Scientists develop method to repair damaged structures deep inside the ear
Researchers at USC and Harvard have developed a new approach to repair cells deep inside the ear -- a potential remedy that could restore hearing for millions of elderly people and others who suffer hearing loss.
The lab study demonstrates a novel way for a drug to zero in on damaged nerves and cells inside the ear. It's a potential remedy for a problem that afflicts two-thirds of people over 70 years and 17 percent of all adults in the United States.
"What's new here is we figured out how to deliver a drug into the inner ear so it actually stays put and does what it's supposed to do, and that's novel," said Charles E. McKenna, a corresponding author for the study and chemistry professor at USC Dornsife College of Letters, Arts and Sciences. "Inside this part of the ear, there's fluid constantly flowing that would sweep dissolved drugs away, but our new approach addresses that problem. This is a first for hearing loss and the ear. It's also important because it may be adaptable for other drugs that need to be applied within the inner ear."
The paper was published April 4 in the journal Bioconjugate Chemistry. McKenna co-authored it with David Jung of Harvard Medical School, among others. It is the latest achievement in USC's priority program to advance biomedicine, including the recent launching of the USC Michelson Center for Convergent Bioscience. The Michelson Center unites USC experts across disciplines to solve some of the most intractable research challenges related to health at the molecular level. The facility will house the new USC Center of Excellence in Drug Discovery, with McKenna as its director.
There are caveats. The research was conducted on animal tissues in a petri dish. It has not yet been tested in living animals or humans. Yet, the researchers are hopeful given the similarities of cells and mechanisms involved. McKenna says since the technique works in the laboratory, the findings provide "strong preliminary evidence" it could work in living creatures. They are already planning the next phase involving animals and hearing loss.
The study breaks new ground because researchers developed a novel drug-delivery method. Specifically, it targets the cochlea, a snail-like structure in the inner ear where sensitive cells convey sound to the brain. Hearing loss occurs due to aging, working with noisy machines and too many loud concerts. Over time, hair-like sensory cells and bundles of neurons that transmit their vibrations break down, as do ribbon-like synapses, which connect the cells.
The researchers designed a molecule combining 7,8-dihydroxyflavone, which mimics a protein critical for development and function of the nervous system, and bisphosphonate, a type of drug that sticks to bones. The pairing of the two delivered the breakthrough solution, the researchers said, as neurons responded to the molecule, regenerating synapses in mouse ear tissue that led to repair of the hair cells and neurons, which are essential to hearing.
"We're not saying it's a cure for hearing loss," McKenna said. "It's a proof of principle for a new approach that's extremely promising. It's an important step that offers a lot of hope."
Hearing loss is projected to increase as the U.S. population ages. Previous research has shown that hearing loss is expected to nearly double in 40 years. Damage to the inner ear can lead to "hidden hearing loss," which is difficulty hearing whispers and soft sounds, especially in noisy places. The new research gives hope to many hoping to avoid loss of hearing and quality of life.
The authors include lead researcher Judith S. Kempfle, as well as Christine Hamadani, Nicholas Koen, Albert S. Edge and David H. Jung of Harvard Medical School and The Eaton-Peabody Laboratories in Boston. Kempfle is also affiliated with the University of Tu?bingen Medical Center. Corresponding author Charles E. McKenna, as well as Kim Nguyen and Boris A. Kashemirov, are in the USC Dornsife College of Letters, Arts and Sciences.
This work was supported by the American Academy of Otolaryngology-Head and Neck Surgery Herbert Silverstein Otology and Neurotology Research Award, the American Otological Society Research Grant, and by a $567,783 grant from the National Institute of Deafness and other Communicative Disorders (R01 DC007174).
About the USC Michelson Center for Convergent Bioscience
The USC Michelson Center for Convergent Bioscience, located in Michelson Hall, brings together a diverse network of premier scientists and engineers from the USC Dornsife College of Letters, Arts and Sciences, USC Viterbi School of Engineering and Keck School of Medicine of USC to solve some of the greatest intractable problems of the 21st century - from cancer, to neurological disease, to cardiovascular disease. With a generous $50 million gift from Gary K. Michelson, a retired orthopedic spinal surgeon, and his wife, Alya Michelson, the USC Michelson Center for Convergent Bioscience occupies the largest building on campus, a state-of-the-art facility for USC to transform and influence the course of scientific discovery and biomedicine for generations to come. Information about the USC Michelson Center for Convergent Bioscience is available at https:/
Gary Polakovic | EurekAlert!
Research offers clues for improved influenza vaccine design
09.04.2018 | NIH/National Institute of Allergy and Infectious Diseases
Injecting gene cocktail into mouse pancreas leads to humanlike tumors
06.04.2018 | University of Texas Health Science Center at San Antonio
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
The Atlantic overturning – one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards – is weaker today than any time before in more than 1000 years. Sea surface temperature data analysis provides new evidence that this major ocean circulation has slowed down by roughly 15 percent since the middle of the 20th century, according to a study published in the highly renowned journal Nature by an international team of scientists. Human-made climate change is a prime suspect for these worrying observations.
“We detected a specific pattern of ocean cooling south of Greenland and unusual warming off the US coast – which is highly characteristic for a slowdown of the...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
18.04.2018 | Materials Sciences
18.04.2018 | Materials Sciences
18.04.2018 | Materials Sciences