Diabetes Drug Liraglutide Protects Against Blast-Induced Hearing Loss in Military Animal Models | Research

The takeaway

Liraglutide reduced permanent hearing loss and protected inner ear hair cells in chinchillas exposed to repeated blast waves, with the best results when given before blast exposure.

Pre-blast treatment optimal
Liraglutide provided the greatest hearing protection when administered before blast exposure, suggesting potential as a preventive measure for military personnel

What the researchers found

Liraglutide treatment reduced blast-induced permanent hearing loss and facilitated hearing restoration as measured by auditory brainstem response (ABR). The effects varied by condition: in earplug-protected ears, pre-blast liraglutide reduced acute damage severity; in open ears, liraglutide facilitated post-injury hearing restoration.

Wave I suprathreshold amplitude analysis showed pre-injury treatment mitigated blast-induced temporary damage to the peripheral auditory system. Histopathological examination confirmed that liraglutide protected cochlear hair cells against blast injury. Higher-intensity blasts (15-25 psi) caused more severe and permanent damage than lower-intensity blasts (3-5 psi). Optimal protective effects were achieved when liraglutide was administered before injury.

Why it matters

Hearing loss and tinnitus are the most common service-related disabilities among military personnel, affecting hundreds of thousands of veterans. No drug currently prevents or treats blast-induced hearing loss. Liraglutide is already FDA-approved with a known safety profile, which could accelerate clinical translation. A pre-deployment injection that protects hearing could transform military medicine.

How the study worked

Summary of multiple chinchilla studies testing liraglutide across varied conditions: low (3-5 psi) and high (15-25 psi) blast intensities, 3 and 6 repeated blasts, single and recurrent exposure patterns, and open versus earplug-protected ears. Animals were divided into pre-blast treatment, post-blast treatment, and control groups. Outcomes were assessed via auditory brainstem response (ABR) testing and cochlear tissue histology.

What this study cannot tell us

These are animal studies in chinchillas, which, while well-established for hearing research, do not perfectly model human blast exposure or hearing physiology. The optimal dose, timing, and duration of liraglutide treatment for hearing protection in humans are unknown. The studies summarized here used various conditions, making direct comparisons between experiments complex. Long-term follow-up beyond the study periods was not reported.

How to read the evidence

This is a summary of multiple preclinical studies in chinchillas — a well-established animal model for hearing research. The consistent protective findings across varied conditions strengthen the evidence, but translation to human blast-induced hearing loss requires clinical trials.

When this study was published

Published in 2025 in Military Medicine, this is a very current summary reflecting active military-funded research into pharmacological hearing protection — an area of high priority for the US Department of Defense.

The bigger picture

This study extends the neuroprotective effects of GLP-1 agonists into yet another domain — auditory protection. The inner ear's hair cells are specialized neural cells, and their protection by liraglutide aligns with the growing evidence that GLP-1 drugs protect neurons throughout the nervous system. Combined with research on GLP-1 agonists in traumatic brain injury, stroke, Parkinson's, and spinal cord injury, this positions the GLP-1 pathway as a broad neuroprotective target.

Questions still open

Could liraglutide be given to soldiers before training exercises involving blast exposure to prevent hearing damage?
Does liraglutide protect against noise-induced hearing loss from sources other than blasts, such as chronic occupational noise exposure?
What is the mechanism by which GLP-1 receptor activation protects cochlear hair cells — is it anti-inflammatory, anti-apoptotic, or both?

Common questions

Why is blast-induced hearing loss such a big military problem?

Hearing loss and tinnitus are the top two service-connected disabilities among US veterans. Repeated exposure to blasts during training and combat damages the delicate hair cells in the inner ear — cells that cannot regenerate in humans. Currently, earplugs are the only protection available, and they don't fully prevent damage from high-intensity blasts. A drug that could protect hearing cells would address one of the military's most widespread health challenges.

How might a diabetes drug protect hearing?

Liraglutide activates GLP-1 receptors, which are found on nerve cells throughout the body — including in the inner ear. Activation of these receptors triggers protective pathways that reduce inflammation, prevent cell death, and support nerve cell survival. In these studies, liraglutide protected the cochlear hair cells (which convert sound vibrations into nerve signals) from the shockwave damage caused by blasts.

Read the original research

Effects of Liraglutide on Mitigation of Hearing Loss After Repeated Blast Exposures: A Summary of Studies in Animal Model of Chinchilla.

Military medicine, 190(Supplement_2), 512-520

View on PubMed ↗Publisher’s paper ↗

Citation

Jiang, Shangyuan; Cai, Qunfeng; Bien, Alexander G; Gan, Rong Z; Jiang, Yijie. (2025). Effects of Liraglutide on Mitigation of Hearing Loss After Repeated Blast Exposures: A Summary of Studies in Animal Model of Chinchilla.. Military medicine, 190(Supplement_2), 512-520. https://doi.org/10.1093/milmed/usaf255