Navigation Links
2 drugs protect hearing better than 1
Date:2/23/2011

Whether on a battlefield, in a factory or at a rock concert, noise-induced hearing loss is one of the most common hazards people face.

Researchers at Washington University School of Medicine in St. Louis have identified a low-dose, two-drug cocktail that reduces hearing loss in mice when given before they are exposed to loud noise. The drugs, already FDA-approved for other conditions, also treat hearing loss after noise exposure.

While both drugs are known to protect hearing on their own, this is the first study to test the two in combination.

"We found they have synergy," says Jianxin Bao, PhD, research associate professor of otolaryngology at the School of Medicine. "Two drugs at lower dosages can block more signaling pathways than one alone, improving results while reducing side effects. We got the idea from cancer and HIV studies that use multiple drugs at lower dosages."

Bao presented the work Feb. 21 in Baltimore at a meeting of the Association for Research in Otolaryngology.

In earlier work, Bao's group found that anticonvulsant drugs for treating epilepsy helped protect hearing in mice after exposure to loud noise. And other groups had determined that glucocorticoids, anti-inflammatory drugs often used to treat allergies and asthma, were also protective.

The reasons these drugs reduce noise-induced hearing loss are not well understood. But anticonvulsants are known to block calcium channels in nerve cells, and Bao's group speculates that the drug helps protect neuronal connections between hair cells and auditory neurons.

For this work, Bao and colleagues chose two drugs from the anti-epilepsy family and two from the glucocorticoid family.

"We picked drugs that have fewer side effects and that can be chronically used," says Bao, also associate professor of audiology and communication sciences.

To test each drug's ability to prevent hearing loss, they gave various doses to mice two hours before exposing them to noise. To test treatment, they administered the drugs to different groups of mice 24 hours after noise exposure.

Three of the four drugs showed increasing protection with higher doses. And two of the drugs in combination, the anticonvulsant zonisamide and the glucocorticoid methylprednisolone, showed comparable hearing protection at much lower doses than when administered alone.

While the drugs do not prevent all hearing loss following sustained exposure to noise at 110 decibels, or about the sound of a chain saw, they can significantly reduce the loss by about 10 to 30 decibels.

In other words, a mouse with normal hearing might be able to hear a sound at 30 decibels. After exposure to loud noise, that mouse might only hear sounds that reach 50 decibels. But if that mouse were treated, it might be able to hear sounds at 40 decibels. In humans, protecting 5 or 10 decibels makes a difference in being able to hear everyday speech.

Bao says their next step is to test the drugs in animals that model human hearing more closely.


'/>"/>

Contact: Julia Evangelou Strait
straitj@wustl.edu
314-286-0141
Washington University School of Medicine
Source:Eurekalert

Related medicine news :

1. The private sale of drugs in public hospitals
2. Social Anxiety and Panic - Alternative Treatment to Drugs and Therapy
3. Adapting to clogged airways makes common pathogen resist powerful drugs
4. Diabetes Drugs Avandia, Actos Tied to Fractures in Women
5. Drugs That Shift Cells Energy Find New Purpose
6. FDA Tightens Controls on Anemia Drugs
7. FDA Issues Warning on Key Asthma Drugs
8. Two Tulsa Pharmacies Penalized for Missing Prescription Drugs
9. Tests to Measure Safety of Anti-Clotting Drugs of Limited Value
10. Notch-blocking drugs kill brain cancer stem cells, yet multiple therapies may be needed
11. Scans Might Monitor Success of Alzheimers Drugs
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/24/2017)... OH (PRWEB) , ... July 24, 2017 , ... ... place August 13-17 in National Harbor, MD. This year's theme focuses on the ... the principal benchmarks for quality and integrity in testing and calibration will be ...
(Date:7/24/2017)... (PRWEB) , ... July 24, 2017 , ... A Southern ... food addiction to sexual abuse, and how she has overcome them. “Forbidden Memories: A ... in her life and how she has risen above. , In “Memories,” readers get ...
(Date:7/24/2017)... Church, VA (PRWEB) , ... July 24, 2017 ... ... and Managers, **Presented by FDAnews and MSceppa Consulting **, Aug. 22-23, 2017 – ... ends on Friday, July 28. , Increased FDA scrutiny and growing demands to ...
(Date:7/24/2017)... ... ... customizable and interactive Bible study guide for children. “The Perfect Gift” is the creation of ... accepted Christ as her Savior, yet never studied His word, surrendered to His will, or ... book to her children, so they would know the importance of the truth. She ...
(Date:7/24/2017)... ... 24, 2017 , ... The Center for Addiction Recovery Training ... host a second Multiple Pathways of Recovery Conference on October 23-26, 2017. This ... from CCAR’s foundational principle – a belief in multiple pathways of recovery, aims ...
Breaking Medicine News(10 mins):
(Date:7/20/2017)... July 20, 2017  Prime Therapeutics LLC (Prime) released this ... M.D., following today,s Institute for Clinical and Economic Review,s (ICER) ... the effectiveness and value of abuse-deterrent formulations (ADF) of opioids. ... roundtable at the meeting. ... cost benefit to the use of abuse-deterrent formulations (ADF) in ...
(Date:7/14/2017)... 2017 It should come as no surprise to ... in the midst of a crippling opioid epidemic. According to ... number of overdose deaths from opiate-based medications has quadrupled, Says, ... million dead from 2001 to 2015". During this time, the ... similarly quadrupled, drawing a compelling link between prescription and eventual ...
(Date:7/12/2017)... INDIANAPOLIS , July 12, 2017  Eli Lilly and ... settlement agreement with generic companies to resolve pending patent litigation ... Virginia regarding the Cialis ® ... expire on April 26, 2020. As part of the agreement, ... on September 27, 2018. "The unit dose patent ...
Breaking Medicine Technology: