and the activation of that mechanism using artemisinin or similar drugs may also be relevant to other genetic disorders that involve mutant membrane proteins aggregating in the cell's tubular network, including sensory and non-sensory disorders.
Article originally appeared on Science Daily