Stem cells help deaf gerbils hear
Could stem cell treatments one day replace hearing aids? Research is still preliminary.
September 12th, 2012
01:01 PM ET

Stem cells help deaf gerbils hear

About 37 million Americans have some level of hearing problem, and science hasn't come up with a perfect solution to restore this valuable sense.

Help may be on the way, at least in theory. A team of researchers reports in the journal Nature that they have used embryonic stem cells to restore some hearing in impaired gerbils. But more investigation is necessary before the technology can move to humans.


Everyone has two main sensory cell types associated with hearing: the hair cell and the auditory neuron. Hair cells take sound and make it into an electrical signal. Neurons pick up the signal and transfer it to the brain, so you know what you're hearing.

Most deafness is caused by a problem in one or both of these cells, said Marcelo Rivolta, senior author of the study and stem cell biologist at the University of Sheffield, United Kingdom. The cells are usually created during the embryonic stage of development.

"Adult mammals have lost the ability to replace these cells," Rivolta said. In other words, if these cells are damaged, you can't naturally grow them back.

Cochlear implants are electronic devices designed for people with hearing loss, but they don't work well in people with auditory nerve damage, Rivolta said.

How they did it

Researchers used a drug to chemically damage the auditory nerve in gerbils, creating a condition that would be called auditory neuropathy.

To see if hearing could be brought back, researchers used human embryonic stem cells, and applied biological factors to them that the human body would naturally use in its development. This coaxed them into becoming otic progenitor cells, which can differentiate into cells that function as hair cells and auditory neurons.

The scientists injected the progenitor cells into the gerbils to see if they would restore hearing function. Since you can't ask a gerbil what it hears, they used a technique called auditory brain stem response to determine if the animal was receiving auditory input. If the brain is hearing sound, it produces an electrical wave that the surface electrodes pick up.


Before the treatment, a human with the gerbils' level of impairment would only be able to hear loud sounds, such as a truck driving by, Rivolta said.

After the stem cell therapy, the gerbils' hearing was, on average, restored to the level that a person would be able to engage in conversation in a busy environment, he said. Scientists saw a range of success in the gerbils: some showed almost complete recovery, while others had a weaker response.

Eighteen of the gerbils received cell transplants, while eight did not. Those eight did not show any signs of recovery.

Next steps:

There's still a long way to go before this stem cell therapy is given routinely to humans. Even before it gets to clinical trials, the method must be tested further in animals to see whether the hearing recovery is permanent. Rivolta and colleagues only have data for 10 weeks of observing the animals; they would like to see what happens a year after the therapy.

This is "a proof of concept, a validation that stem cells can be used to repair the damaged ear," Rivolta said.

More: Hearing loss an 'invisible,' and widely uninsured, problem

soundoff (64 Responses)
  1. karlotious

    back off religious nuts we are changing the world while you attempt to hold us back and stagnate

    September 12, 2012 at 14:38 | Report abuse | Reply
    • karek40

      we will probably create the next uncurable black death and significantly decrease the over population problem.

      September 12, 2012 at 15:15 | Report abuse |
    • bobnotbob

      All of the progress being made with stem cell is with adult stem cells, not fetal stem cells. There is no objection from religious conservatives on the use of adult stem cells.

      Do try to keep up.

      September 14, 2012 at 00:06 | Report abuse |
    • bspurloc

      not true.... the WORLD uses whatever stem cells they have.... here in the USA we are held back by religious nutcases... just like Islam held back and stopped Muslim Scholars

      September 14, 2012 at 15:36 | Report abuse |
    • A scientist

      bobnotbob: Your comments might be more insightful if you read the article before commenting. This study was done with embryonic stem cells, not adult ones. This is one of a number of important studies with embryonic stem cells.

      The reality is that adult and embryonic stem cells each have specific advantages. If you want to object to embryonic stem cells based on religious or moral reason, that's fine - I disagree, but at least we can have an honest discussion; however, this nonsense of pretending that embryonic stem cells are not useful is just dishonest, and discredits your side.

      September 15, 2012 at 17:21 | Report abuse |
  2. bert f.

    The deaf culture prefers to not have their hearing corrected by any kind of operation. It would take time to get the deaf culture to accept a stem cell 'repair' solution to deafness.

    September 12, 2012 at 14:54 | Report abuse | Reply
    • karek40

      Those of us (myself included) that no longer hear with any kind of background noise present would love some manner of correction. About 90+ db down.

      September 12, 2012 at 15:13 | Report abuse |
    • JohnF

      Shut up Bert. As a person born hard-of-hearing and I'm now 54; it would be a godsend to have normal hearing. Yes I'm aware that some deaf people don't want to be thought of as impaired, and "say" that they don't want their hearing fixed, but they're a small minority. Most people would rather have normal hearing, and I have no doubt that those deaf people who say they don't want normal hearing would ALL change their minds and want to keep their normal hearing if they could get it.

      September 12, 2012 at 15:14 | Report abuse |
    • Chris R

      this would be more of a treatment for people with hearing loss due to age or injury than those born deaf or deaf from an early age.

      September 12, 2012 at 15:16 | Report abuse |
    • Meghan

      That is true, however I am someone with a hearing loss who has never been apart of Deaf culture and this would be something I would be interested in.

      September 12, 2012 at 18:17 | Report abuse |
    • SixDegrees

      That view is not widespread; it is a distinctly minority opinion. The majority of people with diminished hearing would be thrilled to have it repaired.

      September 14, 2012 at 05:03 | Report abuse |
  3. james

    I know..theres a million jokes here...but cant think of 1 right now.

    September 12, 2012 at 14:55 | Report abuse | Reply
    • Ken Buck

      Not sure why, but Richard Geer does come to mind for a couple of them jokes. LOL

      September 12, 2012 at 21:46 | Report abuse |
  4. hecep

    I don't see why modern medicine can't just fit these gerbils with hearing aids. Sure. The aids would be absolutely enormous relative to the animal's tiny size and weight, but hey! It's not like there's a shortage of batteries.

    September 12, 2012 at 14:59 | Report abuse | Reply
    • karek40

      Love it, lol

      September 12, 2012 at 15:11 | Report abuse |
  5. Clay

    I am religious...I don't go to church as much as I should, but I do believe in the teachings of the Bible. With that said...please get rid of all the rediculous governmental programs that should not be in place and give every single dollar to funding Stem Cell Research.

    September 12, 2012 at 15:00 | Report abuse | Reply
    • karek40

      Which ones should not be in place, who gets to decide, are you going to pay to abort babies to harvest their stem cells?

      September 12, 2012 at 15:10 | Report abuse |
    • Ali P

      I have read quite a bit of research where they use stem cells that aren't harvested from a fetus. Adults actually have stem cells and it doesn't require taking a life to use them. I would support that kind of research. I think we need to be very careful about harvesting stem cells from fetuses or creating a fetus purely for that purpose.

      September 13, 2012 at 16:36 | Report abuse |
    • BigRed

      That's fine, so long as your church no longer gets tax cuts from my government either.

      September 15, 2012 at 13:04 | Report abuse |
    • another scientist

      Now Karek: whether you or I or anyone likes it, embryos are discarded/aborted in this country every single day. Embryonic stem cells must be harvested from very early embryos, not fetuses. Ideally, they would come from 4-16 cell embryos leftover from in vitro fertilization attempts that are no longer wanted. Imagine using such a precious gift rather than just throwing those cells away. These embryos aren't created for cell harvest, they are left over from a couple's attempt to have kids and they will be destroyed. Using something that would just be thrown away is always the better option. Reduce, reuse, recycle.

      I am signed up to give away all my useable tissues when I die. If they are useable and I can't use them after I die, I will give them to someone who can.

