Stem Cells Cure Hearing Loss?

Here’s a review on how stem cells are being used to help treat and cure hearing loss

Deaf gerbils ‘hear again’ after stem cell cure

September 2012

Deaf gerbils ‘hear again’ after stem cell cure,” BBC News has reported. “UK researchers have taken a huge step forward in treating deafness” the broadcaster added. This news, reported in most places today, is based on a study that examined the possibility of treating a specific type of deafness known as auditory neuropathy. This is a condition where specialised nerve cells involved in hearing become damaged or die, for reasons that aren’t fully understood. In this study, the researchers experimented by replacing the damaged nerve cells with new ones grown from human stem cells. Stem cells are essentially biological “building blocks” that have the ability to transform into a wide range of specialised cells, including nerve cells. They then injected these new cells into the inner ears of deliberately deafened gerbils, and measured their responses to sound both before and after the transplant.  Full Story

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Cord Blood Stem Cells Restore Toddler’s Hearing

July 2012

But a simple experimental procedure that Connor enrolled in for Madeleine may have restored her hearing and reversed her condition. In January 2012, Madeleine, 2, became the first child to undergo an experimental hearing loss treatment through an FDA-approved trial at Memorial Hermann-Texas Medical Center that infused stem cells from her own banked cord blood into her damaged inner ear. Within the last six months, Connor says she’s seen a dramatic improvement in Madeleine’s ability to hear. “Before, when she would hear something she would look all around,” Connor said. “But now we notice that she turns in the right direction of the sound.” Madeleine was also able to speak for the first time, Connor said. For more than two decades, umbilical cord blood transplantation — either by a baby’s own cord blood or another’s, depending on the type of procedure — has been used to treat otherwise fatal diseases including blood disorders, immune diseases, and some types of cancers.  Full Story

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Stem Cells for Relieving Age-Related Hearing Loss

June 2012

Stem cells, or other replacement cells, provide new options treating illnesses or disorders resulting from cell loss in the body. Stem cells have the capacity to turn into other types of cell and can be obtained from various sources, including the patient. We examine one potential way that stem cell replacement could prevent age-related hearing loss by preventing degeneration of certain cells of the cochlea. The cochlea’s ability to transduce acoustic energy, delivering signals perceived as sound, declines with age. Hearing frequency ranges for humans at birth is from 20 Hz to 20 kHz, and presbycusis occurs between 16 kHz to 18 kHz, progressing lower and resulting in speech difficulties and localizing sound in noisy environments.  Full Story

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US begins stem cell trial for hearing loss

April 2012

US researchers have begun a groundbreaking trial to test the potential of umbilical cord blood transplants, a kind of stem cell therapy, to treat and possibly reverse hearing loss in infants. The phase I trial follows promising studies on mice showing that such transplants were able to rebuild the structures of the inner ear, and some anecdotal evidence from humans, sparking hope of a cure for some forms of deafness. One of those people is two-year-old Finn McGrath, who suffered brain damage after being deprived of oxygen during a prolonged and complicated delivery, according to his mother, Laura. “His doctors told us he was at high risk for cerebral palsy, vision issues, hearing problems and mental retardation,” she said in an interview with AFP.  Finn’s early days were an all-out struggle to survive, so for his parents, learning that he had failed his hearing tests and had damaged hair cells — the sensory receptors in the inner ear that pick up sounds — was almost an afterthought.  Full Story

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Deafness cure breakthrough as scientists create tiny ear hairs from stem cells

May 2010

Scientists have made delicate ear cells in a dish paving the way for a cure for deafness. Grown in their thousands, the delicate hairs could be transplanted into the inner ear, restoring hearing to millions. Some confidence-zapping balance disorders could also be eased, the researchers believe. The breakthrough – which comes after 10 years of painstaking research – could also speed the search for new drug treatments that could prevent people from becoming hard of hearing. Age-related hearing loss affects one in two Britons aged 60 and over and there is currently no way of holding it at bay. Although it is often dismissed by younger people as a minor irritation, it can have a devastating effect on self confidence and cause sufferers to become socially isolated.  Full Story

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Cord Blood Stem Cells Repair Mouse Inner Ear

August 2009

Results: The authors found that HSC migrated and engrafted into the cochlea of the deaf mice and that the levels of engraftment correlated with both the severity of damage and the treatment dose. Analysis at 60 days post-treatment showed that the mice in the HSC treatment group had well-repaired cochlea with dramatic hair cell regrowth, while control mice showed no sign of repair or hair cell regeneration.

Conclusion: The study shows dramatic repair of cochlear damage in mice after intravenous infusion of cord blood HSC, suggesting a potential therapeutic strategy using cord blood stem cells in hearing rehabilitation therapies.  Full Story

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Stem cells may help deaf people hear

April 2009

Stem cells may help deaf people hear again, according to early stage research by British scientists. A team at the University of Sheffield said on Thursday they had discovered how to turn stem cells into ones that behave like sensory hair cells or auditory neurons, which could then be surgically inserted into the ear to restore lost hearing. Lead researcher Marcelo Rivolta said the approach, which is being tested on animals, held significant potential but was a long way from being offered to patients.  Full Story

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First Embryonic Stem-Cell Trial Gets Approval From the FDA

January 2009

In a watershed moment for one of the most contentious areas of science and American politics, the U.S. Food and Drug Administration cleared the way for the first-ever human trial of a medical treatment derived from embryonic stem cells. Geron Corp., a Menlo Park, Calif., biotechnology company, is expected to announce Friday that it received a green light from the agency to mount a study of its stem-cell treatment for spinal cord injuries in up to 10 patients. The announcement caps more than a decade of advances in the company’s labs and comes on the cusp of a widely expected shift in U.S. policy toward support of embryonic stem-cell research after years of official opposition. “This is the dawn of a new era in medical therapeutics,” said Thomas B. Okarma, Geron’s president and chief executive officer. The hope that stem-cell therapy will repair and regenerate diseased organs and tissue “goes beyond what pills and scalpels can ever do.” Limits on stem-cell research, which prevented federal funding and were imposed by Congress and former President George W. Bush for ethical and religious reasons, have had a chilling effect on both academic and corporate research involving such cells. Proponents of stem-cell research say restrictions have delayed development of promising new treatments, while critics contend that harvesting stem cells from embryos destroys human life.  Full Story

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Umbilical Stem Cells May Repair Damaged Cochlear Hair Cells

September 2008

According to an Italian research team publishing their findings in the current issue of Cell Transplantation (17:6), hearing loss due to cochlear damage may be repaired by transplantation of human umbilical cord hematopoietic stem cells (HSC) since they show that a small number migrated to the damaged cochlea and repaired sensory hair cells and neurons. For their study, the team used animal models in which permanent hearing loss had been induced by intense noise, chemical toxicity or both. Cochlear regeneration was only observed in animal groups that received HSC transplants. Researchers used sensitive tracing methods to determine if the transplanted cells were capable of migrating to the cochlea and evaluated whether the cells could contribute to regenerating neurons and sensory tissue in the cochlea.  Full Story