UK scientists report a great advance in their attempt to find the deafness cure, after the stem cells usage to recover hearing in animals. The hearing was essentially restored after the stem cells usage to rebuild the damaged nerves of the gerbils, which pass the signal from their ears to the brain.If the same practice is to be used on humans, person who cannot hear traffic now will hear the conversations in normal voice – UK scientist Dr. Marcello Rivolta reports to the Nature journal.
Unfortunately, human treatments are still a very distant opportunity. To say things briefly, your air transforms sound waves into electrical signals and bypasses them to the brain, which can understand and interpret them. This transformation occurs deep inside the volume of your inner ear, where sound waves move microscopic hairs and this gentle movement creates stable electrical signals.
However, currently 1 out of 10 people has progressing ear conditions, which result in nerves being unable to pick up that signal from the inner ear hairs.The research goal was in replacing those damaged nerves, known as spiral ganglion neurons, with the new ones, grown from the stem cells.
Stem cells of an embryo can become any cells in the organism, from hair and skin to bones and muscles. Their transformation possibilities are unlimited, the question is to discover the corresponding command mechanisms. The chemical solution has activated the stem cells, forcing them to become ganglion-alike cells, which afterwards were gently placed into the inner ear areas of 20 nearly deaf gerbils.
In 10 weeks, many of them had improved hearing and 45% had recovered it about 90%. This is a tremendous success. However, these treatments were not 100% effective, as the subjects still do not hear whispers and quiet sounds. Moreover, about 30% had from little to none response to the treatment. Gerbils were used for tests, as their hearing range is nearly similar to humans, unlike mice, which can hear much higher sounds. The improvement was registered by measuring the increase of brainwaves activity. The term of 10 weeks for gerbils also means about 2 years for humans, so there currently is a large field for future improvements. Questions about ethics of using stem cells also remain and need to be answered.
Prof. David Moore, the director of the Hearing Research Institute in Nottingham, explained the BBC this study was “a big moment and a really major success. The problem in using this treatment for people is mostly about getting into the inner ear area to place the cells, as it is extremely small and hard to operate, so this is a great challenge for the researchers”. Dr Ralph Holme, the head of the biomedical research group for the Hearing Loss project said it was “a tremendously encouraging study. For millions of people who have impaired hearing, this is a glimpse of hope, a promise of help in the not-so-far future”.