      September 15, 2012 at 20:11 | Report abuse |
  6. phazon

    This is the only thing I am going to say how come with science with all of its self proclaimed wisdom cannot see we are deteriating instead of evolveing? why is it that nothing on record for the past million years that science has tried to say we evolved how come nothing has evolved in that time frame? I am on the fence at stem cell research you make the conciounce choice if you feel its ok with God Almighty.

    September 12, 2012 at 15:03 | Report abuse | Reply
    • Chris R

      Actually there are clear signs of evolution. Most mammals – including humans – lose the ability to digest milk (lactose specifically) shortly after weaning. In the case of humans that's around 4 or 5. However, around 7,000 years ago two groups emerged with the ability to continue to digest milk after weaning – Northern Europeans and the Masai. Inside of a a thousand years or so 95% of the people in those groups have acquired that trait. In other words, a mutation arose that ended up being beneficial and passed down to subsequent generations. That's what evolution is.

      I don't expect you to take my word on this but a couple minutes on google will give you a lot more information on this. Also, your time frame is off – anatomically modern humans only appeared around 200,000 years ago reaching behavioural modernity around 50,000 years ago. Not 1 million.

      September 12, 2012 at 15:24 | Report abuse |
    • MS Jackson

      Ignorance distilled to 100% purity! Please don't vote.

      September 13, 2012 at 19:08 | Report abuse |
  7. levi

    My gerbil won't listen to anything I say to him?

    September 12, 2012 at 15:08 | Report abuse | Reply
    • mendy

      OH ....he hears you very well.......he is ignoring you.

      September 12, 2012 at 15:21 | Report abuse |
    • Portland tony

      Hmmm ...You speak gerbil?

      September 13, 2012 at 09:06 | Report abuse |
    • Hahahahahahha

      Your gerbil can't hear through your butt cheeks. Let it out for air once in a while. Hahahahahahahahha

      September 14, 2012 at 09:37 | Report abuse |
  8. karek40

    Wonder what new diseases we will create mixing our cells with animal cells, if the gerbil has a disease and you can bet they do how long before it mutates and jumps to humans. We are not as knowing as we would like to believe.

    September 12, 2012 at 15:08 | Report abuse | Reply
    • The Teacher

      You're kidding, right? If that were true why would it not jump to the human handlers, with no need for the stem cell implant?

      September 12, 2012 at 15:33 | Report abuse |
    • another scientist

      Karek: those Gerbils receive embryonic GERBIL stem cells- duh! All the religious nuts out there have no problem with scientists culturing gerbil embryos to cure gerbil health problems but they sure have a problem with allowing us to USE human embryos that will be thrown away anyway. Yes, let's just let everything go to waste. No? You want to ban disposing of unwanted human embryos? I guess you will have to have them implanted into your/your wife's uterus to save them all.

      September 15, 2012 at 20:18 | Report abuse |
    • amybiddy

      another scientist...the article specifies that they used human embryonic stem cells in the gerbils, NOT gerbil embryonic stem cells...

      September 17, 2012 at 09:44 | Report abuse |
  9. lol

    Awesome! I hope we can use as many human stems cells as we can to help all the poor deaf gerbils out there.

    September 12, 2012 at 15:22 | Report abuse | Reply
    • Kel

      You obviously aren't really into science are you? This is a very exciting development. They have to test things of this nature on something like a gerbil, rat, pig, etc. before they can move to human testing... duh.

      September 15, 2012 at 02:05 | Report abuse |
  10. Zandra

    This is exciting news for folks that are hearing impaired. Keep the resarch going

    September 12, 2012 at 15:24 | Report abuse | Reply
  11. Pan3


    September 12, 2012 at 15:39 | Report abuse | Reply
  12. Ed in Reno, Nevada

    This explains why conservatives are so opposed to stem cell research...their followers (gerbils) would be able to hear the truth...but they still wouldn't listen to or believe it.

