New Stem Cell Research for Hearing Impairment

Stem cells occur naturally in the human body. They are not blood cells, nerve cells, brain cells or any other kind of cell. In fact, they have no identity by themselves, at least not yet.

They can, however, develop into different types of cells, replacing cells that have been damaged or are somehow, defective. They have the ability to clone themselves and make more stem cells.

Adult stem cells, which exist in mature body tissue and organs, continuously renew their numbers as needed throughout an individual's life, replacing damaged cells as needed. It is this fact that caused researchers to wonder if these stem cells could correct hearing loss.

When the outer ear captures the sound waves traveling through the air and then directs it into the ear canal it is said that hearing occurs. This is where you find the tympanic membrane (ear drum) and the three smallest bones in the human body namely, the stirrup, hammer and anvil. You will also find the cochlea, a snail-shaped organ that contains delicate, hair-like nerve fibers that translate sound waves into electrical impulses that are, in turn, transmitted to the brain. The hair-like nerve fibers are very delicate and can be damaged or impaired very easily due to age, disease, exposure to loud noise and other medical and non-medical conditions. Hearing-loss, most often permanent in nature, is the result of the damage to these nerves.

With this in mind, a group of researchers from the Indiana University School of Medicine under the instruction of Dr. Eri Hashino, Ph. D., set out to find out if they could transform cell nerves into sensory nerve cells, called neurons. To do this, they took stem nerves from the bone marrow of lab mice and transformed it into cells that had numerous characteristics similar to neurons. Neurons transmit sound from the outside world to the brain where the sound is processed and interpreted. These results suggest the possibility to re-grow and replace damaged neurons with the stem cells taken from bone marrow. Dr. Hashino stated that their interest in the marrow cells was due to their potential use in autologous cell-based therapy (using stem cells from a patient as a part of that patient's treatment). They were ideal for use as the bone marrow cells are easily collected and can be kept alive in the laboratory until needed.

Around the same time of Dr. Hashino's experiments, additional research was conducted in Tokyo. These studies revealed that the bone marrow stem cells injected into a damaged ear can speed hearing recovery after partial hearing loss. It showed that some re-growth of cochlear fibrocytes is possible after these cells have been damaged. However, only partial recovery was observed over a period of weeks, but patients who experience traumatic hearing loss tend to permanently lose their ability to hear high frequency sounds.

Research on the practical use of a patient's stem cells to restore or improve hearing is just beginning.

Animal studies indicate the potential to regenerate the nerves that convert sound waves into electrical impulses that are subsequently delivered to the brain for processing.

Today, the future looks bright for restoring the sense of hearing to those who have lost or are losing it.

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leong

May 28, 2009 - 23:00

Subject: Funding for research into hearing loss

hi people

I just lost my left ear hearing due to infection. I have read up a lot of studies

So broadly, these are the challenges :

1. finding a cure -

a. using stem cell (human ear nerve recently grow in lab)
b. using gene (injecting turn-on gene and suppressing turn-off gene)
c. brain material (recently discovered)

2. Delivery

3. Volunteers

4. Funding.

For 1 , I understand that there are at least 20 to 30 teams of scientists in different countries looking at hearing loss. Perhaps a solution is just round the corner.

For 2, how is a potential treatment delivered to a guinea pig inner ear ? Can't the same technique be used on human ?

For 3, I am sure there are plenty of volunteers who will sign a no-liabiliy contract to try out whatever trials there is. I can volunter also.

For 4, with at least 10 million hearing loss (due to nerve damage) sufferers in the developed and developing countries (like US, UK, European countries, Japan, Korea, Singapore (from where I am) etc), can't we all group up and donate at least $1 each and there will be a working captial of at least $10 m annually ? May be the problem is not lack of funding but the sufferers do not know that the scientists need money and the sufferes do not know how to donate ?

Should we start something on funding for the scientists ?

My e-mail is Wongtanlim3@yahoo.com

Alison

May 11, 2009 - 21:12

Subject: 19 yr. old daughter with profound bi-lateral hearing loss with severe pain and headaches

2 years ago our daughter was diagnosed with bilateral hearing loss and was profound and complete in the right ear. She has progressive sensorineural loss in the left ear. She has been on and off steroids and this did not afford her any benefits. She is wearing a hearing aid by Beltone called The Force but we feel she is still losing hearing. She has sudden headaches that feel like knives in her skull and ear pain. She has been accepted to college and is concerned about total hearing loss. We have spent time in Boston, MA. with a Dr. Quinton Gopen who has helped as much as he can. We are desperate for more help. We are insured and are also looking into Chinese remedys. My daughte, Kassandra done a report on stem cell resarch w/ hearing loss for college and is not opposed to trying this. Could someone please make us aware of a Dr. who may be interested in her case.?
I truly believe this could work and it's our last hope. Thank you. Alison Porter

Nathan

May 02, 2009 - 03:44

Subject: Bi-lateral moderate hearing loss

Are any clinical studies being done on human volunteers? I am a 26 year old male who has had moderate bi-lateral hearing loss all my life. The best hearing instruments are not able to give me the degree of hearing I want. It has had and continues to have a profound impact on my life. I am anxious to know of any testing that is being done on people. If there are any studies, I would like to be able to participate as a test subject.
Thanks, Nathan Astle

TJDaily

January 11, 2009 - 20:19

Subject: Cord blood repairs hearing loss

Great news! I'm familiar with this company - Cord Blood America. Website: http://www.cordblood-america.com/