    September 12, 2012 at 15:56 | Report abuse | Reply
    • Winston5

      SWISH! 🙂

      September 14, 2012 at 23:51 | Report abuse |
  13. scr8

    See http://sdrmi.org/wordpress for hESC research advances as cures for heart and CNS diseases

    September 12, 2012 at 16:01 | Report abuse | Reply
  14. tyler

    Gerbils in a cage hissing and scratching at the sides of the cage. Eventually the gerbils mutate and are able to chew through the cage and eventually attacks the scientist and the scientist die there for enabling the gerbils to take up residence inside the scientist heads. The scientist become biological roboticly controlled and there for start a whole new race of slave controlled humans. All because of stem cells being used on gerbils.

    September 12, 2012 at 16:09 | Report abuse | Reply
  15. Greg

    Let me get this straight, they started with embryonic stem cells, differentiated them and then injected them? A long way around the block, right? Adult stem cells are already doing this. I guess someone is looking for goverment funding becasue they can't raise private capital. I'm I right?

    September 12, 2012 at 16:51 | Report abuse | Reply
    • SixDegrees

      Reading comprehend much?

      September 14, 2012 at 05:09 | Report abuse |
  16. Greg

    If you can't get private funding, just take it from the sheep!

    September 12, 2012 at 16:54 | Report abuse | Reply
  17. hecep

    Now I know why my gerbil has been ignoring my specific verbal commands.

    September 12, 2012 at 19:18 | Report abuse | Reply
  18. cthulhu jr


    September 13, 2012 at 13:49 | Report abuse | Reply
  19. Nonny

    So Richard Gere's gerbils can finally hear the echo in there.

    September 13, 2012 at 16:47 | Report abuse | Reply
    • SilentBoy741

      "In That Space, No One Can Hear Them Scream".

      Tagline from 'Gerbaliens'.

      September 13, 2012 at 17:43 | Report abuse |
  20. Elle

    How do I sign up? Cant wait. And when it can cure heart disease and help with mental illness? So much lost potential with these illness-bit by bit though. God bless scientists..

    September 13, 2012 at 19:10 | Report abuse | Reply
    • another scientist

      "God bless scientists"? It is the religious right that keeps us from doing some of our best work. Romney is going to deflate the NIH budget just like popping a balloon. It won' t be for economic reasons, it will be because science doesn't mix well with Tea Party. The Tea Party doesn't want any light shining in on it's dark, dark places. Aiken sits on the U.S. Committee for Science and Technology and he doesn't understand where babies come from. Goodbye NIH, research and hello Dark Age II.

      September 15, 2012 at 20:26 | Report abuse |
  21. Netzilla

    This is GREAT NEWS for all those gerbils who were Led Zeppelin fans!

    September 13, 2012 at 22:16 | Report abuse | Reply
  22. MG

    They did use embryonic stem cells because adult stem cells are limited in what they can do. Yes, they can do amazing things with adult stem cells, but there are many more amazing things they can't do without using embryonic stem cells. There are thousnads of "babies" thrown away from the fertility industry that doesn't draw the alleged "pro-lifers" ire and yet those can't be used. The real problem here is they don't trust or understand the science. They think that if adult stem cells have success and if you ban the use embryonic, then embryonic are useless. And yes, what Bush did effectively banned the use of them even if it wasn't an full on ban. You can't prove the usefulness of something if it's banned people. There is no need to create life to harvest embryonic stem cells, there are already ways being developed to harvest them without destroying the zygote and in the mean time we have many thrown away zygotes that can be used. If you are truly pro-life, you don't get to leave it up to God for the unborn and then play God with the living by sentencing them to death. It doesn't work that way.

    Oh, and kudos to the gerbil jokes. They are awesome!

    September 14, 2012 at 10:29 | Report abuse | Reply
  23. East of Eden

    I'm saying, if we abort babies every day–why not get something positive from the lives lost? Even religious zealots should not have a problem with that?

    September 14, 2012 at 10:55 | Report abuse | Reply
  24. se

    even if it's only temporary, I'm sure there would be plenty of volunteers....Wonderful accomplishment

    September 14, 2012 at 13:04 | Report abuse | Reply
  25. Winston5

    Glad it's not the Bush Administration anymore, we're not playing god, cra ck ers, we're advancing science. It's kinda important.

    September 14, 2012 at 23:50 | Report abuse | Reply
  26. Dan

    This is good news because every time I try to tell my pet gerbils to turn off those dang anti-Islam videos, they don't listen to me.

    But on a more somber note, the article does bring up a serious subject, will hearing aids be one day replaced by talking gerbils that sit on our shoulders and whisper to us the secrets of the world?

    September 15, 2012 at 07:37 | Report abuse | Reply
  27. Les Too

    One thing that some writers here seem to not be aware of is that the stem cells used in the gerbil experiment were gerbil stem cells NOT human ones. With all the supposed advancement in stem cell research there are many hurdles that need to be overcome. The biggest hurdle is getting scientists to actually use the research to help humans instead of rodents.

    September 15, 2012 at 12:27 | Report abuse | Reply
    • A scientist

      It is remarkable that someone could pack so much inaccurate information into just three lines. Two key things - first, you are incorrect about the source of the stem cells. The experiments did use human stem cells, not hamster ones.

      Second, there is a very good reason that scientists are currently using this technology to "help rodents" rather than humans. It is virtually impossible to get approval for human studies without first proving effectiveness in model organisms such as mice. The reason for this is obvious - untested treatments can often have horrible, unpredictable side effects; although PETA might disagree, most people would rather scientists work out the kinks in any technology in mice first, rather than on human subjects. Once a treatment is proven safe and effective in other animals, scientists will naturally move onto humans.

      September 15, 2012 at 17:33 | Report abuse |
    • another scientist

      A Scientist: one cannot inject human stem cells into immunocompetent gerbils. You should know that. Gerbil stem cells are used because (1) there's no legal barrier to using them, (2) they are readily available and (3) they will make gerbil proteins with gerbil glycosylation and gerbil localization: all important things occurring inside of gerbils.

      Also, "hamster" is not the same as "gerbil".

      September 15, 2012 at 20:33 | Report abuse |
  28. JLS639

    As far as I can tell, this article is not yet available online at my university. I had many questions which will not be answered...
    The last article by Rivolta on this subject was in 2009 using human fetal auditory stem cells to create functional hair cells and auditory neurons in cell culture. Does anyone have the citation for this article?

    September 15, 2012 at 15:47 | Report abuse | Reply
  29. stem cell researcher

    In answer to bspurloc I just want you to go to this link http://www.islam101.com/science/stemCells.htm. Islam has never stopped any muslim scholars from research neither in past nor in present. Please don't confuse Islam with policies of muslim countries as they are rarely same.

    September 17, 2012 at 15:36 | Report abuse | Reply
  30. sfitz

    So exciting....!!! Now maybe my Gerbils will come when I call them

    September 19, 2012 at 19:16 | Report abuse | Reply
  31. icon designs

    I am sorry, that I interrupt you, but I suggets to go another by.


    September 21, 2012 at 23:29 | Report abuse | Reply
  32. orangedeafies

    Deaf babies are not part of deaf culture yet. Parents can picket choice to get their deaf babies ears fixed. Don't blame the society for medical advancements  like this. Blame the hearing impaired people who looked up to hearing impaired bullies as their leaders.  The hearing impaired spent too much time kissing up to their bullies to be able to prevent the field of evolution from sprouting its fruits.  See more about a hearing impaired bully at http://wp.me/p1Sx9N-1hF

    September 22, 2012 at 13:50 | Report abuse | Reply


    September 23, 2012 at 05:20 | Report abuse | Reply
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